中文摘要：

目的建立同时测定硒蛋氨酸（seMet）和硒胱氨酸（SeCys）含量的液相色谱一串联质谱法（LC—Ms—Ms）。方法色谱柱：Waters Symmetry C18（150mm×3.9mm，5μm）；流动相：甲醇＋0.1％七氟丁酸水溶液（35＋65），流速为500μl／min；以氮气为碰撞气，利用多反应离子监测方式测定SeMet（MRMm／z198.1→181.0，198.1→152.0）和SeCys（MRMm／z337.0→248.0，337.0→88.2）信号。结果SeCys和SeMet检出限分别为2．0ng／ml和0.5ng／ml：以198.1→181.0为定量分析离子对，SeMet的线性生回归方程为：y=707x＋990，r=0.9993；以337.0→248.0为定量分析离子对，SeCys的线性回归方程为：y=64.3z＋695，r=0.9999。结论该方法能够使2种含硒化合物在一次进样中实现完全分离和在线测定，能够满足快速准确检测SeCys和SeMet含量要求。

英文摘要：

Objective To establish the method of liquid chromatography-tandem mass spectrometry （LC - MS - MS） in order to determine selenoeystine （SeCys） and selenomethionine （SeMet）. Method The chromatographic column was Waters Symmetry C18 （ 150 mm× 3.9 mm, diameter 5 μm）. The mobile phase was methanol ＋ 0.1% heptafluorobutyric acid （35 ＋ 65 ） at a flow rate of 500μl/min. SeMet and SeCys were detected by monitoring the ion transition of m/z 198.1→181.0, 198.1→152.0 and 337.0→248.0, 337.0→88.2, with nitrogen as collision gas and using multiple reaction monitoring （MRM） mode. Results The determination limits of SeCys and SeMet were 2.0 and 0.5 ng/ml, respectively. The linear regression equations of SeMet and SeCys were y = 707x ＋ 990, r = 0.999 3 and y = 64.3x ＋ 695, r = 0.999 9, respectively. Conclusion SeMet and SeCys could be completely separated and determined for on-line in one injection by this method. The method could meet requirements of fast and accurate determination of SeMet and SeCys.