草鱼组织中阿维菌素和伊维菌素的多残留检测

建立了草鱼肌肉（包括皮）中阿维菌素和伊维菌素的多残留检测方法。样品用乙腈提取,正己烷脱脂净化,多拉菌素作内标,经1-甲基咪唑和三氟乙酸酐的乙腈溶液在室温下避光衍生化并在甲醇中水解后,进行HPLC-FLD检测分析。结果表明,阿维菌素和伊维菌素在5~100 ng/g范围内具有良好线性,检测限分别为1.0 ng/g和1.2 ng/g,定量限分别为3.4 ng/g和4.0 ng/g,日间提取回收率分别为96.42%~103.10%和94.23%~101.76%,日内和日间变异系数分别小于4.37%、6.82%和6.73%、8.84%。该方法高效、灵敏、简便,其灵敏度、回收率和重现性等符合有关兽药残留检测要求,可用于草鱼肌肉中阿维菌素和伊维菌素的多残留检测。

The Multi-residue Determination of Avermectin and Ivermectin in Grass carp muscle tissues

A multi -residue method was developed and validated for the simultaneous quantitation and confirma- tion of marker residues avermectin B1a and ivermectin H2B1a in grass carp muscle adhering skin tissue by use of high- performance liquid chromatography with fluorescent detection （HPLC -FLD）. Samples were extracted by aeetonitrile, the grass carp muscle homogenate degreased by n - hexane, derivated by 1 - methylimidazole and trifluoroacetic anhydride in acetonitrile and hydrolyzed in methanol in dark at room temperature subsequently. The doramectin was used as internal standard. HPLC - FLD results showed that the calibration curves were linear within the working range from 5 to 100 ng/g for the two drugs. For the quantitative analysis, the limit of detection of the method for avermectin and ivermectin was 1.0 ng,/g and 1.2 ng/g, while the limit of quantitation for avermectin and ivermectin was 3.4 ng/g and 4.0 ng/g respectively. The overall recoveries of avermectin and ivermectin in the grass carp tissue ranged from 96.42% to 103.10% and 94.23% to 101.76%. The intra - day and inter -day coefficient variations were less than 4.37% ,6.82% and 6.73% ,8.84% respectively. The results showed that the method was effective, sensitive, simple, convenient and precise for the multi - residue determina- tion of avermectin B1a and ivermectin H2B1a in grass carp muscle tissues.