CHAPTER 12: Biological Materials

Nanoscience and nanotechnology (N&N) have aroused great interest in the past few decades due to their potential impact on several and different areas of knowledge, such as electronics, energy, and biomedicine. This technology allows for the manipulation of materials possessing very small size, with dimensions ranging from a few nanometers to less than 100 nanometers. Nanoparticles (NPs), especially metallic ones, have properties that are strongly dependent on size and morphology and are interesting for applications ranging from high-performance catalysts and excellent antimicrobial activity to biosensors and optics. Several methods of synthesis of metallic nanoparticles (MNPs) have been developed in order to control their size and shape, however the majority of them use substances that are potentially toxic and harmful to the environment. Currently, several studies seek the development of reliable, clean and eco-friendly experimental techniques for NP synthesis. An approach that has shown great potential is based on the biosynthesis of NPs using different biological components, such as plant derivatives (extract of leaves, fruits, and roots) and microorganisms (fungi, bacteria, yeast, etc.). The purpose of this chapter is, therefore, to present the current and reflect on the future perspectives of biological-based methods for MNP synthesis. Advantages and limitations of different branches of such an approach are herein discussed.