PULSED LASER INDUCED SIMULTANEOUS FLUORESCENCE AND PHOTOACOUSTIC SPECTROSCOPIC STUDIES OF FLAVIN ADENINE DINUCLEOTIDE (FAD) IN WATER

摘要

Flavin-adenine dinucleotide (FAD) is an important coenzyme of various flavoproteins in our body. It displays highly heterogeneous fluorescence intensity decay in solution. In the present study, we have recorded the fluorescence and photoacoustic spectra at different concentrations of FAD simultaneously, showing how the radiative and non-radiative relaxation pathways differ as a function of concentration The energy lost in the fluorescence path of FAD, due to different quenching phenomena like self quenching, resonance energy transfer (RET), solvation relaxation etc is clearly seen from the photoacoustic signal intensity which increases as the fluorescence intensity decreases.