免疫亲和固相萃取-超高效合相色谱-串联质谱法同时测定牛奶中6种玉米赤霉醇类化合物残留

建立了免疫亲和固相萃取（IAC-SPE）-超高效合相色谱-串联质谱（UPC²-MS/MS）同时测定牛奶中α-玉米赤霉醇、β-玉米赤霉醇、α-玉米赤霉烯醇、β-玉米赤霉烯醇、玉米赤霉烯酮和玉米赤霉酮残留的分析方法。样品用去离子水稀释，经IAC-SPE富集净化后，采用Waters ACQUITY UPC² Torus 2-PIC色谱柱（50 mm×3.0 mm，1.7 μm）分离，以超临界CO₂和0.1%（v/v）甲酸甲醇溶液为流动相，经梯度洗脱后在ESI^-模式下检测。经过稀释离心的牛奶样品采用免疫亲和柱净化后没有明显的基质效应，6种目标化合物在1~200 ng/mL范围内线性关系良好，相关系数（r²）≥0.9957；6种目标化合物在3个加标水平下的平均回收率为75.9%~106.5%，日内和日间精密度均≤11.4%。该法专属性好，操作简便，有机溶剂使用量小，与已有的样品测定方法比较更绿色环保，可用于牛奶中α-玉米赤霉醇、β-玉米赤霉醇、α-玉米赤霉烯醇、β-玉米赤霉烯醇、玉米赤霉酮和玉米赤霉烯酮的残留检测。

Simultaneous determination of six zeranols in milk samples by immunoaffinity solid phase extraction coupled with ultra-performance convergence chromatography-tandem mass spectrometry

A method was developed for the simultaneous determination of α-zearalanol, β-zearalanol, α-zearalenol, β-zearalenol, zearalenone and zearalanone residues in milk samples by ultra-performance convergence chromatography-tandem mass spectrometry (UPC²-MS/MS) after immunoaffinity column-solid phase extraction (IAC-SPE). The sample was diluted with deionized water and cleaned with IAC-SPE. The chromatographic separation was performed on an ACQUITY UPC² Torus 2-PIC column (50 mm×3.0 mm, 1.7 μm) using the mobile phases of supercritical carbon dioxide and methanol containing 0.1% (v/v) formic acid with gradient elution. The separated compounds were detected in negative electrospray ionization (ESI^-) mode. The results showed no significant matrix effect after cleaning by IAC-SPE. The calibration curves of the six compounds were linear in the range of 1-200 ng/mL (correlation coefficients (r²) ≥ 0.9957). The recoveries were 75.9%-106.5% in the three spiked levels, and the intra-day and inter-day precisions were no more than 11.4%. The method is specific, environment friendly, and is suitable for the rapid determination of α-zearalanol, β-zearalanol, α-zearalenol, β-zearalenol, zearalenone and zearalanone residues in milk samples.