Poly(Thiophene)/Graphene Oxide-Modified Electrodes for Amperometric Glucose Biosensing.

Area of Science:

• Electrochemistry
• Biosensors
• Analytical Chemistry
• Materials Science

Background:

• Accurate glucose determination is crucial in analytical, medicinal, and food chemistry.
• Electrochemical biosensors offer a promising avenue for analyte detection.
• Efficient enzyme immobilization is key to biosensor performance.

Purpose of the Study:

• To develop and evaluate an electrochemical biosensor for glucose detection.
• To investigate the use of a novel thiophene monomer (dTT-bT) for enzyme immobilization.
• To compare the performance of biosensors with and without graphene oxide modification.

Main Methods:

• Electrodeposition of a conducting polymer film from (2,5-di(2-thienyl)thieno [3,2-b]thiophene (dTT-bT) on Pt, GC, and Au electrodes.
• Immobilization of glucose oxidase (GOx) enzyme onto the polymer film.
• Modification of the polymer film with graphene oxide on a glassy carbon electrode before GOx deposition.
• Electrochemical characterization and performance evaluation of the biosensors for glucose detection.

Main Results:

• The dTT-bT polymer effectively immobilized GOx on various electrode surfaces.
• The biosensor incorporating graphene oxide exhibited superior analytical performance.
• Optimal performance with graphene oxide: linear dynamic range (1.0-10 mM), limit of detection (0.036 mM), and sensitivity (9.4 µA mM^-1 cm^-2).
• The biosensor demonstrated successful application in determining glucose in fruit juices with evaluated interference from other sugars and ascorbic acid.

Conclusions:

• The dTT-bT electrogenerated polymer film is a viable material for GOx immobilization.
• Graphene oxide modification significantly enhances the analytical capabilities of the glucose biosensor.
• This developed biosensor shows potential for practical applications in food analysis.