Temperature and solvent effects on photoluminescence of tryptophan solutions

Abstract The fluorescence of tryptophan solutions in glycerol, water and ethanol was measured as a function of temperature using steady state and time-resolved techniques. The non-radiative rate constants responsible for the variation of fluorescence quantum yields with temperature are evaluated. Spectral shifts occurring on the nanosecond scale are interpreted in terms of an inversion of 1 L b and 1 L a states produced by solvent perturbation.