Highly sensitive electrochemical immunosensor for IgG detection based on optimized rigid biocomposites

Area of Science:

• Electrochemistry
• Biosensors
• Materials Science

Background:

• Development of sensitive and reliable immunosensors is crucial for various analytical applications.
• Graphite-epoxy composites offer promising electrochemical properties for transducer development.
• Optimization of material composition and assay parameters is essential for enhancing immunosensor performance.

Purpose of the Study:

• To construct and optimize novel immunosensors based on graphite-epoxy composites incorporating Rabbit Immunoglobulin G (RIgG).
• To improve the electrochemical properties and analytical performance of immunocomposite electrodes.
• To determine the optimal graphite loading and antigen-antibody ratio for enhanced sensitivity and signal-to-noise ratio.

Main Methods:

• Fabrication of graphite-epoxy composite electrodes with incorporated RIgG.
• Electrochemical characterization using electrochemical impedance spectroscopy and cyclic voltammetry.
• Optimization of graphite loading (16-17%) and antigen-antibody ratio for a competitive assay using alkaline phosphatase-labeled antibody and hydrogen peroxide substrate.

Main Results:

• Optimal graphite loading for sensitive electrode performance was determined to be between 16% and 17%.
• The developed immunosensors demonstrated suitable sensitivity, high electron-transfer rate, and high signal-to-noise ratio.
• Significant reduction in the optimal antigen-antibody ratio was achieved through assay optimization.

Conclusions:

• Graphite-epoxy composites provide a viable matrix for constructing high-performance immunosensors.
• The optimized immunosensor composition and assay conditions significantly enhance detection capabilities for RIgG.
• This work presents a novel approach to immunosensor development with improved analytical efficiency and reduced reagent consumption.