超高效液相色谱-三重四极杆/线性离子阱复合质谱法测定鸡蛋中黏菌素残留的研究

Determination of Colistin Residue in Eggs by LC-QTRAP

关键词:  黏菌素  鸡蛋  残留  液相色谱-三重四极杆/线性离子阱复合质谱

Key words:  Colistin  Eggs  Residue  LC-QTRAP

摘要:

建立了鸡蛋中黏菌素残留检测的超高效液相色谱-三重四极杆/线性离子阱复合质谱方法（UPLC -QTRAP）。样品用25%甲醇提取后，正己烷去脂，固相萃取柱净化，上机测试。液相色谱条件：色谱柱为BEH C18（50 mm×2.1 mm，1.7 μm），流动相为0.5%甲酸水溶液+0.5%甲酸乙腈溶液，梯度洗脱，流速为0.4 mL/min，柱温为30 ℃，进样量为5 μL。质谱条件：电喷雾正离子源（ESI+），采用多反应监测-信息依赖扫描-增强子离子扫描（MRM-IDA-EPI）方式采集。结果表明：在鸡蛋中，黏菌素A和黏菌素B在20~800 ng/kg基质匹配标准溶液浓度范围内均呈现良好的线性关系，相关系数（R2）大于0.990；鸡蛋中黏菌素A和黏菌素B的定量限均为30 μg/kg，检测限为10 μg/kg。鸡蛋中黏菌素A和黏菌素B在30、150和300 μg/kg三个添加浓度平均回收率都在67.2％~106％之间，批内、批间RSD均小于20%。该方法定性准确、灵敏度高、简便快捷，回收率和精密度满足残留检测要求。

Abstract:

A LC-QTRAP method was established for the determination of Colistin residue in Eggs. The samples were extracted by water(25% methanol), the fat was removed by hexane, and purified with C18 SPE. LC conditions were as follows: the chromatography column is BEH C18 column of 50 mm×2.1 mm, 1.7 μm；mobile phase is water（0.5% formic acid）and acetonitrile（0.5% formic acid）; flow rate is 0.4 mL/min; column temperature is 30 ℃; injection volume is 5 μL. Mass spectrometry conditions were ESI+ and Multi-reaction Monitoring-Information Dependent Acquisition-Enhanced Product Ion (MRM -IDA - EPI) mode. The calibration curve of Colistin were good linear from 20 to 800 ng/kg in Eggs with the correlation coefficient R2 over 0.990. The limit of quantification was 30 μg/kg，and the limit of detection was 10 μg/kg. The average recoveries of Colistin from spiked Eggs at three concentrations of 30, 150 and 300 μg/kg were between 60%～120％, and intra- and inter-batch RSD were <20%.