Magnetic bead-based DNA detection with multi-layers quantum dots labeling for rapid detection of Escherichia coli O157:H7

This work demonstrated the feasibility of detecting 250 zM Escherichia coli O157:H7 eaeA target DNA by using a magnetic bead-based DNA detection assay with designed labeling strategy within 40–60 min. The magnetic beads were used as the solid support for the binding probe and isolated the target DNA from the sample. The detection signals could be amplified from the multi-layers biotin–streptavidin conjugated quantum dots based on binding with specific designed biotinlyted linker. This assay method would provide a simple, rapid, and ultra-sensitive detection method for DNA or other biomolecular analysis.