An antifouling coating that enables affinity-based electrochemical biosensing in complex biological fluids

Area of Science:

• Electrochemistry
• Biomaterials Science
• Nanotechnology
• Point-of-Care Diagnostics

Background:

• Electrochemical detection in biological fluids is crucial for diagnostics but hindered by electrode biofouling and signal loss.
• Existing point-of-care devices face commercialization challenges due to rapid sensitivity degradation.
• Need for robust electrode coatings to maintain performance in complex matrices like human plasma.

Purpose of the Study:

• To develop a simple and robust antifouling coating for electrochemical biosensors.
• To enhance electrode stability and electron transfer in complex biological fluids.
• To enable sensitive and reliable affinity-based electrochemical detection for home healthcare applications.

Main Methods:

• Fabrication of a three-dimensional porous matrix using cross-linked bovine serum albumin (BSA).
• Integration of conductive nanomaterials (gold nanowires, gold nanoparticles, or carbon nanotubes) within the BSA matrix.
• Functionalization of the nanocomposite with specific antibodies for target analyte quantification.

Main Results:

• The BSA-nanomaterial nanocomposite coating demonstrated robust antifouling properties.
• Electrodes preserved 88% of their original signal after one month of exposure to unprocessed human plasma.
• Antibody-functionalized sensors achieved sensitive quantification of anti-interleukin-6 in plasma.

Conclusions:

• The developed nanocomposite coating effectively prevents biofouling and non-specific interactions.
• This approach significantly enhances the stability and electron transfer efficiency of electrochemical biosensors.
• The easy preparation and stability of the biosensors allow for operation in complex biological fluids, advancing point-of-care diagnostics.