Chemistry Department, Lomonosov Moscow State University, Leninskie Gory 1-3, 119991 Moscow, Russia.
Drug Test Anal. 2011 Apr;3(4):263-7. doi: 10.1002/dta.221. Epub 2010 Dec 29.
The method of high sensitive gas chromatographic/time-of-flight mass-spectrometric (GC/TOF-MS) analysis of steroids was developed. Low-resolution TOF-MS instrument (with fast spectral acquisition rate) was used. This method is based on the formation of the silyl derivatives of steroids; exchange of the reagent mixture (pyridine and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA)) for tert-butylmethylether; offline large sample volume injection of this solution based on sorption concentration of the respective derivatives from the vapour-gas mixture flow formed from the solution and inert gas flows; and entire analytes solvent-free concentrate transfer into the injector of the gas chromatograph. Detection limits for 100 µl sample solution volume were 0.5-2 pg/µl (depending on the component). Application of TOF-MS model 'TruTOF' (Leco, St Joseph, MO, USA) coupled with gas chromatograph and ChromaTOF software (Leco, St Joseph, MO, USA) allowed extraction of the full mass spectra and resolving coeluted peaks. Due to use of the proposed method (10 µl sample aliquot) and GC/TOF-MS, two times more steroid-like compounds were registered in the urine extract in comparison with the injection of 1 µl of the same sample solution.
建立了一种用于甾体化合物的高灵敏度气相色谱/飞行时间质谱（GC/TOF-MS）分析方法。使用了低分辨率 TOF-MS 仪器（具有快速谱图采集速度）。该方法基于甾体化合物的硅烷基衍生物的形成；试剂混合物（吡啶和 N,O-双（三甲基硅基）三氟乙酰胺（BSTFA））的交换；基于溶液从溶液和惰性气流形成的蒸气-气流混合物中的各自衍生物的吸附浓缩，进行大体积在线进样；以及将整个分析物无溶剂浓缩转移到气相色谱仪的进样器中。对于 100µl 样品溶液体积，检测限为 0.5-2pg/µl（取决于成分）。将配备有 ChromaTOF 软件（Leco，密苏里州圣约瑟夫）的 TOF-MS 模型“TruTOF”（Leco，密苏里州圣约瑟夫）与气相色谱仪联用，允许提取全质谱并解析共洗脱峰。由于使用了所提出的方法（10µl 样品等分试样）和 GC/TOF-MS，与注射相同的 1µl 样品溶液相比，在尿提取物中登记到的甾体样化合物增加了两倍。
