In recent years, green synthesis of nanoparticles has been the cornerstone of development of nanotechnology and its applications, as it emphasizes on promoting environmental sustainability. The aim of the present study was to investigate the potential health benefits of the green-synthesized titanium nanoparticles (TiO2NPs). TiO2NPs were synthesized using titanium(iv) isopropoxide and lupin bean extract. The synthesized particles were characterized to assess the average particle size by dynamic light scattering, and X-ray diffraction method was used to study the crystalline nature. The average particle size recorded was 9.227 nm with a polydispersity index (PDI) of 0.382. The morphology of the particles was assessed by scanning electron microscope and transmission electron microscopy which showed varied shapes of the nanoparticles, uniform spherical and crystallite rod shaped. Further, the cytotoxic efficacy of the nanoparticles was assessed against the breast cancer (MCF-7) cell line using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromidefor (MTT) assay. The antibacterial activity of the nanoparticles was evaluated against clinical pathogens via the disc diffusion assay. The key findings showed that the TiO2NPs exhibited potent cytotoxicity against the MCF-7 cell line with an IC50 of 41.1 µg. It also showed profound antibacterial activity. Thus, the synthesized nanoparticles could have potential biomedical applications owing to their therapeutic efficacy.

Synthesis of nanostructures using green chemistry has been popular owing to the exciting properties and innovative applications of these nanostructures. Novel, cost-effective, and eco-friendly gold nanoparticles (Au NPs) were synthesized using a mix of Olea europaea (OE) fruit extract and Acacia nilotica (AN) husk extract. The synthesized Au NPs were characterized by UV-visible spectroscopy, and the average NP size (44.96 nm) was measured by a Zetasizer. A more detailed characterization was performed using Fourier transform infrared spectroscopy, scanning, and transmission electron microscopy and electron microscopy with energy dispersive spectroscopy. The cytotoxicity of the synthesized OEAN Au NPs was evaluated using an MTT assay on breast (MCF-7), colon (TCT-116), and hepatocellular (HCepG-2) carcinoma cells. The antibacterial activity of the synthesized OEAN Au NPs was investigated using a disc diffusion method. The synthesized Au NPs exhibited moderate antibacterial activity against the bacterial strains used and profound anticancer activity against different cell lines used. (C) 2019 Elsevier B.V. All rights reserved.

A novel, nontoxic, simple, cost-effective and ecofriendly technique was used to synthesize green silver nanoparticles (AgNPs). The AgNPs were synthesized using orange peel extract as a reducing agent for silver nitrate salt (AgNO3). The particle size distribution of AgNPs was determined by Dynamic Light Scattering (DLS). The average size of silver nanoparticles was 98.43 nm. The stable dispersion of silver nanoparticles was added slowly to polystyrene solution in toluene maintaining the temperature at 70°C. The AgNPs/polystyrene (PS) nanocomposite solution was cast in a petri dish. The silver nanoparticles encapsulated within polymer chains were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) equipped with Energy Dispersive Spectroscopy (EDS) in addition to Transmission Electron Microscopy (TEM). The green AgNPs/PS nanocomposite film exhibited antimicrobial activity against Gram-negative bacteria Escherichia coli, Klebsiella pneumoniae and Salmonella, and Gram-positive bacteria Staphylococcus aureus. Thus, the key findings of the work include the use of a safe and simple AgNPs/PS nanocomposite which had a marked antibacterial activity which has a potential application in food packaging.

Purpose: To develop a novel approach to green synthesis of nano-polymer porous gold oxide nanoparticles, and examine the effects of the temperatures on their surface.Methods: Green synthesis of nano-polymer porous gold oxide nanoparticles (GONPs) using cetyle trimethylammonium bromide (CTAB) surfactant with a mixture of Olea europaea fruit and Acacia Nilotica extracts, was performed using sol-gel method. The nanoporous particles were characterized by UV (ultraviolet (UV) visible spectroscopy and dynamic light scattering (DLS) while a zetasizer was applied to determine their average particle size. Their surface morphology and shape were assessed by transmission electron microscopy (TEM) and scanning election microscopy (SEM) while surface area was measured using nitrogen gas adsorption method.Results: TEM and SEM images showed a smooth, cylindrical or spherical, and cluster shapes, and porous surface morphology. Increase in calcination temperature resulted in increase in surface area and pore volume of nanoparticles. This feature yielded GONPs that were unique with a high surface area of 146.706 m(2)/g.Conclusion: The approach used in this study constitutes a new and rapid green synthesis of porous nanoparticles of gold oxide under simple conditions. Furthermore, increase in GONPs surface area is enhanced by increase in calcination temperature.

Synthesis of nanoparticles by green methods with antibacterial properties is of great researchers' concern in the explored of new pharmaceutical and biomedical products. In this study, we synthesized a new product of nanosized particles of silver, non-toxic economy, clean, and conservator for energy. An environmentally friendly route is used for synthesizing silver nanoparticles (AgNPs) using an orange peel extract as both reducing and stabilizing agent at room temperature. The synthesized NPs were characterized using ultraviolet (UV)-Vis spectrophotometer, Zitasizer which measures the average size of the particles at about 91 nm, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) equipped with the energy dispersive spectroscopy (EDS) and characterization using Transmission electron microscopy (TEM). The results confirmed that the orange peel extract is a very good bioreductant for the synthesis of Ag NPs and we investigated the synthesized nanoparticles as an antibacterial which showed that the biogenic synthesized AgNPs exhibit inhibition, and had significant antibacterial against both gram-positive and gram-negative bacterial strains. Key words: Silver nanoparticles, biogenic synthesis, orange peel, anti bacterial, gram-positive, gram-negative bacteria streamers.