[Determination of L-carnitine, choline, taurine in infant formula milk powder by ultrafiltration tube cleaning and ultra-performance liquid chromatography-tandem mass spectrometry].

OBJECTIVE: To establish a method for simultaneous determination of L-carnitine, choline, taurin in infant by ultrafiltration tube cleaning and ultraperformance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). METHODS: The sample was dissolved in water and acid hydrolyzed, then adjusted pH with a sodium hydroxide solution. After ultrafiltration tube cleaning and centrifugation, the sample solution was separated on an amide column ACQUITY UPLC BEH Amide(2. 1 mm × 100 mm, 1. 7 µm) and detected by MS/MS under multiple reaction monitoring(MRM) mode. The quantification was performed by the internal standard calibration method. RESULTS: The linear ranges were 1. 00-500 µg/L for L-carnitine and choline, 10-1000 µg/L for taurine with correlation coefficients of 0. 999. The mean recoveries were 89. 7%-107. 4% with relative standard deviations(RSD, n = 6) were2. 6%-8. 1%. The detection limits of the method were 0. 812 mg/kg for choline, 0. 623 mg/kg for L-carnitine and 9. 34 mg/kg for taurine, respectively. CONCLUSION: This method is simple, accurate, reproducible and sensitivity.