Abstract: Using gas chromatography-tandem mass spectrometry (GC-MS), an indirect method was established for the simultaneous detection of 3-chloropropanol esters (3-MCPDE) and glycidyl esters (GE) in infant formula for special medical purposes. The conditions for sample extraction and transesterification/hydrolysis were optimized and stable isotope dilution was used to improve the accuracy and precision of the method. The results showed that the method exhibited good linearity in the range of 0.005–2.000 μg/mL (R2 ≥ 0.999), together with a limit of detection (LOD) of 5 μg/kg and a limit of quantification (LOQ) of 25 μg/kg (both calculated based on the corresponding amount of chloropropanol). The recoveries of the analytes spiked in infant formula for special medical purposes at 25, 125 and 250 μg/kg were 88.5%–104.1%, and the relative standard deviations (RSDs) for six replication determinations were less than 15% (n = 6). The levels of 3-MCPDE and GE in three types of commercial infant formula for special medical purposes were below the maximum limits set by the EU.

Key words: infant formula for special medical purposes, 3-chloropropanol esters, glycidol esters, gas chromatography-mass spectrometry, isotope dilution

摘要： 采用气相色谱-串联质谱法，建立同时检测特殊医学用途婴幼儿配方食品中3-氯丙醇酯（3-chloropropanol esters，3-MCPDE）和缩水甘油酯（glycidol esters，GE）的间接测定方法。针对样品提取和酯交换水解2 个前处理条件进行优化，结合同位素稀释技术，提高检测方法的准确度和精密度。结果表明：该方法在0.005～2.000 μg/mL范围内线性良好（R2≥0.999），检出限为5 μg/kg，定量限为25 μg/kg（检出限和定量限均以相应的氯丙醇计）；以特殊医学用途婴幼儿配方食品为基质，分别添加25、125、250 μg/kg 3-MCPDE和GE进行加标实验，回收率为88.5%～104.1%，相对标准偏差低于15%（n=6），满足欧盟标准对特殊医学用途婴幼儿配方食品中3-MCPDE和GE的限量要求。

关键词: 特殊医学用途婴幼儿配方食品, 3-氯丙醇酯, 缩水甘油酯, 气相色谱-串联质谱, 同位素稀释