Conducting polymer-based electrochemical DNA biosensing

Deoxyribonucleic acid (DNA) is one of the most important molecules of life since it carries heritage information and instructs the biological synthesis of proteins and enzymes through the process of replication and transcription of genetic information, both in living organisms and in many viruses. Detection of DNA sequences receives much attention. It plays a major role in clinical, forensic, environmental, food, and pharmaceutical applications. It is also important to understand the structural properties of DNA and the action mechanism of some antitumor and antivirus drugs to design new and more efficient DNA-targeted drugs. Among many DNA detection methods, electrochemical ones, which have many advantages over time-consuming traditional methods, are very favorable. Electrochemistry offers sensitive, accurate, simple, and low-cost analysis. Thus, electrochemical biosensors have classified as one of the most used biosensor types in terms of detecting DNA, DNA hybridization, and DNA-anticancer drug interaction biosensing. The genetic information is encoded as a sequence of nucleotides named as guanine (G), adenine (A), thymine (T), and cytosine (C) which are electroactive. This makes electrochemistry very attractive for DNA detection. Furthermore, in order to enhance the signals of DNA bases, various platforms such as conducting polymers and nanomaterials are used. Conducting polymers-based approaches provides suitable immobilization surface for DNA by increasing the electroactive surface area of the electrode material. In addition, they serve as robust and stable surfaces.