Preparation of an Amperometric Glucose Biosensor on Polyaniline‐Coated Graphite

Abstract

Control of glucose concentration has tremendous significance in medical diagnosis, pharmaceuticals, food, and fermentation industries. Herein, we report on the fabrication of a facile, low-cost, and sensitive enzyme-based amperometric sensor using the electrochemically deposited polyaniline (PANI) film on a graphite electrode. PANI was deposited from an aqueous solution of 0.2 M aniline in 1.0 M hydrocholoric acid (HCl) by cyclic voltammetry (CV). Surface morphology and composition characterization of the PANI film were carried out by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared (FTIR) spectroscopy. Potentiostatic immobilization of glucose oxidase (GOX) enzyme in the PANI film was carried out at 0.75 V to fabricate an amperometric glucose biosensor (GOx/PANI/graphite biosensor). The glucose concentration response of the prepared sensor was studied amperometrically by detecting hydrogen peroxide (H2O2). The detection of H2O2 was optimized by calibrating the effects of pH, reduction potential, and background current. A reduction potential of -0.4 V at pH 6 was the best combination to get a maximum amperometric response of the GOx/PANI/graphite biosensor. A stable current response was obtained in 4 min with a high reproducibility in linearity within the concentration range of 0.01 M-0.1 M D-glucose. Therefore, the fabricated GOx/PANI/graphite biosensor could be a promising candidate for glucose sensing.

Advances in Electrochemical Sensors for Detecting Analytes in Biofluids

“…One area of further improvement for the enzymatic sensors is surface modification of WE (e.g., microstructural modification of polymeric layer, partial functionalization of each layer), which can lower the response time of the EC sensor. [54] In contrast to enzymatic sensors, typical non-enzymatic sensors use a metal oxide (e.g., CuO, NiFe oxides, NiCo-layered double hydroxide (NiCo-LDH)) or combined noble metal and carbon structure to serve as an electrocatalyst for electron transfer during the glucose oxidation reaction. [55] As the catalytic material reacts with glucose, electrons are transferred by electro-oxidation and reduction reactions.…”

Electrospun nanofiber-based glucose sensors for glucose detection

“…Polyaniline (PANI) is a π–π conjugated polymer synthesized by chemical or electrochemical oxidation of a monomer ( Popov et al, 2021 ). The unique π–π-conjugated structure acts as a redox medium between the redox center and the enzyme electrode, facilitating electron transfer to the electrode ( Neupane et al, 2021 ). Because PANI has strong effective reaction and anti-interference ability between enzyme and electrode, it has optimal sensing performance.…”

An Enzymatic Glucose Biosensor Based on a Pencil Graphite Electrode Modified with Naphthalenedimide/3,4‐Ethylenedioxythiophene Conjugated Polymer and Enriched with Au Nanoparticles

“…The response of the prepared biosensor to glucose concentration was analyzed amperometrically by detecting hydrogen peroxide (H 2 O 2 ). The biosensor showed good linearity over the 0.01 M‐0.1 M D‐glucose concentration range [4] . In addition, when the surface of the conjugated polymer coated electrode is modified with metal‐based nano and composite materials, it is possible to obtain biosensors with a large surface area and activity, high electrical conductivity and biocompatible.…”

“…There are numerous methods in practice for glucose determination, such as gas chromatography, colorimetric capillary electrophoresis, high performance liquid chromatography (HPLC), electrochemiluminescence, polarimetry and biosensors. The use of glucose biosensors is low cost, reliable and responsive [4] . Because of these features, research on glucose sensors are very popular.…”

“…Therefore, glucose biosensors have a share of approximately 85 % in the biosensor industry [5] . For a glucose biosensor to react, the enzyme must be immobilized on the electrode surface [4] . Enzymatic glucose biosensors are generally based on two oxidoreductases: Glucose oxidase (GOx) [6–9] and Glucose dehydrogenase (GDH) [10–12] .…”