液相色谱－串联质谱法测定牛奶中11种光引发剂残留量

摘要

A method for the qualitative and quantitative determination of 11 photoinitiators residues in milk by liquid chroma-tography-tandem mass spectrometry (LC-TMS) was developed.The samples were extracted with acetonitrile after being precipi-tated by Carrez reagent, and then cleaned by HLB solid phase extraction cartridge .The analytes were eluted by acetonitrile , and then reconstituted by 50%acetonitrile aqueous solution after being dried by nitrogen gas .LC-TMS was used for the determination. The analytes were determined by the mode of electro -spray ionization (ESI), positive ion scan, and multiple reaction monitoring (MRM), and internal standard method for the quantification of 7 photoinitiators and external standard method for the quantification of other 4 photoinitiators were used.Eleven photoinitiators within the concentration range of 5.00~200μg/L showed good linear re-lationship with the correlation coefficient of more than 0.990.All the lowest limits of the quantitative determination were 1.00 μg/kg.The recoveries of 11 photoinitiators were between 74.3%and 112% when the adding concentrations were 1.00~100 μg/kg, and the relative standard deviations varied from 0.57%to 16.3%.This method was simple, effective and sensitive, and suitable for the quantitative determination and confirmation of photoinitiator residues in milk .%　　建立了牛奶中11种光引发剂残留的定性和定量测定分析方法。样品经Carrez试剂沉淀蛋白质后，使用乙腈提取，HLB固相萃取柱净化，乙腈洗脱，洗脱液用氮气吹干后用50％乙腈水溶液定容，采用液相色谱-串联质谱进行测定。分析物采用电喷雾电离，正离子扫描，多反应监测（MRM）模式检测，其中7种光引发剂使用内标法定量，4种光引发剂使用外标法定量。11种光引发剂在5．00～200μg/L浓度范围内线性关系良好，相关系数均大于0．990。11种光引发剂的测定低限均为1．0μg/kg。在添加浓度1．00～100μg/kg范围内，加标回收率为74．3％～112％，相对标准偏差为0．57％～16．3％。本方法简便、有效、灵敏，适用于牛奶中光引发剂多残留的定量测定和确证。