Highly sensitive analysis of methamphetamine and amphetamine in human whole blood using headspace solid-phase microextraction and gas chromatography–mass spectrometry

Abstract 

A simple and highly sensitive method for analysis of derivatized methamphetamine (MA) and amphetamine (AM) in whole blood was developed using headspace solid-phase microextraction (HS-SPME) and gas chromatography–mass spectrometry electron impact ionization selected ion monitoring (GC–MS-EI-SIM). A whole blood sample, deuterated-MA (d₅-MA), as an internal standard (IS), tri-n-propylamine and pentafluorobenzyl bromide were placed in a vial. The vial was heated and stirred at 90°C for 30min. Then the extraction fiber of the SPME was exposed at 90°C for 30min in the headspace of the vial while being stirred. The derivatives adsorbed on the fiber were desorbed by exposing the fiber in the injection port of a GC–MS. The calibration curves showed linearity in the range of 0.5–1000ng/g for both MA and AM. The time for analysis was about 80min per sample. In addition, this proposed method was applied to two autopsy cases where MA ingestion was suspected. In one case, MA and AM concentrations in the mixed left and right heart blood were 165 and 36.9ng/g, respectively. In the other case, MA and AM concentrations were 1.79 and 0.119μg/g in the left heart blood, and 1.27 and 0.074μg/g in the right heart blood, respectively.

Keywords: Highly sensitive, Methamphetamine, Amphetamine, Whole blood, HS-SPME, Pentafluorobenzyl bromide