Development of an indirect competitive chemiluminescence enzyme immunoassay kit for detecting of enrofloxacin residue

A HRP-Luminol-H2O2 system based indirect competitive chemiluminescence enzyme immunoassay (CLEIA) kit for determination of enrofloxacin (ENR) residues was developed.The CLEIA conditions were optimized.The optimal concentration of coating antigen was 0.5ng/mL and the antibody dilution was 1:2000.Using PBST as assay buffer, the incubation time for the primary antibody was 30min.Under the optimal conditions, the standard curve was developed.The regression equation for ENR was y=-22842x+172936 with a linear detection ranging from 0.024 to 2.76ng/mL.The IC50 was 0.106ng/mL.The averaged recoveries of ENR from spiked honey, milk, shrimp and fish samples were 96%～116%, 90%～97%, 92%～112%and 86%～112%, respectively.The coefficient of variation of intra-assay and inter-assay was less than 15%.The developed kit can be stored at 4℃ for 180 days.