Headspace sampling and gas chromatographic-mass spectrometric determination of amphetamine and methamphetamine in betel

Abstract

A hot headspace sampling (HS) and gas chromatographic-mass spectrometric method (GC-MS) for the determination of amphetamine (AP) and methamphetamine (MA) in betel is described. The method uses potassium carbonate to alkalize the aqueous matrix and to salt-out the analytes prior to HS. The complicated matrices necessitate the separate analysis of betel nut, piper betel, and red slaked lime, which are the three major parts of a finished betel product. Qualitative identification is aided by the mass spectrum provided by the proposed method. The limits of quantitation vary from 0.02 to 1.20 μg/ml. Precisions calculated for the 5 and 50 μg/ml concentration range are ca. 20%. The method is simple, rapid, solventless, and requires only a small amount of sample. It may serve as a screening protocol for the determination of AP and MA in betel. © 1995.