Abstract:In this study, an ultrahigh liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of biotin content in infant formulas for special medical purposes. Samples were hydrolyzed with 0.2 mol/L phosphoric acid at 121 ℃ for 30 min before extraction and purification by a biotin immunoaffinity column. The analyte was separated on an acquity UPLC BEH C18 column (100 mm×2.1 mm, 1.7 μm) and eluted with the mobile phase of acetonitrile -0.1% formic acid in a gradient mode. Analyses were performed by the MS/MS system with electrospray ionization (ESI) in a multiple-reaction monitoring (MRM) mode and an internal standard. Under the optimized conditions, a good linear relationship was obtained for biotin in the range of 0.50~50.00 ng/mL (R2=0.9986), with a detection limit of 0.75 μg/100 g. The relative standard deviation of the biotin in the infant formulas for special medical purposes was 0.42%~4.77%, with the recoveries of the spiked samples at three levels were 97.27%~102.06%. The method has several advantages (simple sample processing, high sensitivity and short analysis cycle), therefore, can meet the requirements for determining the biotin content in infant formulas for special medical purposes, providing strong technical support for enterprise quality control and government supervision.
