Introduction to metal oxide-based biosensing

This chapter briefly introduces biosensors, mostly metal oxide-based biosensors, including their principles and essential components. Metal oxides (MOs), primarily nanoscopic MOs, have recently gained huge research importance owing to their effective surfaces for biomolecule immobilization, better conformation, and superior biological activities resulting in improved sensing characteristics. Nanophase MOs with unique optical, electrochemical properties, along with the required surface functionalities and electronic properties, offer fascinating bio platforms for the interaction of biorecognition elements with transducers for better signal intensification. Among these various biosensors, electrochemical biosensors have been most economical, miniaturized, and are profoundly being used for point-of-care applications. In this chapter, MO-based biosensors are discussed in detail. The electroanalytical characteristics of biosensors and materials used for the selectivity of biosensors are described, and advantages, challenges, and scope for the future in bionanosensors are summarized.