Microbiological Toxins techniques

Techniques such as radioimmunoassay (RIA), agglutination, and enzyme-linked immunosorbent assay (ELISA), require less concentration of the food extracts ; thus, they save time and are more sensitive. Latex agglutination (16) appears promising as a serological tool for identifying staphylococcal enterotoxins. Several ELISA methods (26,28,30,32,37,38,39) have been proposed for the identification of enterotoxins in foods, but, except for a polyvalent ELISA (7,9), their specificity has not been studied extensively.

Among ELISA methods, the "double antibody sandwich" ELISA is the method of choice, because reagents are commercially available in polyvalent and monovalent formats for both toxin screening and serotype specific identification(22). An automated enzyme-linked fluorescent immunoassay (ELFA) has been developed and is commercially available.

This method has undergone specificity and sensitivity evaluations and has proven to be an effective serological system for the identification of staphylococcal enterotoxin in a wide variety of foods (14). Other methods, which have been used in the identification of the staphylococcal enterotoxins and may have application in foods, are the T-cell proliferation assay (35), and polyacrylamide gel electrophoresis (PAGE) combined with Western blotting (2).


References
http://www.cfsan.fda.gov/~ebam/bam-13a.html