Studies On Electrochemical DNA Biosensors Based On Electropolymerized Films And Self-Assembly Monolayers

DNA electrochemical sensors hold an enormous potential for disease diagnosis, drug screening or forensic applications and development of an inexpensive, easy-to-use, fast response device stays therefore in the center of interest of many scientists. At present, many new electrochemical procedures are under intense investigation in order to get a fast, sensitive and selective quantification of nucleic acids and to meet the new challenges connected to the application of DNA biosensors in different fields. Among these new methods, electrochemical sensors offer powerful tools for converting the hybridization event into an analytical signal. They have been proposed in many reports for detecting the DNA hybridization event, due to their high sensitivity, small dimensions, low cost, and compatibility with microfabrication technology.The immobilization of ssDNA at the electrode is the key step in the preparation of DNA biosensors. Many methods have been employed for the immobilization of DNA, including adsorption, self-assembly monolayer (SAM), covalent binding, blending and electropolymerization. Self-assembly monolayer and electropolymerization synthesize adsorption and covalent binding method. Immobilization of a single-stranded (ss) deoxyribonucleic acids (DNA) chain or an oligonucleotide of specific sequence on the electrode creates a biosensor that detects the DNA hybridization. Another type of device is a biosensor with immobilized double-stranded (ds) DNA detecting small molecules interacting with DNA. This kind of biosensor is supposed to be used for detecting harmful substances present, e.g., in the environment as well as in food and so on.The goal of the present study is to design and optimize new DNA immobilization...