A Chemiluminescence Based Optical Biosensor Coupled with Immunomagnetic Separation for the Detection of β-Glucuronidase from Escherichia coli
نویسندگان
چکیده
A biosensor was developed using a magnetic focusing optical waveguide (glass tubular probe) for the detection of glucuronidase (GUS) from Escherichia coli based on immunomagnetic separation and chemiluminescent measurement. The magnetic focusing resulted in a lower chemiluminescent signal than that obtained without magnetic-focusing, mainly due to the diffusion of the chemiluminescent reaction products into the solution rather than concentrating around the GUS enzyme captured by the antibodies on the paramagnetic beads. A microwell format was also tested for the chemiluminescent assay. A linear relationship was observed between log-GUS concentration and log-chemiluminescent signal for the microwell and magnetic focusing formats with a limit of detection as low as 100 and 1000 pg GUS/mL, respectively. The microwell format had the potential to be improved for higher sensitivity. The procedure was simple and rapid, and the whole assay could be completed in 70 min.
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