UPLC-MS/MS法同时测定牛奶中青霉素G及青霉噻唑酸

利用超高效液相色谱-串联质谱法(UPLC-MS/MS)同时测定牛奶中的青霉素G和青霉噻唑酸。样品经乙腈沉淀蛋白,上清液氮气吹干后,用水溶解,加入正己烷萃取除去脂肪;提取液经ACQUITYUPLCBEHC18柱分离,乙腈-1mmol/L乙酸铵+0.1%甲酸水溶液洗脱。青霉素G和青霉噻唑酸的检出限分别为1、2μg/kg,定量限分别为5、10μg/kg。在10～100ng/mL浓度范围内线性良好,相关系数均大于0.999,牛奶中的加标回收率在92%～103%,精密度(RSD,n=3)范围在2%～4%。

Simultaneous determination of penicillion G and penicilloic acid in milk by UPLC-MS/MS

An ultra performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS) analysis method was established for simultaneous analysis of penicillion G and penicilloic acid in milk.The milk sample was precipitated with acetonitrile and the supernatant was dried under nitrogen,the residue was dissolved in water and then extracted with n-hexane.The sample extract was separated by ACQUITY UPLC BEH C18 column,using a mixture of 0.1% formic acid in water with 1 mmol/L ammonium acetate and acetonitrile as the mobile phase.The detection limits of penicillion G and penicilloic acid was 1,2 μg/kg.And the limits of quantitation were 5,10 μg/kg.The correlation coefficient were above 0.999 within the linear range of 10～100 ng/mL.The average recoveries were 92%～103%,the relative standard deviations(RSD,n=3) were 2%～4%.