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311.
312.
Iwao Suzuki Akiyo Yamauchi Yoshiko Sakashita Kazuaki Hirose Takashi Miura Takashi Hayashita 《Analytical sciences》2007,23(10):1167-1171
Supramolecular complex formation of phenylboronic-acid-modified beta-cyclodextrin (1) with 1-methyl-4-(4-dimethylaminostyryl)pyridinium (C1SP) in aqueous solutions containing saccharides was fully clarified to gain an insight into the observed D-glucose (D-glc) selectivity of a supramolecular fluorescent probe composed of 1 and the 1-heptyl analogue of C1SP (Chem. Commun., 2006, 4319). At pH 9.6, where 1 was in its anionic form, both the stability and the fluorescence of the 1/C1SP complex were reduced by the formation of boronate esters of 1 with saccharides. Among the saccharides, D-glc had the smallest effect on destabilization of the 1/C1SP complex, almost completely retaining the fluorescence of the 1/C1SP complex that was reduced by other saccharides by approximately 2/3. Under neutral conditions, D-glc enhanced the fluorescence of the 1/C1SP complex by increasing the fraction of anionic 1 while minimally decreasing the stability and fluorescence of the 1/C1SP complex. Although other saccharides also increased the fraction of the anionic 1, their relatively large effects on the destabilization and reduction of fluorescence of the 1/C1SP complex limited the enhancement of the fluorescence of the 1-C1SP system under neutral conditions. 相似文献
313.
314.
Langmuir-blodgett assembly of densely aligned single-walled carbon nanotubes from bulk materials 总被引:2,自引:0,他引:2
Li X Zhang L Wang X Shimoyama I Sun X Seo WS Dai H 《Journal of the American Chemical Society》2007,129(16):4890-4891
315.
316.
Junta Yamamichi Tetsunori Ojima Mie Iida Kimiko Yurugi Takeshi Imamura Eishi Ashihara Shinya Kimura Taira Maekawa 《Analytical and bioanalytical chemistry》2014,406(18):4527-4533
In clinical settings, serum antibody levels serve as markers of pathology. For example, antibodies related to autoimmune diseases are among the conventional targets in laboratory tests. Simple clinical tests can improve the efficacy of laboratory practice. This study describes a single-step, wash-free technique for optically detecting antibodies in human serum through the localized surface plasmon resonance (LSPR) of gold nanoparticles. As a proof-of-concept experiment, the amount of antibiotin dissolved in human serum was measured with a LSPR-based biosensor in a wash-free manner using a conventional 96-well microtiter plate and a plate reader. For an efficient surface modification of biosensors, zwitterionic copolymer was used as a scaffold on the gold nanoparticle surface to immobilize antigen and blocking reagent. Single-step, wash-free measurement of antibiotin in human serum was successfully achieved. In addition, nonspecific responses from serum contents were significantly reduced because both the copolymer and hydrophilic antigen reagent that we employed were composed of poly(ethylene oxide) spacer. Comparative experiments of the antigen-antibody reaction in serum to that in buffered solution revealed that serum is a favorable environment for the biological reaction. In conclusion, our gold-nanoparticle-based LSPR method may provide a rapid and simple way to measure the amount of antibody in serum quantitatively in clinical practice. Figure
Experimental setups illustrating two different methods of surface modification for the gold nanoparticles: biotinylated BSA and zwitterionic copolymer. The amount of antibiotin that attached to biotin on the surface was measured by the peak shift of LSPR spectra using a 96-well microtiter plate with immobilized gold nanoparticles 相似文献
317.
Iwao Sato 《Discrete Mathematics》2007,307(2):237-245
We treat zeta functions and complexities of semiregular bipartite graphs. Furthermore, we give formulas for zeta function and the complexity of a line graph of a semiregular bipartite graph. As a corollary, we present the complexity of a line graph of a complete bipartite graph. 相似文献
318.
Iwao Yamazaki Toshiro Murao Keitaro Yoshihara Masahisa Fujita Kazuyoshi Sushida Hiroaki Baba 《Chemical physics letters》1982,92(4):421-424
Fluorescence lifetimes of pyridine vapor were measured by exciting at various vibrational bands in the lowest-energy region of the S1(n,π*) ← S0 transition. The lifetime varies between 35 and 60 ps, depending on the vibronic level excited. The non-radiative decay from S1 is characterized by particularly fast S1 → S0 internal conversion. 相似文献
319.
Kunihiko Yokoi Toru Ozeki Iwao Watanabe Shigero Ikeda 《Journal of Electroanalytical Chemistry》1982,133(1):73-78
Reduction mechanisms of polarographic reduction waves of Mo(VI) in 0.1–5 M sulfuric acid solutions are described. Three reduction waves are observed when the concentration of sulfuric acid is >3 M. From the results of coulometry and the catalytic behavior of Mo(V), it is concluded that three different reduction mechanisms of Mo(VI) to Mo(V) are present and that two separate reductions of Mo(VI) to Mo(V) and of Mo(V) to Mo(III) are involved at the potential of the third wave. The presence of three reduction mechanisms of Mo(VI) to Mo(V) in sulfuric acid α 3 M seems to indicate the existence of three different chemical species of Mo(VI). Two of these three species are different from the present in 0.1 M sulfuric acid. 相似文献
320.
The rotational isomerism of 1,2-dichloroethane (DCE, CH2ClCH2Cl) adsorbed on Pt(111) was studied in the temperature range of 35-100 K using high-resolution electron energy loss spectroscopy and metastable atom electron spectroscopy. In the coverage below monolayer the physisorbed and chemisorbed species coexist at 35 K in the gauche and slightly distorted trans form, respectively. Owing to the direct Pt-Cl interactions, the nonbonding Cl 3p states of the chemisorbed DCE are split off, giving rise to degradation in symmetry from the pure trans form (C2h). The physisorbed gauche conformers are arranged with the C2 axis parallel (or heavily tilted) to the substrate and converted irreversibly to the pseudo-trans form by heating at 70 K. In the multilayer, the trans and gauche conformers exist at 35 K, where the former population is increased with increasing layer thickness. Upon annealing the bilayer at 80 K, the irreversible conversion takes place to yield a higher population of the gauche conformer in the topmost layer. The conformational stabilities and mutual changes of DCE adsorbed on a metal surface are discussed in terms of intramolecular rotational potential. 相似文献