Joint concanavalin A-aptamer enabled dual recognition for anti-interference visual detection of Salmonella typhimurium in complex food matrices.

Given that food poisoning and infectious diseases caused by Salmonella typhimurium (S. typhimurium) draw intensive public health concerns, developing rapid, accurate, and cost-effective approaches to detect the pathogen is of crucial importance. Herein, we proposed a concanavalin A (Con A)-aptamer joint strategy to realize dual recognition for the strongly specific, visual, and highly sensitive determination of S. typhimurium. Compared with currently used single identification strategies, Con A and aptamer could recognize different sites of S. typhimurium to enhance the utilization rate of these sites for better sensing. The developed assay offered specific detection of S. typhimurium against other bacteria in a remarkably wide concentration range of 7.0 × 101 ∼ 7.0 × 109 CFU/mL, along with a detection limit as low as 23 CFU/mL. Real sample analyses of milk and pork demonstrated the excellent reliability and practicability of our assay, providing great potential for food safety analysis.