Establishment of a heterologous immunoassay for detecting enrofloxacin residues in poultry muscles

Abstract

A heterologous indirect competitive enzyme linked immuno sorbent assay (icELISA) has been developed for
the determination of enrofloxacin (ENR) residues in poultry. For this purpose, carbodiimide active ester
method was employed to synthesize the artificial antigen of ENR- bovine serum albumin (BSA) while mixedanhydride technique was used to synthesize the coating antigen of ENR- ovalbumin (OVA), to pursue the
heterologous sensitivity. By square matrix titration, an icELISA method was developed, and the linear range
was from 0.02 to 86.3 ng/mL, with limit of detection (LOD) and IC50 value of 0.8 and 0.01 ng/mL, respectively.
After optimization, 5% of NaOH was used in the assay buffer and this ELISA system can tolerate methanol not
higher than 30%. The correlation coefficients (R2
) between concentration spiked and concentration
determined were 0.9975 in chicken muscle and 0.9959 in duck muscle, respectively. Therefore, this assay has
the potential to be incorporated into a quantitative monitoring program for the rapid screening of ENR residue
in poultry muscles.