Electron-transfer mediator for a NAD-glucose dehydrogenase-based glucose sensor

Area of Science:

• Electrochemistry
• Biosensors
• Materials Science

Background:

• Development of efficient electron-transfer mediators is crucial for biosensor performance.
• Nicotinamide adenine dinucleotide-dependent glucose dehydrogenase (NAD-GDH) is a key enzyme for glucose sensing.
• Screen-printed carbon electrodes (SPCEs) offer a platform for disposable electrochemical sensors.

Purpose of the Study:

• Synthesize and characterize a new electron-transfer mediator, FePhenTPy.
• Develop a disposable amperometric glucose sensor using FePhenTPy and NAD-GDH.
• Evaluate and optimize the performance and stability of the developed glucose sensor.

Main Methods:

• Paal-Knorr condensation for FePhenTPy synthesis.
• Spectroscopic (FTIR, NMR, MS) and electrochemical (voltammetry, impedance) characterization.
• Fabrication of glucose sensor on SPCE with FePhenTPy and NAD-GDH, incorporating reduced graphene oxide (RGO).

Main Results:

• FePhenTPy was successfully synthesized and characterized.
• The glucose sensor demonstrated a wide dynamic range (30-600 mg/dL) and a low detection limit (12.02 ± 0.6 mg/dL).
• Enhanced sensor performance was observed with the addition of RGO, and interference from common substances was effectively eliminated using a Nafion/lead(IV) acetate coating.

Conclusions:

• The novel FePhenTPy mediator facilitates efficient electron transfer for NAD-GDH based glucose sensing.
• The developed disposable glucose sensor exhibits excellent sensitivity, selectivity, and stability.
• The sensor shows high reliability for glucose determination in artificial and human whole blood samples.