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As an alternative way to separation of biological molecules, silica coated magnetite ore particles were prepared through two step synthetic method including ball milling of iron ore powder followed by silica coating with Stöber method. As synthesized silica coated magnetic ore particles were composed mainly of magnetite and other accompanying minerals such as hematite and Al 2 O 3, ZrO 2. The particles were irregular in shape, with average size of 0.4±0.3 µm as demonstrated with SEM. Field dependent magnetization showed that silica-coated magnetite ore particles are soft ferromagnet with coercivity of 320Oe and remanent magnetization of 2.26 emu/g. Using these particles, genomic DNA was successfully separated from E. coli with sufficient yield and purity comparable to those obtained with a commercial magnetic separation kit, demonstrating their potential for bioseparation from diverse biological sources.
Copper-doped ZnO nanoparticles with a dopant concentration varying from 1–7 mol% were synthesized and their structural, magnetic, and photocatalytic properties were studied using XRD, TEM, SQUID magnetometry, EPR, UV-vis spectroscopy, and first-principles methods within the framework of density functional theory (DFT). Structural analysis indicated highly crystalline Cu-doped ZnO nanoparticles with a hexagonal wurtzite structure, irrespective of the dopant concentration. EDX and EPR studies indicated the incorporation of doped Cu2+ ions in the host ZnO lattice. The photocatalytic activities of the Cu-doped ZnO nanoparticles investigated through the degradation of methylene blue demonstrated an enhancement in photocatalytic activity as the degradation rate changed from 9.89 × 10−4 M min−1 to 4.98 × 10−2 M min−1. By the first-principles method, our results indicated that the Cu(3d) orbital was strongly hybridized with the O(2p) state below the valence band maximum (VBM) due to covalent bonding, and the ground states of the Cu-doped ZnO is favorable for the ferromagnetic state by the asymmetry of majority and minority states due to the presence of unpaired electron.
In this work transition metal copper (Cu) doped Zn1-xCuxO nanoparticles were synthesized by different doping concentration of Cu (x=1, 3, 5 and 7M %) through surfactant free benzyl alcohol route method in which zinc acetate, zinc acetylacetonate and copper acetate were selected as precursors. Crystal and structural analysis of all synthesized nanoparticles were determined by XRD and FT-IR. The XRD analysis demonstrated aff reflection peals with hexagonal wurtzite structure. The morphology and elemental analysis determined by TEM-EDX, TEM/STEM. Photocatalytic and antibacterial activity were studied by effectiveness of doping concentration. The methylene blue (MB) dye was used to investigate the photocatalytic experiment. 5M% Cu doped ZnO particles were showed high degradation efficiency. The antibacterial activity was tested in gram negative bacteria, E.Coli and gram positive S. Aureus dilution method. After the doping significant antibacterial inhibition founded from 7M% Cu doped ZnO NPs for 98.9% and 97.4% for E. coli and S. aureus, respectively. Keywords: Zinc oxide nanoparticles, Rhodamine 6G, photocatalytic activity, photo degradation, antibacterial activity, Escherichia Coli, Sataphylcoccus Aureus. Acknowledgements: This work is supported by the Asian Research Center Project (2018-3573).
Colloidal dispersions of spherical silver nanoparticles (AgNPs) have been synthesized by a citrate reduction method in which sodium citrate is utilized as both of reducing and stabilizing agents. Catalytic properties of as-synthesized AgNPs were examined using the reduction of 2,4-dinitrophenol (2,4-DNP) by sodium-borohydride. Experimental results revealed that the citrate-stabilized AgNPs is a very efficient catalysts for the degradation of 2,4-DNP.
