Biorecognition elements appended gold nanoparticle biosensors for the detection of food-borne pathogens - A review

Food-borne diseases emanated from bacterial contamination pose serious threats to human food safety and well-being. Microbes such as Clostridium perfringens, Escherichia coli (E. coli), Listeria monocytogenes (L. monocytogenes), Norovirus, Pseudomonas aeruginosa (P. aeruginosa), Salmonella ssp, Shigella ssp, Staphylococcus aureus (S. aureus), are key food-borne pathogens, hazardous to human health. Conventional methods undertaken for the detection of the microbes include colorimetry, electrochemical analysis, surface-enhanced Raman spectroscopy (SERS), fluorescent spectroscopy, and lateral flow assay. The pathogen discovery methods employ gold nanoparticles (Au-NPs), upheld by their specific optical properties, conductivity, biocompatibility, and high surface area-to-volume ratio. Au-NPs double up as colorimetric nanoparticles, enzyme mimics, fluorescence resonance energy transfer (FRET) quenchers and signal enhancers. In conjugation with biomolecules like nucleic acids, aptamers, antibodies, cells and phages, Au-NPs can discretely discern and bind to target pathogens. This treatise presents a comprehensive review of recent (2015–2021) developments on biorecognition elements appended to Au-NPs, and their deployment in identification of food-borne microorganisms.