Thin-layer chromatography of histidine, histamine and histidyl peptides at picomole level using a unique fluorogenic reaction with fluorescamine.

A thin-layer chromatography procedure has been devised for detecting histidine, histamine, histidyl peptides and related imidazole compounds; it is based on a unique fluorogenic reaction, in which the compounds are derivatized with fluorescamine, converted into different fluorescent products by heating in strong acid medium, and separated on silica gel plates with an appropriate solvent system. As little as 4 to 60 pmole of the histidine derivative could be detected under long-wave (366 nm) ultraviolet radiation. Other classes of compounds gave no fluorescent spots.