Electrochemical detection of biogenic amines following acylation by N-hydroxysuccinimide esters

A general methodology for the selective derivatization of amines, to enable quantitation by high pressure liquid chromatography with electrochemical detection, is presented. N-Hydroxysuccinimide active esters present in large excess are suitably mild acylating agents to derivatize selectively trace quantities of amines for electrochemical detection. The 2 separate problems of extraction yield and detectability can be solved by this derivatization method. Due to its lipophilicity the resulting N-acylated amine, as demonstrated with serotonin, is extracted efficiently into organic solvents during sample preparation for chromatography. Moreover, the acyl group introduced can be designed to be electroactive, thus extending the procedure to amines not readily oxidized, e.g., histamine and phenylethylamine.