Development of enzyme-linked immunosorbent assay (ELISA) for the detection of neomycin residues in pig muscle, chicken muscle, egg, fish, milk and kidney

A colorimetric competitive direct enzyme-linked immunosorbent assay (ELISA) method was developed using polyclonal antibody to determine neomycin residues in food of animal origin. No cross-reactivity of the antibody was observed with other aminoglycosides. The limit of detection of the method was 0.1 μg/kg. A simple and efficient sample extraction method was established with recoveries of neomycin ranged from 75% to 105%. The detection limits were 5 μg/kg(l) in pig muscle, chicken muscle, fish and milk, 10 μg/kg in kidney and 20 μg/kg in egg, respectively. Chemiluminescence assay was developed for detecting neomycin residues in pig muscle and chicken muscle. The limit of detection of the method was 0.015 μg/kg, and the detection limits were 1.5 μg/kg in pig muscle and 6 μg/kg in chicken muscle. The ELISA tests were validated by HPLC, and the results showed a good correlation (r2) which was greater than 0.9.