Plenary Speaker

Eric W. Kaler

Departments of Materials Science and Chemistry
Stony Brook University
Stony Brook, NY 11794

Micellar Networks - Implications for Rheology and Biology

Abstract: Many nonionic surfactants form micellar networks in water over a range of compositions and conditions, and theory suggests that the presence and nature of these networks is closely related to the presence of miscibility gaps in the phase diagram. The micelles can be directly observed by cryogenic transmission electron microscopy (cryo-TEM) and quantified by small-angle neutron scattering measurements. Convenient experimental systems with which to explore the features of such networks include alkyl monoglucosides surfactants and various additives. The temperature dependence of the phase separation observed in the binary glucoside -water mixture is explained in terms of the average curvature of the surfactant aggregate, and on the thermodynamic trade-off of micellar endcaps and junctions. As the phase boundary is approached, junctions become energetically more favorable than end-caps, and eventually the network becomes saturated. The miscibility gap can be eliminated either by the addition of an ethoxylated alcohol surfactant under conditions that promote the formation of micellar end caps, or by addition of an ionic surfactant that limits the formation of junctions. These changes in morphology have significant impacts on the flow properties of the solutions, and can create structures of potential use in the crystallization of membrane proteins.
Biosketch: Eric W. Kaler earned a B.S. degree in Chemical Engineering (with honors) from the California Institute of Technology in 1978 and a Ph.D. in Chemical Engineering from the University of Minnesota in 1982 working with L.E. Scriven and H.T. Davis. Dr. Kaler joined the faculty of the Department of Chemical Engineering at the University of Washington in 1982 and was promoted to Associate Professor in 1987. He moved to the Department of Chemical Engineering at the University of Delaware in 1989, became a Professor there in 1991, Department Chairman in 1996, and was appointed the Elizabeth Inez Kelley Professor of Chemical Engineering in 1998. He became Dean of the College of Engineering in 2000. In 2007 he became the Provost and Senior Vice President for Academic Affairs at Stony Brook University. His research interests are in the area of surfactant and colloid science, statistical mechanics, and thermodynamics.
     Dr. Kaler received one of the first Presidential Young Investigator Awards from the National Science Foundation in 1984, the Curtis W. McGraw Research Award from the American Society of Engineering Education in 1995, the 1998 American Chemical Society Award in Colloid or Surface Chemistry, and the 1998 ACS Delaware Section Award. He was elected a fellow of the American Association for the Advancement of Science in 2001 and received the Chilton Award from the Wilmington AIChE Section in 2002. In 2005, Dr. Kaler was awarded the E. Arthur Trabant Institutional Award for Women's Equity by the University of Delaware and received the Lectureship Award from the Division of Colloid and Surface Chemistry of the Chemical Society of Japan. He received the Kash Mittal Award from the Surfactants in Solution Symposium in 2006. He has chaired three Gordon Research Conferences and serves or has served on the editorial boards of the journals Langmuir, Colloids and Surfaces, Journal of Colloid and Interface Science, and AICHE Journal, and was an associate editor of the European Physical Journal. He is also the founding co-editor-in-chief of the journal Current Opinions in Colloid and Interface Science. He has been a consultant to numerous companies, has authored or co-authored over 200 peer-reviewed papers and holds ten U.S. patents.

Plenary Speaker

David A. Weitz

School of Engineering & Applied Sciences
Department of Physics
Harvard University
Cambridge, MA 02138

Structuring new colloidal materials with microfluidics

Abstract: This talk will describe how the precision control of fluid mixing afforded by microfluidic devices can be used to make new structures that allow colloidal and interfacial phenomena to be studied in exquisite detail and that enable fabrication of structures that facilitate encapsulation and controlled delivery of a wide range of substances.
Biosketch: Weitz received a PhD in Physics from Harvard University, and worked at Exxon Research and Engineering Co. He then became a Professor of Physics and the University of Pennsylvania, and moved to Harvard University about 9 years ago. He is currently a Professor of Physics and Applied Physics with appointments in both the Physics Department and the School of Engineering and Applied Sciences. He is also currently the director of the Harvard Materials Research Science and Engineering Center.

