PEDOT:PSS - A suitable interface for the enzyme PQQ-GDH on electrodes

Area of Science:

• Electrochemistry
• Biotechnology
• Materials Science

Background:

• Enzyme immobilization on electrodes is crucial for biosensing and bioenergetics.
• Conducting polymers like PEDOT:PSS offer promising platforms for electrochemical applications.

Purpose of the Study:

• To develop a minimalistic manufacturing strategy for enzyme electrodes.
• To demonstrate mediator-free, oxygen-independent glucose detection using PQQ-GDH immobilized on PEDOT:PSS.
• To investigate the performance and stability of the enzyme electrode.

Main Methods:

• Fabrication of enzyme electrodes using PEDOT:PSS on gold substrates.
• Adsorptive immobilization of pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH).
• Glucose detection using cyclic voltammetry and faradaic impedance spectroscopy (f-EIS).

Main Results:

• Significant catalytic currents were observed for glucose detection.
• An apparent K_m-value of 0.16 ± 0.03 mM was determined.
• The enzyme electrode exhibited stability over a pH range of 5.5–7.2 and tunable catalytic signals.
• f-EIS successfully monitored enzymatic activity, supporting direct electron transfer (DET).

Conclusions:

• PEDOT:PSS is an effective platform for mediator-free bioelectrocatalysis.
• The developed enzyme electrode shows potential for advanced biosensing applications.
• This work facilitates the integration of bioelectrocatalysis with flexible electronics.