ENZYME-IMMUNOASSAY FOR THE DETECTION OF TRIMETHOPRIM IN RAW-MILK

Trimethoprim (TMP) is mostly used in combination with different sulfon amides for the treatment of bacterial infections. In milk a maximum re sidue limit (MRL) for TMP is fixed at 50 mu g/kg. An ELISA was develop ed for the determination of TMP in raw milk. Antibodies with a high sp ecificity were raised in rabbits. The ELISA was carried out as an indi rect competitive antibody-capture test with a detection limit of 12.5 mu g/kg. Quantification is possible up to 100 mu g/kg without sample d ilution. The immunoassay described is suitable as a screening method f or the detection of TMP at the MRL and fulfils the requirements of the EU-Regulation 281/96.