A rapid and sensitive heterogeneous immunoelectrochemical assay using disposable electrodes

Area of Science:

• Electrochemistry
• Biotechnology
• Immunochemistry

Background:

• Development of sensitive and rapid detection methods is crucial in diagnostics.
• Enzyme-linked immunoassays are widely used but can be time-consuming.
• Electrochemical techniques offer potential for sensitive and fast biomolecule detection.

Purpose of the Study:

• To develop a novel enzyme-tagged immuoelectrochemical assay.
• To utilize disposable carbon felt discs as both electrodes and solid phase.
• To enable rapid and sensitive quantification of analytes like mouse IgG and bacteria.

Main Methods:

• Immobilization of antibodies onto carbon felt discs using a diaminoalkane-biotin-avidin-biotin bridge.
• Use of alkaline phosphatase as a label for enzymatic amplification.
• Monitoring antibody binding via electro-oxidation of aminophenol, a product of enzymatic reaction.
• Employing disposable carbon felt electrodes for heterogeneous solid-phase immunoassay.

Main Results:

• A model system for mouse IgG determination showed a wide calibration curve from 10 pg/ml to 100 µg/ml.
• The assay demonstrated rapid performance, with a single determination completed within 20 minutes.
• The system proved effective for rapid quantitation of low bacterial concentrations (approx. 80 organisms/ml).

Conclusions:

• The developed enzyme-tagged immuoelectrochemical assay is a rapid and sensitive method.
• Disposable carbon felt discs serve effectively as electrodes and solid phase supports.
• This assay platform shows promise for diverse diagnostic applications, including bacterial detection.