Rapid screening assay for beta-lactam antibiotics in milk: collaborative study.
A 15 min assay for beta-lactam antibiotics has been used by dairies for several years as a screening procedure for testing milk tankers before they unload. The test is based on a competition between 14C-penicillin and beta-lactam antibiotics in the milk samples for sites on a microbial cell wall that specifically binds beta-lactam. In a collaborative study, 11 laboratories correctly distinguished 10 coded zero penicillin G samples and 10 coded 0.01 IU/mL samples. The proposed test is qualitative, positive or negative, and can detect the presence of beta-lactam antibiotics at the 0.01 IU/mL level. The control point for determining positive or negative samples is more than 3 standard deviations from the mean of 0.01 IU/mL. The method has been adopted official first action.
D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D001681:Biological Assay / Q000379:methods; D002417:Cattle; D001411:Geobacillus stearothermophilus; D008892:Milk / Q000032:analysis*; D010400:Penicillin G / Q000032:analysis
D000900:Anti-Bacterial Agents; D010400:Penicillin G