DETERMINATION OF THE pk VALUES OF THE LUMIFLAVIN TRIPLET STATE BY FLASH PHOTOLYSIS

Abstract

Abstract— The triplet‐triplet absorption spectra in aqueous solution of the acid ( 3 LfH 2 + ), the neutral ( 3 LfH) and the basic ( 3 Lf ‐ ) forms of lumifiavin (6,7,9‐trimethylisoalloxazine) were measured by flash photolysis. The p K a values of the corresponding protolytic equilibria of the lumifiavin triplet were found to be 4.4 5 ±0.1 and 9.8±0.15.