Ph.D. Bowling Green State University 1993; M.S. University of Rochester 1989; B.S. State University of New York at Geneseo 1988
Photochemical probes of macromolecular structure.
Advances in genomics and proteomics require new tools in molecular biology. In our laboratory, we are developing synthetic organic and inorganic molecules as structural probes of DNA and proteins. Through molecular engineering, we synthesize the compounds to recognize and bind to specific DNA sequences or protein residues. To date, we have used naphthalimide derivatives that are readily synthesized and functionalized. Upon activation with UV or visible light, the compounds initiate a sequence of chemical events that lead to cleavage of the macromolecule at the binding site. In parallel, transient laser spectroscopy is used to understand reaction mechanisms. Once the fragments are identified using HPLC and mass spectrometry, the DNA or protein structure may be reconstructed. Thus, these 'photonucleases' and 'photoproteases' provide new tools to identify the sequence and 3D structure of DNA and proteins.
Stimuli-responsive polymers find broad-ranging applications in smart materials and smart packaging applications. Our group is interested in building functionalized polymers that respond, via basic photophysical phenomena, to changes in external stimuli (temperature, pressure, etc.). Fundamentally, we are interested in gaining knowledge about how the polymer architecture governs, among other things, the thermal properties of the polymer. Traditional synthetic polymer chemistry is used to systematically build and functionalize the polymers. NMR, mass spectrometry, and DSC are used to characterize the materials. Steady-state and time-resolved fluorescence methods are used to understand the fundamental photophysics. Specifically, using time-correlated single-photon counting, the polymer dynamics and rate constants for excited-state interconversions, are mapped out to understand which elementary reaction step controls the temperature-dependent photophysics. As a result, systematic structure-function correlations are obtained.