Nanoparticles promise rapid Vibrio control for safer seafood and healthier fish

Vibrio bacteria are major pathogens in the aquaculture industry, triggering vibriosis, a disease that can cause mortality rates of up to 90% within two days. This not only causes billions of dollars in economic losses globally, but also poses a threat to food security due to contamination of aquatic products. Conventional methods of detecting Vibrio require three to five days to yield results, and they often involve additional sterilization steps, making it almost impossible to quickly control the spread of Vibrio infections.

To address this challenge, a research team led by Professor Chen Lingxin from the Yantai Institute of Coastal Area Research of the Chinese Academy of Sciences developed satellite-based AuAg nanoparticles (ES-AuAgNPs). These nanoparticles (NPs) exhibit several characteristics, including Ag/Au alloy composition, satellite-like structural design, and integrated antimicrobial components.

Collectively, these properties endow ES-AuAgNPs with enhanced peroxidase-like (POD) catalytic activity, surface-enhanced Raman scattering (SERS) performance, and antibacterial capabilities. This study was recently published in Advanced science.

By taking advantage of the triple performance of ES-AuAgNPs and integrating a specific modified aptamer probe, the research team designed a portable, modular and centimeter-sized platform. This platform is capable of simultaneously screening, validating and eliminating three pandemic species of marine Vibrio: Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio alginolyticus.

The platform operates via a coordinated, multi-step mechanism. First, its POD-like catalytic colorimetric capability allows rapid screening for the presence of these Vibrio bacteria via a visible color change, allowing on-site personnel to quickly identify potential infection risks. Second, the SERS-based detection function validates the identity of detected bacteria with multiplexing capability. Meanwhile, the inherent antibacterial properties of ES-AuAgNPs ensure that once bacteria are detected and identified, they can be effectively eliminated.

The platform demonstrated notable performance in rapid screening (2 minutes), sensitive validation (limit of detection, ~50 CFU/mL), and effective antimicrobility (45 min, 100%). This integrated platform, built around ES-AuAgNPs, is expected to greatly improve aquaculture management practices by enabling seamless analysis and removal of Vibrio bacteria.