Physical Chemistry Research

Investigation of Fluorescence Resonance Energy Transfer Relative to Macromolecular Geometry

Fluorescence resonance energy transfer (FRET) is the phenomenon by which energy is transferred from a donor molecule in the excited state to an acceptor molecule in the ground state.  This energy transfer occurs without the emission of a photon, but rather involves the long range dipole-dipole interactions between donor and acceptor.  If the distance between donor and acceptor remains constant over the excited state lifetime, energy transfer clearly demonstrates that this distance is less than the critical distance for transfer, which depends on the donor and acceptor characteristics.
This research will investigate FRET by finding suitable donor-acceptor pairs and placing them on opposite ends of medium-length polymer chains.  The amount of energy transfer will be determined and this will be related to the average distance between the two ends of the polymer chain. 
FRET has applications in medical diagnostics, DNA analysis, and optical imaging.  Specifically, it is ideal for determining protein size, membrane thickness, and determining distances between distinct sites on macromolecules.  The goal of this research will be to synthesize a molecule that clearly demonstrates this effect and to use the results to gain information about the dynamics of polymer chains in solution.