Monoclonal antibody-based ELISA for the quantification of nitrofuran metabolite 3-amino-2-oxazolidinone in tissues using a simplified sample preparation

摘要

A sensitive and specific monoclonal ELISA for the determination of tissue bound furazolidone metabolite 3-amino-2-oxazolidinone(AOZ)is described.The procedure enables the detection of AOZ in matrix supernatant after homogenisation,protease treatment,acid hydrolysis and derivatisation of AOZ released from the tissue by omicro-nitrobenzaldehyde.The formed p-nitrophenyl 3-amino-2-oxazolidinone(NPAOZ)is determined by ELISA calibrated with matrix-matched standards in the concentration range of 0.05-5.0 mugI~(-1).The assay was validated according to criteria set down by Commission Decision 2002/657/EC for the performance and validation of analytical methods for chemical residues.Detection capability,set on the basis of acceptance of no false negative results,was 0.4 mug kg~(-1)for shrimp,poultry,beef and pork muscle.This sensitivity approaches the established confirmatory LC-MS/MS able to quantify tissue-bound AOZ at levels as low as 0.3 mug kg~(-1).An excellent correlation of results obtained by ELISA and LC/MS-MS within the concentration range 0-32.1 mug kg~(-1)was found in the naturally contaminated shrimp samples(r=0.999,n = 8).A similar correlation was found for the incurred poultry samples within the concentration range of 0-10.5(mug kg~(-1)(r=0.99,n = 8).