Ver-0157 Ag strip by DRG International Inc.

VER-O157 test is an immunochromatographic rapid assay for the qualitative detection of E.coli O157 and verotoxins 1and 2 (syn. shigatoxins) from a stool enrichment in mTSB broth.

VER-O157 test employs a combination of:

• Green latex-conjugated monoclonal antibody against E.coli O157 antigen, and a solid-phase specific E.coli O157 antibody
• Red latex-conjugated monoclonal antibodies against the verotoxins 1 and 2 antigens, and solid-phase specific verotoxins 1 and 2 antibodies
• Blue latex particles conjugated to an antigen recognised by an antibody specific for that antigen and bound to the membrane, serving as the control band test.

In this test the stool sample is first enriched in the selective mTSB broth (with Mitomycin C) during 18 - 24 hours at 37 °C to stimulate the growth of E.coli and the verotoxin production. After centrifugation of this culture, an aliquot of the supernatant is diluted to 50% in the dilution buffer of the test and the sample is ready for the measurement with the VER O157 test.As the sample flows through the test membrane, the coloured particles migrate. In the case of a positive result the specific antibodies present on the membrane will capture the coloured particles. Different coloured lines will be visible, depending upon the antigens content of the sample. These lines, after 15 minutes of incubation at room temperature, are used to interpret the result.