饲料中莫昔克丁的含量测定

Content Determination of Moxidectin in Feed

[目的]采用二极管阵列高效液相色谱法,建立饲料中莫昔克丁的检测方法。[方法]样品经乙腈溶液提取后,通过HLB 6cc SPE固相萃取小柱净化,C_(18)色谱柱分离;以醋酸-醋酸铵缓冲液(pH 4.8)(取醋酸铵7.7 g,加水400 mL溶解后,用冰醋酸调节pH至4.8)-乙腈(400∶600)为流动相;检测波长为242 nm;柱温50℃;流速为2.5 mL/min。[结果]莫昔克丁在5~100μg/mL具有良好的线性关系(R^(2)=0.9990)。检出限为0.5 mg/kg,定量限为1.0 mg/kg。样品在定量限1倍、2倍、10倍3个加标水平下的平均回收率为95.0%~105.2%,批内、批间的相对标准偏差小于10%,日间和日内变异系数均低于15%。[结论]该试验建立的HPLC法简便、灵敏、准确,可用于饲料中莫昔克丁的含量测定。

[Objective]A method for the determination of moxidectin feed by diode array high performance liquid chromatography(DAD-HPLC)was established.[Method]The sample was extracted by acetonitrile solution and purified by HLB 6cc SPE SPE solid phase extraction column.The mobile phase was acetic acid-ammonium acetate buffer(pH 4.8)(7.7 g ammonium acetate was dissolved in 400 mL water,and pH was adjusted to 4.8 with glacial acetic acid)-acetonitrile(400∶600)as the mobile phase;the detection wavelength was 242 nm;the column temperature was 50℃;the flow rate was 2.5 mL/min.[Result]There was a good linear relationship in the range of 5-100μg/mL(R^(2)=0.9990).The detection limit was 0.5 mg/kg and the limit of quantitation was 1.0 mg/kg.The average recoveries of the samples were 95.0%-105.2%at 1,2 and 10 times of the limit of quantification(LOQ).The intra and inter assay relative deviations were less than 10%,and the inter-day and intra-day coefficients of variation were less than 15%.[Conclusion]The HPLC method established in this experiment is simple,sensitive and accurate,and can be used to determine the content of moxidectin in feed.