deposition of hydroxyapatite on graphene nanosheets
Graphene nanosheets were effectively functionalized by deposition of hydroxyaptite through a facile chemical precipitation method. Prior to grafting of hydroxyapatite, chemically modified graphene nanosheets were obtained by the reduction of graphene oxide in presence of ethylenediamine. The resulting hydroxyapatite functionalized graphene nanosheets were characterized by attenuated total reflection IR spectroscopy, X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, X-ray energy dispersive spectroscopy, Raman spectroscopy and thermogravimetric analysis. These characterization techniques revealed the successful grafting of hydroxyapatite over well exfoliated graphene nanosheets without destroying their structure.
Gold-Based Magneto/Optical Nanostructures: Challenges for In Vivo Applications in Cancer Diagnostics and Therapy
Nanoparticles with gold shell and iron core have unique optical and magnetic properties which can be utilized for simultaneous detection and treatment strategies. Several nanoparticles have been synthesized and shown to mediate a variety of potential applications in biomedicine, including cancer molecular optical and magnetic resonance imaging, controlled drug delivery, and photothermal ablation therapy. However, to be effective, these nanoparticles must be delivered efficiently into their targets. In this review, we will provide an updated summary of the gold-shelled magnetic nanoparticles that have been synthesized, methods for characterization, and their potential for cancer diagnosis and treatment. We will also discuss the biological barriers that need to be overcome for the effective delivery of these nanoparticles. The desired nanoparticle characteristics needed to evade these biological barriers were also explained. Hopefully, this review will help researchers in designing nanoparticles by carefully choosing the optimum size, shape, surface charge, and surface coating.
Photocatalytic Degradation of Reactive Brilliant Blue X-BR in Aqueous Solution Using Quantum-sized ZnO
Quantum-sized ZnO was prepared using sol-gel method with Zinc acetate dehydrate (Zn(CH(3)COO)(2).2H(2)O) and lithium hydroxide monohydrate(LiOH.H(2)O) as raw material. The ZnO particles annealed at different temperature were characterized by means of X-ray diffraction (XRD), Infrared absorption spectroscopy (IR) and UV-Vis spectroscopy. The degradation rate of reactive brilliant blue X-BR in aqueous solution was used to evaluate the photocatalytic performance of the quantum-sized ZnO. The experimental results indicated that the photocatalytic property of the ZnO was excellent. The photocatalytic efficiency of quantum-sized ZnO was significantly influenced by the calcining heat. When calcined at 300(o)C, its size is 6.78 nm and the photocatalytic performance is the best. The degradation rate of reactive brilliant blue X-BR could exceed 90% in 15 min at 35(o)C, when the concentration of the quantum-sized ZnO was 0.35 mg/L.
Porous cobalt spheres for high temperature gradient magnetically assisted fluidized beds
Porous metallic cobalt spheres have been prepared as high temperature capable media for employment in gradient magnetically assisted fluidization and filtration technologies. Cobalt impregnated alginate beads are first formed by extrusion of an aqueous suspension of Co3O4 into a Co(II) chloride solution. The organic polymer is thermally decomposed yielding cobalt oxide spheres, followed by reduction to the metallic state, and densification. Cobalt beads have been produced with porosities ranging between 10 and 50%, depending upon sintering conditions. The product media have been characterized by scanning electron microscopy (SEM), nitrogen adsorption porosimetry, and vibrating sample magnetometry.