Potentiometric method for substrate analysis using immobilized NAD + -dependent oxidoreductase enzymes

Area of Science:

• Biochemistry
• Electrochemistry
• Analytical Chemistry

Background:

• Coenzyme-dependent oxidoreductases are crucial enzymes in metabolic pathways.
• Enzyme electrodes offer sensitive and selective methods for analyte detection.
• Immobilization techniques are vital for enzyme stability and reusability in biosensors.

Purpose of the Study:

• To develop and evaluate novel enzyme electrodes for substrate analysis.
• To utilize immobilized glucose dehydrogenase and alcohol dehydrogenase for measuring substrate concentrations.
• To demonstrate the applicability of the developed system for various coenzyme-dependent oxidoreductase substrates.

Main Methods:

• Immobilization of glucose dehydrogenase and alcohol dehydrogenase in polyacrylamide gel on a platinum grid matrix.
• Use of nicotinamide adenine dinucleotide (NAD+) as a cofactor.
• Employing ferricyanide as a redox mediator and electroactive species for electrochemical detection.

Main Results:

• Successful construction and performance evaluation of enzyme electrodes for glucose and ethanol.
• Demonstrated the feasibility of measuring substrate concentrations in buffered aqueous solutions.
• Quantified glucose and ethanol using the developed electrochemical system.

Conclusions:

• The developed enzyme electrode system provides a robust method for substrate analysis.
• The methodology is adaptable for a wide range of coenzyme-dependent oxidoreductase substrates.
• This approach enhances biosensing capabilities for various analytes.