Electrochemical Assay for a Total Cellulase Activity with Improved Sensitivity

Area of Science:

• Biochemistry
• Electrochemistry
• Enzyme Assays

Background:

• Enzymatic activity analysis is crucial for industries like food, textiles, and bioethanol production.
• Current methods for enzyme analysis are often slow, expensive, or lack sensitivity.
• Cellulase is a key hydrolytic enzyme with significant industrial relevance.

Purpose of the Study:

• To develop a simple, fast, and highly sensitive electrochemical assay for determining total cellulase activity.
• To provide a cost-effective alternative to existing optical assays for research and industrial applications.

Main Methods:

• An electrochemical assay utilizing a soluble redox indicator (ferricyanide) and nitrocellulose films was developed.
• The assay measures changes in ferricyanide electrochemical signals on graphite electrodes modified with nitrocellulose films before and after cellulase treatment.
• Cellulase activity is correlated with the increased permeability of nitrocellulose films and enhanced electrode surface area accessible to ferricyanide.

Main Results:

• The electrochemical assay demonstrated high sensitivity (10^-8 U per assay) for cellulase activity.
• The assay achieved results 10³-10⁴-fold more sensitive than standard commercial optical assays.
• Trichoderma and Aspergillus niger cellulase activities were successfully determined within a 5-minute timeframe.

Conclusions:

• The developed electrochemical assay is a highly sensitive and rapid method for quantifying cellulase activity.
• This approach offers a cost-effective and prospective alternative for both research and automated industrial enzyme analysis.
• The assay's simplicity and efficiency make it suitable for widespread adoption in relevant industries.