Effects of Redox Couple on the Response of Polypyrrole-Based Electrochemical DNA Sensors

Much research-to-date exists to create sensitive and selective DNA sensors. A variety of approaches are adopted, including those involving polypyrrole and electrical impedance spectroscopy. Combined these are able to sense as well as aptly transduce signals. Many such sensors employ ferri/ferrocyanide to exhibit surface hybridization. This redox reporter, though with merits, can prove disadvantageous. To this end, a comparative study was performed with the redox reporter hydroquinone. For comparison purposes ferri/ferrocyanide indicated greater sensitivity, suggested to arise from inherent charge. Conversely, with hydroquinone steric hindrance is the main influencing factor. Such a study aims to guide design of analogous sensors.