Validation of the SL3 beta-Lactam Test for screening milk in compliance with U.S. pasteurized milk ordinance: performance tested method 040701.
The SL3 beta-Lactam Test is a 3 min, receptor-based lateral flow Rapid One Step Assay (ROSA) that detects 5 of 6 beta-lactam drugs approved for dairy cattle in the United States. The method was evaluated through the AOAC Research Institute Performance-Tested Method program following a U.S. Food and Drug Administration protocol. Three combined lots detected penicillin G 4.2 parts per billion (ppb), ampicillin 8.7 ppb, amoxicillin 7.8 ppb, cephapirin 16.0 ppb, and ceftiofur (total metabolites) 51 ppb at least 90% of the time, with 95% confidence as determined by dose response probit analysis. These detection levels are less than safe level/tolerances but not more than 50% less. Lot repeatability was within 20%. Incurred residues were detected comparably or more sensitively to fortified samples due to the cumulative effect of biologically active metabolites. There were no interferences from somatic cells at 1 M/mL, bacterial cells 500 000 colony-forming units/mL, or 30 other non-beta-lactam drugs. These performances met approval conditions of the National Conference on Interstate Milk Shipments. Ruggedness conditions were incorporated into public health procedures for annual laboratory proficiency and certification.
Salter
Robert S
RS
Charm Sciences Inc., 659 Andover St, Lawrence, MA 01843, USA.
Conaway
David
D
Markovsky
Robert
R
D000658:Amoxicillin / Q000032:analysis / Q000592:standards; D000667:Ampicillin / Q000032:analysis / Q000592:standards; D000818:Animals; D002511:Cephalosporins / Q000032:analysis / Q000592:standards; D002514:Cephapirin / Q000032:analysis / Q000592:standards; D005504:Food Analysis / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D005506:Food Contamination / Q000032:analysis*; D008892:Milk / Q000737:chemistry* / Q000592:standards*; D010400:Penicillin G / Q000032:analysis / Q000592:standards; D011786:Quality Control; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013242:Sterilization; D014481:United States; D019155:Veterinary Drugs / Q000032:analysis / Q000592:standards; D047090:beta-Lactams / Q000032:analysis* / Q000592:standards
D002511:Cephalosporins; D019155:Veterinary Drugs; D047090:beta-Lactams; D000667:Ampicillin; D000658:Amoxicillin; C053503:ceftiofur; D002514:Cephapirin; D010400:Penicillin G