Study on detecting enrofloxacin residues in food by chemiluminescence immunoassay

It was developed a chemiluminescence immunoassay(CLIA) method based on polyclonal antibody to detect the enrofloxacin residue in animal food. The CLEIA conditions were optimized. The optimal concentration of coating antibody dilution was 1∶64000 and the enrofloxacin markered enzymes dilution was 1∶256000. The results showed that:with an concentration range from 3 to 810pg/mL,the regression equation was y=-13.898x+ 110.38(R2=0.9893). The 50% inhibition percentage(IC50) and sensitivity(IC10) was 69.63pg/mL and 1.41pg/mL, respectively. Actual sample testing experiment results showed:in chicken,fish,shrimp,honey and milk samples, the detection limits was 3.76,4.59,2.85,2.65 and 4.20pg/mL,respectively. The limit of quantity was 6.13,7.35, 3.57,3.73 and 6.48pg/mL,respectively. Recoveries were between 88.28% ~102.6% when ENR was spiked to samples at 50~1000pg/g(pg/mL). The mean intra-assay variability and inter-assay was 2.61% and 4.71%, respectively. The CLIA which we stablished could be used to detect enrofloxacin residues in animal food.