采用液相色谱-串联质谱法(LC-MS/MS)测定了水产品中结晶紫以及它的隐色代谢物残留。匀质后的水产品样品用乙腈和乙酸铵缓冲液提取,合并提取液,用二氯甲烷反提取,经中性氧化铝柱和PRS柱固相萃取净化,且不使用氧化铅柱在线氧化,色谱分离后直接进入串联质谱检测器。采用电喷雾正离子,多反应监测(MRM)模式检测。方法的检出限可达0.5ng/g,线性方程的相关系数r大于0.99,添加样品平均回收率为77.6%~93.8%。相对标准偏差均小于8.2%。
A liquid chromatography tandem mass spectrometry (LC-MS/MS) method was described for determination of residues of crystal violet (CV) and its metabolite leucocrystal violet (LCV) in aquatic products. The targeted analytes were extracted from homogenized samples with a mixture of acetonitrile and ammonium acetate buffer, partitioned against methylene chloride, and purified on tandem neutral alumina and PRS SPE cartridges. Chromatographic Separation was achieved by using ZORBAX SB-C18 column with an isocratic mobilc phase consisting of ammonium acetate(0. 05 mM) and acetonitrile(10/ 90,V/V) without post-column oxidation with PbO2. Identification and quantification were performed using multiple reaction monitoring(MRM) with one precursor ion and two productions for each analyte and electrospray ionization in positive mode. The detection limit was 0. 5 ng/g. and correlation coefficient of linear regression equations were above 0. 99. Recoveries were in the range of 77. 6%~93.8% and the RSD were less than 8. 2 %.