Spectrophotometric assay of formylmethylflavin and photoproduct-lumichrome in organic solvents.

A spectrophotometric method has been developed for the assay of formylmethylflavin and its major photoproduct, lumichrome, in organic solvents. Absorption measurements are made at the respective maxima of the two compounds and the concentrations are determined by a two-component assay. The reproducibility of the method lies within +/- 5 percent. The method is specific and can be conveniently employed for photodegradation studies of formylmethylfavin in organic solvents.