HPLC法测定牙鲆肌肉中恩诺沙星及其代谢产物环丙沙星

Determination of enrofloxacin and ciprofloxacin residues in Paralichthys oliuaceus muscle with HPLC method

利用高效液相色谱-荧光检测器分析了牙鲆肌肉中恩诺沙星及其代谢产物环丙沙星的含量。样品前处理方法为:以磷酸盐缓冲液作为提取液,样品经均质、离心后,用正己烷除去脂肪,再用ODS(C18)固相萃取柱净化,洗脱液蒸发浓缩后,乙腈溶解残渣。其色谱条件为:色谱柱XDB-C18柱(250mm×4.6mm);流动相0.01mol/L四丁基溴化铵(pH3.0)∶乙腈=94∶6(v/v);流速1.5ml/min;进样量10μl;柱温40℃;荧光检测器激发波长280nm、发射波长450nm。结果表明,在牙鲆肌肉中添加50、100和200μg/kg3个水平的恩诺沙星和环丙沙星混合物标准后,其回收率均大于80%,相对标准偏差小于10%。恩诺沙星与环丙沙星检出限均为10μg/kg。

CT Enrofloxacin and ciprofloxacin residues in Paralichthys oliuaceus muscle were determined simultaneously with HPLC and fl uorescence detector. Phosphate buffer was used as extraction solution. After being homogenized and centrifuged, the sampling solution was treated with n-hexane to remove the fat, and then purified by ODS（C18） cartridges. The eluate was evaporated and the residue was dissolved by acetonitrile. The chromatogram condition was as follows： XDB-C18 column was 250 mm×4.6 mm, mobile phase was 0.01 mol/L, pH of tetrabutyl bromide amine was 3.0, acetonitrile was 94 ： 6（v/v）, flow velocity was 1.5 ml/min, injection volume was 10 ul, column temperature was 40 ℃, λex was 280 nm, and λem was 450 nm. The results indicated that the average recoveries were all higher than 80 %, relative standard deviation was lower than 10 %, and the detection limits of both residues were 10μg/kg, when Paralichthys oliuaceus muscle was injected with standard of enrofloxacin and ciprofloxacin mixture at 3 levels of 50 μg/kg, 100 μg/kg, and 200 μg/kg.