Abstract: Objective To establish a method for the analysis of methcathinone in urine by gas chromatography-mass spectrometry （GC-MS）. Methods Proadifen hydrochloride （internal standard） and buffer solution （pH=9） were added into the urine samples, and methcathinone was extracted by ethyl acetate. The extract was volatilized in 50 ℃ nitrogen gas flow and the remnant was dissolved by methanol and analysed by GC-MS. Results The methcathinone in urine showed a good linear relationship in the mass concentration range of 0.02-2.00 μg/mL. The linear equation was y=0.301 9 x+0.018 9 （r=0.999 2）, and the detection limit was 0.01 μg/mL. The recoveries of methcathinone in urine was 96.4%-99.2%, with the intra-day precision of 5.8%-7.6% and the inter-day precision of 6.0%-8.1%. Conclusion The method is convenient and sensitive, which can be applied to the forensic identification of methcathinone in urine.

Key words: forensic toxicology, gas chromatography-mass spectrometry, urine, methcathinone