DNA array with the groESL intergenic sequence to detect Vibrio parahaemolyticus and Vibrio vulnificus

Giant Gold Nanowire Vesicle-Based Colorimetric and SERS Dual-Mode Immunosensor for Ultrasensitive Detection of Vibrio parahemolyticus

Conventional methods for the detection of Vibrio parahemolyticus (VP) usually need tedious, labor-intensive processes, and have low sensitivity, which further limits their practical applications. Herein, we developed a simple and efficient colorimetry and surface-enhanced Raman scattering (SERS) dual-mode immunosensor for sensitive detection of VP, by employing giant Au vesicles with anchored tiny gold nanowires (AuNW) as a smart probe. Due to the larger specific surface and special hollow structure of giant Au vesicles, silver staining would easily lead to vivid color change for colorimetric analysis and further amplify SERS signals. The t-test was further used to determine if two sets of data from colorimetry and SERS were significantly different from each other. The result shows that there was no significant difference between data from the two methods. Two sets of data can mutually validate each other and avoid false positive and negative detection. The designed colorimetry-SERS dual-mode sensor would be very promising in various applications such as food safety inspection, personal healthcare, and on-site environmental monitoring.

Development of a groEL gene-based species-specific multiplex polymerase chain reaction assay for simultaneous detection of Vibrio cholerae, Vibrio parahaemolyticus and Vibrio vulnificus

AIMS

To develop an effective multiplex polymerase chain reaction (PCR) for the simultaneous detection of three important Vibrio species, Vibrio cholerae (Vc), V. parahaemolyticus (Vp) and V. vulnificus (Vv) using the groEL gene, a potential phylogenetic marker.

METHODS AND RESULTS

Three species-specific primer sets were designed to target Vc, Vp and Vv. A total of 131 Vibrio and non-Vibrio strains were used to determine the specificity and sensitivity of primers. The primers produced specific PCR fragments from all target species strains and did not cross-react with other Vibrio and non-Vibrio species. This PCR method showed good efficiency in detecting coexisting target species in the same sample with a detection limit of 100 pg of Vc, Vp and Vv from mixed purified DNA. Detection of three target species was also possible from artificially inoculated shellfish, flounder and sea water.

CONCLUSIONS

The groEL gene is a potential marker for accurate simultaneous detection of Vc, Vp and Vv and could be used to detect these species in environmental and clinical samples.

SIGNIFICANCE AND IMPACT OF THE STUDY

This newly developed multiplex PCR is a useful and cost-effective method that is applicable in a disease-outbreak prediction system and may provide an effective tool for both the epidemiologist and ecologist.