From hidden danger to rapid detection: silver-enhanced urchin-like tungsten oxide MEMS sensors for Listeria monocytogenes detection in refrigerated dairy.

Listeria monocytogenes (LM), a foodborne pathogen renowned for its cold tolerance, often poses a contamination threat to dairy products, underscoring the urgent need for rapid detection methods to prevent outbreaks. Herein, urchin-like WO3 nanostructures modified with Ag nanoparticles are employed to construct a highly active surface, which exhibits excellent sensing performance for 3-hydroxy-2-butanone (3H2B), a characteristic biomarker of LM. The 1.0 wt% Ag-WO3-based sensor characterized by high sensitivity (Ra/Rg = 92.7@30 ppm 3H2B), satisfactory repeatability, and potential for practical applications. Furthermore, confirmed that the chemical sensitization effect of Ag nanoparticles significantly reduces reaction activation energy. The developed gas sensor achieves highly accurate detection of LM at trace concentrations in dairy products. These insights could pave the way for the development of more efficient food safety diagnostics, ultimately contributing to enhanced public health protection.