Winner - The Unilever Award

David S. Ginger

Department of Chemistry
University of Washington
Box 351700
Seattle, WA 98195-1700

Semiconductor Colloids and Scanning Probes for Organic LEDs and Solar Cells

Abstract: This talk will describe our work on the surface chemistry of colloidal semiconductor nanocrystal quantum dots as well as our application of new scanning probe microscopy techniques to the study of interfaces in thin-film polymer solar cells. First, we have fabricated efficient monochromatic light-emitting diodes using CdSe quantum dots as emissive layers. Optimizing particles for these applications requires better understanding and control over colloidal surface chemistry and optical properties. Monitoring the photoluminescence of a CdSe nanocrystal solution during the addition of a surfactant yields an intensity versus concentration curve that looks very similar to a classic Langmuir adsorption isotherm. However, we show that in order to interpret the data from such these experiments one must account for the extremely large number of surface binding sites on the nanocrystals. Furthermore, we use single particle spectroscopy to show that the ensemble photoluminescence is not simply proportional to the fraction of bound ligand sites on the nanocrystal surfaces. Finally, we address issues of polymer mixing and donor/acceptor interfaces that play critical roles in emerging thin-film LEDs and solar cells. We will describe the application of several scanning probe microscopy tools to probe charge generation, transport, and recombination in these heterogeneous mixtures of organic semiconductors.
Biosketch: David S. Ginger earned dual B.S. degrees in chemistry and physics at Indiana University in 1997 with honors and highest distinction. He received a British Marshall Scholarship and an NSF Graduate Fellowship and completed his Ph.D. in physics with Neil Greenham in the Optoelectronics group at the University of Cambridge (UK) in 2001. After a joint NIH and DuPont Postdoctoral Fellowship in Chad Mirkin's lab at Northwestern University, he joined the faculty at the University of Washington in Seattle where he is currently an Assistant Professor of Chemistry and an Adjunct Assistant Professor of Physics. He is a Research Corporation Cottrell Scholar, an Alfred P. Sloan Foundation Research Fellow, a Camille Dreyfus Teacher-Scholar, and a winner of the Presidential Early Career Award for Scientists and Engineers (from the AFOSR). He received the UW Chemistry Department Outstanding Teaching Award in 2007. His research centers on the physical chemistry of nanostructured materials with applications in optoelectronics and sensing.

Winner - Victor K. LaMer Award

Ali Khademhosseini

Harvard-MIT Division of Health Sciences and Technology
Massachusetts Institute of Technology
Cambridge, MA 02139

Department of Medicine
Brigham and Women's Hospital
Harvard Medical School
Boston, MA 02115

Microengineering the Cellular Environment for Tissue Engineering and Drug Discovery

Abstract: Micro- and nanoscale technologies are emerging as powerful tools to control the interaction between cells and their surroundings for biological studies, tissue engineering, diagnostics and cell-based screening. In our lab we have developed various approaches at the interface between materials science, engineering and biology to control and study the cellular microenvironment with emphasis on controlling stem cell differentiation and generating 3D tissues. In this talk I will present our work in controlling the cell-microenvironment interactions in 2D and 3D. To control cell migration and to restrict cell or colony size, cells and proteins were patterned using numerous methods based on micropatterning of polymers and by using stencils. To control cell-cell contact, we have developed methods based on layer-by-layer deposition of ionic biopolymers or surface topography to generate patterned co-cultures. In addition, we have developed methods of generating tissue-like structures with biomimetic microvasculature and complexity by using microengineered cell-laden hydrogels with controllable biochemical and architectural features.
Biosketch: Ali Khademhosseini is an Assistant Professor of Medicine and Health Sciences and Technology at Harvard-MIT's Division of Health Sciences and Technology and the Harvard Medical School. His research is based on developing micro- and nanoscale technologies to control cellular behavior with particular emphasis in developing surfaces, biomaterials and engineering systems for tissue engineering and drug delivery.

He has published 1 edited book, over 60 peer reviewed papers, 80 abstracts, 19 book chapters, and 14 issued or pending patents. He has received multiple awards including outstanding Undergraduate Research (UROP) mentor at MIT (2004), outstanding graduate student research by BMES (2005), outstanding research in polymer science by OMNOVA / MIT (2005) and the Coulter Foundation Early Career Award (2006). In 2007, he was recognized as one of the top young innovators (TR35) by the Technology Review Magazine. Also he won the BMW Scientific Award (2007), one of the most prestigious international young innovator awards. He received his Ph.D. (2005) in bioengineering from MIT under the supervision of Prof. Robert Langer, and MASc (2001) and BSc (1999) in chemical and biomedical engineering from University of Toronto.