User:Nisha Akash Yadav/sandbox

= Nanozymes =

Introduction
In recent years, nanotechnology has shown numerous revolutionary developments in the area of modern research. Nanotechnology deals with the materials that have at least one dimension in nanoscale (less than 100 nm). These materials are known as nanoparticles (NPs). NPs possess unique physicochemical properties which are associated with size range and surface charge of metal atoms. These properties make them an attractive material for therapeutic and diagnostic applications. NPs, which have a different physical and chemical property than their bulkier forms are continuously proving themselves as a future essential. Since the ancient time to till date these NPs are continuously growing and researchers have found out different types of materials from which they can synthesize NPs. NPs can be synthesized by various routes such as top down and bottom up which have subtypes like fabrication, chemical synthesis, laser ablation, chemical and physical vapour deposition and so on. NPs can be differentiated into metal, metal oxide, magnetic, and other organic NPs based on the type of core materials used for the NPs synthesis. NPs have a wide range of applications like, biomedical, energy generation, catalyst, and food and agriculture industry which depends on its synthesis routes and care materials. Various NPs such as gold (Au), silver (Ag), copper (Cu), cerium oxide (CeO2/Ce2O3), iron oxide (Fe2O3), organic NPs such as liposomes have shown a wide range of application in drug delivery, protecting agent, biosensing, nanozymes, diagnosis, prosthesis and implants.

In the biological system, a number of free radicals are generated as a result of oxygen metabolism and these radicals are highly unstable molecules which have a tendency to react with proteins, DNA/RNA, or other biomolecules of the body. Free radicals are the molecules that are produced as a by-product of normal metabolic reactions. They are highly unstable and have the capability to harm the biomolecules. They are necessary part of many cellular reactions but when their level exceeds, they can be hazardous. Naturally, antioxidants are produced in the biological system to control the level of free radicals but when there is imbalance between the level of free radicals produced and antioxidants generated, then a condition arises, which is known as oxidative stress. Reactive oxygen species (ROS) and Reactive nitrogen species (RNS) are two major types of free radicals generated in the living system. Since last decade, a number of metal oxide NPs (MONPs) such as iron oxide, cerium oxide, zirconium oxide, aluminium oxide, copper oxide etc. have the potential to scavenge these ROS species and behave much like natural antioxidants.

Advantages of nanozymes
The NPs which can behave like natural enzymes are known as nanozymes. Compared with natural enzymes, nanozymes are advantageous in several aspects:

1.    Low Cost: Nanozymes are much cheaper than natural enzymes.

2.    Robustness to harsh environments: Nanozymes can survive in harsh environmental conditions such as high temperature, pH etc.

3.    Easy for mass production: Nanozymes can easily be scaled up at high level as compared to natural enzymes.

4.    High stability: Nanozymes are comparatively more stable than natural enzymes even at room temperature.

5.    Long-term storage: Nanozymes can be stored for a long time.

6.    Size/composition dependent activity: Nanozymes show size and composition dependent activity and we can alter the properties of nanozymes as per our need.