A new method for preparing flavin-adenine dinucleotide

Abstract

Chromatography on powdered cellulose was used to prepare flavinadenine dinucleotide (FAD) of 90% purity, free from contamination by other flavins and from contamination by compounds which absorb light between 240 and 510 m[mu]. The molecular extinction coefficients of FAD were reinvestigated. The possibility is discussed that the diminution in the absorption of FAD, at pH 7.0, relative to the combined absorption of its components (flavin mononucleotide and adenosine-5[image]-phosphate), is analogous to the quenching of fluorescence of FAD under similar conditions and is due to the formation of an internal complex.