Validation study of the BetaStarReg. plus lateral flow assay for detection of beta-lactam antibiotics in milk.

摘要

A validation study designed to meet the requirements of the AOAC Research Institute and the US FDA, Center for Veterinary Medicine (FDA/CVM) was conducted for a receptor and antibody-based, immunochromatographic method (BetaStarReg. Plus) for detection of beta-lactam antibiotic residues in raw, commingled bovine milk. The assay was found to detect amoxicillin, ampicillin, ceftiofur, cephapirin, cloxacillin and penicillin G at levels below the FDA tolerance/safe levels, but above the max. sensitivity thresholds established by the National Conference on Interstate Milk Shipments (NCIMS). Results of the Part I (internal) and Part II (independent laboratory) dose-response studies employing spiked samples were in close agreement. The test was able to detect all 6 drugs at approx. 90/95% sensitivity levels when presented as incurred residues in milk collected from cows that had been treated with the specific drug. Selectivity of the assay was 100%, as no false-positive results were obtained in testing of 1031 control milk samples. Results of ruggedness experiments established the operating parameter tolerances for the BetaStar Plus assay. Results of cross-reactivity testing established that the assay detects certain other beta-lactam drugs (dicloxacillin and ticarcillin), but it does not cross-react with any of 30 drugs belonging to other classes. Abnormally high bacterial or somatic cell counts in raw milk produced no interference with the ability of the test to detect beta-lactams at tolerance/safe levels.