Abstract: Objective To study the content variation of selegiline and its metabolites in urine, and based on actual cases, to explore the feasibility for the identification of methamphetamine abuse and selegiline use by chiral analysis. Methods The urine samples were tested by chiral separation and LC-MS/MS method using CHIROBIOTICTM V2 chiral liquid chromatography column. The chiral analysis of methamphetamine and amphetamine were performed on the urine samples from volunteers of selegiline use and drug addicts whom suspected taking selegiline. Results After 5 mg oral administration, the positive test time of selegiline in urine was less than 7 h. The mass concentrations of R（-）-methamphetamine and R（-）-amphetamine in urine peaked at 7 h which were 0.86 ?滋g/mL and 0.18 ?滋g/mL and couldn’t be detected after 80 h and 168 h, respectively. The sources of methamphetamine and amphetamine in the urine from the drug addicts whom suspected taking selegiline were analysed successfully by present method. Conclusion The chiral analysis of methamphetamine and amphetamine, and the determination of selegiline’s metabolites can be used to distinguish methamphetamine abuse from selegiline use.

Key words: forensic toxicology, methamphetamine, amphetamine, selegiline, chiral analysis, LC-MS/MS, urine