液相色谱串联质谱法定量检测青花菜中L-硒甲基硒代半胱氨酸

Quantitaion of Methylselenocysteine in Broccoli Powder with Liquid Chromatography-Tandem Mass Spectrometry

建立了液相色谱串联质谱(LC-MS-MS)法测定青花菜中L-硒甲基硒代半胱氨酸(SeMC)含量的方法。植物样品经沸水提取,以甲醇-0.1%七氟丁酸水溶液(30∶70)为流动相,滤液经Waters Symmetry C18(50 mm×3.9 mm,5μm)分离,经在线电喷雾离子源(ESI)正离子化后,采用多反应离子监测方式(MRM)选择m/z184.0→(167.0,94.9)测定SeMC。SeMC的线性范围为0-200 mg/L,准确度在96%-114%之间,日内日间精密度(RSD)在±10%内。检出限为0.1 mg/kg。结果表明:本方法高效、准确,特异性强,样品处理简单,可准确定量富硒青花菜中的SeMC。

A HPLC-MS/MS method was established for the determination of methylselenocysteine （SeMC） content in broccoli powder. Broccoli powder samples were extracted with deionized water at 100℃ for 1 hour, filtered through 0.2μm filter, and then separated on Waters Symmetry C18 （ 150 mm × 3.9 mm, 5 μm） column with methanol -0. 1% heptafluorobutyric acid （30：70, V/V） as mobile phase, at a flow rate of 500 μL/min. Electrospray ionization source （ESI） was applied and operated in positive ion mode, and multiple reactions monitoring （MRM） mode was adopted. SeMC was quantified by monitoring the： ion transition of m/z 184.0→（ 167.0; 94.9）. The linear calibration curves were obtained over the concentration range of 0 - 200 mg/L for SeMC . The lowest detection limit （S/N = 3 ） was 0.1 mg/kg for SeMC. The spiking recov- ery of SeMC varied between 96% - 114% with in 10% of inter-and intra-day precision （RSD）.