Probe-free nanosensor for the detection of Salmonella using gold nanorods as an electroactive modulator

Salmonellosis is a symptomatic infection, a foodborne disease, caused by Salmonella that enters the body through the ingestion of contaminated food. In this study, a novel electrochemical biosensor integrated with gold nanorods (GNRs) was used to explore the interaction between in-house generated antibodies with Salmonella serovars. Under optimal conditions, the proposed immunosensor depicted a linear range of detection (1-1 × 10⁵) CFU/mL witha detection limit of 105 and 23 colony forming units (CFU) ofS. entandS. typhirespectively. The designed GNR/S. ent/S. typhi/Ab immunosensor was able to successfully detectS. ent/S. typhiin spiked meat and milk samples respectively, with a long shelf life, good repeatability, as well as reproducibility under optimised conditions. Along with the ease of fabrication, the developed electrode produced a highly specific response, and displayed negligible cross reactivity with other Salmonella species. Moreover, the established detection technique may be used as an alternative to conventional analytical approaches for rapid and sensitivediagnosis of Salmonellosis.