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Upcoming talks

Abstracts of recent talks (2014-2015) | Abstracts of recent talks (2012-2013) | Abstracts of recent talks (2010-2011) | Abstracts of recent talks (2008-2009) | Abstracts of recent talks (2006-2007) | Abstracts of recent talks (2004-2005) | Abstracts of recent talks (2002-2003) | Abstracts of talks given (2000-2001) | Abstracts of talks given 1998-1999 | Abstracts of talks given October, 1996 - December, 1997

Weiss Group Meetings Self-Assembly & Molecular Devices Multi-Group Meetings



Friday 5 February 2016, 820 AM
2016 International Symposium on NanoBiotechnology. NanoMedicine from discovery to clinical reality: therapeutics, delivery and imaging , CNSI, UCLA, Los Angeles, CA, USA, Wednesday 3 - Friday 5 February 2016

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Wednesday 10 February 2016
2016 International Conference on Nanoscience and Nanotechnology (ICONN), Canberra, Australia

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Thursday 12 February 2016
Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan Campus, Brisbane, QLD 4111, Australia

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The chemical, physical, and electronic connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important role that chemistry can play in making and optimizing precise contacts that preserve key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory.


Friday 13 February 2016, 3 PM
University of Melbourne, Melbourne, Australia

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The chemical, physical, and electronic connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important role that chemistry can play in making and optimizing precise contacts that preserve key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory.


Tuesday 23 February 2016, 3 PM
CNSI Conference Rooms

Thesis Defense: Alignment Effects in Molecular Assemblies
Jeffrey J. Schwartz, Department of Physics and California NanoSystems Institute, UCLA, Los Angeles, CA 90095, USA


Thursday 25 February 2016, 3 PM
2033 Young Hall

Departmental Student Seminar: From Poison to Small-Molecule Probe: Cyanide Self-Assembly for the Development of Room-Temperature Single-Molecule Spectroscopy
Andrew Guttentag, Department of Chemistry and California NanoSystems Institute, UCLA, Los Angeles, CA 90095, USA


Tuesday 8 March 2016, 630 PM
6th International Conference on Nanostructures, Monday 7 - Thursday 10 March 2016, Kish Island, Iran

Editors' Discussion: Publishing in High-Impact Journals
Paul S. Weiss, ACS Nano, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA
Ali Khandemhossieni, ACS Nano, Wyss Institute, Harvard University, Cambridge, MA, USA
Luis Liz-Marzan, Langmuir, San Sebastian, Spain
Wolfgang Parak, ACS Nano, University of Marburg, Marburg, Spain


Wednesday 9 March 2016
6th International Conference on Nanostructures, Monday 7 - Thursday 10 March 2016, Kish Island, Iran

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Sunday 13 March 2016, 6 PM, Hall E, San Diego Convention Center
American Chemical Society Meeting, Spring 2016, Fundamental Research in Colloids, Surfaces & Nanomaterials, Sunday 13 - Thursday 17 March 2016, San Diego, CA

Elucidating the Mechanism behind Spin-Dependent Charge Transport through DNA Monolayers
John M. Abendroth and Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry and Biochemistry and Materials Science and Engineering, UCLA, Los Angeles, CA 90095, USA

The possibility of selectively filtering electrons with a particular spin by chiral molecules at metal-molecule interfaces without the use of a permanent magnet has stimulated renewed interest in probing spin-dependent phenomena in adsorbed chiral molecules and assemblies. In particular, unprecedented spin selective electron transmission at room temperature has been observed through self assembled monolayers of double-stranded DNA. These surprising results demonstrate the unique and exciting potential to utilize a more versatile class of materials to combine the fields of spintronics, bioelectronics, and biomagnetics. However, the mechanism governing electron spin filtering by DNA remains elusive. Thus, we combine advanced surface chemistry with novel electrochemical characterization strategies to deconvolute the relative contributions of molecular, surface, and interface properties to spin-selective electron conduction through DNA monolayers adsorbed on ferromagnetic substrates. We probe molecular structure and substrate parameters that have been theoretically predicted to influence spin polarization such as molecular length and substrate spin-orbit coupling. Understanding the mechanism responsible for this spin-dependent effect is critical to assess the viability of implementing DNA assemblies as sources of polarized electrons in organic spintronics devices, and advancing the frontiers of room temperature spin-dependent transport.


Monday 14 March 2016, 2 PM, Room 7A, San Diego Convention Center
American Chemical Society Meeting, Spring 2016, Nicholas L. Abbott Award Symposium, Sunday 13 - Thursday 17 March 2016, San Diego, CA

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The chemical, physical, and electronic connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important role that chemistry can play in making and optimizing precise contacts that preserve key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory.


Monday 14 March 2016, 310 PM, Room 5A, San Diego Convention Center
American Chemical Society Meeting, Spring 2016, ACS Nano/Nano Letters Symposium, Sunday 13 - Thursday 17 March 2016, San Diego, CA

New Approaches to Multimodal Nanoscale Imaging and Analyses
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

As most nanoscale imaging data are oversampled, significant opportunities exist in leveraging concepts, methods, and algorithms from compressive sensing and sparsity in recording data and assembling information efficiently. Orders of magnitude expansions of dynamic range and accelerations of analyses are possible. We discuss early examples of successes in this area and point to how, with sufficiently fast algorithms, image acquisition and information assembly and convergence in nanoscience, microscopy, astronomy, reconnaissance, medicine, neuroscience, and entertainment could all be improved significantly. Nanoscale imaging tools, specifically scanning probe microscopies and spectroscopic imaging methods, are excellent testbeds for these studies both because of the programmability of acquisition and because of the relatively slow typical data acquisition rates.


Monday 14 March 2016, 8 PM, Halls D/E, San Diego Convention Center
American Chemical Society Meeting, Spring 2016, SciMix, Sunday 13 - Thursday 17 March 2016, San Diego, CA

Elucidating the Mechanism behind Spin-Dependent Charge Transport through DNA Monolayers
John M. Abendroth and Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry and Biochemistry and Materials Science and Engineering, UCLA, Los Angeles, CA 90095, USA

The possibility of selectively filtering electrons with a particular spin by chiral molecules at metal-molecule interfaces without the use of a permanent magnet has stimulated renewed interest in probing spin-dependent phenomena in adsorbed chiral molecules and assemblies. In particular, unprecedented spin selective electron transmission at room temperature has been observed through self assembled monolayers of double-stranded DNA. These surprising results demonstrate the unique and exciting potential to utilize a more versatile class of materials to combine the fields of spintronics, bioelectronics, and biomagnetics. However, the mechanism governing electron spin filtering by DNA remains elusive. Thus, we combine advanced surface chemistry with novel electrochemical characterization strategies to deconvolute the relative contributions of molecular, surface, and interface properties to spin-selective electron conduction through DNA monolayers adsorbed on ferromagnetic substrates. We probe molecular structure and substrate parameters that have been theoretically predicted to influence spin polarization such as molecular length and substrate spin-orbit coupling. Understanding the mechanism responsible for this spin-dependent effect is critical to assess the viability of implementing DNA assemblies as sources of polarized electrons in organic spintronics devices, and advancing the frontiers of room temperature spin-dependent transport.


Tuesday 15 March 2016, 440 PM, Upper Level Ballroom 20A, San Diego Convention Center
American Chemical Society Meeting, Spring 2016, Biosensing of Proteins, Peptides, DNAs and RNAs, Sunday 13 - Thursday 17 March 2016, San Diego, CA

Multiplexed Neurochips as Screening Platforms for Neurotransmitter-Specific High-Affinity Aptamers
Nako Nakatsuka, California NanoSystems Institute and Department of Chemistry & Biochemistry, UCLA, Los Angeles, CA 90095, USA

Investigating integrated central nervous system neural circuitry at time scales pertinent to information encoding necessitates chemically specific in vivo neurotransmitter sensors that approach the size of nanometer-sized synapses and respond in milliseconds or less. To tackle this challenge, we employ aptamers as artificial receptors, which have emerged as superior synthetic alternatives to antibodies for molecular recognition. However, to realize their full potential for neurotransmitter biosensing, novel nanotools need to be developed that enable substrate-based high affinity interactions between tethered neurotransmitters and nucleic acid libraries. We have developed "neurochips" by designing and combining advanced surface chemistries, patterning methods, and high-throughput microfluidics, which can be used to screen for neurotransmitter-specific aptamers in an environment optimized for biorecognition. We have tethered dopamine molecules and employed a previously identified dopamine-specific aptamer as a test to show that our devices are functional. Furthermore, using pre-functionalized neurotransmitter-tethered molecules, we fabricated multiplexed substrates having the capacity to capture and to sort different neurotransmitter-specific aptamers while simultaneously measuring in situ binding affinities. This platform to identify aptamers targeting neurotransmitters will not only enable significant steps toward understanding chemical neurotransmission but will serve to identify other biomolecules important in brain disorders and their treatment.


Tuesday 15 March 2016, 5 PM
American Chemical Society Meeting, Spring 2016, UCLA Showcase, Sunday 13 - Thursday 17 March 2016, San Diego, CA

Elucidating the Mechanism behind Spin-Dependent Charge Transport through DNA Monolayers
John M. Abendroth and Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry and Biochemistry and Materials Science and Engineering, UCLA, Los Angeles, CA 90095, USA

The possibility of selectively filtering electrons with a particular spin by chiral molecules at metal-molecule interfaces without the use of a permanent magnet has stimulated renewed interest in probing spin-dependent phenomena in adsorbed chiral molecules and assemblies. In particular, unprecedented spin selective electron transmission at room temperature has been observed through self assembled monolayers of double-stranded DNA. These surprising results demonstrate the unique and exciting potential to utilize a more versatile class of materials to combine the fields of spintronics, bioelectronics, and biomagnetics. However, the mechanism governing electron spin filtering by DNA remains elusive. Thus, we combine advanced surface chemistry with novel electrochemical characterization strategies to deconvolute the relative contributions of molecular, surface, and interface properties to spin-selective electron conduction through DNA monolayers adsorbed on ferromagnetic substrates. We probe molecular structure and substrate parameters that have been theoretically predicted to influence spin polarization such as molecular length and substrate spin-orbit coupling. Understanding the mechanism responsible for this spin-dependent effect is critical to assess the viability of implementing DNA assemblies as sources of polarized electrons in organic spintronics devices, and advancing the frontiers of room temperature spin-dependent transport.


