In this study, the direct analysis of doping agents in urine samples with no sample preparation by a modified paper spray mass spectrometry (PS-MS) methodology has been demonstrated for the first time. We have described a paper surface treatment with trichloromethylsilane using a gas-phase reaction to increase the ionization of target compounds. This approach was applied for the analysis of two classes of banned substances in urine samples: anabolic agents (trenbolone and clenbuterol) and diuretics (furosemide and hydrochlorothiazide). Under optimized conditions, the developed methods presented satisfactory repeatability, and an analysis of variance showed linearity without lack-of-fit. Highly sensitive detections as low as sub-nanogram per milliliter levels, which is below the minimum required performance levels proposed by the World Anti-Doping Agency, have been reached using the hydrophobic PS-MS analysis without any preconcentration and cleanup step.

中文翻译：

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使用疏水纸喷雾质谱法直接分析生尿中的掺杂剂。

在这项研究中，首次证明了通过改进的纸喷雾质谱法（PS-MS）直接分析尿液样品中的掺杂剂而不进行样品制备。我们已经描述了使用气相反应用三氯甲基硅烷进行纸表面处理以增加目标化合物的电离作用。该方法用于分析尿液样本中的两类违禁物质：同化剂（群勃龙和克仑特罗）和利尿剂（速尿和氢氯噻嗪）。在优化的条件下，开发的方法具有令人满意的可重复性，方差分析显示线性，且不缺乏拟合度。高度灵敏的检测低至每毫微纳克以下