Content area
Full Text
Abstract:
There is an increasing commercial demand for nanoparticles due to their wide applicability in various areas such as electronics, catalysis, chemistry, energy, and medicine. Metallic nanoparticles are traditionally synthesized by wet chemical techniques, where the chemicals used are quite often toxic and flammable. In this work, we describe a cost effective and environment friendly technique for green synthesis of silver nanoparticles from 1mM AgNO3 solution through the Methanolic extract of Adhatoda vasica as reducing as well as capping agent. Nanoparticles were characterized using UV-Vis absorption spectrophotometry, FTIR and SEM. SEM analysis showed the average particle size of 15-20nm as well as spherical to oval in shape. The synthesized nanoparticles show high DPPD free radical scavenging activity and reducing power activity. Further these biologically synthesized nanoparticles were found to be an anti diabetic agent and highly toxic against different human pathogens.
Keywords: Adhatoda vasica, Green synthesis, nanoparticles, SEM, Biological activities
Introduction:
Nanotechnology is an enabling technology that deals with structures ranging from approximately 1_100nm in at least one dimension (British Standards Institute [BSI] 2007) (1). The nano size results in specific physicochemical characteristics that may differ from those of the bulk substance or particles of larger size. This effect is mainly attributed to high surface area to volume ratio, which potentially results in high reactivity. Because of these specific characteristics the use of substances in nano form may have advantages over the use of bulk chemicals.
Among the noble metals (e.g., Ag, Pt, Au and Pd), silver (Ag) is the metal of choice for potential applications in the field of biological systems, living organisms and medicine (2). Due to their exclusive properties, silver nanoparticles (Ag-NPs) may have several applications, such as catalysts in chemical reactions (3), electrical batteries and in spectrally selective coatings for absorption of solar energy (4,5), as optical elements (6), pharmaceutical components and in chemical sensing and biosensing (7,8).
Various strategies are employed for synthesis of silver nanoparticles (9). Nanoparticles are synthesized by reduction in solutions (10), thermal decomposition of silver compounds (11), microwave assisted synthesis (12), Laser mediated synthesis (13) and biological reduction method. All these methods of synthesis of nano particles involves the usage of hazardous chemicals, cost effective and high laboratory resources are required and are polluting the...