基质固相分散-超高效液相色谱-质谱检测器测定牛奶中9种类固醇激素残留

Determination of nine estrogenic steroids in milk using matrix solid phase dispersion-ultra performance liquid chromatography with mass spectrometric detector

利用基质固相分散技术（MSPD）,建立了超高效液相色谱-质谱检测器（MSD）同时分析牛奶中9种类固醇激素残留的方法。便携式MSD的灵敏度和准确度优于紫外检测器;相比传统的质谱仪,MSD不需质谱参数优化,操作简便,开机抽真空时间短（只要5 min）,即开即用。分别考察了流动相比例、萃取溶剂和固相萃取小柱净化对MSD灵敏度和牛奶样品基质效应的影响。结果表明,MSD正离子模式对吸电子基团化合物的灵敏度更高,受外界条件影响大。经MSPD净化后,9种类固醇激素的基质效应由84%~160%降低为80%~121%。方法学研究结果表明,9种类固醇激素的日内精密度和日间精密度分别为0.87%~1.78%和1.82%~3.79%,加标回收率为68.7%~94.7%,相对标准偏差（RSD）小于10%,方法检出限（LOD）为0.5~10μg/kg,定量限（LOQ）为2~20μg/kg。该方法适合日常大批量样品的检测。

An analytical method for the multiresidue determination of nine estrogenic steroids in milk was developed by modified matrix solid phase dispersion（MSPD）purification and ultra performance liquid chromatography（UPLC） with mass spectrometric detector（MSD）. The sensitivity and accuracy of MSD were better than that of ultraviolet detector. In comparison with traditional mass spectrometry,the merits of MSD were simpler in operation and shorter in starting time（5 min）. The results showed that the limits of detection of the compounds with nucleophilic substitution were high in positive ion mode of MSD and were easily affected by environmental conditions. The matrix effects of milk samples reduced from 84%-160% to 80%-121% after MSPD purification. The intraday precision and interday precision of the nine estrogenic steroids were 0. 87%- 1. 78% and 1. 82%- 3. 79%,respectively. The average recoveries were 68. 7%-94. 7%,and the relative standard deviations（RSDs）were less than 10%. The limits of detection（LODs）were 0. 5- 10 μg / kg. The limits of quantification（LOQ）were 2- 20μg / kg.