Sobhan Mortazavi-Derazkola - Pharmaceutical Sciences Research Center, Hemoglobinopathy Institute and Department of Medicinal Chemistry, School of Pharmacy, Mazandaran University of Medical Science, Sari, Iran.
Mina Shirzadi - Student Research Committee, Department of Medicinal Chemistry, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
Mohammad Ali Ebrahimzadeh - Pharmaceutical Sciences Research Center, Hemoglobinopathy Institute and Department of Medicinal Chemistry, School of Pharmacy, Mazandaran University of Medical Science, Sari, Iran.

Background and Objective: Nanotechnology is a field of science with vast potential in medicine. They exhibit a wide range of properties, including optical, electrical, catalytic, magnetic and biological activity which is different from that of their bulk materials. Silver nanoparticles are one of these materials with the unique properties. The most vital applications of the silver nanoparticles, in the field of medicine are using these nanoparticles as antibacterial agent. The lethal activity of nanoparticles (such as Ag nanoparticles) against broad spectrum of gram-positive bacteria, gram-negative bacteria can lead to advances in medical science. Materials and Methods: Silver nanoparticles with enhanced antibacterial activity have been synthesized through facile and rapid co-precipitation method in presence of Crataegus microphylla extract as a green reducing agent. The morphological and structural of the as-prepared nanoparticles were specified by FE-SEM, XRD, EDS, FT-IR and TEM analysis. Then, the antibacterial activity of the nanoparticles was investigated using different bacterial strains, including Staphylococcus aureus, Enterococcus, Pseudomonas aeruginosa and Acinetobacter by minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods. Findings: FE-SEM images showed the spherical nature of nanoparticles with the size ranging from 20-30 nm. So, due to the FT-IR spectrum, XRD pattern and FE-SEM images of the samples was revealed that silver nanoparticles were successfully synthesized. Crataegus microphylla based silver nanoparticles exhibited improved antibacterial activity against both gram-positive and negative strains. Conclusion: The aim of this work was green synthesis and characterization of silver nanoparticles through the co-precipitation method and in presence of Crataegus microphylla extract. Stability, smaller size and less aggregation were some of the features of as-synthesized nanoparticles. Further, these synthesized nanoparticles have high antibacterial activity.

Silver Nanoparticles; Green synthesis; Antibacterial