Direct detection of 3-amino-5-methylmorpholino-2-oxazolidinone (AMOZ) in food samples without derivatisation step by a sensitive and specific monoclonal antibody based ELISA

AMOZ (3-amino-5-methylmorpholino-2-oxazolidinone) is the metabolite of furaltadone (FTD) which has been banned as a veterinary drug. In this study, three AMOZ derivatives (CPAMOZ) were synthesised and monoclonal antibody against o-nitrobenzaldehyde derivatived AMOZ (NPAMOZ) was produced. The IC50 value of the ELISA for NPAMOZ was 0.17 ng ml−1. The cross reactivity values of the assay with NPAMOZ, CPAMOZ, AMOZ and FTA were 100%, 61.7%, 14.8% and 10.4%, respectively. As no NPAMOZ or CPAMOZ exist if no derivitizing reagent added and FTA is quite unstable, therefore, 14.8% of cross reactivity with AMOZ makes the ELISA capable of directly detecting AMOZ without derivatisation. AMOZ spiked food samples were analysed by ELISA. Recoveries of 72.6–121.2% and intra-assay coefficients of variation of 6.1–17.7% were obtained. The proposed ELISA which also confirmed by HPLC with a good correlation provides an alternative sensitive and fast quantitative method for directly detecting AMOZ in food samples.