OICC Press Journal of Nanostructure in Chemistry 2193-8865 3 1 (December 2013) 2013 04 08 Green synthesis of densely dispersed and stable silver nanoparticles using myrrh extract and evaluation of their antibacterial activity 10.1186/2193-8865-3-8 EN Ibrahim M El-Sherbiny Zewail University, Zewail City of Science and Technology, Giza, 12588, EG Chemistry Department, Faculty of Science, Mansoura University, Mansoura, ET-35516, EG Ehab Salih Biological Advanced Materials, Physics Department, Faculty of Science, Mansoura University, Mansoura, ET-35516, EG Fikry M Reicha Biological Advanced Materials, Physics Department, Faculty of Science, Mansoura University, Mansoura, ET-35516, EG Journal Article 2013 04 08 Abstract In the present study, green synthesis of densely dispersed and stable silver nanoparticles (Ag NPs) using myrrh extract as green-reducing and stabilizing agent was investigated. The Ag NPs were synthesized by exposing a mixture of AgNO 3 and myrrh extract to UV irradiation for different time intervals. The effects of parameters such as concentration of AgNO 3 and reaction time onto the physicochemical characteristics of the developed Ag NPs were studied. Formation of the Ag NPs was noted upon changing the solution color from pale yellow into brown and was confirmed by the appearance of surface plasmon resonance peaks at about 445 nm. The resulting Ag NPs were characterized by UV-vis spectrophotometry, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The developed NPs demonstrated a relatively high antibacterial activity against Bacillus thuringiensis and Pseudomonas aeruginosa bacteria as compared to that of myrrh extract. The antibacterial activity increased with increasing the Ag NP concentration.