Properties, effects and chemical and biological method of synthesis of silver nanoparticles

The silver nanoparticles (AgNPs) have gained significant attention due to their remarkable properties. Due to the electrical and catalytic properties of silver nanoparticles it is greatly exploited commercially. However, silver nanoparticles adversely affect the environment and can have hazardous, detrimental toxic effects on mammals, non-mammals and plants. The properties of silver nanoparticles greatly depend on the synthesis process conditions such as process type, temperature, pH, concentration of precursor, reducing agents and capping agents used. In this review we have discussed the bottom-up approach which is categorized into chemical synthesis and green synthesis. The chemical synthesis is a conventional method which is used to synthesize silver nanoparticles. However, it does possess major disadvantages as compared to the green synthesis. The green synthesis has gained a significant interest among the researchers as an alternative route to effectively synthesize silver nanoparticles with varying morphology. Green synthesis methods such as viral-biotemplates synthesis using TMV has gained specific attention as it is used in the synthesis of 1D silver nanostructure. The advantages and disadvantages of bottom-up method of silver nanoparticle synthesis is also discussed.  This article also provides a critical review on the properties and effects of silver nanostructures.