Wednesday 16 March 2016, 1130 AM
American Chemical Society Meeting, Spring 2016, Surface Characterization & Manipulation for Electronic Applications Symposium, Sunday 13 - Thursday 17 March 2016, San Diego, CA

Precious poison: The self-assembly of cyanide on Au{111}
Andrew Guttentag1, Tobias Wächter2, Kristopher Barr1, John Abendroth1, Tze-Bin Song3, Yang Yang3, David L. Allara4, Michael Zharnikov2, and Paul S. Weiss1

1California NanoSystems Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095, United States
2Applied Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany
3Department of Material Science and Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
4Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States

A vibronic resonance between Au{111} surface states and adsorbed CN vibrations has been predicted, which we target for study. We have formed stable monolayers of cyanide on Au{111} and observe a hexagonal close-packed lattice with a nearest neighbor distance of 3.8±0.5 Å. Cyanide orients normal to the surface attached via a Au-C bond. We show that the substrate-molecule coupling is particularly strong, leading to fast electron transfer from the cyanide molecules to the Au{111} substrate as measured by resonant Auger spectroscopy using the core hole clock method. The CN/Au{111} system is a simple example of a strongly interacting adsorbate-substrate system and will be the subject of a number of further studies to be discussed.


Wednesday 16 March 2016, 810 AM, Bay Room – Wyndham San Diego Bayfront
American Chemical Society Meeting, Spring 2016, Chemical Imaging: Applications, Advances, and Challenges Symposium, Sunday 13 - Thursday 17 March 2016, San Diego, CA

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Thursday 17 March 2016, 800 AM
American Chemical Society Meeting, Spring 2016, Sunday 13 - Thursday 17 March 2016, San Diego, CA

Chemical Lift-Off Lithography
Liane Slaughter, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Tuesday 24 March 2016
The First Middle-Eastern Materials Science Conference, NYU Abu Dhabi

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

We use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to explore the ultimate limits of miniaturization. We direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules [1–3]. Interactions within and between molecules can be designed, directed, measured, understood, and exploited at unprecedented scales. Such interactions can be used to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. We selectively test hypothesized mechanisms of function by varying molecular design, chemical environment, and measurement conditions to enable or to disable function and control using predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule/assembly measurements in order to develop sufficiently significant statistical distributions, while retaining the heterogeneity intrinsic in the measurements. We use a number of excitation mechanisms to induce changes in the molecules and assemblies, including electric field, light, electrochemical potential, ion binding, and chemistry [1-4]. We measure the electronic coupling of the contacts between the molecules and substrates by measuring the polarizabilities of the connected functional molecules [4]. We have likewise developed and applied the means to map buried chemical functionality and interactions [5,6]. The next steps are to learn to assemble and to operate molecules together, both cooperatively and hierarchically, in analogy to biological muscles. We discuss our initial efforts in this area, in which we find both interferences and cooperativity [2].

References
[1] S. A. Claridge, J. J. Schwartz, P. S. Weiss, ACS Nano, 2011, 5, 693-729.
[2] Y. B. Zheng, B. K. Pathem, J. N. Hohman, J. C. Thomas, M. H. Kim, P. S. Weiss, Adv. Matl., 2013, 25, 302-312.
[3] S. A. Claridge, W.-S. Liao, J. C. Thomas, Y. Zhao, H. Cao, S. Cheunkar, A. C. Serino, A. M. Andrews, P. S. Weiss, Chem. Soc. Rev., 2013, 42, 2725-2745.
[4] A. M. Moore, S. Yeganeh, Y. Yao, J. M. Tour, M. A. Ratner, P. S. Weiss, ACS Nano, 2010, 4, 7630-7636.
[5] P. Han, A. R. Kurland, A. N. Giordano, S. U. Nanayakkara, M. M. Blake, C. M. Pochas, P. S. Weiss, ACS Nano, 2009, 3, 3115-3121.
[6] J. C. Thomas, J. J. Schwartz, J. N. Hohman, S. A. Claridge, A. C. Serino, H. S. Auluck, G. Tran, K. F. Kelly, C. A. Mirkin, J. Gilles, S. J. Osher, P. S. Weiss, ACS Nano, 2015, 9, 4734-4742.


Thursday 31 March 2016
Hope College, Department of Chemistry, Neckers Lectures, Holland, MI, USA

Exploring the Ultimate Limits of Miniaturization in Science, Engineering, and Medicine
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Friday 1 April 2016
Hope College, Department of Chemistry, Neckers Lectures, Holland, MI, USA

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

We use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to explore the ultimate limits of miniaturization. We direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules [1-4]. Interactions within and between molecules can be designed, directed, measured, understood, and exploited at unprecedented scales. Such interactions can be used to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. We selectively test hypothesized mechanisms of function by varying molecular design, chemical environment, and measurement conditions to enable or to disable function and control using predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule/assembly measurements in order to develop sufficiently significant statistical distributions, while retaining the heterogeneity intrinsic in the measurements. We use a number of excitation mechanisms to induce changes in the molecules and assemblies, including electric field, light, electrochemical potential, ion binding, and chemistry [1-5]. We measure the electronic coupling of the contacts between the molecules and substrates by measuring the polarizabilities of the connected functional molecules [5]. We have likewise developed and applied the means to map buried chemical functionality and interactions [6,7]. The next steps are to learn to assemble and to operate molecules together, both cooperatively and hierarchically, in analogy to biological muscles. We discuss our initial efforts in this area, in which we find both interferences and cooperativity [2].

References
[1] S. A. Claridge, J. J. Schwartz, P. S. Weiss, ACS Nano 2011, 5, 693-729.
[2] Y. B. Zheng, B. K. Pathem, J. N. Hohman, J. C. Thomas, M. H. Kim, P. S. Weiss, Adv. Matl. 2013, 25, 302-312.
[3] S. A. Claridge, W.-S. Liao, J. C. Thomas, Y. Zhao, H. Cao, S. Cheunkar, A. C. Serino, A. M. Andrews, P. S. Weiss, Chem. Soc. Rev. 2013, 42, 2725-2745.
[4] J. M. Abendroth, O. S. Bushuyev, P. S. Weiss, and C. J. Barrett, ACS Nano 2015, 9, 7746-7768.
[5] A. M. Moore, S. Yeganeh, Y. Yao, J. M. Tour, M. A. Ratner, P. S. Weiss, ACS Nano 2010, 4, 7630-7636.
[6] P. Han, A. R. Kurland, A. N. Giordano, S. U. Nanayakkara, M. M. Blake, C. M. Pochas, P. S. Weiss, ACS Nano 2009, 3, 3115-3121.
[7] J. C. Thomas, J. J. Schwartz, J. N. Hohman, S. A. Claridge, A. C. Serino, H. S. Auluck, G. Tran, K. F. Kelly, C. A. Mirkin, J. Gilles, S. J. Osher, P. S. Weiss, ACS Nano, 2015 9, 4734-4742.


Tuesday 5 April 2016
Technische Universität Wien, Department of Physics Seminar, Vienna, Austria

Atomically Precise Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Wednesday 6 April 2016, 550 PM
Nanoscience with Nanocrystals, NaNaX 7, Marburg, Germany, Monday 4 - Thursday 7 April 2016

Electronic Structure, Assembly, and Chemistry of Precise Clusters
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

Precise clusters offer a new set of building blocks with unique properties that can be leveraged both individually and in materials in which their coupling can be controlled by choice of linker, dimensionality, and structure. Initial measurements in both of these worlds have been made. Isolated adsorbed or tethered clusters are probed with low-temperature scanning tunneling microscopy and spectroscopy. Even closely related elements behave differently on identical substrates. Surprising spectral variations are found for repeated measurements of single isolated, tethered clusters. In periodic solids, precise clusters joined by linkers can be measured experimentally and treated theoretically with excellent agreement, in part due to the relatively weak coupling of the clusters. This coupling can be controlled and exploited to produce materials with tailored properties. Some of the rules for predicting these properties are being developed through these initial studies and the limit to which they can be applied is being explored.


Monday 11 April 2016
Elementary Processes in Molecular Switches at Surfaces, Berlin, Germany, Monday 11 - Wednesday 13 April 2016

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

We use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to explore the ultimate limits of miniaturization. We direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules [1-4]. Interactions within and between molecules can be designed, directed, measured, understood, and exploited at unprecedented scales. Such interactions can be used to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. We selectively test hypothesized mechanisms of function by varying molecular design, chemical environment, and measurement conditions to enable or to disable function and control using predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule/assembly measurements in order to develop sufficiently significant statistical distributions, while retaining the heterogeneity intrinsic in the measurements. We use a number of excitation mechanisms to induce changes in the molecules and assemblies, including electric field, light, electrochemical potential, ion binding, and chemistry [1-5]. We measure the electronic coupling of the contacts between the molecules and substrates by measuring the polarizabilities of the connected functional molecules [5]. We have likewise developed and applied the means to map buried chemical functionality and interactions [6,7]. The next steps are to learn to assemble and to operate molecules together, both cooperatively and hierarchically, in analogy to biological muscles. We discuss our initial efforts in this area, in which we find both interferences and cooperativity [2].

References
[1] S. A. Claridge, J. J. Schwartz, P. S. Weiss, ACS Nano, 2011, 5, 693-729.
[2] Y. B. Zheng, B. K. Pathem, J. N. Hohman, J. C. Thomas, M. H. Kim, P. S. Weiss, Adv. Matl., 2013, 25, 302-312.
[3] S. A. Claridge, W.-S. Liao, J. C. Thomas, Y. Zhao, H. Cao, S. Cheunkar, A. C. Serino, A. M. Andrews, P. S. Weiss, Chem. Soc. Rev., 2013, 42, 2725-2745.
[4] J. M. Abendroth, O. S. Bushuyev, P. S. Weiss, and C. J. Barrett, ACS Nano, 2015, 9, 7746-7768.
[5] A. M. Moore, S. Yeganeh, Y. Yao, J. M. Tour, M. A. Ratner, P. S. Weiss, ACS Nano, 2010, 4, 7630-7636.
[6] P. Han, A. R. Kurland, A. N. Giordano, S. U. Nanayakkara, M. M. Blake, C. M. Pochas, P. S. Weiss, ACS Nano, 2009, 3, 3115-3121.
[7] J. C. Thomas, J. J. Schwartz, J. N. Hohman, S. A. Claridge, A. C. Serino, H. S. Auluck, G. Tran, K. F. Kelly, C. A. Mirkin, J. Gilles, S. J. Osher, P. S. Weiss, ACS Nano, 2015, 9, 4734-4742.


