Abstract: Analysis of Nalbuphine and Its Metabolite in Human Urine by GC/MSShen Li; Xu Youxuan;Wu Yun;Wang Shan;Zhang Changjiu (China Doping Control Centre,National Research Institude of Sports Medicine,Beijing 100029,China) Abstract: A GC/MS method for the analysis of nalbuphine and its major metabolite is described. The urine sample was acid hydrolyzed,cleaned with diethyl ether,extracted with ethyl acetate/isopropanol,and derivazed with MSTFA-MBTFA. Nalbuphine and one of its metabolites were detected in urine sample within 1-36 h after administration of the drug. The method is fast and sensitive. Keywords: nalbuphine, metabolite, GC/MS