CINT Announces First Post-Docs

Steve Koch received a B.S. degree (Physics, 1996) from the University of Michigan in Ann Arbor and M.S. and Ph.D. degrees (Physics major, Biophysics minor, 2003) from Cornell University in Ithaca, NY. Steve's undergraduate work included assisting in a genetics research laboratory at U of M (Francis Collins) and working on infrared non-destructive evaluation technology at Argonne National Lab (Bill Ellingson). After a brief stint in superfluid helium research (Jeevak Parpia), Steve completed his graduate work in biophysics (Michelle Wang) where he worked on a team that developed optical tweezers methods to study single biomolecules. This work led to a patent application for a new single-molecule technique for studying protein-DNA interactions.

As a CINT Postdoctoral Fellow, Steve has formed a collaborative team between Los Alamos and Sandia National Laboratories scientists to establish for CINT state of the art capabilities in single molecule (SM) force measurements. The LANL team members (Jim Werner, Peter Goodwin, Lawrence Pratt, Dick Keller) and Sandia team members (Steve, Gayle Thayer, Jim Martin, George Bachand, Bruce Bunker) contribute strengths in single-molecule detection and manipulation, electromagnetics, surface science, molecular biology, computer automation, and theoretical modeling and simulation. These strengths are being leveraged to construct a novel instrument that will apply computer-controlled electromagnetic forces to hundreds of SMs in parallel and rapidly obtain SM force information. One of the first applications of the instrument will be to study the effects of water on protein-DNA interactions by literally unzipping single molecules of DNA in the presence of proteins. While he expects very interesting results from the initial experiments, Steve also believes the technology will be an exciting single-molecule tool for external CINT users in addition to supporting existing Sandia and LANL missions.

Nanguo Liu was born and raised in Yangquan, a beautiful, remote, mountainous countryside in the northwest of the Hunan Province, China. In 1992, he enrolled in the Chemistry and Molecular Engineering Department of Peking University. After graduating with a BS degree in chemistry in 1997, Liu began studying for an MS degree in polymer science and engineering at the Changchun Institute of Applied Chemistry (CIAC), Chinese Academy of Sciences. In 1999 he left the CIAC to pursue studies at the University of New Mexico, where in May 2004 he was awarded a Ph.D. in engineering under the direction of Professor C. Jeffrey Brinker for his work on nanoporous and nanocomposite silica materials. Dr. Liu is a co-author of ten research articles in this area, and he continues to work as a postdoctoral fellow with Professor Brinker on functional, mesoporous, membrane-based synthetic ion channels for DNA sequencing and molecular recognition. In 2004 he was awarded a CINT Postdoctoral Fellowship, and he plans to begin working in the area of nanoscience (as it pertains to colloidal nanocrystals and nanocrystal assemblies) at Los Alamos National Laboratory in October 2004.

As a CINT Postdoctoral Fellow Nanguo will do his research work at Los Alamos in the Softmatter Nanotechnology and Advanced Spectroscopy Group. As a Colloidal nanocrystal quantum dots (NQDs) are of interest for their size-tunable optical and electronic properties as well as their unique photophysical characteristics. Although tremendous strides have been made in nanoscience as it relates to NQDs, many challenges still exist. For example, in order to realize optical applications of NQDs, stabilization of these materials in a processible medium is required. Dr. Liu’s research will focus on the development of synthetic pathways for encapsulating NQDs into various host matrices, such as sol-gel, while still preserving their unique electronic and optical properties. The resulting nanocomposites are expected to have high NQD volume loadings and excellent mechanical and photochemical stabilities, which should facilitate their use in technologies such as optical amplification and lasing. In addition, these types of materials will be combined with photonic structures to enhance NQD optical gain performance, thereby improving the technological potential for NQDs as lasing materials.

While initial studies will focus on samples of randomly distributed NQDs in inorganic oxides, Dr. Liu will also concentrate on fabricating composite materials featuring organized, three-dimensional arrays of NQDs. One approach to this task involves extending work initiated by C. J. Brinker at Sandia National Laboratories on the preparation of ordered, three-dimensional gold nanocrystal/silica arrays to new systems of NQDs. In this case, selection of the building blocks will be dictated by the applications of interest. Once prepared, the NQD-matrix materials can be integrated into devices and characterized utilizing capabilities unique to Los Alamos and Sandia, including the Advanced Materials Laboratory and the Center for High Technology Materials.