Amperometric l-ascorbic acid biosensors equipped with enzyme micelle membrane

Area of Science:

• Biomedical Engineering
• Electrochemistry
• Biosensors

Background:

• Ascorbate oxidase (ASOD) is an enzyme that catalyzes the oxidation of l-ascorbic acid (AsA).
• Developing stable and sensitive biosensors for AsA detection is crucial for various applications.
• Polymaleimidostyrene (PMS) can form stable micelle structures with enzymes.

Purpose of the Study:

• To develop a stable and sensitive amperometric biosensor for l-ascorbic acid (AsA) detection.
• To utilize ascorbate oxidase (ASOD) immobilized in a polymaleimidostyrene (PMS) membrane.
• To investigate the performance of the biosensor on different electrode materials.

Main Methods:

• Immobilization of ASOD within a PMS membrane to form a stable micelle structure.
• Coating the ASOD-PMS membrane onto aminated glassy carbon electrodes (AGCE) and gold electrodes (AuE).
• Amperometric detection of AsA based on oxygen consumption at a cathodic applied potential (-0.5V vs. Ag/AgCl).

Main Results:

• The ASOD-PMS membrane formed a stable, oxygen-permeable hydrophobic layer on the electrodes.
• The developed AsA sensors exhibited good sensitivity and rapid response times (within 1 minute).
• A linear relationship between current and AsA concentration was observed from 5µM to 0.4mM using AGCE.

Conclusions:

• The ASOD-PMS biosensor provides a sensitive and selective method for AsA detection.
• The use of cathodic potential effectively avoids interference from other reducing agents.
• This approach offers a promising platform for developing robust amperometric biosensors.