Peroxidase-Like Activity of Metal Nanoparticles for Biomedical Applications

Nanoparticles are versatile proponents in modern-day research. Upon scaling down to the nano-range, materials exhibit a host of interesting properties, for use in imaging, sensing, and therapeutic approaches. Enzymes as biocatalysts require optimal thermodynamic conditions for maximal activity. Their purification protocols are both labor intensive and uneconomical, paving the need for development of simpler alternatives. Metal nanoparticles act as redox enzymes due to the electron exchange escalated by their superficial atoms. Also, monolayer-protected metal nanoparticles electrostatically interact with different substrates, promoting catalysis. This enables their use in industries, in detection of environmental pollution, and in biomedical applications and other clinical approaches. Peroxidases are an essential family of enzymes, capable of removing harmful metabolic by-products from the cellular environment and involved in the maintenance of cellular defense and integrity. This chapter lays its focus on the peroxidase-like activity of metal nanoparticles and their role in development of biosensors and immunoassays and detection of tumor cells while discussing its present catalytic limitations and future outlook.