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91.
The formation of covalently linked composites of multi–walled carbon nanotubes (MWCNT) and glucose oxidase (GOD) with high-function
density for use as a biosensing interface is described. The reaction intermediates and the final product were characterized
by using FT–IR spectroscopy, and the MWCNT-coated GOD nanocomposites were examined by atomic force microscopy (AFM) and transmission
electron microscopy (TEM). Interestingly, it was found that the GOD–MWCNT composites are highly water soluble. Electrochemical
characterization of the GOD–MWCNT composites that were modified on a glassy carbon electrode shows that the covalently linked
GOD retains its bioactivity and can specifically catalyze the oxidation of glucose. The oxidation current shows a linear dependence
on the glucose concentration in the solution in the range of 0.5–40 mM with a detection limit of 30 μM and a detection sensitivity
of 11.3 μA/mMcm2. The present method may provide a way to synthesize MWCNT related composites with other biomolecules and for the construction
of enzymatic reaction-based biofuel cells and biosensors.
Supported by grants from the National Natural Science Foundation of China (NSFC, No. 20125515; 90206037; 20375016) and the
Natural Science Foundation of Jiangsu Province (Grant No. BK 2004210) 相似文献
92.
用碳糊电极阳极溶出法测定桑色素的含量。在0.15mol·L-1NH4Cl 氨水缓冲溶液的介质中富集120s,桑色素在+0.10V(vs.SCE)左右出现阳极溶出峰。其峰电流的大小与桑色素的浓度呈线性关系。线性范围为4.00×10-6~1.40×10-5mol·L-1,相关系数为0.9996,检出限可达1.00×10-6mol·L-1,回收率为99.87%~102.01%。此法不用汞电极,灵敏度高,操作方便、快捷,成功地用于甘草提取物中桑色素的测定。 相似文献
93.
Preparation and characterization of nitrogen-doped TiO2 photocatalyst in different acid environments
Ye Cong Ling Xiao Jinlong Zhang Feng Chen Masakazu Anpo 《Research on Chemical Intermediates》2006,32(8):717-724
Nitrogen-doped TiO2 powders were successfully prepared by a wet method, i.e., a micro-emulsion-hydrothermal method, in different acid environments.
Several characterization techniques, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-visible diffuse
reflectance spectra, were combined to determine the crystal phase, concentration and chemical states of the nitrogen doped
in TiO2. The high photocatalytic activity of the nitrogen-doped TiO2 was evaluated through the decomposition of rhodanmine B under visible light irradiation. It was suggested that the doped
nitrogen formed oxynitride (NO) and produced impurity states at higher above the valence band of TiO2. Therefore, the nitrogen doping could enhance the response of photocatalyst to the visible light and improve the photocatalytic
activity because of the narrowing of band gap of TiO2. 相似文献
94.
95.
《Electroanalysis》2004,16(12):994-1001
The interfacial behavior of electrodes fabricated from carbon film resistors of 2 and 20 Ω in supporting electrolyte solutions of varying pH used in electroanalytical experiments has been characterized by electrochemical impedance spectroscopy with complementary cyclic voltammetric experiments. Equivalent circuits are proposed to fit the experimental data and the influence of electrode pretreatment has also been investigated. 相似文献
96.
TiO2光催化反应及其在环境保护中的应用 总被引:8,自引:0,他引:8
本文简要介绍了TiO2光催化剂的作用机理,讨论了影响TiO2光催化效率的因素及解决途径,综述了光催化在环境保护中的最新应用。 相似文献
97.
98.
99.
We have obtained novel photosensitive materials containing a semiconductor photocatalyst and a dye sensitizer. We have studied the activity of the latter in the reaction of photoreduction of methylene blue, and we consider possible mechanisms for the photocatalytic effect. 相似文献
100.
Adel Attia Markéta Zukalová Jiří Rathouský Arnošt Zukal Ladislav Kavan 《Journal of Solid State Electrochemistry》2005,9(3):138-145
A mesoporous electrode material whose structure is composed of anatase nanocrystals stabilized by alumina is reported. Powder X-ray diffraction shows the anatase phase only, but micro-Raman spectroscopy shows that the materials have a core-shell morphology with grains of bulk anatase covered by a thin rutile layer on the surface. This structure is unique when compared to analogous materials stabilized by zirconia (PNNL-1). Nitrogen adsorption isotherms demonstrate a monotonous increase in surface area and mesopore volume with increasing Al content. Thin film electrodes from these materials were characterized by lithium insertion electrochemistry. Cyclic voltammograms exhibit significant differences in Li accommodation in Al-free and Al-stabilized materials. 相似文献