A sensitive multimode dot-filtration strip for the detection of Salmonella typhimurium using MoS₂@Fe₃O₄

A sensitive, accurate, and rapid multimode dot-filtration immunoassay (MDFIA) was established for the detection of Salmonella typhimurium using the intrinsic color, catalytic property, and photothermal effect of magnetic molybdenum disulphide (MoS₂@Fe₃O₄). The critical performance parameters of MDFIA were optimized in detail. The sensitivity of MDFIA can be improved by the catalytic color development and photothermal conversion of MoS₂@Fe₃O₄ with a limit of detection (LOD) of 10¹ CFU·mL^-1, which is an order of magnitude lower than direct visual detection (10² CFU·mL^-1). Besides, the magnetic property of MoS₂@Fe₃O₄ was used for the rapid enrichment and separation of the target allowing detection of trace concentrations of Salmonella typhimurium. The selectivity and applicability of the MDFIA were verified in spiked samples, indicating that the established assay may have bright application prospects for the detection and control of foodborne pathogens. A multimode dot-filtration immunoassay was constructed for Salmonella typhimurium rapid detection based on the peroxidase-like activity, magnetic property, and photothermal effect of MoS₂@Fe₃O₄.