Nanozyme Enhanced Colorimetric Immunoassay for Naked-Eye Detection of Salmonella Enteritidis

Salmonella Enteritidis is a major public health threat of global proportions, while it is still a serious challenge to develop point-of-care detection assay. In this study, nanozymes (Fe-MOF nanoparticles) were successfully synthesized and applied as signal in a colorimetric immunoassay for naked-eye detection of Salmonella Enteritidis. After optimization, the proposed assay was able to detect Salmonella Enteritidis with a detection limit of 34 CFU/mL. The coefficients of variation (CV) of the test were less than 7.0% after 30days storage at 4 degrees C. The estimated recoveries in milk samples of the colorimetric immunoassay range from 94.68 to 124%, which indicated the developed method is capable of detecting Salmonella Enteritidis in real samples. This method provides a potential platform for Salmonella detection with naked eyes, which has a significant application value for foodborne pathogen analysis at the point-of-care.