Many workers have paid more attention to eco-friendly mesoporous silica silver nanoparticles featuring smaller particle sizes to enhance their remarkable antimicrobial properties. A simple chemical method was developed for synthesize high valence silver nanoparticles immobilized on the mesoporoussilica nanomaterial, which showed strong antibacterial activity. Chemical reduction of silver ion has been regarded in the present work, and a reducing agent , such as hydrazine was used to promote the reduction of the silver ionprecursor. The average particle size of the synthesized mesoporous silica-silver nanoparticles (Ag/NH 2-KIT-6(x)) with different concentrations of Ag (3.2 and 7.1%) calculated from Scherrer's equation for (1 1 1)plane were 8 and 6.5 nm respectively. The synthesized materials were characterized using X-Ray diffraction (XRD), FTIR spectra, X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM), which revealed the mesoporous silica nanoparticles. Antibacterial activities of mesoporous silver nanoparticles against Gramnegative Pseudomonas aeruginosa(ATCC 9027) and Gram-positive Staphylococcus aureus(ATCC 43300) were found to be increased with the increasing of Ag concentration in the Ag/NH 2-KIT-6(x). The maximum inhibition zone diameter when the concentration 7.1 % was used obtained against P. aeruginosaand S. aureuswith diameters of 32 and 30 mm respectively. The antimicrobial activity of mesoporousAg/NH 2-KIT-6(x) was evaluated also using the MIC&MBC tests. The surface structures of both the untreated and the treated bacterial cells were examined by the aid of TEM. The treated bacterial cells were significantly changed, and major damage was observed in the outer cell membrane. In conclusion the use of AgNPs as antibacterialagentwasfoundtobetoxicagainstpathogenicbacteriaandconsidered

Silver nanoparticles have shown success in many applications, especially in the field of biochemistry, by controlling the shape and size of these nanoparticles, which had a significant impact on the diversity of their antimicrobial properties. Many different shapes and sizes of silver nanoparticles can be prepared by various techniques, the most important of which is the use of capping agents, where the role of capping agents is not limited to controlling both sizes and shape only but extends to the stability of nanoparticles nanostructures. In addition, the type of capping agent has an influential role in the surface efficiency of the formed silver nanoparticles. However, multiple concerns have been raised regarding the environmental safety and human health impacts of the use of chemically manufactured capping agents. This review included the manufacture of silver nanoparticles using aqueous extract of some plants, flowers, or fruits, and their applicability and activity in various fields such as antioxidants and antibacterials were examined. Also, some of the most common and popular chemical and physical methodologies are initially described, and the advantages and disadvantages of using these methods to prepare silver nanoparticles are considered. Green synthesis methodologies have been discussed in detail with emphasis on their benefits and applications. Much of the recent literature related to the use of plant extracts have been addressed, and the effects of basic reaction parameters, such as temperature, pH, precursor, and extract concentration, on silver nanostructure size and morphology have been reported. Moreover, current challenges related to the green synthesis of silver nanostructures and future directions have been identified. In summary, the review aims to demonstrate the true potential of green nanotechnology towards the synthesis of silver nanostructures in various morphology and the possibility of moving away from current chemical techniques towards more environmentally friendly, less hazardous, simpler, and high efficient material as antimicrobial activity and Anti-oxidant.