液相色谱-三重四极杆/线性离子阱复合质谱技术检测牛可食性组织中莫昔克丁的残留

The Research of Moxidectin Residues in Cattle Edible Tissues by LiquidChromatography-Quadruple/Linear Ion Trap Mass Spectrometry

建立了一种可准确定性定量检测4种牛可食性组织中莫昔克丁残留的液相色谱-三重四极杆/线性离子阱(LC-Qtrap)复合质谱分析技术。牛肌肉、肝脏、肾脏和脂肪样品经乙腈提取,高速离心去除蛋白质等杂质,C18柱净化。以0.1%甲酸水溶液和0.1%甲酸乙腈溶液为流动相进行洗脱,在BEH C18色谱柱上实现分离,在电喷雾正离子(ESI+)模式下,用多反应监测联合信息依赖性采集与增强子离子扫描(MRM-IDA-EPI)模式检测,基质匹配标准溶液外标法定量。结果表明:莫昔克丁在牛肌肉和牛肾脏1~100 ng/mL的基质匹配浓度范围内;在牛肝脏1~200 ng/mL的基质匹配浓度范围内和在牛脂肪1~1000 ng/mL的基质匹配浓度范围内均呈现良好的线性关系,相关系数(R 2)均大于0.990;在4种牛可食性组织中莫昔克丁的定量限均为2μg/kg。莫昔克丁在牛肌肉2~40μg/kg、牛肝脏2~200μg/kg、牛肾脏2~100μg/kg和牛脂肪2~1000μg/kg添加浓度水平上的回收率范围为65.6%~115%;批内与批间相对标准偏差均小于15%。该方法具有简便快速、灵敏度高、定性准确,重复性好等特点,可以满足上述组织中莫昔克丁残留检测的要求。

A liquid chromatography-quadruple/linear ion trap mass spectrometry(LC-Qtrap MS)method with good accuracy was established for the determination of moxidectin residues in 4 kinds of cattle edible tissues.Moxidectin was extracted from cattle muscle,liver,kidney and fat with acetonitrile,and the protein was deposited by high speed centrifugation.Then the sample solutions were purified with C18 column.The mobile phase were water(0.1%formic acid)and acetonitrile(0.1%formic acid),and the samples were separated by BEH C18 column.LC-Q-trap MS analysis was performed by positive ion electrospray ionization(ESI+)applying the detection mode of MRM-IDA-EPI.The method was quantified by matrix matched standard curves.Good linearities of the calibration curves were obtained with the range of 1~100 ng/mL in cattle muscle and kidney,with the range of 1~200 ng/mL in cattle liver,and with the range of 1~1000 ng/mL in cattle fat,the correlation coefficient R 2>0.990.The limit of quantification of moxidectin was 2μg/kg.The recoveries of moxidectin residues were 65.6%~115%,for cattle muscle at the concentrations of 2~40μg/kg,cattle liver at the concentrations of 2~200μg/kg,cattle kidney at the concentrations of 2~100μg/kg,and for cattle fat at the concentrations of 2~1000μg/kg.The intra-batch and inter-batch variation coefficients were both less than 15%.With high sensitivity,good accuracy and repeatability,the method can be applied for the determination of moxidectin residues in 4 kinds of cattle edible tissues.