Immunodetection sensing platform for salmonella based on carbon nanotube amplification

A novel immunodetection sensing platform for Salmonella based on a CoFe-MOF-carbon nanotube composite was developed. The CoFe-MOF-CNT composite exhibited excellent electrochemical performance, providing a highly conductive and stable matrix for antibody immobilization and signal amplification. Under optimized conditions, the immunosensor demonstrated a wide linear range of 10 2 to 10 7  CFU/mL, with a low detection limit of 37 CFU/mL and a high sensitivity of 6.061 µA/log(CFU/mL). The immunosensor showed excellent specificity towards Salmonella, with a relative response of 100% for Salmonella and less than 10% for non-target bacteria. The immunosensor exhibited good reproducibility (RSD of 4.2%) and stability, retaining 88.7% of its initial response after 30 days of storage at 4 °C. The practical applicability of the immunosensor was demonstrated by analyzing spiked milk samples, with recoveries ranging from 96.7% to 105.2% and RSD less than 6.5%.