SPION size dependent effects on normal and cancer cells

Iron oxide nanoparticles have become widely used today in medical applications. In this study, we report a hyperthermia treatment with 10 and 100 nm naked and polyethylene glycol(PEG)-coated Super Paramagnetic Iron Oxide Nanoparticles (SPIONs) to normal and tumor cells in culture. Cells’ responses to nanoparticles were analyzed by cell viability assays (MTT and LDH) and transmission electron microscopy. Results indicate that even if 10 nm SPIONs have good magnetization saturation, the hyperthermia treatment is not effective due to the fact that cells do not endocytose them. 100 nm SPIONs are better engulfed by cells, and their hyperthermia effect is slightly increased. Macavei et al (PDF

Pharmacological Potential of Three Berberine-Containing Plant Extracts Obtained from <i>Berberis vulgaris</i> L., <i>Mahonia aquifolium</i> (Pursh) Nutt., and <i>Phellodendron amurense</i> Rupr

Three berberine-containing plant extracts were investigated for their pharmacological properties. The stems and leaves of Berberis vulgaris, Mahonia aquifolium, and Phellodendron amurense were characterized through scanning electron microscopy. The plant extracts obtained from fresh stem barks were further analyzed through high-performance liquid chromatography, revealing berberine concentrations, among berbamine and palmatine. The plant extracts were further tested for their anticancer potential against 2D and 3D human skin melanoma (A375) and lung adenocarcinoma (A549) cell lines. The concentrations at which 50% of the cells are affected was determined by the viability assay and it was shown that B. vulgaris, the plant extract with the highest berberine concentration, is the most efficient inhibitor (0.4% extract concentration for the 2D model and 3.8% for the 3D model). The membrane integrity and nitrate/nitrite concentration assays were consistent with the viability results and showed effective anticancer potential. For further investigations, the B. vulgaris extract was used to obtain silver nanoparticles, which were characterized through transmission electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. The formed nanoparticles have a uniform size distribution and are suited for future investigations in the field of biomedical applications, together with the B. vulgaris plant extract

Characterization of defect structures in nanoscaled W-doped TiO2 tested as supercapacitor electrode materials

In this work, Tungsten(W)-doped TiO 2 nanoparticles were synthesized using the sol–gel method and were used as electrode materials in supercapacitor applications. The structural and morphological properties of the prepared samples were analyzed by means of XRD, STEM, TEM, and XPS. The analysis of the defect centers was carried out using EPR spectroscopy. The electrochemical analysis of the assembled supercapacitor was done using cyclic voltammetry, galvanostatic cycling with potential limitation technique, potentiostatic electrochemical impedance spectroscopy, and voltage-holding experiments. All the presented samples showed paramagnetic defects in the EPR analysis, while 0.5% W-doped TiO 2 showed a maximum signal intensity. The supercapacitor performance from the synthesized electrode material showed highly encouraging results. The equivalent series resistance (Rs) value for all the designs showed values under “1 Ω ,” which reflects high conductivity. As the maximum EPR intensity comes from TiO 2 doped with 0.5% W, the supercapacitor performance of this sample was tested with a newly designed five-electrode system. This design showed superior performance compared to any other used designs with a specific capacitance of 25.5 F g- 1, with an energy density of 14.16 Wh kg- 1 at 302 kW kg- 1

In Vivo Distribution of Poly(ethylene glycol) Functionalized Iron Oxide Nanoclusters: An Ultrastructural Study

The in vivo distribution of 50 nm clusters of polyethylene glycol-conjugated superparamagnetic iron oxide nanoparticles (SPIONs-PEG) was conducted in this study. SPIONs-PEG were synthesized de novo, and their structure and paramagnetic behaviors were analyzed by specific methods (TEM, DLS, XRD, VSM). Wistar rats were treated with 10 mg Fe/kg body weight SPIONs-PEG and their organs and blood were examined at two intervals for short-term (15, 30, 60, 180 min) and long-term (6, 12, 24 h) exposure evaluation. Most exposed organs were investigated through light and transmission electron microscopy, and blood and urine samples were examined through fluorescence spectrophotometry. SPIONs-PEG clusters entered the bloodstream after intraperitoneal and intravenous administrations and ended up in the urine, with the highest clearance at 12 h. The skin and spleen were within normal histological parameters, while the liver, kidney, brain, and lungs showed signs of transient local anoxia or other transient pathological affections. This study shows that once internalized, the synthesized SPIONs-PEG disperse well through the bloodstream with minor to nil induced tissue damage, are biocompatible, have good clearance, and are suited for biomedical applications