title: [Trimethylsilylation of testosterone, epi-testosterone and determination of their ratio in urine by GC-MS].
abstract: The trimethylsilylation of testosterone and epitestosterone was discussed in detail in this report. Both derivative conditions under which testosterone and epi-testosterone were prepared into TMS-derivatives in the presence of mercaptoethanol as an antioxidizing agent and method for the analysis of the ratio of testosterone to epi-testosterone in urine, based on GC-MS, had been established. The conditions of detection were: carrier gas was helium, derivatives were separated with SE-54 fused silica capillary column, using temperature program and detected by using multiple ion detection mode in which the ion of m/z 432 was the monitoring ion. The method is rapid, sensitive and specific. For the ratio of testosterone to epi-testosterone (testosterone: 20 ng/microliters), there is a linearity between ratio 1:1 and 10:1 (r = 0.998), the limit of detection for testosterone and epi-testosterone is 1 ng, and the minimum concentration of detection in urine is 8 ng/ml.
authors.affiliation: China Pharmaceutical University, Nanjing.
authors.forename: Y W
authors.initials: YW
authors.lastname: Yang
authors.forename: R J
authors.initials: RJ
authors.lastname: Wu
mesh_terms: D000975:Antioxidants; D004845:Epitestosterone / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D008623:Mercaptoethanol; D013739:Testosterone / Q000652:urine*; D014297:Trimethylsilyl Compounds
chemical_list: D000975:Antioxidants; D014297:Trimethylsilyl Compounds; D013739:Testosterone; D004845:Epitestosterone; D008623:Mercaptoethanol