Immunomagnetic separation-based nanogold enhanced surface plasmon resonance and colloidal gold test strips for rapid detection of Vibrio parahaemolyticus.

Nanogold enhanced surface plasmon resonance (SPR), colloidal gold immunochromatographic test strips (ICTS), and polymerase chain reaction (PCR), combined with immunomagnetic separation (IMS) were established in this study for the rapid detection of Vibrio parahaemolyticus (VP). The sensitivities of SPR, ICTS, and PCR was determined to be 101, 103, and 103 CFU/mL for VP, respectively. After separation and enrichment by IMS, the sensitivities of SPR, ICTS, and PCR were 100, 101, and 102 CFU/mL for VP, respectively, which were improved by 10-, 100-, and 10-fold compared to the direct detection by SPR, ICTS, and PCR, respectively. When the VP-polluted water samples were directly assessed by SPR, ICTS, and PCR, the results were negative. By contrast, after separation and enrichment for 45 min by IMS, the results were all positive. The IMS-SPR, IMS-ICTS, and IMS-PCR detection methods were able to yield results in approximately 1.5 h, 55 min, and 3.5 h, respectively. These combined detection methods have advantages in being high-throughput and easy to operate without the need for sophisticated equipment or specialized skills. These methods might aid in the development of SPR, ICTS, and PCR technologies for simultaneously examining multiple food-borne pathogens in food products.