Simultaneous Determination of Five Fat-Soluble Vitamins in Infant Formula Milk Powder by Ultra-high Performance Liquid Chromatography-Tandem Mass Spectrometry

A method was developed for simultaneous measurement of the levels of vitamins A, D₃, K₂, E, and β-carotene in infant formula milk powder using ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The calibration curves for the five fat-soluble vitamins showed good linearity within the concentration range of 1–800 ng/mL. The average recoveries at three spiked levels were between 92.0% and 108.0% with relative standard deviations (RSDs) ranging from 0.4% to 2.6%. The limits of quantification (LOQs) of this method were 12.5–125 μg/100 g. The proposed method was characterized by simple sample pre-treatment, high quantitative sensitivity, and good accuracy and precision.