Wednesday 20 April 2016
Vanderbilt University, VINSE Seminar, Nashville, TN, USA

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The chemical, physical, and electronic connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important role that chemistry can play in making and optimizing precise contacts that preserve key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory.


Wednesday 27 April 2016, 10 AM
Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany
CFEL Seminar room IV, O1.111 (Bldg. 99)

What's on The Outside Counts Too: Surface-Dipole Modulated Assembly
Jeffrey Schwartz, California NanoSystems Institute and Department of Physics, UCLA, Los Angeles, CA 90095, USA

Detailed understanding and control of the intermolecular forces that govern molecular assembly are necessary to engineer structure and function at the nanoscale.

Liquid crystal (LC) assembly is exceptionally sensitive to surface properties, capable of transducing nanoscale intermolecular interactions into a macroscopic optical readout. Selfassembled monolayers (SAMs) modify surface interactions and are known to influence LC alignment. Here, we exploit the different dipole magnitudes and orientations of carboranethiol and dithiol positional isomers to deconvolve the influence of SAM-LC dipolar coupling from variations in molecular geometry, tilt, and order. Director orientations and anchoring energies are measured for LC cells employing various carboranethiol and dithiol isomer alignment layers. The normal component of the molecular dipole in the SAM, toward or away from the underlying substrate, was found to determine the in-plane LC director orientation relative to the anisotropy axis of the surface. By using LC alignment as a probe of interaction strength, we elucidate the role of dipolar coupling of molecular monolayers to their environment in determining molecular orientations.

We apply this understanding to advance the engineering of molecular interactions at the nanoscale.


Thursday 28 April 2016, 12 noon
University of Wisconsin, Department of Radiology Grand Rounds, Madison, WI

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function.1 New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.

1Electrons, Photons, and Force: Quantitative Single-Molecule Measurements from Physics to Biology, S. A. Claridge, J. J. Schwartz, and P. S. Weiss, ACS Nano 5, 693 (2011).


Friday 29 April 2016
University of Wisconsin, Department of Chemistry, Madison, WI

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The chemical, physical, and electronic connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important role that chemistry can play in making and optimizing precise contacts that preserve key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory.


Monday 2 May 2016, 12 noon
UCLA, Department of Chemistry, Los Angeles, USA

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The chemical, physical, and electronic connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important role that chemistry can play in making and optimizing precise contacts that preserve key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory.


Wednesday 4 May 2016
University of California, San Diego, Department of Physics Colloquium, La Jolla, CA, USA

Atomically Precise Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Wednesday 11 May 2016, 345 PM, Planetarium
California State University at Northridge, Departments of Chemistry and Physics, Northridge, CA, USA

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The chemical, physical, and electronic connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important role that chemistry can play in making and optimizing precise contacts that preserve key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory.


Thursday 19 May 2016, 11 AM, USDA Conference & Training Center, Patriots Plaza III, 355 E Street, SW, Washington, DC 20024
2016 National Nanotechnology Initiative (NNI) Strategic Planning Stakeholder Workshop, Washington, DC, USA

Spotlight on Nanotechnology in the Physical Sciences
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Tuesday 25 May 2016
UCLA Undergraduate Research Poster Day, UCLA, Los Angeles, CA, USA

Principles of Principals in Image Processing
Mercedes B. Cornelius, Miles A. Silverman, and Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

Single-molecule measurements of complex biological structures, such as proteins, are an attractive route for determining structures of important biomolecules that are difficult to analyze through conventional techniques. Using a custom-built alternating current scanning tunneling microscope we have imaged self-assembled peptide structures on graphite surfaces in both topography and microwave polarizability modes. Here, these images are analyzed to identify distinct characteristics, structures, and features of peptides at the single-molecule level. Utilizing mathematical techniques, such as two-dimensional variational mode decomposition, we are able to both segment images into domains of different structures and to identify unique structural motifs within those domains. We have been able to display principal characteristics of the two modes of the image via principal component analysis. We are working to distinguish between amino acid side chains based on differential polarizabilities characteristics of the images. Ultimately, by observing the structures of proteins at the single-molecule level, we gain insight into molecules that are otherwise extremely difficult to study. Understanding the structures of molecules, such as amyloids, allows us to evaluate disease-related proteins and to elucidate their roles in neurodegenerative diseases. Mathematical modeling and segmentation enables us to extract and analyze relevant data from a complicated system and to elucidate the structures of proteins self-assembled onto surfaces.


Tuesday 25 May 2016
UCLA Undergraduate Research Poster Day, UCLA, Los Angeles, CA, USA

Determination of Structural Organization and Morphology of Amyloid Beta via Scanning Tunneling Microscopy
Diana Yugay, Lisa M. Kawakami, Dominic Goronzy, Jerome Gilles, Tze-Bin Song, Yang Yang, Ya-Hong Xie, and Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

Alzheimer's Disease (AD) is a chronic neurodegenerative disease that involves the aggregation of amyloid beta (AB) peptides in the brain. Transition metal ions, such as Cu(II) and Zn(II), are known to be abnormally concentrated in AB aggregates and synaptic areas of the brain in people with AD. A cure for AD has yet to be discovered due to the limited knowledge about cause and effect in the disease, which may involve the binding of transition metal ions to AB; thus, elucidating amino acid coordination at the binding site(s) is an important step in understanding the disease. Previously, we have demonstrated the ability to resolve sub-molecular structures of biological molecules and differentiate between side chains of individual amino acids and their orientations by using scanning tunneling microscopy (STM). In this study, we report structural elucidation of the N-terminus of AB (AB(1-16)) via STM and its structural progression in the presence and the absence of Cu(II) ions via circular dichroism, atomic force microscopy, surface-enhanced Raman spectroscopy, and cyclic voltammetry. Our findings indicate that upon the deposition of AB(1-16) on highly oriented pyrolytic graphite, AB(1-16) laminates into structured B-sheet domains. Most importantly, based on the analysis of the length and position of protruding features of Cu(II) ions within AB(1-16) peptides from STM images, we determine that Cu(II) ions participate in inter-sheet AB(1-16) binding by coordinating with two neighboring histidine residues, His13 and His14.


Friday 28 May 2016, 10 AM
7th International Symposium on Bioanalysis, Biomedical Engineering and Nanotechnology (7th ISBBN 2016), Hunan University, Changsha, China, Thursday 27 - Saturday 29 May 2016

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function.1 New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples related to the BRAIN2 and Microbiome3 Initiatives will be discussed.

1Electrons, Photons, and Force: Quantitative Single-Molecule Measurements from Physics to Biology, S. A. Claridge, J. J. Schwartz, and P. S. Weiss, ACS Nano 5, 693 (2011).
2Nanotools for Neuroscience and Brain Activity Mapping, A. P. Alivisatos, A. M. Andrews, E. S. Boyden, M. Chun, G. M. Church, K. Deisseroth, J. P. Donoghue, S. E. Fraser, J. Lippincott-Schwartz, L. L. Looger, S. Masmanidis, P. L. McEuen, A. V. Nurmikko, H. Park, D. S. Peterka, C. Reid, M. L. Roukes, A. Scherer, T. J. Sejnowski, K. L. Shepard, D. Tsao, G. Turrigiano, P. S. Weiss, C. Xu, R. Yuste, and X. Zhuang, ACS Nano 7, 1850 (2013).
3Tools for the Microbiome: Nano and Beyond, J. S. Biteen, P. C. Blainey, M. Chun, G. M. Church, P. C. Dorrestein, S. E. Fraser, J. A. Gilbert, J. K. Jansson, R. Knight, J. F. Miller, A. Ozcan, K. A. Prather, E. G. Ruby, P. A. Silver, S. Taha, G. van den Engh, P. S. Weiss, G. C. L. Wong, A. T. Wright, and T. D. Young, ACS Nano 10, 6 (2016).


Friday 4 June 2016, 8 AM
Nanotoxicology, Boston, MA, USA

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Thursday 16 June 2016, 330 PM, Moss Auditorium, A2-342 Marion Davies Childrens Clinic, UCLA, Los Angeles, CA
Developmental Hematology Training Program Pediatric Hematology/Oncology Fellow Presentations, Telluride, Monday 27 June - Friday 1 July 2016

Multifaceted Nanobiomaterial Assemblies for Modeling Hematopoietic Stem Cell Niches
Steven Jonas, California NanoSystems Institute and Department of Pediatrics, UCLA, Los Angeles, CA 90095


Tuesday 28 June 2016, 9 AM
Electronic and Magnetic Properties of Chiral Structures and their Assemblies, Telluride, Monday 27 June - Friday 1 July 2016

Base Sequence and Structure Relationships in Spin Polarization by DNA
John M. Abendroth and Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Wednesday 29 June 2016
Electronic and Magnetic Properties of Chiral Structures and their Assemblies, Telluride, Monday 27 June - Friday 1 July 2016

Spin-Dependent Electrochemistry of Perylenediimide Derivatives Noncovalently Assembled within DNA
John M. Abendroth and Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Wednesday 6 July 2016, 12 noon
UCLA Lunchtime Young Researcher Seminar Series, 2033 Young Hall

Spin-Dependent Charge Transport through Chiral Molecular Monolayers
John M. Abendroth, California NanoSystems Institute and Departments of Chemistry & Biochemistry, UCLA, Los Angeles, CA 90095


Friday 15 July 2016, 9 AM
International Conference on Chemical Bonding, Thursday 14 - Monday 18 July 2016

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The chemical, physical, and electronic connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important role that chemistry can play in making and optimizing precise contacts that preserve key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory.


