DNA-Aptamer–Based Electrochemical Biosensors for the Detection of Thrombin

A biosensor is a self-contained embedded device that uses a biological detection component (such as antibodies, enzymes, natural receptors, aptamers, cells, etc.) that is kept in direct three-dimensional (3D) contact with a transduction component to give focused quantitative or semi-quantitative analytical information. Aptamer (synthetic ss-DNA or ss-RNA) has proved its excellent potential as a promising sensing element due to its enormous benefits in biosensor applications for detecting numerous analytes. There are various kinds of biosensors either based on bio-recognition components or signal transducing techniques, such as optical, electrochemical, and mass-based biosensors. Among them, DNA-aptamer electrochemical biosensors have demonstrated good potential in numerous analytes recognition, offering a wide variety of benefits. Incorporation of nanomaterials in electrochemical DNA-aptasensors further enhances their performance in terms of stability, rapidity, limit of detection, and sensitivity. Thrombin is an extremely specific serine protease applicable for anti-clotting therapeutics, playing a key role in hemostasis, leading to many pathologies. We examine in this chapter the various fundamental aspects of biosensors and their recent progress, with an emphasis on the most promising DNA-aptamer functionalized nanomaterials–based electrochemical biosensors for thrombin detection.