Use of 2,6-dinitro-4-trifluoromethylbenzenesulfonic acid as a novel derivatizing reagent for the analysis of catecholamines, histamines and related amines by gas chromatography with electron-capture detection.

We have found that 2,6-dinitro-4-trifluoromethylbenzenesulfonic acid reacts rapidly and specifically with primary amines at room temperature. We have used this reagent for derivatizing phenylethylamines, including catecholamines, and histamine and 1-methylhistamine. After the reaction, hydroxyl groups were derivatized to form the corresponding trimethylsilyl ethers, and the final derivatives were analyzed by gas chromatography with electron-capture detection. These derivatives are stable, possess excellent gas chromatographic properties and are detected with high sensitivity. We have applied this method to the analysis of histamine and 1-methylhistamine in human urine.