Tunable 3D nanofibrous and bio-functionalised PEDOT network explored as a conducting polymer-based biosensor.

Area of Science:

• Materials Science
• Electrochemistry
• Biosensor Technology

Background:

• All-polymer biosensors require conducting polymers with electrochemical activity, nanostructure, and bioconjugation functionality.
• Traditional biosensors often rely on nanocatalysts like carbon materials, metals, or dyes, limiting their scope.

Purpose of the Study:

• To develop a facile method for creating a bi-functional PEDOT interface (Nano-PEDOT-COOH) with tunable 3D nanofibrous networks and carboxylic acid groups.
• To investigate the electrochemical properties and biosensing capabilities of the developed Nano-PEDOT-COOH interface.

Main Methods:

• Controlled co-polymerisation of EDOT and EDOT-COOH monomers using tetrabutylammonium perchlorate as a soft-template.
• Tuning the monomer ratio to control nanofiber diameter and carboxylic acid group density.
• Immobilisation of lactate dehydrogenase via EDC/S-NHS chemistry for lactate detection.

Main Results:

• Successfully prepared Nano-PEDOT-COOH with tunable fiber diameters (15.6–70.0 nm) and carboxylic acid densities (0.03–0.18 μmol cm⁻²).
• Achieved a wide linear range (20–960 μM) and high sensitivity (0.224 μA μM⁻¹ cm⁻²) for NADH detection.
• Fabricated a lactate biosensor with a response time <10 s over a 0.05–1.8 mM range.

Conclusions:

• The developed Nano-PEDOT-COOH interface is a promising platform for advanced all-polymer biosensors.
• The tunable nanostructure and carboxylic acid groups enable efficient bioconjugation and sensitive detection.
• This approach offers potential for multi-analyte biosensor development by coupling with various biorecognition molecules.