[Determination of amphetamine and methamphetamine in human hair using gas chromatography/mass spectrometry]

The authors present a procedure of concurrent identification and quantification of amphetamine and metamphetamine in human hair. The method involves rinsing of the hair (distilled water 55 degrees C, 0.1 M hydrochloric acid, distilled water to neutral reaction, methanol) drying in air, homogenization by cutting (1-2 mm long), alkaline hydrolysis (20 mg hair, 1 ml 1 M sodium hydroxide, 55 degrees C, 120 min.), neutralization with 1 M hydrochloric acid to pH = 7, extracting benzoylation with 2,3,4,5,6-pentafluorobenzoyl chloride (0.3 ml 1 M sodium hydroxide, 4 ml cyclohexane, 30 ul cyclohexylamine in cyclohexane of a concentration of 20 ng/ul--internal standard, 50 ul aqueous solution of triethylamine hydrochloride concentration of 100 mg/ml--reaction catalyst and 10 ul of derivation agent 2,3,4,5,6-pentafluorobenzoyl chloride dilution 1:10, shaking for 5 mins. by hand and leaving to stand for 10 mins.), centrifugation (5 mins., 3000 rotations/min.), collection of 2 ml cyclohexane layer, its evaporation at 40 degrees C in nitrogen atmosphere and dilution with 100 ul cyclohexane. The derivated extract was subjected to analysis by the GC-MS method. The procedure was used for segmentation analysis of hair of two subjects abusing metamphetamine for prolonged periods. The revealed concentrations varied within the range of 0.99-5.25 mg/kg metamphetamine and 0.13-0.73 mg/kg amphetamine.