Anti-AOZ polyclonal antibody

Several new haptens for furazolidone metabolites 3-amino-2-oxazolidnone (AOZ) were synthesized and coupled to bovine serum albumin (BSA) as immunogen and used to immunize Balb/c mice. A cell strain secreting anti-AOZ monoclonal antibody from hapten H-3 was obtained by cell fusion and screening. The titer of antibod was 1:2000000, the subtype was IgG1 and the affinity constant was equal to 6.68x10(10) L/mol. The monoclonal antibody obtained was highly specific to AOZ. Furthermore, based on investigating the effect of homology and heterologous coating antigens with different structures on the ELISA sensitivity, indirect competitive ELISA (icELISA) and direct competitive ELISA (dcELISA) test methods could be established with H-5-OVA as the best heterologous coating antigen. The IC50, limit of detection and linear range for AOZ were 1.189 mu g/L, 0.056 mu g/L and 0.14-23.6 mu g/L for icELISA and 0.503 mu g/L, 0.017 mu g/L and 0.06-14.0 mu g/L for dcELISA, respectively. Both formats of ELISA can achieve related requirement of maximum residue limits (MRLs) for AOZ and provide a potential and alternative rapid immunoassay method to detect AOZ in food.

Residues of furazolidone in pig tissues have previously been shown to be bioavailable in the rat. However, no specific furazolidone metabolite has been identified in the tissues of a second species. Tissues were taken from pigs that had been treated therapeutically with furazolidone, lyophilized and then fed to female Sprague Dawley rats for 3 days. Protein-bound and solvent-extractable residues containing the side chain metabolite 3-amino-2-oxazolidinone (AOZ) were detected in the liver, kidney and muscle of the rats using HPLC-thermospray mass spectrometry. Furazolidone-contaminated pig tissues which had undergone solvent extraction and thereby contained only bound residues, was fed to two rats. Bound and extractable AOZ was detected in liver, kidney and muscle. Since it is most likely that consumers would eat animal tissue which had been cooked, an experiment was carried out to determine the effects of cooking upon the concentrations of AOZ residues in pig tissues. Total AOZ concentrations were not significantly reduced in liver, kidney or muscle, following frying, grilling or microwaving.