Electrochemical Biosensor Based on Hairy Core-Shell Particles: Effect of Core Conductivity

Area of Science:

• Biomaterials Science
• Electrochemistry
• Biosensor Technology

Background:

• Enzyme immobilization on core-shell carriers enhances stability and reusability.
• Poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) polymer brushes facilitate high enzyme loading.
• Trametes versicolor laccase (TvL) is a key enzyme for electrochemical biosensing applications.

Purpose of the Study:

• To investigate the influence of different core materials on the performance of PDMAEMA-grafted hairy core-shell carriers with immobilized TvL.
• To evaluate biosensor characteristics, including sensitivity and limit of detection, for hydroquinone (HQ) detection.
• To understand the relationship between carrier properties (conductivity, surface area) and biosensor performance.

Main Methods:

• Synthesis of hairy core-shell carriers with various core materials (silver, silver-Janus, carbon nanotubes, carbon black, silica).
• Grafting of PDMAEMA polymer brushes and immobilization of TvL.
• Electrochemical characterization of biosensors for HQ detection in aqueous solutions.

Main Results:

• All tested carriers demonstrated high catalytic efficiency and selectivity for HQ detection.
• Sensor sensitivity was comparable across different core materials.
• Limit of detection was significantly influenced by carrier conductivity and active surface area, with conductive carriers sometimes performing worse due to capacitive currents.

Conclusions:

• The choice of core material is critical for optimizing biosensor performance, particularly for the limit of detection.
• High conductivity and surface area of the carrier do not guarantee enhanced biosensor performance and can be detrimental.
• Understanding the interplay between carrier properties and electrochemical phenomena (capacitive vs. faradaic currents) is essential for biosensor design.