Wednesday 20 July 2016, 10 AM, CNSI Auditorium, UCLA
UCLA CSST Seminar

A Career in Nanoscience So Far
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Wednesday 20 July 2016, 12 noon, 2033 Young Hall, UCLA
UCLA Lunchtime Young Researcher Seminar Series

DNA Aptamer Biosensors to Monitor Neurotransmitters in the Brain
Nako Nakatsuka, California NanoSystems Institute and Departments of Chemistry & Biochemistry, UCLA, Los Angeles, CA 90095


Tuesday 2 August 2016, 120 PM, Fusion Hall, KI Building, KAIST, Daejeon, Korea
Big Ideas in Emerging Materials, KAIST, Daejeon, Korea, 2 August 2016

Atomically Precise Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Wednesday 3 August 2016
Ulsan National Institute of Science and Technology (UNIST), Department of Chemistry, Ulsan, Korea

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Wednesday 10 August 2016, 12 noon, 2033 Young Hall, UCLA
UCLA Lunchtime Young Researcher Seminar Series

Transition Metal Ion Binding in Amyloid Peptides
Diana Yugay, California NanoSystems Institute and Departments of Chemistry & Biochemistry, UCLA, Los Angeles, CA 90095


Monday 22 August 2016, 8 AM, Ormandy West Room, Doubletree Hotel, Philadelphia
ACS National Meeting, Biological Imaging Symposium, Philadelphia, PA, Sunday 21 - Thursday 25 August 2016

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Tuesday 23 August 2016, 930 AM, Room 115B Pennsylvania Convention Center
ACS National Meeting, Ray Schaak Award Symposium, Philadelphia, PA, Sunday 21 - Thursday 25 August 2016

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The chemical, physical, and electronic connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important role that chemistry can play in making and optimizing precise contacts that preserve key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory.


Wednesday 6 September 2016, 2 PM, CNSI, UCLA
UCLA CSST Program

Self-Assembly of Carboxy-Functionalized Carboranethiols on Au{111}
Jun She, Dominic Goronzy, and Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Friday 16 September 2016
Arizona State University, Department of Materials Science and Engineering, Tempe, AZ

Atomically Precise Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Sunday 25 - Thursday 29 September 2016
Brazilian Materials Research Society Meeting, Sunday 25 - Thursday 29 September 2016

Atomically Precise Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Tuesday 11 October 2016
MANA, NIMS, Tsukuba, Japan

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

We use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to explore the ultimate limits of miniaturization. We direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood, and exploited at unprecedented scales. Such interactions can be used to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. We selectively test hypothesized mechanisms of function by varying molecular design, chemical environment, and measurement conditions to enable or to disable function and control using predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule/assembly measurements in order to develop sufficiently significant statistical distributions, while retaining the heterogeneity intrinsic in the measurements. We use a number of excitation mechanisms to induce changes in the molecules and assemblies, including electric field, light, electrochemical potential, ion binding, and chemistry. We measure the electronic coupling of the contacts between the molecules and substrates by measuring the polarizabilities of the connected functional molecules. We have likewise developed and applied the means to map buried chemical functionality and interactions. The next steps are to learn to assemble and to operate molecules together, both cooperatively and hierarchically, in analogy to biological muscles. We discuss our initial efforts in this area, in which we find both interferences and cooperativity.


Wednesday 12 October 2016, 9 AM
AsiaNano 2016, Sapporo, Japan, 10-13 October 2016

Atomically Precise Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Friday 14 October 2016, 210 PM
RIKEN Centennial Project: RIKEN-MANA/NIMS Joint Symposium of Advanced Science and Technology, Akiba Plaza, 6F Seminar Room 1, Akihabara, Tokyo, Japan

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Wednesday 19 October 2016
China Nanomedicine, Wuhan, China, 19-21 October 2016

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function [1]. New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed [2]. Other advances from this area have led to the development multiplexed nanobiosensor arrays that technologically underpin and enable key measurements the BRAIN and microbiome initiatives [3,4].

References
[1] Claridge SA, et al. Electrons, Photons, and Force: Quantitative Single-Molecule Measurements from Physics to Biology, ACS Nano 2011, 5:693-729.
[2] Yugay D, et al. Copper Ion Binding Site in β-Amyloid Peptide. Nano Letters 2016, 16, in press and ASAP. DOI: 10.1021/acs.nanolett.6b02590
[3] Alivisatos AP, et al. Nanotools for Neuroscience and Brain Activity Mapping. ACS Nano 2013, 7:1850-1866.
[4] Biteen JS, et al. Tools for the Microbiome: Nano and Beyond. ACS Nano 2016, 10, 6-37.


Friday 21 October 2016, 1230 PM
American University Beirut, Makhlouf Haddadin Symposium Beirut, Lebanon, 20-21 October 2016

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Tuesday 25 October 2016, 930 AM
International Conference on Self-Assembly in Confined Spaces, San Sebastian, Spain, 25-27 October 2016

Chemistry and Function in Confined Spaces
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

We have developed insertion-directed assembly on surfaces in order to place functional molecules, switches and motors, into well-defined environments [1-3]. We design the matrices to interact with and to guide the molecules into position or through regioselective reactions [4]. We have developed simple, symmetric molecules for use as the components of the two-dimensional matrices so that both the confined spaces and intermolecular interactions are increasingly well defined. While much of our work has been done on flat surfaces where we get better than molecular resolution of the position and orientation of each molecule using scanning tunneling microscopy and spectroscopy, I will discuss how we are porting these same ideas over to curved and inaccessible surfaces [5]. I will also discuss new strategies for isolation, as well as how the structures that we assemble can be used to develop nanobiosensor arrays to measure the chemical signaling molecules of the brain and of the microbiome.

Keywords: nanoscience, self-assembly, cage molecules.

References
[1] S. A. Claridge, W.-S. Liao, J. C. Thomas, Y. Zhao, H. Cao, S. Cheunkar, A. C. Serino, A. M. Andrews, P. S. Weiss, Chemical Society Reviews, 2013, 42, 2725.
[2] B. K. Pathem, S. A. Claridge, Y. B. Zheng, P. S. Weiss, Annual Review of Physical Chemistry, 2013, 64, 605.
[3] Y. B. Zheng, B. K. Pathem, J. N. Hohman, M. H. Kim, P. S. Weiss, Advanced Materials, 2013, 25, 302.
[4] M. H. Kim, J. N. Hohman, Y. Cao, K. N. Houk, H. Ma, A. K.-Y. Jen, P. S. Weiss, Science, 2011, 331, 1312.
[5] A. Y. B. Zheng, J. L. Payton, T.-B. Song, B. K. Pathem, Y. Zhao, H. Ma, Y. Yang, L. Jensen, A. K.-Y. Jen, P. S. Weiss, J. Public, Nano Letters, 2012, 12, 5362.


Wednesday 26 October 2016, 12 noon
CIC nanoGune Physics Colloquium, San Sebastian, Spain, 25-27 October 2016

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Thursday 3 November 2016, 1 PM
CTO Summit | Rethink Disruption: Emerging Technologies Transforming Business and Society, Ritz Carlton, Half Moon Bay, CA

The Future of Nano
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Monday 7 November 2016, 11 AM
NSF Workshop on Mid-Scale Instrument Development

New Tools Lead to New Science: Challenges in Instrument Development
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Wednesday 9 November 2016
MIT Micro-Nano Seminar Series, Cambridge, MA

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Saturday 12 November 2016, 11 AM - 1 PM, 2:50 PM - 3:30 PM, California NanoSystems Institute
2016 Seaborg Symposium Poster Session, University of California, Los Angeles, Los Angeles, CA

Monitoring Spin Selectivity in DNA-Mediated Charge Transfer using Fluorescence Microscopy
Poster Award Winner!

John M. Abendroth, Nako Nakatsuka, Dokyun Kim, Eric E. Fullerton, Anne M. Andrews, and Paul S. Weiss
California NanoSystems Institute and Departments of Chemistry and Biochemistry and Materials Science and Engineering, Department of Psychiatry and Biobehavioral Health, Semel Institute for Neuroscience and Human Behavior, and Hatos Center for Neuropharmacology, UCLA
Center for Memory and Recording Research, UCSD

The possibility of selectively filtering electrons with a particular spin by chiral molecules at metal-molecule interfaces without the use of a permanent magnet has stimulated renewed interest in probing spin-dependent phenomena in adsorbed chiral molecules and assemblies.1-4 We measured the spin‑filtering efficiency of self-assembled monolayers of helical, double-stranded DNA on multilayer substrates that possess perpendicular magnetic anisotropy, enabling the injection of spin-polarized electrons into the DNA monolayers. The spin-filtering phenomenon was monitored using fluorescence microscopy and by taking advantage of the optical properties of water-soluble perylenediimide derivatives that noncovalently and precisely assemble within double-stranded DNA. Fluorescence quenching of the photoexcited dye molecules is dependent upon the efficiency of DNA-mediated charge transfer to metal surfaces, which can be modulated with an external magnetic field used to polarize the spins within the multilayer substrates. Controlling spin transport with light in this manner opens up new opportunities to design device architectures that utilize chiral organic species to generate and to manipulate spin-polarized currents.5,6 Current and future work will develop fundamental understanding of molecular parameters such as sequence and length that influence the spin-filtering effect.


Saturday 12 November 2016, 11 AM - 1 PM, 2:50 PM - 3:30 PM, California NanoSystems Institute
2016 Seaborg Symposium Poster Session, University of California, Los Angeles, Los Angeles, CA

Towards Nanoscale Biosensors to Map Signaling Molecules to Understand Brain Activity

Nako Nakatsuka, Kyung-Ae Yang, You Seung Rim, Xiaobin Xu, John M. Abendroth, Chuanzhen Zhao, Yang Yang, Milan Stojanovic, Paul S. Weiss, and Anne M. Andrews
California NanoSystems Institute and Departments of Chemistry and Biochemistry and Materials Science and Engineering, Department of Psychiatry and Biobehavioral Health, Semel Institute for Neuroscience and Human Behavior, and Hatos Center for Neuropharmacology, UCLA
Division of Experimental Therapeutics, Department of Medicine, and Department of Bioengineering, Columbia University

At its essence, brain function relies on complex extracellular chemistries between small molecule neurochemicals for information encoding. Investigating these interactions in real-time at the spatiotemporal level of neural circuits and across diverse signaling molecules necessitates the design, development, fabrication and validation of next generation in vivo biosensors. We couple the molecular recognition properties of rationally designed, chemically synthesized DNA sequences termed aptamers with direct signal detection via field-effect transistors. Aptamers can be optimized for a range of target concentrations, signal transduction, response speed, and in vivo stability. Dynamic changes in neurotransmitter concentrations are transduced into electrical signals by optimized binding-induced aptamer conformation changes that alter electric fields in close proximity to the sensor surfaces. We have tested the functionality of serotonin and dopamine specific aptamer field-effect transistors, which have shown high sensitivity with a limit of detection of ten femtomolar, approximately six orders of magnitude lower than the dissociation constant of the artificial recognition elements. These devices retain their functionality in full ionic strength biological fluids including undiluted artificial cerebrospinal fluid. We are now conducting measurements ex vivo in brain tissue homogenates derived from mice that lack serotonin to test device response upon controlled addition of serotonin while also assessing biofouling of devices. We envision highly multiplexed arrays of nanoscale sensors fabricated on the surfaces of implantable microprobes that will enable large-scale functional mapping of brain activity.


