Whole-Cell Molecularly Imprinted Fluorescent Photonic Microsphere Microarray for High-Throughput Detection of Foodborne Pathogens

Rapid, sensitive, high-throughput, and cost-effective detection of multiplex foodborne pathogens is still challenging in public health. We designed a whole-cell imprinted microarray platform based on the surface of three-dimensional photonic microspheres for multiplex foodborne pathogenic bacteria using 3-formylphenylboric acid-functionalized silane as the functional monomer and fluorescein isothiocyanate-functionalized silane as the fluorescent monomer. After incubation with the multiplex pathogens, the fluorescent molecularly imprinted photonic microspheres can specifically capture the target pathogenic bacteria, and their fluorescence intensities can report the concentrations of the pathogens in samples. The new microsphere microarray showed wide linear detection ranges (10 to 10⁹ CFU/mL for Salmonella, 10² to 10⁶ CFU/mL for Shigella, and 10 to 10⁷ CFU/mL for Escherichia coli O157:H7) and low limits of detection (LODs) (3 CFU/mL for Salmonella, 20 CFU/mL for Shigella, and 1 CFU/mL for E. coli O157:H7) for multiplex pathogens. The new system does not require molecular probes such as antibody, aptamer, or DNA sequence and without enrichment culture and DNA amplification processes. The newly developed method has great potential applications in rapid, cost-effective, and high-throughput simultaneous detection of multiplex foodborne pathogens.