POLYMACRON ENZYME-IMMUNOASSAY SYSTEM FOR DETECTION OF NATURALLY CONTAMINATING SALMONELLA IN FOODS, FEEDS, AND ENVIRONMENTAL-SAMPLES

A simple dot blot enzyme immunoassay was developed to screen enrichmen t broth cultures for the presence of Salmonella. This unique system ut ilizes macroporous polyester cloth (Polymacron) with an inexpensive he moglobin coating to provide a high-affinity adsorbent for lipopolysacc haride (LPS) antigens in test samples. Bound LPS antigens are then det ected using a monoclonal antibody conjugate recognizing a core oligosa ccharide epitope common to all salmonellae frequently found in foods a nd related samples. The entire test (not including enrichment culture) could be completed in less than 1 h. The performance of this assay wa s evaluated in the analysis of enrichment broth cultures from a variet y of egg and dairy products, chicken carcasses, animal feeds, and food -processing plant environmental samples for the presence of Salmonella .