Abstract: 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, 3.5 μm) using gradient elution with a mobile phase containing 0.1% (V/V) formic acid in water and acetonitrile. The chromatographic separation was completed within 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 (R2) 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.

Key words: high performance liquid chromatography-tandem mass spectrometry, infant formula for special medical purposes, taurine

摘要： 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，3.5 μm）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（R2＞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。

关键词: 高效液相色谱-串联质谱法, 特殊医学用途婴儿乳粉, 牛磺酸