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1.
A flow-injection system for the determination of 3-hydroxybutyrate in serum is described. 3-Hydroxybutyrate dehydrogenase is immobilized on poly(vinyl alcohol) beads and incorporated in a flow-injection system. 1-Methoxy-5-methylphenazinium methylsulphate reacts with enzymatically generated NADH to give H2O2, which is detected chemiluminometrically with the reaction of luminol and hexacynoferrate(III). Serum is diluted and filtered through an ultrafiltration membrane. The system responds linearly to injected samples (80 μl) in the concentration range 0.5–300 μM; the detection limit is 0.1 μM. The within-day relative standard deviation (n = 90) for 58 μM 3-hydroxybutyrate in serum is 0.8%. The maximum throughout is 20 samples per hour. The immobilized enzyme is stable for at least 1 month. 相似文献
2.
Huricha Baigude Kaname Katsuraya Kohsaku Okuyama Kenichi Hatanaka Emi Ikeda Naokazu Shibata Toshiyuki Uryu 《Journal of polymer science. Part A, Polymer chemistry》2004,42(6):1400-1414
A novel sugar‐containing poly(ornithine) dendrimer is synthesized for possible antigen delivery and related applications. The dendrimer contains an ornithine dendron as interior scaffolding and oligosaccharides on the periphery, which provide an attachment site for a peptide antigen. Maltose or lactose is bound to both hemispherical and spherical poly(ornithine) dendrimer generation 3 (G3) by reductive amination between its reducing end and the peripheral amino group of the dendrimer using a borane‐pyridine complex in a buffer solution at 50 °C. The degree of substitution of sugar is changed by varying the molar ratio of sugar to dendrimer. When the surface of spherical poly(ornithine) dendrimer G3 is modified by binding β‐alanine to the 16 amino groups, highly substituted maltose‐ or lactose‐β‐alanine‐poly(ornithine) dendrimer G3 is obtained in high yield after 7 days of reaction. The structures of these sugar‐containing dendrimers are characterized by NMR and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry analyses. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1400–1414, 2004 相似文献
3.
K. M. A. Salam Hidekazu Konishi Masahiro Mizuno Hisashi Fukuda Shigeru Nomura 《Applied Surface Science》2002,190(1-4):88-95
Polycrystalline (1−x)Ta2O5−xTiO2 thin films were formed on Si by metalorganic decomposition (MOD) and annealed at various temperatures. As-deposited films were in the amorphous state and were completely transformed to crystalline after annealing above 600 °C. During crystallization, a thin interfacial SiO2 layer was formed at the (1−x)Ta2O5−xTiO2/Si interface. Thin films with 0.92Ta2O5–0.08TiO2 composition exhibited superior insulating properties. The measured dielectric constant and dissipation factor at 1 MHz were 9 and 0.015, respectively, for films annealed at 900 °C. The interface trap density was 2.5×1011 cm−2 eV−1, and flatband voltage was −0.38 V. A charge storage density of 22.8 fC/μm2 was obtained at an applied electric field of 3 MV/cm. The leakage current density was lower than 4×10−9 A/cm2 up to an applied electric field of 6 MV/cm. 相似文献
4.
5.
[reaction: see text] A newly developed strategy for construction of eight-membered carbocycles via [6 + 2] annulation that involves the combination of beta-alkenoyl acylsilanes and a vinyllithium derivative is described. A unique feature of this annulative approach is that it enables in one operation and a stereoselective manner construction of eight-membered ring systems containing useful functionalities for further synthetic elaboration from readily available six- and two-carbon components. 相似文献
6.
Post-biotinylation of the alkyl azide derivative of trifluoromethyl phenyldiazirine (TPD) was elucidated to apply a photoaffinity biotinylation technique. A photo-modified polyvinilidene difluoride (PVDF) membrane was used as a photolabeled component and we introduced biotin by Staudinger-Bertozzi ligation. The 15 pmol amount of biotinylated reagent was still effective for the visualization of cross-linked product on the matrix. The results show the potential utility of alkyl azide carrying TPD derivatives in the application of photoaffinity biotinylation, which could be useful for the ligands with tight structural requirements. 相似文献
7.
Koichiro Nakanishi Susumu Okazaki Kenji Ikari Hidekazu Touhara 《Chemical physics letters》1981,84(3):428-432
Monte Carlo calculations have been carried out for pure water and an infinitely dilute aqueous solution of methanol at 298.15 K at ordinary density by the Metropolis method in NTV ensemble. The hydration structure around methanol revealed by a graphic display technique indicates a structure-forming effect near the hydrophobic group. 相似文献
8.
Bai JZ Bardon O Blum I Breakstone A Burnett T Chen GP Chen HF Chen J Chen SJ Chen SM Chen Y Chen YB Chen YQ Cheng BS Cowan RF Cui HC Cui XZ Ding HL Du ZZ Dunwoodie W Fan XL Fang J Fero M Gao CS Gao ML Gao SQ Gao WX Gratton P Gu JH Gu SD Gu WX Gu YF Guo YN Han SW Han Y Harris FA Hatanaka M He J He KR He M Hitlin DG Hu GY Hu HB Hu T Hu XQ Huang DQ Huang YZ Izen JM Jia QP Jiang CH Jin Y Jones L Kang SH Kelsey MH Kim BK Lai YF Lan HB Lang PF Lankford A Li F Li J Li PQ Li Q Li RB 《Physical review D: Particles and fields》1995,52(7):3781-3784
9.
Tanaka H Yamada T Sugiyama S Shiratori H Hino R 《Journal of colloid and interface science》2005,286(2):812-815
Using a hydroxyl group appended free base porphyrin derivative (HP), porphyrin-introduced silica gels were synthesized by a sol-gel process. The HP content in the materials linearly increased with increasing the HP concentration. Meanwhile, free base tetraphenylporphyrin (TPP) with no hydroxyl groups were almost not incorporated into the silica gels. These facts suggested that the interaction between hydroxyl groups of the HP molecules and silica network is considerably strong. The UV-vis characters of HP-introduced materials were almost the same as pure HP molecules. The Beer's plot indicated that the HP molecules in the materials are dispersed. 相似文献
10.
Influence of isosorbide dinitrate concentration on its skin permeability from adhesive matrix devices. 总被引:2,自引:0,他引:2
T Hatanaka M Oguchi K Sugibayashi Y Morimoto 《Chemical & pharmaceutical bulletin》1991,39(7):1802-1805
Adhesive matrix devices containing a model drug, isosorbide dinitrate (ISDN), were prepared with three different types of pressure sensitive adhesives (PSAs). ISDN permeation through excised hairless rat skin from the different devices was measured in vitro. For each PSA type, the steady state permeation rate of ISDN increased proportionally with an increase of ISDN concentration in the PSA and reached a maximum level at a certain concentration. Although the concentrations reaching the maximum skin permeation level varied among PSA types, the maximum rate for each PSA type was largely similar to that for ISDN aqueous suspension. The release rate of ISDN from devices was too fast to influence the skin permeation rate for all devices. In the PSA of devices showing maximum skin permeability, ISDN crystalline was observed by polarizing microscopy and differential scanning calorimetry. These results suggest that the skin permeation of ISDN from adhesive matrix devices was controlled by the thermodynamic activity of the drug in the PSAs. 相似文献