Improved radioimmunoassay of Staphylococcal enterotoxin a.

A simple solid-phase radioimmunoassay was developed for detecting staphylococcal enterotoxin A (SEA) in food. The method detected 85-100% SEA added to extracts of 6 kinds of foods, and 52-100% SEA added directly to foods at a concentration of 1 ng/g. Assay sensitivity is about 0.3 ng toxin/mL extract. The method is specific for SEA; results are only marginally affected by staphylococcal enterotoxins B and C2 present at concentrations as high as 500 ng/mL extract.