牛、羊奶中莫昔克丁残留高效液相色谱荧光检测方法的建立

Determination of Moxidectin residue in milk by high performance liquid chromatography-fluorescence detection method

关键词:  牛、羊奶  莫昔克丁  残留  高效液相色谱荧光法

Key words:  milk  Moxidectin  residue  HPLC-FLD

摘要:

建立了适用于牛、羊奶样品中莫昔克丁残留的高效液相色谱荧光检测方法。以乙腈为提取液，C18固相萃取柱净化，并用N-甲基咪唑-乙腈(1+1，V/V)和三氟乙酸酐-乙腈(1+2，V/V)进行衍生化。乙腈+水(90+10，V/V)为流动相，荧光法定量。经测定，该方法对牛、羊奶中莫昔克丁的检测限为2 μg/kg，定量限为5 μg/kg。空白牛、羊奶中标准品莫昔克丁添加量分别为5、20、40和80 μg/kg时，牛奶中莫昔克丁平均回收率范围为75.5%～110%，其批内变异系数小于738%，批间变异系数小于7.87%；羊奶中莫昔克丁平均回收率范围为77.5%～95.6%，其批内变异系数小于5.06%，批间变异系数小于5.92%。该方法准确性强、灵敏度高，适用于牛、羊奶中莫昔克丁的快速检测。

Abstract:

A method for determination of moxidectin residue in bovine and ovine milk by high performance liquid chromatography-fluorescence detection (HPLC-FLD) was established. The analyte were extracted with acetonitrile and cleaning with C18 solid phase extraction column, using N-methylimidazole + acetonitrile(1+1，V/V) and trifiuoroacetic anhydride + acetonitrile(1+2，V/V) as the derivatization reagents. The mobile phase was acetonitrile and water(90+10，V/V) with equivalent elution，quantified by HPLC-FLD. The validation results showed that the limit of detection (LOD) of the method was 2 μg/kg, and the limit of quantification (LOQ) was 5 μg/kg in milk. Meanwhile, at the concentrations of 5，20，40 and 80 μg/kg in moxidectin spiked blank milk， the average recoveries of this method were 75.5%～110%, with the intra-day coefficient variation (CVd) were less than 7.38%, inter-day coefficient variation (CVr) were less than 7.87%; the recoveries ranged from 77.5% to 95.6%, with the CVd were less than 5.06%, CVr were less than 5.92%. All of the above results show that this HPLC method has well practicability and accuracy， whitch could be applied in the rapid determination of moxidectin in milk.