ABSTRACT
A paper chip device-based recombinase polymerase amplification (RPA) method was developed for highly sensitive and selective single-step detection of foodborne pathogens. A paper chip was manufactured by simply stacking functional papers. RPA reagents and fluorescent probe were dried on the reaction zone of a patterned poly(ether sulfone) membrane. The RPA reaction was initiated by adding pathogen DNAs into an injection hole. Paper chip-based analysis of pathogens showed optimal performance at 37 °C for 20 min and the results were comparable to those obtained with solution-based RPA reactions. Based on the paper chip-based fluorescence signal, Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium were simultaneously detected with detection limits of 102 cfu/mL. The diagnostic utility of the device was demonstrated by the reliable detection of E. coli and S. aureus present in spiked milk. This ready-to-use device could be integrated with simple nucleic acid extraction for food pathogen detection in resource-limited settings.
Subject(s)
Food Microbiology , Lab-On-A-Chip Devices , Nucleic Acid Amplification Techniques/methods , Paper , Recombinases/metabolismABSTRACT
A simple and eco-friendly method has been developed for the one-pot synthesis of DNA-copper nanoflowers that exhibit high loading efficiencies, low cytotoxicities, and strong resistance against nucleases.