Peptide-Based Electrochemical Nanobiosensors for Clinical Diagnosis

The selectivity of a biosensor toward its target analyte is highly dependent on the biorecognition element used in the sensing matrix. A carefully designed peptide can be an alternative to an antibody, with major advantages such as more tolerance toward environmental conditions, tunable sequence to detect a wide variety of targets, and cost-effective solid-phase synthesis suitable for large-scale sensor production. Especially the electrochemical peptide-based biosensors have generated a lot of interest due to their sensitivity, selectivity, and quick response time for clinical diagnosis. The possibility of miniaturization of electrochemical devices also adds to its popularity for on-site diagnosis. In this chapter, we discuss the role of peptides as a biorecognition element in recently developed sensors for clinical diagnosis. The use of nanomaterials in sensor matrix development, surface engineering strategies for peptide immobilization and antifouling effect, signal amplification strategies, and the long-term stability of the developed sensors is critically assessed.