Saturday 12 November 2016, 435 PM
Craniomaxillofacial Disorders and Solutions in Man and Animals, Luskin Conference Center, UCLA, Los Angeles, CA, Friday 11 - Sunday 13 November 2016

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Wednesday 30 November 2016, 1 PM
UCLA Department of Bioengineering

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Saturday 10 December 2016
The Fourth Annual Conference of the Chinese Society of Micro- and Nanoscience and Technology and the 2016 International Conference on Nanobiology and Nanomedicine, Wednesday 17 - Saturday 10 December 2016

The Next Decade of Nanoscience and Nanotechnology
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Wednesday 14 December 2016
International Chemistry Conference, Singapore, Sunday 11 - Wednesday 14 December 2016

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Thursday 19 January 2017, 430 PM
ONR Biofilms Program Review, Gaylord Conference Center, National Harbor, MD, USA, 17-20 January 2017

Electrogenic Biofilms
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA


Monday 27 February 2017, 235 PM
11th Annual Symposium on Nanobiotechnology: Frontiers in Nanobiology and Nanomedicine, Tokyo, Japan, 27-28 February 2017

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to imaging and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Monday 6 March 2017, 5 PM
5th International Conference on Multifunctional, Hybrid and Nanomaterials, Lisbon, Portugal, Monday 6 - Friday 10 March 2017
Sympsoium A: Biohybrids, Biomaterials, and Biological Materials

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to sensing, imaging, and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include using biomolecular recognition in sensor arrays to probe dynamic chemistry in the brain and microbiome systems. It also includes fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Sunday 2 April 2017, 905 AM, Union Square 19/20 - Hilton San Francisco Union Square
Spring 2017 National ACS Meeting, San Francisco, CA, Sunday 2 - Thursday 6 April 2017
Symposium on Analytical Neuroscience

Aptamer field-effect transistors as neurochemical sensors to monitor neurotransmitters in vivo
Nako Nakatsuka2,3, nako.nakatsuka@gmail.com, Kyung-Ae Yang4, You Seung Rim3,5, Xiaobin Xu2, John Abendroth2,3, Chuanzhen Zhao2,3, Yang Yang5, Milan Stojanovic4,6, Paul Weiss2,3, Anne Andrews1
1Department of Psychiatry and Biobehavioral Health and Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, California, United States;
2Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California, United States;
3California NanoSystems Institute, Los Angeles, California, United States;
4Division of Experimental Therapeutics, Department of Medicine, Columbia University, New York, New York, United States;
5Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, California, United States;
6Department of Biomedical Engineering, Columbia University, New York, New York, United States

Investigating brain chemistries in real time at the spatiotemporal level of neural circuits and across diverse signaling molecules necessitates neurochemical biosensors that approach these critical attributes. We couple the molecular recognition properties of rationally designed, chemically synthesized DNA sequences, termed aptamers, with direct signal detection via field-effect transistors. Aptamers can be designed for a range of target detection, signal transduction, response speed, and in vivo stability. Changes in neurotransmitter concentrations can be monitored via optimized binding-induced aptamer conformation changes that are transduced into electrical signals. Reversible binding of target neurotransmitters such as serotonin and dopamine by specific aptamers are hypothesized to shift electric potentials in close proximity to FET surfaces, resulting in conductance changes. Serotonin- and dopamine-specific aptamer field-effect transistors have high sensitivity with a limit of detection of 10 fM, approximately six orders of magnitude lower than the dissociation constant of the artificial recognition elements. These devices retain their functionality in full ionic strength biological fluids including artificial cerebrospinal fluid. We are now conducting measurements ex vivo in brain tissue homogenates of Tph2 knockout mice that lack serotonin to test device response upon controlled addition of serotonin while assessing biofouling of devices. We envision unprecedented capacity to measure neurochemical signaling directly, in vivo, and in real time, which will impact our understanding of brain function in relation to complex behaviors.


Sunday 2 April 2017, 6 PM, Halls B/C - Moscone Center
Spring 2017 National ACS Meeting, San Francisco, CA, Sunday 2 - Thursday 6 April 2017
Symposium on Fundamental Research in Colloids, Surfaces & Nanomaterials

Proposing a two-molecule multiplexed neuromorphic system: The first step towards a chemically based artificial brain
Nako Nakatsuka1,3, Chuanzhen Zhao1,2, John Abendroth1,2, Huajun Chen2,4, Kevin Cheung1,2, Stemer Dominik2,4, Leonardo Scarabelli1,2, scarabelli.leonardo@gmail.com, Kyung-Ae Yang5, Bowen Zhu2,4, Hongyan Yang3, Yang Yang2,4, Milan Stojanovic5,6, Paul Weiss1,2, Anne Andrews2,3
1Chemistry & Biochemistry, University of California Los Angeles, Los Angeles, California, United States;
2California NanoSystems Institute, University of California Los Angeles, Los Angeles, California, United States;
3Department of Psychiatry & Behavioral Health, University of California Los Angeles, Los Angeles, California, United States;
4Department of Materials Science & Engineering, University of California Los Angeles, Los Angeles, California, United States;
5Division of Experimental Therapeutics, Department of Medicine, Columbia University, New York, New York, United States;
6Department of Biomedical Engineering, Columbia University, New York, New York, United States

Information acquisition, processing, and storage involving brain neurons consists of electrical and chemical components. While functionally organized micro- and nanostructures have been developed to model electrical aspects of brain neurotransmission, the complexities of chemical transmission cannot be investigated using these structures as yet. Examples of the fabrication of artificial synapses in neuromorphic systems based purely on electronic synapses exploit mechanisms such as fingering via oxide or sulfide reduction. Despite some promising results, these approaches completely overlook the highly multiplexed and heterogeneous chemical networks of neurotransmitter molecules that are fundamental to complex brain function.

We propose a synthetic multi-molecule neuromorphic system, initially employing two native neurotransmitters and related molecules. Our approach is based on state-of-the-art aptamer-based field-effect transistor sensors that have been optimized for responding to specific neurotransmitters. These sensors are placed on the same substrate and are able to work simultaneously and in an interconnected manner with one another, i.e., the concentration of one analyte influences the concentration of the other, consequently altering the responses of the corresponding sensor. This biomolecular analog-to-digital transducer represents a basic working principle behind chemical transmission and information processing in synapses, opening new avenues for the study of brain chemistry, molecular networks, and for introducing native biological strategies to enrich the potential capabilities of neuromorphic computing.


Monday 3 April 2017, 930 AM, Moscone Center, Room 2003
Spring 2017 National ACS Meeting, San Francisco, CA, Sunday 2 - Thursday 6 April 2017
Symposium on Nanoscale Patterning and Characterization

Polymer pen chemical lift-off lithography
Xiaobin Xu1, xxu.uta@gmail.com, Qing Yang1, Kevin Cheung1, Chuanzhen Zhao1, Natcha Wattanatorn1, Jason Belling1, John Abendroth1, Liane Siu Slaughter1, Chad Mirkin4, Anne Andrews1,3, and Paul S. Weiss1,2
1California NanoSystems Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California, United States;
2Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, California, United States;
3Department of Psychiatry and Biobehavioral Health, Semel Institute for Neuroscience and Human Behavior, and Hatos Center for Neuropharmacology, University of California, Los Angles, Los Angeles, California, United States;
4International Institute for Nanotechnology and Department of Chemistry and Materials Science & Engineering, Northwestern University, Evanston, Illinois, United States

We combine chemical lift-off lithography (CLL) with large arrays of polymer pens with sub-20-nm tips, developing polymer pen chemical lift-off lithography (PPCLL). We demonstrated the feasibility of PPCLL with experiments using v-shaped polymer pen arrays and associated simulations. Simulation results show a nanometer-scale quadratic relationship between the contact linewidth and two variables: base linewidth of the polymer pen and vertical compression. We invented a supporting arm system and designed a series of v-shaped polymer pens with known height differences to control precisely the relative vertical position of each polymer pens at sub-20-nm scale, which mimicked a high-precision scanning stage. In this way, we successfully obtained linear array patterns with linewidths from sub-50-nm to sub-500-nm with minimum sub-20-nm linewidth increment tunability. The CLL pattern linewidth perfectly matched the simulations. These results suggest that through the proper design of the supporting arms to suitable positions and the base linewidth of the polymer pen arrays, one can completely eliminate the need for the scanning stage system in PPCLL to increase the throughput and to reduce cost. We also showed that PPCLL can be used to design and to fabricate DNA microarrays efficiently by backfilling the patterns after PPCLL with probe DNA, and subsequently hybridizing with complementary target sequences.


Monday 3 April 2017, 2 PM, Moscone Center, Room 2003
Spring 2017 National ACS Meeting, San Francisco, CA, Sunday 2 - Thursday 6 April 2017
Symposium on Nanoscale Patterning and Characterization

New Dimensions in Patterning: Placement and Metrology of Chemical Functionality at All Scales
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

We place single molecules and assemblies into precisely controlled environments on surfaces. The inserted assemblies and the monolayer matrices that contain them can be designed so as to interact directly, to give stability or other properties to functional supramolecular assemblies. New families of highly symmetric molecules are being developed to yield even greater control and are enabling elucidation of the key design parameters of both the molecules and assemblies. These design elements, in turn, enable controlled chemical patterning from the sub-nanometer to the centimeter scales. We simultaneously develop metrology tools for these methods to give unprecedented insight on the structures, function, and properties of these assemblies.


