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We constructed the transferred ZnO biosensor and the grown ZnO biosensor by two different nano-ZnO immobilization approaches. And the influence of different assembly processes on the biosensor performance has been systematically investigated and compared. An enhanced sensitivity of the grown ZnO biosensor is found to be 52% higher than that of the transferred ZnO biosensor. Correspondingly, the other properties are also better in the grown ZnO biosensor, including the response time, the detection limit and the linear range. These results are well consistent with the fact that more glucose oxidase is immobilized on the well-aligned ZnO arrays, which have higher specific surface area and more direct electron communication path, in the grown sensor than the randomly distributed and stacked ZnO nanorods in the transferred sensor. The nano-ZnO grown directly has been demonstrated more desirable for enzymatic immobilization and signal transduction in the high performance biosensors., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Abstract Here we demonstrate a simple, rapid for the controlled synthesis of core-shell structural graphite coated TiO 2 nanoparticle (TiO 2 @G), which are directly prepared by detonation chemical decomposition of the gas-liquid mixture of CH 4 , O 2 , C 6 H 6 and TiCl 4 in milliseconds. Various techniques, including XPS, TEM, XRD and Raman were employed to investigate the products. It is found that the sphere, good disperse mixed crystal TiO 2 nanoparticles with crystal size of 10–30 nm were coated with thick graphite layers. Based on Zeldovich Neuman-Doring (ZND) model, the detonation synthesis mechanism of core-shell structure TiO 2 @G is discussed. This rapid synthesis method can be extended to the preparation of other core-shell materials. Graphical abstract Schematic diagram of TiO 2 @G nanoparticles growth. Unlabelled Image Highlights • Core-shell structure TiO 2 @G was prepared by a gas-liquid detonation methods. • The influence of carbon-free, carbon-low and carbon-rich environment on the coating structure was discussed. • The growth mechanism of the TiO 2 @G was discussed using ZND model. [ABSTRACT FROM AUTHOR]

Carbon-coated copper (Cu@C) nanoparticles with a core-shell structure were prepared by detonation decomposition of energetic Cu ion doped sol-gel explosive precursors. The composite nanoparticles were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), high resolution TEM, energy dispersive X-ray spectroscopy, and Raman spectroscopy, respectively. The results indicate that the as-obtained core-shell structure Cu@C nanoparticles are with diameter about 10-40 nm. The composite nanoparticles are composed of face-centered cubic-Cu and the amorphous/graphitic carbon coating shells. The thermal stability of the obtained samples was studied by a difference scanning calorimetry-thermogravimetric analyzer. By varying the composition of initial mixtures that contain Cu ion explosive precursors, the different size and chemical composition of composite nanoparticles are shown in this study. The growth mechanism of Cu@C was also briefly discussed. [ABSTRACT FROM AUTHOR]

Abstract: The nickel-based nanoparticles such as nickel oxide, carbon coated nickel, carbon coated nickel carbide and their mixtures were synthesized by systematically varying the component of explosive precursors and technological parameters. The features of the as-obtained nanoparticles were characterized with TEM, HRTEM, EDX, XRD and XRF. The data from these optimally designed experimental can govern the different types of nickel-based nanoparticles. The formation mechanism during the detonation process were also discussed and analyzed. [Copyright &y& Elsevier]

Abstract: Carbon-encapsulated iron-based nanoparticles with a core–shell structure were produced by detonation decomposition of explosive mixture precursors containing iron ion components. The size and magnetic properties of the as-prepared composite particles were revealed by X-ray powder diffraction, transmission electron microscopy and magnetic measurements. Results showed that the different sizes of the iron-based nanocrystal core and the thickness of the carbon shell could be yielded by adjusting the component materials of the explosive precursors during the course of these detonation chemical reactions. The composite particles had a body-centered cubic iron or iron carbide core with a coating of graphitic or amorphous carbon layers. Magnetic measurements indicated these composite nanoparticles were magnetic at the room temperature, with some variation in the values of saturation magnetization, remanences and coercive forces that depend on the size and grain composition. [ABSTRACT FROM AUTHOR]

A gas phase reaction was proposed for the production of high dispersity polymorphic titanium oxide (TiO 2 ) nanoparticles in a closed detonation device. The phase structure, morphology and composition of TiO 2 were characterized by XRD, TEM and EDX analysis. [ABSTRACT FROM AUTHOR]

Gd2O3@SiO2 nanoparticles with a core-shell structure are synthesized by pulsed laser ablation in liquid (PLAL) in single steps. A Gd2O3 target immersed in tetraethyl orthosilicate (TEOS) is ablated by a microsecond Nd:YAG laser, which induces the generation of a Gd2O3 plasma plume and pyrolysis of the TEOS. We propose that the moment Gd2O3 nanoparticles are formed they will be coated immediately by SiO2 and directly synthesized Gd2O3@SiO2 core-shell nanoparticles. These particles obtain high r1 relaxivity of 5.26 s-1 mM-1 and are used as T1-weighted magnetic resonance imaging contrast agents. It is shown that the PLAL technique is promising for fabricating core-shell structure nanomaterial with potential medical applications. [ABSTRACT FROM AUTHOR]

The water-adsorptive capabilities of Gd2O3@MCM-41 as contrast agents with various gadolinium additions were evaluated by molecular dynamic simulation, which indicates that increasing gadolinum leads to the decrease in water molecules adsorbed on the surfaces of mesoporous silica and Gd2O3 nanocluster. Gd2O3@MCM-41 nanoparticles were synthesized by a one-step method. The measured microstructure and water-adsorptive capability of Gd2O3@MCM-41 consist with their simulated counterparts. The observation disclosed that the nanoparticles injected within mice were distributed in their liver and tumor. The enhancement of in vivo magnetic resonance imaging was detected in the tumor and inferior vena cava of the mice contrasted with Gd2O3@MCM-41. [ABSTRACT FROM AUTHOR]

Abstract: A simple method was developed to directly deposit silver nanoparticles on the surface of silica spheres. The photochemical reduction was carried out by ultraviolet irradiation in air atmosphere at room temperature. The [Ag(NH3)2]+was reduced to silver atoms upon ultraviolet irradiation. Silver atoms subsequently deposited on the surface of silica spheres and agglomerated into silver nanoparticles. Silica spheres with silver nanoparticles of different size and density can be simply controlled by adjusting the UV-light irradiation time. The silver nanoparticles deposited on silica spheres were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron microscopy, and field emission scanning electron microscopy. [Copyright &y& Elsevier]