Specific determination of histamine in fish by high-performance liquid chromatography after diazo coupling

A new approach to the pre-column derivatization and analysis of histamine by HPLC is described, the method being based upon the formation of a diazo-coupled derivative of histamine. This derivatization method is simple, efficient, sensitive and specific for histamine and other imidazole compounds without a preliminary clean-up step. The liquid chromatographic system allows for rapid, bonded-phase separation with visible-light detection of these compounds within 20 min at a 10-pmol sensitivity. By using this method, the production of a large amount of histamine was confirmed in the muscle of mackerel Scomber japonicus incubated with the intestinal contents of the mackerel.