Monday 3 April 2017, 8 PM, Hall D - Moscone Center
Spring 2017 National ACS Meeting, San Francisco, CA, Sunday 2 - Thursday 6 April 2017
Symposium on Fundamental Research in Colloids, Surfaces & Nanomaterials

Proposing a two-molecule multiplexed neuromorphic system: The first step towards a chemically based artificial brain
Nako Nakatsuka1,3, Chuanzhen Zhao1,2, John Abendroth1,2, Huajun Chen2,4, Kevin Cheung1,2, Stemer Dominik2,4, Leonardo Scarabelli1,2, scarabelli.leonardo@gmail.com, Kyung-Ae Yang5, Bowen Zhu2,4, Hongyan Yang3, Yang Yang2,4, Milan Stojanovic5,6, Paul Weiss1,2, Anne Andrews2,3
1Chemistry & Biochemistry, University of California Los Angeles, Los Angeles, California, United States;
2California NanoSystems Institute, University of California Los Angeles, Los Angeles, California, United States;
3Department of Psychiatry & Behavioral Health, University of California Los Angeles, Los Angeles, California, United States;
4Department of Materials Science & Engineering, University of California Los Angeles, Los Angeles, California, United States;
5Division of Experimental Therapeutics, Department of Medicine, Columbia University, New York, New York, United States;
6Department of Biomedical Engineering, Columbia University, New York, New York, United States

Information acquisition, processing, and storage involving brain neurons consists of electrical and chemical components. While functionally organized micro- and nanostructures have been developed to model electrical aspects of brain neurotransmission, the complexities of chemical transmission cannot be investigated using these structures as yet. Examples of the fabrication of artificial synapses in neuromorphic systems based purely on electronic synapses exploit mechanisms such as fingering via oxide or sulfide reduction. Despite some promising results, these approaches completely overlook the highly multiplexed and heterogeneous chemical networks of neurotransmitter molecules that are fundamental to complex brain function.

We propose a synthetic multi-molecule neuromorphic system, initially employing two native neurotransmitters and related molecules. Our approach is based on state-of-the-art aptamer-based field-effect transistor sensors that have been optimized for responding to specific neurotransmitters. These sensors are placed on the same substrate and are able to work simultaneously and in an interconnected manner with one another, i.e., the concentration of one analyte influences the concentration of the other, consequently altering the responses of the corresponding sensor. This biomolecular analog-to-digital transducer represents a basic working principle behind chemical transmission and information processing in synapses, opening new avenues for the study of brain chemistry, molecular networks, and for introducing native biological strategies to enrich the potential capabilities of neuromorphic computing.


Tuesday 4 April 2017, 2 PM, Moscone Center, Room 2007
Spring 2017 National ACS Meeting, San Francisco, CA, Sunday 2 - Thursday 6 April 2017
Symposium on Deposition & Etching of Nanostructures

Cage Molecule Self-Assembly
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

We have shown that upright, symmetric cage molecules self-assembled on surfaces have simple domain and defect structures. Unlike linear molecules, such as alkanethiols on Au{111}, these cage molecules do not tilt and do not conformationally relax. The lattices of the cage molecules are determined by the projections of the cages on the surface. Thus, different isomers, such as carboranethiols on Au{111}, form identical lattice structures. These monolayers enable key tests of simple phenomena, such as the effects of dipole moment direction and amplitude. For example, molecules with dipoles parallel to the surface form nonpolar monolayers and outcompete molecules with dipoles normal the surface, which form polar monolayers. These properties can be measured both at the macroscopic and nanoscopic scales. We understand the enhanced stability of the nonpolar surfaces to aligned dipoles in the monolayers and set out to measure such effects. Using combinations of spectroscopic imaging and novel image analyses, we find that dipoles do align, even across domain boundaries. We use mixed self-assembled monolayers of carboranes to tune and to optimize the band alignment of organic electronic devices without changing the morphology of the active layer. We also assemble multifunctionalized cage molecules and show that we can protonate and deprotonate thiol(ate)s to change the valency of attachment to the surface through simple reactions.


Wednesday 5 April 2017, 1150 AM, Moscone Center, Room 2010
Spring 2017 National ACS Meeting, San Francisco, CA, Sunday 2 - Thursday 6 April 2017
Symposium on Basic Research in Colloids, Surfactants & Nanomaterials

Spin selectivity in DNA-mediated charge transport: Base sequence and structure relationships
John Abendroth1,2, abend@chem.ucla.edu, Nako Nakatsuka1,2, Matthew Ye1,2, Dokyun Kim4, Eric Fullerton4, Anne Andrews1,3, Paul Weiss1,2
1Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California, United States;
2California NanoSystems Institute, UCLA, Los Angeles, California, United States;
3Department of Psychiatry and Biobehavioral Health, University of California, Los Angeles, Los Angeles, California, United States;
4Center for Memory and Recording Research, University of California, San Diego, San Diego, California, United States

Self-assembled monolayers of chiral molecules on metal and semiconducting surfaces have recently demonstrated the capability to filter transmitted electrons depending on spin orientation and the handedness of the molecules. This phenomenon, termed the chiral-induced spin selectivity effect, has renewed interest in probing spin-dependent phenomena in adsorbed chiral molecules, including self-assembled monolayers of double-stranded DNA. While the factors that affect DNA-mediated charge transfer have been extensively studied, the influence of DNA base sequence, GC content, or helical geometry on the spin selectivity in transmitted electrons has not been systematically investigated. We probed the dependence of spin polarization in DNA-mediated charge transfer on nitrogenous base sequence as a means to study spin selectivity in both coherent tunneling and incoherent hopping of charge carriers through helical molecules. Self-assembled monolayers of DNA with varying sequences were formed on multilayer substrates that possess perpendicular magnetic anisotropy, enabling the injection of spin-polarized electrons into the monolayers. The spin-filtering phenomenon was monitored using fluorescence microscopy and photoelectrochemistry by taking advantage of the optical properties of water-soluble perylenediimide derivatives that noncovalently and precisely assemble within double-stranded DNA. Competing charge-transfer pathways that lead to fluorescence or photocurrent generation following photoexcitation of the dye molecules are dependent upon the efficiency of DNA-mediated charge transfer to metal surfaces. This efficiency can be modulated with an external magnetic field used to polarize the spins within the multilayer substrates. Controlling spin transport with light in this manner opens up new opportunities to design device architectures that utilize chiral organic species to generate and to manipulate spin-polarized currents.


Wednesday 12 April 2017
IEEE-NEMS 2017, 12th Annual IEEE International Conference on Nano/MicroEngineered and Molecular Systems, UCLA, Los Angeles, CA, Sunday 9 - Wednesday 12 April 2017
Symposium on Nano-Energy: Materials and Transport

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

We use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to explore the ultimate limits of miniaturization. We direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood, and exploited at unprecedented scales. Such interactions can be used to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. We selectively test hypothesized mechanisms of function by varying molecular design, chemical environment, and measurement conditions to enable or to disable function and control using predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule/assembly measurements in order to develop sufficiently significant statistical distributions, while retaining the heterogeneity intrinsic in the measurements. We use a number of excitation mechanisms to induce changes in the molecules and assemblies, including electric field, light, electrochemical potential, ion binding, and chemistry. We measure the electronic coupling of the contacts between the molecules and substrates by measuring the polarizabilities of the connected functional molecules. We have likewise developed and applied the means to map buried chemical functionality and interactions. The next steps are to learn to assemble and to operate molecules together, both cooperatively and hierarchically, in analogy to biological muscles. We discuss our initial efforts in this area, in which we find both interferences and cooperativity.


Tuesday 18 April 2017, 2 PM
Spring MRS Meeting, Phoenix, AZ, Monnday 17 - Friday 21 April 2017
Symposium ED5 — Photoactive Nanoparticles and Nanostructures

Nanoscale Optical Interactions in Precise Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

We use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to direct molecules into desired positions to create nanostructures with controlled environments and dimensionality, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules and assemblies. We have developed and applied new multimodal nanoscale analysis tools based on the scanning tunneling microscope (STM) to measure structure, function, and spectra simultaneously. We are particularly interested in the interactions of photons with precisely assembled structures. The measured results of photoexcitation include photoconductivity and regioselective reaction. We apply this method to optimize molecules and materials for energy conversion and storage. Related imaging spectroscopies we have developed give access to the cooperative action of assembled molecular motors and the identification and orientations of parts of molecules such as amyloid-forming oligopeptides without averaging and without the need to crystallize the biomolecular assemblies. Concepts from sparsity and compressive sensing are developed and applied to guide efficient data acquisition and to accelerate data analysis and information assembly.


Friday 21 April 2017
Inaugural IEEE Nano Montreal Lecture, INRS-EMT, Montreal, Quebec, Canada

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Thursday 27 April 2017, 1030 AM
McGill University, Department of Physics, Condensed Matter Physics Seminar, Montreal, Quebec, Canada

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Tuesday 2 May 2017, 510 PM
International Symposium on Flexible and Stretchable Devices, Innovative Centre for Flexible Devices (iFlex) Opening Symposium, Nanyang Executive CentreNanyang Technological University, Singapore

Nanoscience Approaches to Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to sensing, imaging, and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include using biomolecular recognition in nanobiosensor arrays to probe dynamic chemistry in the brain and microbiome systems. It also includes fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Thursday 4 May 2017
School of Physical and Mathematical Sciences, Physics and Applied Physics Colloquium, Nanyang Technological University, Singapore

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The great promise of single-molecule/assembly measurements is to understand how critical variations in structure, conformation, and environment relate to and control function. New approaches to sensing, imaging, and analysis are keys to elucidating these associations. I will discuss current and upcoming advances and will pose the challenges that lie ahead in creating, developing, and applying new tools for biology and medicine. These advances include using biomolecular recognition in nanobiosensor arrays to probe dynamic chemistry in the brain and microbiome systems. It also includes fusing spectroscopic imaging modalities and freeing up bandwidth in measurements to record simultaneous data streams and to expand our dynamic range. Recent advances in sparsity and compressive sensing can be applied both to new analysis methods and to directing measurements so as to assemble and to converge structural and functional information. Early examples will be discussed.


