An overview on the green synthesis of nanoparticles and other nano-materials using enzymes and their potential applications

The applications of nanoparticles (NPs) and another nanomaterial (NM) are widely increasing in various fields including biomedical and clinical sciences. Conventional methods used for the synthesis of NM have several demerits like chemical procedures producing toxic materials and physical methods being costly and forming particles of non-uniform sizes. The use of such NM has prevented their applications in biomedical fields especially in clinical applications. In order to use NPs in clinical fields, there is a need to use reliable, nontoxic and eco-friendly methods for their synthesis. The use of eco-friendly and biological methods for the synthesis of NPs and other NM has attracted the attention of nanobiotechnologists due to synthesis of such particles by using nontoxic method. The enzymatic synthesis of NPs is highly specific as this procedure results in the formation of nontoxic materials of controlled shape, size and high stability. In this chapter an effort has been made to critically review recent developments in the area of biosynthesis of several types of NM by using enzymes of diverse groups such as oxidoreductases, transferases, hydrolases, lyases and ligases. The mechanisms of enzyme catalyzedsynthesis of NPs and the reaction conditions to control their shape, size, and stability of NPs have also been described. Numerous kinds of techniques employed for the identification and characterization of NM have been discussed. The biomedical and other applications of as-synthesized NM have also been mentioned in this article.