EVALUATION OF COMMERCIALLY AVAILABLE ELISA TEST KITS FOR THE DETECTION OF CLENBUTEROL AND OTHER BETA-2-AGONISTS

This article presents the results of a comparative study of nine comme rcially available ELISA test kits for clenbuterol and other beta 2-ago nists currently being used in veterinary drug residue control of live and slaughtered animals in the European Union (EU). By determining mea suring ranges, B/B-0-50% values, inter- and intra-assay variations and cross-reactions as well as limits of detection (LOD) and recoveries f or clenbuterol in bovine urine it could be demonstrated that a number of test kits showed considerable quality defects, reducing their appli cability to residue control. LODs for urine assayed without a previous clean-up (as recommended by all kit manufacturers) varied between 1.2 and 11.1 ng clenbuterol per mi urine and did thus not meet the requir ement of 1 ng/ml of the official residue control plans of the EU Membe r States.