Friday 5 May 2017, 3 PM
Indian Institute of Technology Institute Lecture, Indian Institute of Technology Madras, ICSR Auditorium, Chennai, India

Exploring the Ultimate Limits of Miniaturization and Global Opportunities in Nanoscience and Nanotechnology
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

Two seemingly conflicting trends in nanoscience and nanotechnology are our increasing ability to reach the limits of atomically precise structures and our growing understanding of the importance of heterogeneity in the structure and function of molecules and nanoscale assemblies. I will discuss the challenges, opportunities, and consequences of pursuing strategies to address these goals. In our laboratories, we use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to explore the ultimate limits of miniaturization. We direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood, and exploited at unprecedented scales. Such interactions can be used to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule/assembly measurements in order to develop sufficiently significant statistical distributions, while retaining the intrinsic heterogeneity in the measured function of the molecules and assemblies. We have likewise developed and applied the means to map buried chemical functionality and interactions. The next steps are to apply these ideas to biomolecular assemblies and larger biological systems to understand the variations in structure and function that have been inaccessible to study.


Wednesday 10 May 2017, 9 AM
Surface Canada 2017, Montreal, Quebec, Canada, Tuesday 9 - Friday 12 May 2017

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA and Institut National de la Recherche Scientifique (INRS) Centre for Energy, Materials and Telecommunications, Montreal, Quebec, Canada

We use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to explore the ultimate limits of miniaturization. We direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood, and exploited at unprecedented scales. Such interactions can be used to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. We selectively test hypothesized mechanisms of function by varying molecular design, chemical environment, and measurement conditions to enable or to disable function and control using predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule/assembly measurements in order to develop sufficiently significant statistical distributions, while retaining the heterogeneity intrinsic in the measurements. We use a number of excitation mechanisms to induce changes in the molecules and assemblies, including electric field, light, electrochemical potential, ion binding, and chemistry. We measure the electronic coupling of the contacts between the molecules and substrates by measuring the polarizabilities of the connected functional molecules. We have likewise developed and applied the means to map buried chemical functionality and interactions. The next steps are to learn to assemble and to operate molecules together, both cooperatively and hierarchically, in analogy to biological muscles. We discuss our initial efforts in this area, in which we find both interferences and cooperativity.


Monday 15 May 2017, 7 PM
INRS-EMT Public Lecture, Montreal, Quebec, Canada

Exploring the Ultimate Limits of Miniaturization and Global Opportunities in Nanoscience and Nanotechnology
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

Two seemingly conflicting trends in nanoscience and nanotechnology are our increasing ability to reach the limits of atomically precise structures and our growing understanding of the importance of heterogeneity in the structure and function of molecules and nanoscale assemblies. I will discuss the challenges, opportunities, and consequences of pursuing strategies to address these goals. In our laboratories, we are taking the first steps to exploit precise assembly to optimize properties such as perfect electronic contacts in materials. We are also developing the means to make tens to hundreds of thousands of independent multimodal nanoscale measurements in order to understand the variations in structure and function that have previously been inaccessible in both synthetic and biological systems.


Wednesday 24 May 2017, 6 PM, UCLA Faculty Center
American Chemical Society, Southern California Section, Richard C. Tolman Medal, Los Angeles, CA

Exploring the Ultimate Limits of Miniaturization
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

We use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to explore the ultimate limits of miniaturization. We direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood, and exploited at unprecedented scales. Such interactions can be used to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. We selectively test hypothesized mechanisms of function by varying molecular design, chemical environment, and measurement conditions to enable or to disable function and control using predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule/assembly measurements in order to develop sufficiently significant statistical distributions, while retaining the intrinsic heterogeneity in the measured function of the molecules and assemblies. We have likewise developed and applied the means to map buried chemical functionality and interactions. The next steps are to apply these ideas to biomolecular assemblies and larger biological systems to understand the variations in structure and function that have been inaccessible to study.


Thursday 1 June 2017, 12 PM, CNSI Auditorium
UCLA Department of Chemistry, Los Angeles, CA

Aptamer-Functionalized Field-Effect Transistors for Neurotransmitter Sensing
Nako Nakatsuka, Department of Chemistry & Biochemistry, UCLA, Los Angeles, CA 90095

The BRAIN Initiative aims to unite nanotechnology and neuroscience to investigate neural circuitry within the complex landscape of the brain at the spatiotemporal scales pertinent to information encoding. Investigating how malfunctioning neural networks, which underlie brain-related disorders, are associated with neurotransmitter flux necessitates chemically specific, in vivo neurotransmitter sensors. We propose coupling the molecular recognition properties of rationally designed, chemically synthesized DNA sequences, termed aptamers, with direct electronic detection via field-effect transistors. However, the discovery of neurotransmitter-specific aptamers has been impeded by conventional in vitro screening techniques. Thus, we developed "neurochips" having precise surface chemistries that enable high-affinity interactions between aptamers and target neurotransmitter molecules. Neurochips are able to capture and to sort aptamers targeting different neurotransmitters.

In parallel, we isolated high-affinity serotonin- and dopamine-specific aptamers via an alternative screening method. We then functionalized these aptamers onto the semiconducting channels of field-effect transistor arrays to monitor changes in neurotransmitter concentrations. We hypothesized that optimized binding-induced aptamer conformation changes will be transduced into electrical signals. Serotonin- and dopamine-specific devices showed high sensitivity with a detection limit of 10 fM. These devices retain their functionality in full ionic strength biological fluids including ex vivo brain tissue, suggesting a detection mechanism that corresponds to charge motion within Debye length limitations. We envision unprecedented capacity to measure neurochemical signaling directly, in vivo¸ and in real time, which will ultimately impact our understanding of brain function in relation to complex behaviors.


Friday 2 June 2017, 1035 AM
University of California, San Diego, Department of Nanoengineering, Tenth Anniversary Symposium, SME Building, UCSD, La Jolla, CA

Global Opportunities in Nanoscience and Nanotechnology
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

Two seemingly conflicting trends in nanoscience and nanotechnology are our increasing ability to reach the limits of atomically precise structures and our growing understanding of the importance of heterogeneity in the structure and function of molecules and nanoscale assemblies. I will discuss the challenges, opportunities, and consequences of pursuing strategies to address these goals. In our laboratories, we are taking the first steps to exploit precise assembly to optimize properties such as perfect electronic contacts in materials. We are also developing the means to make tens to hundreds of thousands of independent multimodal nanoscale measurements in order to understand the variations in structure and function that have previously been inaccessible in both synthetic and biological systems.


Saturday 3 June 2017, 8 PM, Gerald W. Lynch Theatre, John Jay College
World Science Festival

Much Ado about Nearly Nothing: Nanotech and the Future of Energy
Moderated by Walter Isaacson, Aspen Institute
Sanjoy Banerjee, CUNY Energy Institute
Yury Gogotsi, Drexel University
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

See a video of the event here


Sunday 4 June 2017, 11 AM, NYU Global Center, Grand Hall
World Science Festival

Nanotechnology's Promise: A Big Risk in a Small Package?
Moderated by Andrew Revkin, ProPublica.org
Vicki Colvin, Brown University
Ponisseril Somasundaran, Columbia University
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Monday 5 June 2017, 3 PM
J. E. Purkyne University, Departments of Chemistry and Physics, Faculty of Science, Fulbright Scholar Lecture, Prague, Czech Republic

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Tuesday 6 June 2017, 1 PM, Seminar Room S2.02, Purkynova 123, Brno

CEITEC and Fulbright Scholar Lecture, Brno, Czech Republic
Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Wednesday 7 June 2017, 10 AM, Narodni 3, Lecturing Hall 206
Joint Seminar of the Institute of Inorganic Chemistry and the of Institute of Physics, The Czech Academy of Sciences; Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Charles University; and Faculty of Science, Department of Physical Chemistry, Charles University, Fulbright Scholar Lecture, Prague, Czech Republic

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Thursday 8 June 2017, 10 AM
University of Chemistry and Technology, Department of Inorganic Chemistry, Faculty of Chemical Technology, Fulbright Scholar Lecture, Prague, Czech Republic

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Friday 9 June 2017, 10 AM University of Pardubice, Department of Physical Chemistry, Faculty of Science, Fulbright Scholar Lecture, Pardubice, Czech Republic

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Monday 12 June 2017, 130 PM
10th International Summer School on Physics at the Nanoscale, Institute of Physics, Czech Academy of Science, Devět Skal, Czech Republic, Monday 12 - Friday 16 June, 2017

Tutorial on Patterning across Scales
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Wednesday 14 June 2017, 950 AM
10th International Summer School on Physics at the Nanoscale, Czech Academy of Science, Devět Skal, Czech Republic, Monday 12 - Friday 16 June, 2017

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Thursday 15 June 2017, 830 PM
10th International Summer School on Physics at the Nanoscale, Czech Academy of Science, Devět Skal, Czech Republic, Monday 12 - Friday 16 June, 2017

Panel on Entrepreneurship
Christian Teichert, Austrian School of Mines
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095
Roland Wiesendanger, University of Hamburg, Hamburg, Germany


Tuesday 20 June 2017, 2 PM, CNSI Conference Rooms
UCLA Department of Materials Science & Engineering Thesis Defense

Fabricating Germanium Interfaces for Battery Applications
Andrew Serino, Department of Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Thursday 22 June 2017, 3 PM
International Conference on Chemical Bonding, Thursday 22 - Monday 26 June 2017

Imaging, Understanding, and Leveraging Buried Interactions in Supramolecular Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

Structural domains is self-assembled systems are well known. The types of domain boundaries can be simplified by using symmetric building blocks. Likewise, interactions can be designed into the building blocks to add stability to the systems. By developing new imaging tools that let us visualize these interaction networks, we have discovered that buried networks can cross structural domain boundaries, regions of disorder, and substrate step edges in monolayer systems.1-3 The interactions, their ranges and the consequences of these effects will be discussed.

