Immunological Methods For The Determination Of Enrofloxacin Residues In Food Produces

In this paper, the immunosorbent assay method for the determination of Enrofloxacin (ENF) residues in the animal derived foods had been developed. We investigated the method of coupling the hapten to carrier albumens. The anti- ENF antibody produced was specific for ENF.A competitive direct enzyme-linked immunosorbent assay (cdELISA) for the rapid detection of ENF in various food matrices was developed. The sensitivity of the method was higher. In the cdELISA, the limit of detection for determination of ENF residues in different matrix was 0.02±0.01μg/kg , the IC₅₀ was 0.35±0.05μg/kg. After liquid extraction from pork, shrimp, Chicken , beef, milk and codfish samples with 2.5 times solution of acetonitrile and sodium hydroxide(80:20), sample extracts diluted with buffer were analyzed by direct competitive enzyme-linked immunosorbent assay directly. A simple, rapid and efficient extraction method was developed and 76%-109% recoveries of samples were obtained. In order to validate cdELISA, samples were analyzed by high-performance liquid chromatography. The correlation between data which was obtained by using microwell assay and the one attained by HPLC was good (the R² value was 0.96).An enzyme-linked immunosorbent assay (ELISA) based on polyclonal antibody with enhanced chemiluminescent (ECL) detection ENF in food samples has been developed. Assay conditions were optimized, and IC₅₀ value of the optimized ECL-ELISA system was 0. 07±0. 015μg/kg, and a limit of detection of the assays was 0. 008±0.002μg/kg. An efficient extraction method was developed and 63%-89% recoveries of samples were obtained. The ECL-ELISA was about3-4 times more sensitive and about 20% time less than that of cdELISA by using the same antibody and HRP-conjugate.The results correlated well with those obtained by using conventional direct competition ELISA and HPLC method, which indicated that ECL-ELISA was capable of being applied for the specific detection and routine monitoring of ENF in food samples.The ELISA method and the rapid extraction method developed in this paper is feasible for preparing ELISA kits, which can determine ENF residues in animal derived foods rapidly.