Application of a Solid-Phase Microextraction Technique for the Detection of Urinary Methamphetamine and Amphetamine by Gas Chromatography

Abstract

We describe here a simple and rapid detection of methamphetamine (MA) and amphetamine (AP) simultaneously in urine by gas chromatography (GC) using a solid-phase micro-extraction (SPME) technique. We used an SPME fiber (Polydimethylsiloxane thickness; 100μM) with a fiber holder for manual use. After addition of urine (1.0 ml), NaCI(0.5g) and 1-phenylbutylamine (5.0 μg, 1-PB, internal standard) into a vial (1.5 ml), we adjusted the sample to pH12 with NaOH (10N) and then rapidly sealed it with a teflon-coated septum. After immersion of the SPME fiber in the sample for 20 min, and then washing promptly in NaOH-H3BO4 buffer (pH12), the SPME needle was inserted into the injection port of the GC and the fiber extruded. Each peak of MA, AP and 1-PB was clearly separated. Linearity of AP and MA were in the ranges of 0.25–10 and 0.1–1.0 μg/ml, respectively. This SPME technique, applicable without using organic solvents, is simple and rapid. It is, therefore, useful for the practical detection of MA and AP in urine.