Time resolved fluorimetry and phosphorimetry are being developed and used for selective trace analysis of drugs. The time resolved phosphorimeter consists of a conventional low pressure N2-laser-sample cell (77-298 K)- photodetector-signal averager-digital computer; the time resolved fluorimeter consists of an atmospheric pressure N2 laser newly designed dye laser-sample cell (77-298 K)-photodetector-Hamamatsu streak camera-digital computer. The former device resolves species with lifetimes longer than approximately 10 microseconds and the latter device resolves species with lifetimes less than approximately 0.1 microseconds and larger than approximately 100 picoseconds. Single vs multiple photon excitation (use of a Chromatix CMX-4, a N2-dye laser, and a Coherent CW Ar ion-dye laser) of drugs in the condensed phase with luminescence and photoacoustic detection are being developed as selective, sensitive, precise methods of fingerprinting and quantitating drugs in extracts of biological fluids, of pharmaceutical preparations, and of other biological preparations and in separated (partially) liquid chromatographic effluents. Analytical figures of merit including limits of detection, linear dynamic ranges, sensitivities, precisions and selectivities will be determined for a number of drugs by the various spectroscopic methodologies. Finally, room temperature phosphorimetry is being refined with respect to substrate (including new materials like semiconductive materials) environment, and potential clinical applications. Other studies in progress include: the Shpolski effect to increase resolution of drugs, x-ray excited luminescence, mercury excited energy transfer to organic species, luminescence and photoacoustic detection of species in gas and liquid chromatography, and multiple photon excitation techniques to increase sensitivity and selectivity of analysis.
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