高效液相色谱-串联质谱法测定特殊医学用途婴儿乳粉中牛磺酸的含量

Determination of Taurine Content in Infant Formula for Special Medical Purposes by High Performance Liquid Chromatography-Tandem Mass Spectrometry

建立高效液相色谱-串联质谱法测定特殊医学用途婴儿乳粉中牛磺酸含量的分析方法。乳粉样品加水振荡15 min提取牛磺酸,5%偏磷酸沉淀样品中的蛋白质;采用SAX色谱柱(2.1 mm×150 mm,3.5μm)分离,以乙腈-0.1%甲酸水溶液体系为流动相进行洗脱,在电喷雾离子源正离子模式下电离,多反应模式监测。结果表明:牛磺酸在6.44 min出峰良好,在0.2~2.0 mg/L范围内线性良好(R^2>0.999),检出限为0.3 mg/100 g,定量限为1.0 mg/100 g;牛磺酸在低、中、高3个加标水平下的平均回收率为90.1%~102.4%,相对标准偏差为0.39%~3.30%。该方法具有灵敏度及准确度高、重复性和稳定性好等优点,适用于特殊医学用途婴儿乳粉中牛磺酸的有效检测。

An analytical method for the determination of taurine content in infant formula for special medical purposes has been established using liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).Samples were dissolved in double distilled water with constant shaking for 15 min for the purpose of taurine extraction,followed by protein precipitation with 5%metaphosphoric acid.The analyte was separated on an SAX column(2.1 mm×150 mm,3.5μm)using gradient elution with a mobile phase containing 0.1%(V/V)formic acid in water and acetonitrile.The chromatographic separation was completed withinax 9 min.Thereafter,the analysis was performed using an electrospray ionization source in the positive ion mode with multireaction monitoring.As a result,good linearity was observed in the concentration range from 0.2 to 2.0 mg/L with correlation coefficient(R^2)of greater than 0.999.The limit of detection(LOD)was 0.3 mg/100 g,and the limit of quantification(LOQ)was 1.0 mg/100 g.The average recoveries at three different spiked concentration levels ranged from 90.1%to 102.4%with relative standard deviation of 0.39%–3.30%(n=6).This method is applicable to analyze the taurine content in infant formula for special medical purposes,owing to its good sensitivity,recovery,repeatability and stability.