California NanoSystems Institute
CNSI
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November 25, 2008

Maxime Dahan
Physics & Biology Department
Ecole Normale Superior (Paris)


Streaming Video
  

When nanomaterials meet biology: watching cellular processes one quantum dot at a time
Nanomaterials hold great promise for ultrasensitive biological detection. Semiconductor quantum dots (QDs) are probably the most prominent example of functionalized nanoparticles used in cell biology. In the past years, QDs have been increasingly used as fluorescent probes for single-molecule experiments in live cells. I will show how single QD imaging can be readily used for deciphering complex biological processes and addressing the principles underlying cellular organization and dynamics. The talk will be illustrated by the results of experiments on the membrane dynamics of post-synaptic receptors, the chemotactic guidance of nerve cells or the transport properties of molecular motors. I will finally discuss the challenges in terms of physical chemistry, biochemical functionalization and optical imaging that need to be addressed to make single QD tracking a standard tool in cell biology.

November 18, 2008

Harm-Anton Klok
Department of Materials Science and Engineering
Ecole Polytechnique Fédérale de Lausanne (EPFL)


Streaming Video
  

Biohybrid nanomedicines and self-assembling biomaterials
Coiled coils are superhelical assemblies of two or more helical peptides that are wrapped around each other in a superhelical fashion. The coiled coil motif is ubiquitous in biology and found in more than 200 native proteins. Coiled coils are found both in structural proteins (e.g. keratin) but also play a key role in e.g. DNA transcription and viral fusion processes.

This presentation will discuss the use of coiled coil peptide sequences for the preparation of novel biohybrid nanomedicines and self-assembling materials.

The first part of the presentation will focus on the synthesis and characterization of a family of poly(ethylene glycol) (PEG) ? coiled coil peptide conjugates that are designed to competitively inhibit or disrupt coiled coil oligomerization processes that are related to human disease. As a first proof of concept, PEG ? coiled coil conjugates were prepared that were designed to target the coiled coil domains of the transcription factor AP-1, which plays a significant role in breast cancer, and the Ebola virus glycoprotein 2 (GP2). Target hybridization of the PEG-peptide conjugates was confirmed in model experiments using circular dichroism spectroscopy and 15N HSQC NMR techniques.

The second part of the presentation will discuss a short, heterodimeric coiled coil motif that is characterized by a very high stability under physiological conditions, but which unfolds upon a change in pH from 7 to 5. This pH range is attractive as it may allow for intracellular release, taking advantage of the drop in pH that accompanies cellular uptake via the endosomal pathway. After a presentation of the folding properties of this heterodimeric coiled coil motif, opportunities for the construction of non-covalent polymer therapeutics and micellar nanocarriers will be discussed.


November 04, 2008

Manfred Wuttig
Department of Materials Science and Engineering
University of Maryland
Solution Processed Multiferroic Nanostructures through Block Copolymer Self-Assembly
A magnetoelectric (ME) composite with controlled nanostructures is synthesized using co-assembly of two inorganic precursors with a block copolymer. This solution processed material consists of hexagonally arranged ferromagnetic cobalt ferrite [CoFe2O4, CFO] nano- cylinders within a matrix of ferroelectric lead zirconium titanate [Pb1.1(Zr0.53Ti0.47)O3, PZT] when thin films were prepared by spin coating. The initial magnetic permeability of the self-assembled CFO/PZT nano-composite changes by a fac-tor of five through the application of 2.5 V. This work also demonstrates for the first time that a block copolymer can be used to simultaneously template two inorganic phases to form a nanoscale composite.

October 21, 2008

Scott Sills
Advanced Technology Group, Micron Technology, Inc.


Streaming Video
  

No Moore: Will nanotechnology trump Moore's law?
Since Gordon Moore reported on the growth rate for microchip transistor densities in 1965, sustaining this trend has become the manifest destiny of the semiconductor industry. Success and the perpetuation of Moore's trend, as a Law, have continued through decades of top-down scaling of the photolithographic patterning process. While state-of-the-art 193nm immersion lithography is printing 40nm features and extreme ultraviolet (EUV) offers a prospective 22nm node, uncertainties for the future of optical lithography combined with advances in nanotechnology have opened a window of opportunity for emerging alternatives. Revolutionary bottom-up techniques that employ molecular self-assembly and bio-recognition hold promise for sub-lithographic patterning; however, culturing viable technologies from these sciences requires more than enhanced resolution. In this talk, we'll explore the critical parameter space that shapes the landscape between nanoscience and nanotechnology. We'll consider previous experiences where new technologies boasting superior resolution have challenged conventional photolithography and failed. With these lessons, we will work to outline the criteria for developing successful nanopatterning technologies and to elucidate the technological interface where bottom-up meets top-down. It is at this interface, where the fate of Moore's law ultimately lies.

October 14, 2008

Steve Koonin
Chief Scientist, British Petroleum
Energy Technologies that could make a difference
The world's demand for energy will grow by some 40% in the next 20 years. Satisfying that demand in an economical and environmentally acceptable manner is one of the most significant challenges facing society. New technologies will play a central role in meeting this challenge, albeit conditioned by the economic, social, and political contexts in which they are developed and deployed. The presentation will focus on the major forces shaping the World's energy future and the technologies required to respond to them.
October 07, 2008

Eiichi Nakamura
Department of Chemistry
University of Tokyo


Streaming Video
  

Imaging of Single Organic Molecules in Motion
Imaging of single organic molecules has been made possible with the aid of high-resolution transmission electron microscope. The most attractive feature of this new methodology is its ability to allow us to capture motion pictures of single molecules undergoing structural change and translation. The first images were reported in 2007 for alkylcarboranes confined in a carbon nanotube, and the most recent images have provide information on the conformational change of more structurally complex polyamide molecules covalently attached to the outer surface of a carbon nanotube.