超高效液相色谱法和液相色谱-串联质谱法测定食品中奥比沙星残留量

Determination of Residual Amounts of Orbifloxacin in Food by UHPLC and LC-MS/MS

食品样品用乙腈和磷酸盐缓冲溶液提取,经正己烷脱脂和HLB固相萃取柱净化处理后,用超高效液相色谱(UHPLC)-荧光检测器进行测定,阳性结果再经液相色谱-串联质谱法(LC-MS/MS)进一步确证。两种方法的线性范围分别为0.005～0.250,0.002～0.300 mg.L-1,检出限(3S/N)分别为0.005,0.002 mg.kg-1,回收率分别为80.2%～98.4%,74.5%～93.0%,相对标准偏差(n=10)均小于11.0%。

The food sample was extracted with acetonitrile and phosphate buffer solution,and defatted with n-hexane and purified by passing through HLB SPE column.The eluate obtained was determined by UHPLC with fluorescence detector,and positive results were further confirmed by LC-MS/MS.Linearity ranges of orbifloxacin obtained by the two method were found to be in the ranges of 0.005-0.250 mg·L-1（by UHPLC） and 0.002-0.300 mg·L-1（by LC-MS/MS）,and values of detection limits（3S/N） found were 0.005 and 0.002 mg·kg-1 respectively.Values of recovery ranged from 80.2%-98.4%（for UHPLC） and from 74.5%-93.0%（for LC-MS/MS）,were found with RSD′s（n=10） less than 11.0%.