[Determination of Cortisol in Saliva by Liquid Chromatography Tandem Mass Spectrometry].

Objective: To establish a liquid chromatography tandem mass spectrometry method to determine the cortisol in saliva. Methods: Take 0.5 ml saliva sample into a 2 ml centrifuge tube, add excess sodium chloride and 1ml acetonitrile to it, then vortex for 3 min, centrifuge for 10 min at 15 000 r/min, and take 800 μl of the upper layer to another centrifuge tube. Finally, the sample was concentrated by a vacuum concentrator and brought to 200 μl with the initial mobile phase. Then, the sample was analyzed by liquid chromatography tandem mass spectrometry. The target compound was quantified by external standard curve method. Results: The linear range of the method was 0.02-5.00 ng/ml, r=0.999 9, the method limit of the detection was 0.002 ng/ml, the method limit of quantitative was 0.02 ng/ml, and the spiked recoveries were 89.60%-98.60%. The intra-assay precision was 1.90%-3.30%, and the inter-assay precision was 4.20%-9.00%; samples could be stored at -20 °C for at least 14 days. The determination of cortisol could not be interfered by other endogenous substances in the sample. Conclusion: The method is simple in pretreatment, high sensitivity, good reproducibility and good recovery, and it is suitable for the quantitative analysis of cortisol in saliva for normal and occupationally stressed populations.目的： 建立测定唾液中皮质醇的液相色谱-质谱检测方法。 方法： 取0.5 ml唾液样品到2 ml离心管，并向其中加入过量氯化钠和1 ml乙腈，涡旋震荡3 min，15 000 r/min条件下离心10 min，取上层液体800 μl至另一离心管。样品经过真空浓缩仪浓缩并用初始流动相定容到200 μl后进仪器分析。利用外标标准曲线法对目标化合物进行定量。 结果： 该方法的线性范围为0.02~5.00 ng/ml，r=0.999 9，方法检出限为0.002 ng/ml，方法定量下限为0.02 ng/ml，加标回收率为89.60%~98.60%，批内精密度为1.90%~3.30%，批间精密度为4.20%~9.00%；样品在-20 ℃条件下可放置14 d；样品中的其他内源性物质不干扰皮质醇的测定。 结论： 该方法前处理简单，灵敏度高，重现性和回收率好，适用于正常人群和职业紧张人群唾液中皮质醇的定量分析。.