To successfully establish an immunochromatography strip assay for rapid detection Vibrio parahaemolyticus in food, two kinds of specific antibodies were employed. In the strip test, polyclonal rabbit antibody (pAb) against V. parahaemolyticus was conjugated with 40 nm colloidal gold and used as analytical reagent. Goat anti-rabbit IgG and monoclonal mouse antibody (mAb) against V. parahaemolyticus were dispensed on a nitrocellulose membrane in two distinct sectors, the former as control and the latter for test. The strip assay revealed 100% specificity with 31 strains (two V. parahaemolyticus type strains; fifteen V. parahaemolyticus strains isolated from foods, four other species of Vibrio strains and ten non-Vibrio strains). The detection limit of immunochromatographic strip was 105 cfu/mL. Shelf life of the strip was over 90 days at 37C. The immunochromatographic strip is therefore successful in and suitable for fast detection of V. parahaemolyticus.
In this study, we developed a colloidal gold immunochromatography strip for the detection of V. parahaemolyticus. Immunochromatography strip test has advantages of being simple, rapid, free from contamination and low in price. It would allow detection of V. parahaemolyticus pure cultures within a short time (<15 min) and detection of V. parahaemolyticus in food within 11 h, which contained 10 h enrichment. Rapid detection and easy operation makes the strip suitable for on-site detection. There is therefore much high application value in food microorganism, and it is worth to be popularized.