Biosilica Nanoparticles from Agricultural Waste and Their Applications

A variety of nanoparticles are currently transforming many aspects of human life and offering creative solutions for overcoming current issues in a sustainable way. In this context, silica nanoparticles (SiNPs) have lately become significant nanomaterials with wide-ranging applications. SiNPs are attractive for their use in a variety of industries, including biomedicine and environment clean-up, because of their variable and tuneable properties. Agricultural waste such as rice and wheat husk, sugarcane bagasse, corn cob, etc. are much explored for synthesis of nanoparticles through chemical methods but usage of biological means is very limited. Therefore, they have a lot of potential as one of the many low-cost and renewable resources being researched as a source of precursor materials for the synthesis of SiNPs. Creating nanosilica from agro-waste opens up new management and value-adding options for agricultural waste. Different conventional methods are in use to extract the bonded silica from agro-wastes, however, extraction mediated by microorganisms can make the process even more environmentally benign and hence has a lot of research potential. This chapter identifies different agricultural wastes that can be used to produce SiNPs as precursors and describes in detail how SiNPs are biologically extracted from agro-waste and a number of SiNP applications are also discussed.