Conducting polymers (CPs) represent a sizeable range of useful organic substances. Their unique electrical, chemical, and physical properties; reasonable price; simple preparation; small dimensions; and large surface area have enabled researchers to discover a wide variety of uses, including sensors, supercapacitors, solar cells, batteries, biochemical applications, and electrochromic devices. To promote the success of CPs, unique composite materials have been prepared with metals or steel oxides. The goal of this overview is to characterize the electrochemical sensor utility of CPs and their composites and to categorize future components of electrochemical sensing materials. CPs have been comprehensively applied over a wide range of variable industrial fields; such CPs have used many new materials with diverse compositions that are utilized as electrochemical sensors and biosensors. These materials have been fabricated inside numerous analytical instruments that are applied in healthcare settings and clinical, environmental, food, and pharmaceutical laboratories. Electrochemical sensors are essentially based on CPs and/or their corresponding composite materials. Therefore, the present work provides a brief illustration of electrochemical sensor and biosensor applications for the most important conducting polymer composite materials. Polyaniline (PANI), poly(o-toluidine) (PoT), and poly(o-anisidine) (PoAN) were considered in this study. Moreover, the most important electrochemical properties of these conducting polymer composite materials are discussed.

Composite Material–Based Conducting Polymers for Electrochemical Sensor Applications: a Mini Review

Poly(o-anisidine) (POA) was formed by successive cyclic voltammetry in monomer solution containing sodium dodecyl sulfate (SDS) at the surface of carbon paste electrode. Then Ni(II) ions were incorporated to electrode by immersion of the polymeric modified electrode having amine group in 0.1 M Ni(II) ion solution. Cyclic voltammetric and chronoamperometric experiments were used for the electrochemical study of this modified electrode; a good redox behavior of Ni(OH)2/NiOOH couple at the surface of electrode can be observed. The capability of this modified electrode for catalytic oxidation of folic acid was demonstrated. The amount of α and surface coverage (Γ*) of the redox species and catalytic chemical reaction rate constant (k) for folic acid oxidation were calculated. The catalytic oxidation peak current of folic acid was linearly dependent on its concentration and a linear calibration curve was obtained in the range of 0.1 to 5 mM with a correlation coefficient of 0.9994. The limit of detection (3σ) was determined as 0.091 mM. This electrocatalytic oxidation was used as simple, selective and precise voltammetric method for determination of folic acid in pharmaceutical preparations.

Electrocatalytic Oxidation of Folic Acid on Carbon Paste Electrode Modified by Nickel Ions Dispersed into Poly(o‐anisidine) Film

Investigations on the performance of poly(o-anisidine)/graphene nanocomposites for the electrochemical detection of NADH

Fabrication of neurotransmitter dopamine electrochemical sensor based on poly(o-anisidine)/CNTs nanocomposite

A strategy to promote the electroactive platform adopting poly(o-anisidine)-silver nanocomposites probed for the voltammetric detection of NADH and dopamine.

Polyanisidine films doped with two different anions, viz., perchlorate and paratoluene sulphonate anions are prepared electrochemically on a gold substrate. Polyanisidine films doped with the anions aid in retaining the redox conductivity of the polyanisidine films. This behaviour is similar to that of polyaniline films. Unlike polyaniline films, even smaller ions like perchlorate and paratoluene sulphonate are sufficient for retaining the redox conductivity of the film, which may be primarily due to the compact, non-permeant films formed during electropolymerization. The films are found to be suitable for the immobilization of glucose oxidase enzyme and are found to be an efficient sensing matrix for glucose. The films also exhibited catalytic activity towards the oxidation of NADH. These studies indicate the usefulness of polyanisidine–anion films as sensing platform for biomolecules.

B. Angaleeswari

Papers

Poly(o-anisidine)–anion composite films as sensing platform for biological molecules