1. Heads and Tails: Simultaneous Exposed and Buried Interface Imaging of Monolayers, P. Han, A. R. Kurland, A. N. Giordano, S. U. Nanayakkara, M. M. Blake, C. M. Pochas, and P. S. Weiss, ACS Nano 3, 3115 (2009).
2. Defect-Tolerant Aligned Dipoles within Two-Dimensional Plastic Lattices, J. C. Thomas, J. J. Schwartz, J. N. Hohman, S. A. Claridge, H. S. Auluck, A. C. Serino, A. M. Spokoyny, G. Tran, K. F. Kelly, C. A. Mirkin, J. Gilles, S. J. Osher, and P. S. Weiss, ACS Nano 9, 4734 (2015).
3. Mapping Buried Hydrogen-Bonding Networks, J. C. Thomas, D. P. Goronzy, K. Dragomiretskiy, D. Zosso, J. Gilles, S. J. Osher, A. L. Bertozzi, and P. S. Weiss, ACS Nano 10, 5446 (2016).


Thursday 29 June 2017, 410 PM. Ecole Polytechnique Montreal
IEEE N3 Summer School, Montreal, Canada, Wednesday 28 - Friday 30 June 2017

Cooperative Function in Atomically Precise Nanoscale Assemblies
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095, USA

We use molecular design, tailored syntheses, intermolecular interactions, and selective chemistry to explore the ultimate limits of miniaturization. We direct molecules into desired positions to create nanostructures, to connect functional molecules to the outside world, and to serve as test structures for measuring single or bundled molecules. Interactions within and between molecules can be designed, directed, measured, understood, and exploited at unprecedented scales. Such interactions can be used to form precise molecular assemblies, nanostructures, and patterns, and to control and to stabilize function. We selectively test hypothesized mechanisms of function by varying molecular design, chemical environment, and measurement conditions to enable or to disable function and control using predictive and testable means. Critical to understanding these variations has been developing the means to make tens to hundreds of thousands of independent single-molecule/assembly measurements in order to develop sufficiently significant statistical distributions, while retaining the heterogeneity intrinsic in the measurements. We use a number of excitation mechanisms to induce changes in the molecules and assemblies, including electric field, light, electrochemical potential, ion binding, and chemistry. We measure the electronic coupling of the contacts between the molecules and substrates by measuring the polarizabilities of the connected functional molecules. We have likewise developed and applied the means to map buried chemical functionality and interactions. The next steps are to learn to assemble and to operate molecules together, both cooperatively and hierarchically, in analogy to biological muscles. We discuss our initial efforts in this area, in which we find both interferences and cooperativity.


Tuesday 4 July 2017, 830 AM
10th ICNP - International Conference on Nanophotonics, Recife, Brazil, Sunday 2 - Wednesday 6 July 2017

Global Opportunities in Nanoscience and Nanotechnology
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

Two seemingly conflicting trends in nanoscience and nanotechnology are our increasing ability to reach the limits of atomically precise structures and our growing understanding of the importance of heterogeneity in the structure and function of molecules and nanoscale assemblies. By having developed the "eyes" to see, to record spectra, and to measure function at the nanoscale, we have been able to fabricate structures with precision as well as to understand the important and intrinsic heterogeneity of function found in these assemblies.

I will discuss the challenges, opportunities, and consequences of pursuing strategies to address both precision on the one hand and heterogeneity on the other [1]. In our laboratories, we are taking the first steps to exploit precise assembly to optimize properties such as perfect electronic contacts in materials [2]. We are also developing the means to make tens to hundreds of thousands of independent multimodal nanoscale measurements in order to understand the variations in structure and function that have previously been inaccessible in both synthetic and biological systems [3,4].

Another outcome of the development of our field has been our ability to communicate across fields [5,6]. This skill that we develop in our students and colleagues has enhanced and accelerated the impact of nanoscience and nanotechnology on other fields, such as neuroscience and the microbiome [7,8]. I will discuss the opportunities presented by these entanglements and give recent examples of advances enabled by nanoscience and nanotechnology [9,10].

References
[1] C. R. Kagan, L. E. Fernandez, Y. Gogotsi, P. T. Hammond, M. C. Hersam, A. E. Nel, R. M. Penner, C. G. Willson, and P. S. Weiss, ACS Nano 10, 9093-9103 (2016).
[2] P. Han, K. Akagi, F. F. Canova, R. Shimizu, H. Oguchi, S. Shiraki, P. S. Weiss, N. Asao, and T. Hitosugi, ACS Nano 9, 12035-12044 (2015).
[3] B. K. Pathem, S. A. Claridge, Y. B. Zheng, and P. S. Weiss, Annual Review of Physical Chemistry 64, 605-630 (2013).
[4] D. Yugay, D. P. Goronzy, L. M. Kawakami, S. A. Claridge, T.-B. Song, Z. Yan, Y.-H. Xie, J. Gilles, Y. Yang, and P. S. Weiss, Nano Letters 16, 6282-6289 (2016).
[5] W. W. C. Chan, M, Chhowalla, S. Glotzer, Y. Gogotsi, J. H. Hafner, P. T. Hammond, M. C. Hersam, A. Javey, C. R. Kagan, A. Khademhosseini, N. A. Kotov, S.-T. Lee, Y. Li, H. Möhwald, P. A. Mulvaney, A. E. Nel, P. J. Nordlander, W. J. Parak, R. M. Penner, A. L. Rogach, R. E. Schaak, M. M. Stevens, A. T. S. Wee, C. G. Willson, L. E. Fernandez, P. S. Weiss, ACS Nano 10, 10615-10617 (2016).
[6] J. A. Jackman, D.-J. Cho, J. Lee, J. M. Chen, F. Besenbacher, D. A. Bonnell, M. C. Hersam, P. S. Weiss, and N.-J. Cho, ACS Nano 10, 5595-5599 (2016).
[7] A. P. Alivisatos, A. M. Andrews, E. S. Boyden, M. Chun, G. M. Church, K. Deisseroth, J. P. Donoghue, S. E. Fraser, J. Lippincott-Schwartz, L. L. Looger, S. Masmanidis, P. L. McEuen, A. V. Nurmikko, H. Park, D. S. Peterka, C. Reid, M. L. Roukes, A. Scherer, M. Schnitzer, T. J. Sejnowski, K. L. Shepard, D. Tsao, G. Turrigiano, P. S. Weiss, C. Xu, R. Yuste, and X. Zhuang, ACS Nano 7, 1850-1866 (2013).
[8] J. S. Biteen, P. C. Blainey, Z. G. Cardon, M. Chun, G. M. Church, P. C. Dorrestein, S. E. Fraser, J. A. Gilbert, J. K. Jansson, R. Knight, J. F. Miller, A. Ozcan, K. A. Prather, S. R. Quake, E. G. Ruby, P. A. Silver, S. Taha, G. van den Engh, P. S. Weiss, G. C. L. Wong, A. T. Wright, and T. D. Young, ACS Nano 10, 6-37 (2016).
[9] J. Kim, Y. S. Rim, H. Chen, H. H. Cao, N. Nakatsuka, H. L. Hinton, C. Zhao, A. M. Andrews, Y. Yang, and P. S. Weiss, ACS Nano 9, 4572-4582 (2015).
[10] M. Ding, H.-Y. Shiu, S.-L. Li, C. K. Lee, G. Wang, H. Wu, N. O. Weiss, T. D. Young, P. S. Weiss, G. C. L. Wong, K. H. Nealson, Y. Huang, and X. Duan, ACS Nano 10, 9919-9926 (2016).


Wednesday 12 July 2017, 6 PM, Café Artscience: Honeycomb, Cambridge, MA
Cafe Art|Science, Cambridge, MA

A Discussion on the NAKFI Process
Brandon Ballengee,
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095
Moderated by JD Talasek, Cultural Programs of the National Academy of Sciences, Washington, DC


Friday 21 July 2017, 930 AM
Micro- and Nanotechnologies for Medicine: Emerging Frontiers and Applications, Cambridge, Massachusetts, Monday 17 - Friday 21 July 2017

Addressing Heterogeneity in Biological Systems
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Wednesday 26 July 2017, 1145 AM
Chemeca and Centenary of the Royal Australian Chemical Institute, Melbourne, Australia, Monday 24 - Wednesday 26 July 2017

Precise Chemical, Physical, and Electronic Nanoscale Contacts
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

The physical, electronic, mechanical, and chemical connections that materials make to one another and to the outside world are critical. Just as the properties and applications of conventional semiconductor devices depend on these contacts, so do nanomaterials, many nanoscale measurements, and devices of the future. We discuss the important roles that these contacts can play in preserving key transport and other properties. Initial nanoscale connections and measurements guide the path to future opportunities and challenges ahead. Band alignment and minimally disruptive connections are both targets and can be characterized in both experiment and theory. I discuss our initial forays into this area in a number of materials systems.


Wednesday 26 July 2017, 130 PM
Academic Sharp Brain Competition (Judge) at Chemeca and Centenary of the Royal Australian Chemical Institute, Melbourne, Australia, Monday 24 - Friday 28 July 2017

Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095


Thursday 27 July 2017
RMIT University, Melbourne, Australia

Global Opportunities in Nanoscience and Nanotechnology
Paul S. Weiss, California NanoSystems Institute and Departments of Chemistry & Biochemistry and Materials Science & Engineering, UCLA, Los Angeles, CA 90095

Two seemingly conflicting trends in nanoscience and nanotechnology are our increasing ability to reach the limits of atomically precise structures and our growing understanding of the importance of heterogeneity in the structure and function of molecules and nanoscale assemblies. By having developed the "eyes" to see, to record spectra, and to measure function at the nanoscale, we have been able to fabricate structures with precision as well as to understand the important and intrinsic heterogeneity of function found in these assemblies.

I will discuss the challenges, opportunities, and consequences of pursuing strategies to address both precision on the one hand and heterogeneity on the other. In our laboratories, we are taking the first steps to exploit precise assembly to optimize properties such as perfect electronic contacts in materials. We are also developing the means to make tens to hundreds of thousands of independent multimodal nanoscale measurements in order to understand the variations in structure and function that have previously been inaccessible in both synthetic and biological systems.

Another outcome of the development of our field has been our ability to communicate across fields. This skill that we develop in our students and colleagues has enhanced and accelerated the impact of nanoscience and nanotechnology on other fields, such as neuroscience and the microbiome. I will discuss the opportunities presented by these entanglements and give recent examples of advances enabled by nanoscience and nanotechnology.



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30 July 2017

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