Bioaffinity sensors based on conducting polymers: A short review

The development of new electrode materials has expanded the range and classes of detectable compounds using electroanalytical methods. Conducting electroactive polymers (CEPs) have been demonstrated to have remarkable sensing applications through their ability to be reversibly oxidized or reduced by applying electrical potentials. For biosensing applications, CEPs combine the role of matrix immobilization template and the generation of analytical signals. The focus of the present article is to provide a brief review of conducting polymer-based bioaffinity sensors and to provide insights into the possible mechanisms of signal generation. The interfacial processes between the protein and CEP, leading to signal generation during bioaffinity reaction, is believed to occur via the positive charges delocalized along the polymer chains, thus inducing a change in the capacitance of the CEP material.