Diboronic-Acid-Based Electrochemical Sensor for Enzyme-Free Selective and Sensitive Glucose Detection.

Area of Science:

• Electrochemistry
• Biosensors
• Analytical Chemistry

Background:

• Existing boronic acid immobilized electrodes lack selective, signal-increasing glucose detection.
• High glucose concentrations can cause sensor malfunctions, necessitating proportional signal output.

Purpose of the Study:

• To synthesize a new diboronic acid derivative for fabricating glucose-selective electrodes.
• To develop an electrochemical sensor with a signal that increases proportionally with glucose concentration.

Main Methods:

• Fabrication of diboronic acid derivative-immobilized electrodes.
• Cyclic voltammetry and electrochemical impedance spectroscopy using Fe(CN)63-/4- redox pair.
• Testing glucose detection in phosphate-buffered saline (PBS) and artificial sweat.

Main Results:

• Electrochemical signals (peak current, electron-transfer kinetics) increased proportionally with glucose concentration (0-500 mg/dL).
• Linear detection range of 40-500 mg/dL with limits of detection of 31.2 mg/dL (CV) and 21.5 mg/dL (EIS).
• Demonstrated selectivity for glucose over other sugars (galactose, fructose, mannitol) and maintained 90% performance in artificial sweat.

Conclusions:

• The synthesized diboronic acid derivative is a promising receptor for developing long-term electrochemical glucose sensors.
• The fabricated electrode shows potential for accurate and selective glucose monitoring in various conditions.