Improvement of colloidal gold based immunochromatographic strip test for detection of Vibrio parahaemolyticus

To establish a rapid, specificity and sensitivity strip test for detection of Vibrio parahaemolyticus (VP) . Gold nanoparticles were coupled with monoclonal antibodies of VP, polyclonal antibodies against VP and Donkey anti-mouse IgG were separately coated on nitrocellulose membrane as test line and control line to detect the limit of detection and specifity. Results showed that color intensity increased by 5 times after adding the colloidal gold-labeled goat anti-mouse secondary antibody, was conducive to the naked eye observation. The detection sensitivity of the test was 106CFU/mL in pure culture and 107CFU/mL in fish paste samples (in the presence of other kinds of bacteria species) . The strip had no cross-reaction with other bacterial strains, showing high specificity to VP. With a high specificity and sensitivity, the modified strip test is applicable in the detection of VP.