Abstract: The aim of this study was the development of a method for the simultaneous determination of 3-monochloropropane-1,2-diol esters (3-MCPDEs) and glycidyl esters (GEs) in infant formula milk powder. Commercial infant formulas available on the Chinese market (n = 30) were analyzed for 3-MCPDEs and GEs by gas chromatography-mass spectrometry (GC-MS). Under the optimized conditions, 3-MCPDEs and GEs showed good linearity in the concentration range of 0.050?0.80 mg/L with correlation coefficient (R2) larger than 0.998. The mean recoveries from spiked samples were in the range of 81.4%?86.2% and 94.5%?101.1% with relative standard deviations (RSDs) ranging from 4.42% to 4.84% and from 4.46% to 6.12% for 3-MCPDEs and GEs, respectively. The limit of detection (LOD) of the proposed method was 30 μg/kg for both 3-MCPDEs and GEs. This method showed the advantages of high sensitivity, and accuracy, and could be suitable for the simultaneous detection of 3-MCPDEs and GEs in infant formula milk powder. In the 30 infant formula samples, levels of 3-MCPDEs and GEs ranged from 50.0 to 207.8 μg/kg and from 50.0 to 480.0 μg/kg with an average of 98.0 and 208.1 μg/kg, respectively.

Key words: isotope internal standard-gas chromatography-mass spectrometry, 3-monochloropropane-1,2-diol esters, glycidol esters, infant formula powder, quantitative determination