Enzyme immunoassay for staphylococcal enterotoxin A.

An enzyme immunoassay procedure specifying alkaline phosphatase-labeled enterotoxin A was used to determined enterotoxin in standardized solutions and food extracts. Staphylococcus aureus Cowan 1 cells were used to separate unbound from antibody-bound enterotoxin. The method is sensitive to 2 ng enterotoxin A/mL; cross reactions with other staphylococcal enterotoxins did not interfere with the specificity. The method is sensitive and precise enough to serve as a reliable alternative to radioimmunoassay for enterotoxin A.