11 - Metal oxide nanoparticles in biomedical applications

Abstract

Nanotechnology has achieved tremendous advancement in the past and continued to become an important method that creates useful materials with designed features. Application of nanotechnology in the synthesis of metal oxides has provided a new set of materials in nano sizes with unique features. These metal oxide nanoparticles (NPs) exhibit distinct physical and chemical properties due to their smaller size than their bulk-sized counterparts. The unique physicochemical properties of metal oxide NPs make it possible to create a wide variety of new biomedical applications. Examples of these metal oxide NPs are titania (TiO2), zinc oxide (ZnO), iron oxides (Fe2O3 and Fe3O4), and ceria (CeO2). Most of these materials are biocompatible and safe to be used in human. On accounts of their unique properties, they are used for numerous biomedical applications such as diagnostic agents, drug delivery, and medical implants. For example, titania is used for medical implants because of its biocompatible surface for cell attachment and proliferation. The low toxicity and biodegradability of zinc oxide NP have allowed it to be used in drug delivery and biosensing. Iron oxides, particularly superparamagnetic iron oxide NPs, are biodegradable and can be cleared from the human body via the iron metabolism pathways. They are suitable for magnetic resonance imaging, targeted drug delivery, and hyperthermia therapy. This chapter covers the recent advances and biomedical applications of metal oxide NPs by taking into account of their advantages, limitations, as well as toxicity. An overview of the metal oxide NPs in biomedical fields is presented with examples. We hope this chapter will serve as a useful reference for readers.