Gas Chromatography-High-Resolution Mass Spectrometric Method for Determination of Methamphetamine and its Major Metabolite Amphetamine in Human Hair

Gas chromatography-high-resolution mass spectrometric (GC-HRMS) method is presented for the qualitative and quantitative analysis of methamphetamine (MA) and its major metabolite, amphetamine (AMP), in human hair. The method procedure involves decontamination of hair with distilled water and acetone, acidic hydrolysis and extraction in the presence of the internal standard, and GC-HRMS selective ion monitoring (SIM) analysis. The limits of detection (LOD) were 9 pg/mg for MA and 21 pg/mg for AMP using a 30-mg hair sample, and the SIM responses were linear with coefficients of correlation ranged from 0.9998 to 0.9999. The recoveries were found to be 91.1–92.3%. By using HRMS (resolution of 5000), detection sensitivity is improved because of the elimination of the biological background, and the LODs for MA and AMP were 2.4–4.4 times lower than those of low-resolution MS. The GC-HRMS method was successfully applied to the analysis of cosmetically treated hair, which is difficult to analyze with the conventional method.