二氟沙星残留检测直接竞争ELISA试剂盒的研制及其性能测定

应用抗二氟沙星单克隆抗体（DIFmAb）杂交瘤细胞株建立直接竞争ELISA分析方法，研制出DIF残留快速检测试剂盒（DIF-Kit）并对其性能进行了测定。特异性试验结果表明与达氟沙星的交叉反应率为0.32％，与其它氟喹诺酮类药物和磺胺类药物无交叉反应，该方法对DIF的检测限可达到0.1µg/L,半数抑制浓度IC50为2.2µg/L，线性范围0.1～128µg/L， 平均批内和批间变异系数小于<15%。对牛奶、鸡肉分别添加0.4、2.0、10.0、50.0µg/LDIF标准品，平均回收率分别为89.3%和83.9%。DIF-Kit性能稳定，在4℃可保存6个月。DIF-Kit准确度高、重复性好、特异性强，适用于DIF残留快速检测的推广应用。

Development and Trait Identification of Direct Competitive ELISA Kit for Difloxacin Residues

A Competitive ELISA kit for detection of Difloxacin（DIF-Kit）was developed with generating hybridoma lines that secrete DIFmonoclonal antibodies（DIF mAb）and the method of ciELISA,its traits were identified. The DIF-Kit had 0.24% cross-reactivity towards Danofloxacin,and little or no cross-reactivity towards other FQNS and sulfamido.The detection limit for DIF was 0.1µg/L and IC50 was 2.2µg/L.The The precision and accuracy of the assay as determined by inter-assay and intra-assay coefficient variation were below 15% in range of 0.1～128.0µg/L. The recoveries from milk and chicken were 89.3% and 83.9%,respectively,when 0.4、2.0、10.0、50.0.0µg/L DIF were spiked. The validity of DIF-Kit in 4℃ was above six months.The DIF-Kit possesses high accuracy, good reproducibility,specificity.That is proved to be used for the rapid detection of DIF residues in animal food.