Potentiometric study of antioxidant activity: development and prospects

Area of Science:

• Biochemistry
• Analytical Chemistry
• Electrochemistry

Background:

• Oxidative stress results from an imbalance between reactive oxygen species (ROS) production and antioxidant system capacity.
• This imbalance can lead to various pathological conditions in humans.
• Measuring integrated antioxidant activity (AOA) is crucial for understanding and mitigating these effects.

Purpose of the Study:

• To critically review existing methods for measuring integrated antioxidant activity (AOA).
• To propose and validate electrochemical potentiometry as a highly promising method for AOA assessment.
• To investigate the theoretical and thermodynamic basis for a mediator system used in potentiometric AOA measurements.

Main Methods:

• Critical review of existing AOA measurement techniques.
• Development and application of an electrochemical potentiometric method using a mediator system.
• Thermodynamic and kinetic analysis of antioxidant-mediator interactions.
• Correlation studies comparing potentiometric data with independent analytical methods.

Main Results:

• Electrochemical potentiometry is identified as the most suitable method for measuring integrated AOA due to its alignment with oxidative stress mechanisms.
• The theoretical rationale and thermodynamic basis for a specific mediator system were established.
• Kinetic studies elucidated the reaction mechanisms between antioxidants and the mediator system.
• High correlation was observed between the proposed potentiometric method and independent analytical techniques, confirming reliability and accuracy.
• The method was successfully applied to diverse samples, including nutritional supplements, food, and blood fractions.

Conclusions:

• Electrochemical potentiometry offers a reliable and accurate approach for assessing integrated antioxidant activity.
• The validated mediator system provides a robust foundation for potentiometric AOA measurements.
• This method has broad applicability across various matrices, from supplements to biological fluids.