Analysis of aliphatic amines in air samples by HPLC with electrochemical detection

A method was developed for the analysis of primary aliphatic amines by high performance liquid chromatography coupled with electrochemical detector. The electrochemical oxidation of aliphatic amines derivatized with 2,5-dihydroxybenzaldehyde was investigated at porous graphite electrodes. The derivatization reactions were performed off-line, before the chromatographic separation. The compounds were separated on a reversed phase column with a methanol-acetonitrile-phosphate buffer and detected setting at an oxidation potential of +0.5 V. The influence of the mobile phase buffer concentration and pH on the detector response was also studied. The derivatization was shown to be quantitative and the response linear between 50 and 200 ng/ml. The method is sensitive, selective and could be applicable for the assay of volatile amines in the field of environmental toxicology and also for biological monitoring after occupational exposure.