Fabrication and characterization of glucose sensors based on a microarray H2O2 electrode

Area of Science:

• Electrochemistry
• Biosensors
• Materials Science

Background:

• Development of accurate and reliable glucose sensors is crucial for diabetes management.
• Amperometric enzyme-based sensors offer a promising approach for glucose monitoring.

Purpose of the Study:

• To develop and characterize a novel amperometric glucose sensor.
• To optimize the design of a microarray electrode (MAE) for enhanced electrochemical performance.

Main Methods:

• Fabrication of an amperometric H2O2 MAE using standard planar processing.
• Modification of the MAE with an immobilized glucose oxidase (GOD) membrane and a Nafion diffusion limiting membrane.
• Electrochemical characterization of six different MAEs, evaluating band width and length.
• Testing the glucose sensor's performance at 37°C in a phosphate buffer solution (pH 7.0).

Main Results:

• The MAE with the narrowest band width (10 microns) exhibited the best electrochemical performance.
• The developed glucose sensor showed a linear detection range of 0.5–40 mM glucose.
• Key performance metrics included a sensitivity of 7.1 ± 0.5 nA/mM, background current of 2 ± 0.5 nA, response time of 30 s, coefficient of variation (CV) of 3.4%, and long-term stability of 6 days.

Conclusions:

• The optimized MAE design, particularly the narrow band width, significantly improves sensor performance.
• The developed glucose sensor demonstrates high sensitivity, rapid response, and good stability, making it suitable for glucose monitoring.