Under the Shared Instrumentation Grant program, we request a PRA (Photochemical Research Associates, Inc.) Fluorescence Lifetime Apparatus with the additional capability to determine phosphorescence lifetimes. As discussed in the proposal, three NIH-supported user groups have been identified at CWRU for which such instrumentation would make a major contribution to work in progress. Although these programs currently make use of steady state measures of fluorescence intensity, quenching by intrinsic and extrinsic agents, polarization, and solvent effects, none of these methods--in the absence of extensive lifetime measurements--allow molecular level dynamic properties of the systems to be defined in the detail required. The PI's of the three initial user groups will constitute the operations committee with KAK as its chairman. Matters of time allocation and operation policy will be determined by this committee. The Instrument will be housed in the Surgery Department's Optical Spectroscopy Laboratory which is housed in the Research Building at Cleveland Metropolitan General Hospital.
