Photoacoustic calorimetry is a relatively new technique presently used to study organic photochemical reactions but not yet fully applied to biological problems. It has the potential capability of monitoring in real time the volume change of a protein following a fast perturbation. It measures nonradiative heat release in molecules after absorption of a photon, thus measuring energy depositions ignored by luminescence experiments. Dr. Rudzki plans to show that pulsed-laser, time-resolved photoacoustic calorimetry can be used to detect volume changes and surface charge changes in proteins resulting from conformational transitions. The enthalpic, intrinsic volume and surface charge changes in carboxymyoglobin following absorption of a photon will be studied. The long term goal is to better understand protein dynamics, in particular, changes in protein conformation in response to stimuli.
