Ameline Alice, Gheddar Laurie, Raul Jean-Sébastien, Kintz Pascal
Institut de médecine légale, 11 rue Humann, 67000 Strasbourg, France.
Institut de médecine légale, 11 rue Humann, 67000 Strasbourg, France.
J Chromatogr B Analyt Technol Biomed Life Sci. 2021 Jan 1;1162:122495. doi: 10.1016/j.jchromb.2020.122495. Epub 2020 Dec 15.
Letrozole is a reversible aromatase inhibitor, used in the treatment of hormone-dependent woman cancer. No indication for medical use is available for men. In recent years, several cases of doping with letrozole have been observed, especially among high level athletes. Aromatase inhibitors reverse the harmful effects (feminizing) of the abuse of anabolic androgenic steroids. Letrozole is included on the list of products prohibited in- and out-competition by the World Anti-Doping Agency, under section S4.1. The aim of the present work was to develop a specific method to identify letrozole in human hair of a male amateur athlete by LC-MS/MS and confirmation by LC-HRMS, after incubation of 20 mg of matrix in 1 mL of methanol. The chromatographic separation was performed using a reverse phase column HSS C18 with a gradient elution of 15 min (from 87% to 5% of formate buffer adjusted to pH 3). Linearity was observed from 1 to 1000 pg/mg (r = 0.9999), after spiking blank hair with the corresponding amounts of letrozole. The limit of detection was estimated at 0.5 pg/mg and the lower limit of quantification was the first point of the calibration curve, i.e. 1 pg/mg. The precision was lower than 20% and there was no interference with the analytes by chemicals or any extractable endogenous materials present in hair. Letrozole was identified in the male amateur athlete hair at 310 pg/mg (segment 0-2 cm) and 245 pg/mg (segment 2-4 cm).
来曲唑是一种可逆性芳香化酶抑制剂，用于治疗激素依赖性女性癌症。男性尚无医学用途的适应证。近年来，已观察到数例使用来曲唑进行兴奋剂检测呈阳性的案例，尤其是在高水平运动员中。芳香化酶抑制剂可逆转滥用合成代谢雄激素类固醇的有害影响（女性化）。来曲唑被世界反兴奋剂机构列入赛内和赛外禁用产品清单，属于S4.1类别。本研究的目的是开发一种特定方法，通过液相色谱-串联质谱法（LC-MS/MS）在一名男性业余运动员的头发中鉴定来曲唑，并通过液相色谱-高分辨质谱法（LC-HRMS）进行确证，将20mg基质在1mL甲醇中孵育后进行检测。使用反相柱HSS C18进行色谱分离，梯度洗脱15分钟（从87%至5%的pH 3甲酸缓冲液）。在空白头发中加入相应量的来曲唑后，观察到线性范围为1至1000pg/mg（r = 0.9999）。检测限估计为0.5pg/mg，定量下限为校准曲线的第一个点，即1pg/mg。精密度低于20%，头发中存在的化学物质或任何可提取的内源性物质对分析物均无干扰。在该男性业余运动员头发中，0-2cm段来曲唑含量为310pg/mg，2-4cm段为245pg/mg。
