A chromatographic method for the detection of tryptophan metabolites.

During the course of investigations involving the action of tissue slices on tryptophan, the aqueous medium in which n-kynurenine sulfate had been incubated with kidney slices was found to have acquired a marked bluish violet fluorescence. Subsequent investigation showed that several known metabolites of tryptophan fluoresce when suitably exposed to ultraviolet light. Advantage has been taken of this behavior and of separation by paper chromatography to identify a number of the products formed when tryptophan and certain of its metabolites are incubated with slices of rat liver or rat kidney. This communication describes our observations.