建立了婴幼儿配方奶粉中氢化可的松和氟氢可的松醋酸酯激素残留的高效液相色谱-串联质谱（HPLC-MS/MS）测定方法。样品经水分散后以乙腈提取，氯化钠盐析，以N-丙基乙二胺（primary secondary amine，PSA）和中性氧化铝（Al2O3-N）净化，Waters XBridge C18色谱柱分离，电喷雾正离子扫描，多反应监测（MRM）模式检测，基质匹配标准溶液外标法定量。在优化条件下，目标化合物在3个加标水平（1.25、5.00、12.50 μg/kg）下的平均回收率为80.6%~102.1%，相对标准偏差（RSD）为1.64%~4.22%，方法检出限（LOD）为0.40 μg/kg，方法定量限（LOQ）为1.25 μg/kg。应用本方法对28批次婴幼儿配方奶粉进行测定，发现2批次样品检出氢化可的松。方法简便快速、灵敏度高、重现性好，能满足婴幼儿配方奶粉中氢化可的松和氟氢可的松醋酸酯激素残留的快速检测要求。

An analytical method was developed for simultaneous determination of hydrocortisone and fludrocortisone acetate in infant formulas using QuEChERS sample preparation with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The samples were dispersed by water, extracted with acetonitrile, salted out with sodium chloride, and then the extract was cleaned up with primary secondary amine (PSA) and aluminum oxide (Al2O3-N). The target compounds were separated on a Waters XBridge C18 column, determined using electrospray ionization (ESI) source in positive mode with the multiple reaction monitoring (MRM) acquisition mode and quantified with the matrix-matched external standard method. Under the optimal conditions, the average recoveries for the two hormones at three spiked levels (1.25, 5.00, 12.50 μg/kg) were in the range of 80.6%~102.1% with the relative standard deviations of 1.64%~4.22%. The limits of detection (LODs) were 0.40 μg/kg, and the limits of quantification (LOQs) were 1.25 μg/kg. This method was applied to analyze 28 batches of infant formulas, and hydrocortisone was found in two of them. The method is simple, rapid, sensitive, and reproducible, and can be applied to the rapid determination of hydrocortisone and fludrocortisone acetate in infant formulas.

湖北省自然科学基金项目（2018CFB340）；湖北省食品药品监督管理局科研项目(201602009)