RAPID GAS-CHROMATOGRAPHIC PROFILING AND SCREENING OF BIOLOGICALLY-ACTIVE AMINES

An efficient method is described for the simultaneous determination of 57 amines including volatile aliphatic amines, nonvolatile polyamines and catecholamines present in aqueous samples. The method is based on two-phase isobutyloxycarbonylation (isoBOC) with a pH shift. In 1.0 M phosphate buffer at pH 7.5, phenolic hydroxyl groups were allowed to react with isobutyl chloroformate in the dichloromethane phase, and su bsequently pH of the aqueous phase was increased to 12.0 for the react ion of basic amino functions. The resulting N(O)-isoBOC amines were re covered by solid-phase extraction using Chromosorb P in normal phase p artition mode, with subsequent tert.-butyldimethylsilylation of the re maining hydroxyl groups for gas chromatographic analysis. Using this c ombined procedure, linear responses were obtained in the concentration range of 0.2-12 ppm, with correlation coefficients varying from 0.945 to 0.999 for most of the amines studied except for 5-methoxytryptamin e (0.864). Temperature-programmed retention index (I) sets as measured on DB-5 and DB-17 dual-capillary columns of different polarity were c haracteristic of each amine and thus, useful in the screening for amin es by computer I matching. When applied to saliva samples, the present method allowed rapid screening for each spiked amine and unspiked pol yamines such as 1,3-diaminopropane, putrescine, cadaverine and spermid ine. (C) 1997 Elsevier Science B.V.