This study uses silicone monomer, DMA, crosslinking agent EGDMA, and initiator AIBN as a basic combination to prepare hydrogel lenses using fluorine-based perfluoro polyether and iron oxide and zinc oxide nanoparticles as additives. After manufacturing the lens using iron oxide nanoparticles and zinc oxide nanoparticles, the optical, physical properties, and polymerization stability are evaluated to investigate the possibility of application as a functional hydrogel lens material. As a result of this experiment, it is found that the addition of the wetting material containing fluorine changes the surface energy of the produced hydrogel lens, thereby improving the wettability. Also, the addition of iron oxide and zinc oxide nanoparticles satisfies the basic hydrogel ophthalmic lens properties and slightly increases the UV blocking performance; it also increases the tensile strength by improving the durability of the hydrogel lens. The polymerization stability of the nanoparticles evaluated through the eluate test is found to be excellent. Therefore, it is judged that these materials can be used in various conditions as high functional hydrogel lens material.
We prepare ZnO nanoparticles by environmentally friendly synthesis using Cyathea nilgiriensis leaf extract. Various phytochemical constituents are identified through the assessment of ethanolic extract of plant Cyathea nilgiriensis holttum by GC-MS analysis. The formation of ZnO nanoparticles is confirmed by FT-IR, XRD, SEM-EDX, TEM, SAED and PSA analysis. TEM observation reveals that the biosynthesized ZnO nanopowder has a hexagonal structure. The calculated average crystallite size from the high intense plane of (1 0 1) is 29.11 nm. The particle size, determined by TEM analysis, is in good agreement with that obtained by XRD analysis. We confirm the formation of biomolecules in plant extract by FT-IR analysis and propose a possible formation mechanism of ZnO nanoparticles. Disc diffusion method is used for the analyses of antimicrobial activity of ZnO nanoparticles. The synthesized ZnO nanoparticles exhibit antimicrobial effect in disc diffusion experiments. The biosynthesized ZnO nanoparticles display good antibacterial performance against B. subtilis (Gram-positive bacteria) and K. pneumonia (Gram-negative bacteria). Bio-synthesized nanoparticles using green method are found to possess good antimicrobial performance.
Background : For the green approach of nanoparticles synthesizing, plant based technology has been considered as cost-effective and eco-friendly mass production. The oriental medicinal crop, Kalopanax septemlobus (Thunb.) Koidz. (Korean name: 음나무), the deciduous tree and a family of Araliaceae. Endemic tree of Asian countries, K. septemlobus being used for the treatment of various diseases. Phytochemicals of K. septemlobus such as polyphenols has highly probability of reducing agent for biosynthesizing nanoparticles.
Methods and Results : In this study, we applied K. septemlobus ZnO nanoparticles (Ks-ZnO NPs) with procedures including green approach one-pot synthesis. For the characterization of nanoparticles, UV–Vis, FTIR, XRD, SEM and TEM were used. The formation of ZnO nanoparticles, the aurface plasmon resonance were observed at 372 ㎚ in UV-Vis spectroscopy. The presence of functional groups which as a capping agent and formation of ZnO nanoparticles were confirmed in FTIR result. The crystallization and morphology showed by XRD, TEM and SEM respectively. The photocatalytic activity of ZnO nanoparticles, was determined using Methylene blue (MB) dye degradation under UV irradiation (365 ㎚) which resulted rate constant is (−k) 0.1215 with 97.5% of degradation in 30 min.
Conclusion : The result shows that phytochemicals in K. septemlobus extract have a potential as a reducing agent to form ZnO nanoparticles. The ZnO NPs are capable to degrade MB with in brief time.
Background : Among medicinal plant sources, Abeliophyllum distichum is widely used in traditional Korean medicine. we report on the synthesis of nanostructured zinc oxide particles by both chemical and biological method. Highly stable and spherical zinc oxide nanoparticles are produced by using zinc nitrate and Abeliophyllum distichum leaf extract.
Methods and Results : Zinc oxide (Ad-ZnONPs) nanoparticles synthesized from Abeliophyllum distichum at room temperature by aqueous extract of dried leaf and stem. The plant endemic in Korea alone and it is a monotypic flowering plant genus of olive family, Oleaceae. Catalytic and toxicity effect against human keratinocyte and adenocarcninomic human alveoloar. Ultra violet visible (UV-Vis) spectroscopy, field emission transmission electron microscopy (FE-TEM), energy-dispersive X-ray (EDX) spectroscopy, elemental mapping, X-Ray powder diffraction (XRD), selected area electron diffraction (SAED) and Fourier transform infrared (FTIR) spectroscopy were engaged to illustrate the biosynthesized nanoparticles. The Zn-AdNPs has the ability in catalytic action and the cytotoxicity agent against different cell lines as investigated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium bromide (MTT) assay
Conclusion : The present studies reveals that facile approaching the biological synthesis of zinc oxide nanoparticles by using the A. distichum leaf and stem extract, which is revealed that recyclable method. The method is well suited for the green synthesis and dual function molecule as reducing agent and stabilizing agent for synthesis of nanoparticles. The nanoparticles also showing promising biological activities.