Our research is focused on the use of single molecule techniques to understand molecular dynamic processes and the effects of the local environment on these processes. We have been developing and applying time-resolved, nanoscale site-specific, single molecule methods that are an effective alternative to conventional methods, providing information under conditions most applicable to the natural processes underlying the area of research interest. Single-molecule approaches are useful and unique in studying heterogeneous and complex systems because the inhomogeneity can be identified and/or removed by studying one molecule at a time. Single molecules and molecular complexes can be observed as they traverse a wide range of energy states in real-time and the effect of this ever changing "system configuration" on chemical/biological reactions and other dynamical processes can be mapped.
Our current research work has been focused on (1) conformational dynamics and reaction in proteins and protein complexes under physiological conditions, and our long-term goal is to study single-molecule protein conformational dynamics and reactions in living cells; and (2) inhomogeneous interfacial chemical and biological reaction dynamics in solar energy conversion, bioremediation, and environmental systems, focusing on fundamental understanding of the controlling physical and chemical properties, such as, Franck-Condon coupling and barrier, vibrational and solvent relaxation energetics, molecular distributions, redox states identification, and molecular motions.