Detection of Salmonella typhimurium in food matrices by an amperometric immunosensor with Pequi carbon dot- labeled antibody

Abstract The sandwich amperometric immunosensor based on pequi- derived carbon dots (CDs) for labeling second antibody represents a promising approach for a rapid and quantitative detection of Salmonella sp. in liquid (water used for washing chicken- CWW) and solid (cheese- CC1) samples. The original microbiota of each sample was preserved, and each one was intentionally contaminated with Salmonella enterica serovar Typhimurium. The immunosensor was tested in the presence of Escherichia coli and Staphylococcus aureus , it exhibited specificity and effectively detected Salmonella with a low limit of detection (LOD) which was 0.8 CFU/mL and 0.1 CFU/mL for CWW and CC1, respectively. The electrochemical measurement time was two minutes without pre-enrichment step of the pathogen and the total assay time was about two hours. This study demonstrates the potential of this immunosensor for a rapid and sensitive Salmonella detection in real samples.