Biosynthesis of silver nanoparticles using Lawsonia inermis and their biomedical application.

Developing biosynthesis of silver nanoparticles (Ag-NPs) using plant extract is an environmentally friendly method to reduce the use of harmful chemical substances. The green synthesis of Ag-NPs by Lawsonia inermis extract and its cellular toxicity and the antimicrobial effect was studied. The physical and chemical properties of synthesised Ag-NPs were investigated using UV-visible spectroscopy, infrared spectroscopy, X-ray diffraction (XRD), scanning, and transmission electron microscopy. The average size of Ag-NPs was 40 nm. The XRD result shows peaks at 2θ = 38.07°, 44.26°, 64.43°, and 77.35° are related to the FCC structure of Ag-NPs. Cytotoxicity of synthesised nanoparticles was evaluated by MTT toxicity test on breast cancer MCF7 cell line. Observations showed that the effect of cytotoxicity of nanoparticles on the studied cell line depended on concentration and time. The obtained IC50 was considered for cells at a dose of 250 µg/ml. Growth and survival rates decreased exponentially with the dose. Antimicrobial properties of Ag-NPs synthesised with extract were investigated against Escherichia coli, Salmonella typhimurium, Bacillus cereus, and Staphylococcus aureus to calculate the minimum inhibitory concentration and the minimum bactericidal concentration of (MBC). The results showed that the synthesised Ag-NPs and the plant extract have antimicrobial properties. The lowest concentration of Ag-NPs that can inhibit the growth of bacterial strains was 25 µg/ml.

Nickel-Doped Cerium Oxide Nanoparticles: Green Synthesis Using Stevia and Protective Effect against Harmful Ultraviolet Rays.

Nanoparticles of cerium oxide CeO2 are important nanomaterials with remarkable properties for use in both industrial and non-industrial fields. In a general way, doping of oxide nanometric with transition metals improves the properties of nanoparticles. In this study, nickel- doped cerium oxide nanoparticles were synthesized from Stevia rebaudiana extract. Both doped and non-doped nanoparticles were characterized by X-ray diffraction, Field Emission Scanning Electron Microscopy, Energy Dispersive X-ray, Raman spectroscopy, and Vibrating-Sample Magnetometry analysis. According to X-ray diffraction, Raman and Energy Dispersive X-ray crystalline and single phase of CeO2 and Ni doped CeO2 nanoparticles exhibiting fluorite structure with F2g mode were synthesized. Field Emission Scanning Electron Microscopy shows that CeO2 and Ni doped nanoparticles have spherical shape and sizes ranging of 8 to 10 nm. Ni doping of CeO2 results in an increasing of magnetic properties. The enhancement of ultraviolet protector character via Ni doping of CeO2 is also discussed.

Leishmanicidal Activity of Biogenic Fe3O4 Nanoparticles.

Abstract: Due to the multiplicity of useful applications of metal oxide nanoparticles (ONPs) in medicine are growing exponentially, in this study, Fe3O4 (iron oxide) nanoparticles (IONPs) were biosynthesized using Rosemary to evaluate the leishmanicidal efficiency of green synthesized IONPs. This is the first report of the leishmanicidal efficiency of green synthesized IONPs against Leishmania major. The resulting biosynthesized IONPs were characterized by ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR). The leishmanicidal activity of IONPS was studied via 3-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results showed the fabrication of the spherical shape of monodisperse IONPs with a size 4 ± 2 nm. The UV-visible spectrophotometer absorption peak was at 334 nm. The leishmanicidal activity of biogenic iron oxide nanoparticles against Leishmania major (promastigote) was also studied. The IC50 of IONPs was 350 µg/mL. In this report, IONPs were synthesized via a green method. IONPs are mainly spherical and homogeneous, with an average size of about 4 nm, and were synthesized here using an eco-friendly, simple, and inexpensive method.