超高效液相色谱-串联质谱法检测渔用饲料中氯霉素类药物

Determination of phenicols in fish formula feed by UPLC - MS /MS

采用超高效液相色谱-串联质谱仪（UPLC-MS／MS）同时快速测定鱼用配合饲料中的氯霉素、甲砜霉素和氟苯尼考3种药物。样品由乙酸乙酯2次提取，经旋蒸浓缩、流动相溶解、正己烷净化后，采用超高效液相色谱C18柱，以5mmol/L乙酸铵溶液-甲醇作流动相梯度洗脱分离，电喷雾负离子多反应监测模式（MRM）检测，内标法定量。氯霉素和氟苯尼考的定量限均为0．30μg/kg，线性范围均为0．20～50．0μg／L；甲砜霉素的定量限为0．5μg／b，线性范围为0．5-50．0μg／L。氯霉素在0．5、1．0、4．0μg／kg和甲砜霉素、氟苯尼考在2．0、10．0、50．0μg／kg的添加水平上的加标回收率为79．8％-102．5％，所有测定结果的日内和日间相对标准偏差（RSD）均小于15％。该方法简便快捷，准确度和精密度高，能够满足鱼用配合饲料中氯霉素类药物同时检测的要求。

A method was developed for simultaneous determination of ehloramphenicol, thiamphenicol and florfenicolresidues in fish formula feed by using ultra - high performance liquid chromatography - tandem mass spectrometry （UPLC -MS/MS）. The homogenized samples were extracted twice with ethylacetate and dried by evaporator, redis- solved into 2 mL mobile phase, and then cleaned by n -hexane. The targeted compounds were separated on C18 （2.1 mm ×50mm, 1.7μm）column by using 5 mmol/L ammonium acetate solution -methanol as mobile phase. Multiple reaction monitoring （MRM） with electrespray ionization in positive mode was used for detection. Quantitation limit for chloramphenicol and florfenicol were 0.30 μg/kg with good linearity ranging from 0.20 - 50.0μg/L, and quantita- tion limit for thiamphenicol was O. 50 μg/kg with good linearity ranging from 0.50 - 50.0μg/L. Recoveries spiked in negative samples at the levels of 2.0 -50.0μg/kg were 79.8% - 102.5%. The relative standard deviations（RSD） for all tests were less than 15%. With the advantages of simplicity, rapidity, high accuracy and precision, this meth- od could be suitable for the rapid detection of phenicols residue in fish formula feed.