利用UPLC-MS/MS测定牛奶中2种青霉素类药物的残留量

Siimultaneou determination of ampicillin and penicillin gresidues in dairy by ultra pepformance liquid chromatograph tandem mass spectromety

建立了一种应用超高效液相色谱-电喷雾串联三重四极杆质谱的方法、快速准确检测牛奶中氨苄青霉素及青霉素G残留量。试样经乙腈除去蛋白,离心取上清液,经氮气吹干后,用pH值为4.5的磷酸盐缓冲溶液溶解定容后,经HLB固相提取小柱净化和富集,在优化选择的色谱及质谱条件下,采用多反应监测进行定量。结果表明:采用Waters ACQUITY UPLC BEH C18色谱柱分离,以含有体积分数为0.1%甲酸的水溶液和乙腈为流动相进行梯度洗脱,仪器检出限为1.0～2.0μg/kg,在1～100μg/kg的线性范围内,相关系数r为0.999以上,回收率为81.7%～102.8%。该方法可准确快速测定牛奶中氨苄青霉素及青霉素G类药物的质量分数,结果准确可靠,重复性好,灵敏度高。

A HPLC-MS/MS method was developed for the simultaneous determination of Ampicillin and Penicillin G in milk. Isolation of Ampicillin and Penicillin G from milk matrices was performed with acetonitrile to remove the protein and then centrifugaed at 2 000 rpm/ min. For clean-up and concentration,sohd phase extraction （SPE）with HLB cartridges were used, than the good results were obtained by the analytical method of MRM with optimal parameters of Chromatograph and Mass. LC analysis was performed on Waters ACQUITY UPLC BEH C18 （2.1min× 50mm,LD,1.71μm）colunm and using acetonirile and water（0.1% formic acid） as mobile phase,the limit of detection was 1.0-2.0 μg/kg,the linear range was from 1.0 to 100 μg/kg with correlation coefficients （r）above 0.999,the recoveries for tetracycline was 81.7% -102.8%.This method can be applied for the determination of Ampicillin and Penicillin G in milk.