The roles of green chemistry in nanotechnology and nanoscience fields are very significant in the synthesis of diverse nanomaterials. Herein, we report a green chemistry method for synthesized colloidal silver nanoparticles (Ag NPs) in polymeric media. The colloidal Ag NPs were synthesized in an aqueous solution using silver nitrate, polyethylene glycol (PEG), and β-D-glucose as a silver precursor, stabilizer, and reducing agent, respectively. The properties of synthesized colloidal Ag NPs were studied at different reaction times. The ultraviolet-visible spectra were in excellent agreement with the obtained nanostructure studies performed by transmission electron microscopy (TEM) and their size distributions. The Ag NPs were characterized by utilizing X-ray diffraction (XRD), zeta potential measurements and Fourier transform infrared (FT-IR). The use of green chemistry reagents, such as glucose, provides green and economic features to this work.

Silver nanoparticles (Ag-NPs) were synthesized into the interlamellar space of montmorillonite (MMT) by using the γ-irradiation technique in the absence of any reducing agent or heat treatment. Silver nitrate and γ-irradiation were used as the silver precursor and physical reducing agent in MMT as a solid support. The MMT was suspended in the aqueous AgNO 3 solution, and after the absorption of silver ions, Ag + was reduced using the γ-irradiation technique. The properties of Ag/MMT nanocomposites and the diameters of Ag-NPs were studied as a function of γ-irradiation doses. The interlamellar space limited particle growth (d-spacing [d s ] = 1.24-1.42 nm); powder X-ray diffraction and transmission electron microscopy (TEM) measurements showed the production of face-centered cubic Ag-NPs with a mean diameter of about 21.57-30.63 nm. Scanning electron microscopy images indicated that there were structure changes between the initial MMT and Ag/MMT nanocomposites under the increased doses of γ-irradiation. Furthermore, energy dispersive X-ray fluorescence spectra for the MMT and Ag/ MMT nanocomposites confirmed the presence of elemental compounds in MMT and Ag-NPs. The results from ultraviolet-visible spectroscopy and TEM demonstrated that increasing the γ-irradiation dose enhanced the concentration of Ag-NPs. In addition, the particle size of the Ag-NPs gradually increased from 1 to 20 kGy. When the γ-irradiation dose increased from 20 to 40 kGy, the particle diameters decreased suddenly as a result of the induced fragmentation of Ag-NPs. Thus, Fourier transform infrared spectroscopy suggested that the interactions between Ag-NPs with the surface of MMT were weak due to the presence of van der Waals interactions. The synthesized Ag/MMT suspension was found to be stable over a long period of time (ie, more than 3 months) without any sign of precipitation.

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In this study, we investigated the synthesis of silver nanoparticles using Peganum harmala water extract at ambient temperature. The Ag nanoparticles (AgNPs) were characterized by ultravioletvisible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). The average particle size of the silver nanoparticles was about 23 nm. Inhibitory activity of the synthesized AgNPs was tested against human pathogens like Escherichia coli and Staphylococcus aureus. The results indicated that the AgNPs showed moderate inhibitory actions, demonstrating its antibacterial value against pathogenic diseases. ARTICLE HISTORY

In this project, facile, rapid biosynthesis and characterization of silver-montmorillonite (MMT) nanocomposite is carried out at ambient temperature. Silver nanoparticles (Ag-NPs) were prepared by water extract of the plant [Satureja hortensis (L)] as the reducing agent and MMT as interlamellar space for controlling the size of Ag-NPs. MMT was sonicated in the aqueous AgNO 3 solution and Ag + ions were reduced to Ag° using water extract of Satureja hortensis (L). The nanocomposite was evaluated using ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). TEM study showed the formations of nanocomposite using water extract of Satureja hortensis L in the range of 4.88-26.70 nm and an average particles size of 15.79 nm. In addition, XRD studies indicated that the particles have a face centred cubic (FCC) structure. The nanocomposite showed antibacterial effects against bacteria.