Bienzyme based biosensing platform using functionalized carbon nanotubes.

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Biotechnology

Background:

• Amperometric biosensors are crucial for detecting biologically relevant molecules.
• Developing sensitive and selective detection methods for glucose and hydrogen peroxide is important in diagnostics and environmental monitoring.
• Enzyme-based biosensors offer high specificity but require careful immobilization strategies.

Purpose of the Study:

• To design and characterize a novel amperometric transducer for simultaneous detection of glucose and hydrogen peroxide.
• To explore the use of Toluidine blue (TB) functionalized multiwalled carbon nanotubes (MWNTs) for enzyme immobilization.
• To evaluate the electrochemical performance of the developed nanobiocomposite electrode.

Main Methods:

• Bienzyme-channelling configuration using glucose oxidase (GOD) and horseradish peroxidase (HRP).
• Immobilization of enzymes onto TB-functionalized MWNTs via carbodiimide reaction.
• Preparation of the MWNT/TB/GOD/HRP/Nf nanobiocomposite.
• Characterization using scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV).

Main Results:

• Successful fabrication of a nanobiocomposite electrode (MWNT/TB/GOD/HRP/Nf).
• Linear detection ranges achieved: 1.4 x 10(-7)-1.6 x 10(-3) M for glucose and 6.8 x 10(-8)-1.7 x 10(-3) M for H2O2.
• Demonstrated sensitive detection of both analytes at very low applied potentials, reducing interference.

Conclusions:

• The developed bienzyme biosensor based on TB-functionalized MWNTs is effective for detecting glucose and H2O2.
• The nanobiocomposite electrode exhibits excellent electrochemical performance and stability.
• The low-potential operation minimizes interference, enhancing the reliability of the biosensor for practical applications.