Conducting Polyaniline Nanowire and Its Applications in Chemiresistive Sensing

Abstract

One dimensional polyaniline nanowire is an electrically conducting polymer that can be used as an active layer for sensors whose conductivity change can be used to detect chemical or biological species. In this review, the basic properties of polyaniline nanowires including chemical structures, redox chemistry, and method of synthesis are discussed. A comprehensive literature survey on chemiresistive/conductometric sensors based on polyaniline nanowires is presented and recent developments in polyaniline nanowire-based sensors are summarized. Finally, the current limitations and the future prospect of polyaniline nanowires are discussed.

Characterization of an hrp-aox-polyaniline-graphite composite biosensor

“…Song and Choi [32] have reported that the most conductive form of PANI is the fully protonated, half-oxidized emeraldine salt form. A decrease in conductivity was observed when the polymer was deprotonated or either fully oxidized or reduced.…”

Synthesis and Characterization of PANI-MWCNTs Supported Nano Hybrid Electrocatalysts

“…One of them is PANI (polyaniline), which has three main distinguishable oxidation states, namely, the fully reduced (leucoemeraldine), the half oxidized (emeraldine), and the fully oxidized (pernigraniline) state, with virtually an infinite number of possible oxidation states existing in between. Protonation of the polymer, also known as doping, is the mechanism by which polyaniline becomes electrically conductive [33]. The classical chemical synthesis involves the direct oxidation of aniline monomers by chemical oxidants.…”

Polyaniline-based biosensors

“…The unprotonated and protonated forms of PANI are known as base and salt, respectively. 10 Figure 2 shows different base and salt forms of PANI in its three redox forms. Conclusively, the conductivity of PANI can be tuned by using different doping agents, varying the extent of doping, and also by controlling the chain length and morphology including the dimensions and porosity of PANI.…”

“…The presence of two redox couples at appropriate electrochemical potential further helps PANI in facilitating the enzyme-polymer charge transfer processes, and makes it an ideal candidate to develop electrochemical biosensors. 10 Consistent and sensitive interdependence between the electrochemical response and the pH of the electrolytic solution opens new avenues to develop another set of pH sensitive electrochemical biosensors specifically for the analytes that generate either acidic or basic moieties as end products of the biochemical reaction, eg, triglycerides.…”