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91.
《Analytical letters》2012,45(7):1226-1240
In this paper, we described a novel sensor based on tiron-doped polypyrrole and carbon nanotubes (CNTs) fabricated on low resistance monolayer-modified glassy carbon electrode. First, the dodecylamine monolayer was chemically modified. Second, CNTs were controllably adsorbed onto dodecylamine. Then, tiron doped polypyrrole was electro-deposited on the CNTs film. The layer-by-layer modified electrode was sensitive to dopamine, while it made no response to even high concentration of ascorbic acid. Parameters influencing the dopamine response were optimized. High performance of the sensor was obtained, such as wide concentration range, low detection limit (3 nM), low background current, high stability, and reproducibility. 相似文献
92.
Single-component monolayer of novel multi-thiol coronary molecule and two-component mixed monolayer composed of coronary molecule and n-alkanethiol on gold substrates are described. The assembly of monolayers is characterized by ellipsometry, infrared spectroscopy and X-ray photoelectron spectroscope. The electrochemical properties of the single- and two-component monolayers are evaluated by cyclic voltammetry and electrochemical impedance spectroscopy experiments. Coronary molecule with multi-thiol groups has the ability to form stable monolayer via the interaction of mercapto groups and Au surface. Electrochemical impedance measurements indicate that 89.9% of the gold surface is blocked by the coronary molecule, which is attributed to the special spatial structure of the coronary molecule. The uncovered site on gold surface in coronary molecule monolayer could be occupied by the second suitable molecule. The mixed monolayer prepared by stepwise assembly of coronary molecule and n-alkanethiol has complete compact packing and few defects. 相似文献
93.
In this review article, we discuss a class of biosensors that exploit the change in the colorimetric properties of noble metal nanoparticles in response to biomolecular binding at their surface. Several sensor fabrication techniques as well as sensor configurations are discussed with an emphasis on their strengths and limitations. We conclude by presenting the future prospects and challenges for the successful transition of this technology from the laboratory to a commercial product. 相似文献
94.
95.
In this review paper we survey the ways in which various micropipet techniques have been used to study the mechanochemical and interactive features of lipid bilayer vesicles and monolayer-coated gas bubbles. Special emphasis will be made on characterizing the barrier properties of grafted PEG layers and how a hierarchical approach that uses a short barrier and extended ligand allows us to start to mimic nature's own solution to the problem of ubiquitous repulsion and specific attraction. The information gained from such studies not only characterizes the membrane and other lipid surfaces and their intersurface interactions from a fundamental materials science perspective, but also provides essential materials property data that are required for the successful design and deployment of lipid-based carriers and other capsules in applications involving this so-called ‘stealthy’ surface. 相似文献
96.
Ming Wen Kejia E Haiquan Qi Lujiang Li Juan Chen Ying Chen Qingsheng Wu Tao Zhang 《Journal of nanoparticle research》2007,9(5):909-917
Dispersed-well FePt nanoparticles with particle size ~5 nm have been prepared by hydrazine hydrate reduction of H2PtCl6·6H2O and FeCl2·4H2O in ethanol–water system. By employing as-synthesized FePt nanoparticles, the monolayer can be formed by LB Technique. The
structural, magnetic properties and electrochemical properties of FePt monolayer were respectively studied by XRD, TEM, VSM
and CHI 820 electrochemical workstation. The as-synthesized particle has a chemically disordered fcc structure and can be
transformed into chemically ordered fct structure after annealing treatment above 400°C. The coercivity of ordered fct FePt
phase can be up to 2515Oe. CVs of 0.5 M H2SO4/0.5M CH3OH on GCE modified with FePt nanoparticles monolayer films illustrate that the as-synthesized FePt is a kind of active electrochemical
catalyst. 相似文献
97.
Junseok Lee 《Surface science》2007,601(16):L91
Sequential stages of formation of a self-assembled monolayer of flat-lying 2,6-dimethylpyridine molecules on a single crystal Cu(1 1 0) surface have been observed by low-temperature scanning tunneling microscopy (LT-STM). At an adsorption temperature of 10 K, all of the molecules are randomly distributed at low coverage upon adsorption. The isolated molecules align their molecular axes parallel to the 〈0 0 1〉 azimuth of the Cu lattice. The nitrogen atom in the molecule is located at the four-fold hollow site. Upon annealing to 100 K, the molecules associate to form head-to-head dimers. The dimer units involve a pair of weak hydrogen bonds between methyl group-hydrogen atoms and N moieties on adjacent molecules, forming a core structure for further growth. In a later stage of self-assembly, single head-to-tail weak hydrogen bonds between ring C-H bonds and N moieties form in chains on the periphery of the central cores, leading to larger domains with a c(6 × 2) overlayer structure. 相似文献
98.
On the framework of coherence theory we discuss the averaged temporal intensity output provided by real-time optical Fourier transformers when the spectral line shape of the stationary source is considered. Some numerical examples are given and the deviations from perfectly monochromatic sources are pointed out. 相似文献
99.
HAN Tian-jiao WANG Qing SONG Feng-rui LIU Zhong-ying LIU Zhi-qiang LIU Shu-ying . Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Center of Mass Spectrometry Changchun P. R. China 《高等学校化学研究》2011,(3):380-384
In vitro models of human colon carcinoma cell line(Caco-2 cell monolayer) and human intestinal bacteria were used to investigate the intestinal transport and biotransformation of resibufogenin and cinobufagin in Chan Su by HPLC/APCI-MSn. The experimental results of Caco-2 cell monolayer demonstrate that the apparent permeability coefficients(Papp) of resibufogenin and cinobufagin are higher than 10-6 cm/s, which indicates that both resibufogenin and cinobufagin have a good absorption in the small intestine.... 相似文献
100.
Tércio de Freitas Paulo Solange de Oliveira Pinheiro Maria Aparecida S. Da Silva Luiz Gonzaga de França Lopes Lucidalva S. Pinheiro Gil F. A. Aquino Márcia Laudelina Arruda Temperini Pedro de Lima Neto Izaura Cirino Nogueira Diógenes 《Electroanalysis》2009,21(9):1081-1089
STM and impedance results of the self‐assembled monolayer (SAM) formed with thionicotinamide (TNA) on gold indicate the presence of defects that increase with the immersion time of the electrode in the TNA solution affecting the SAM electroactivity toward the electron transfer reaction of the cytochrome c metalloprotein and [Fe(CN)6]4? and [Ru(NH3)6]3+ complexes. It was observed that this electroactivity was also affected by the pH of the electrolyte solution. SERS and STM data indicate sulfur coordination to the surface with contribution of the NH2 group. From the dependence of the TNA surface coverage on the temperature and concentration in solution, thermodynamic parameters of adsorption were determined. 相似文献