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941.
A novel design is described for an amperometric biosensor based on NAD(P)-dependent glucose dehydrogenase (GDH) combined with a plasma-polymerized thin film (PPF). The GDH is sandwiched between several nanometer thick acetonitrile PPFs on a sputtered gold electrode (PPF/GDH/PPF/Au). The lower PPF layer plays the role as an interface between enzyme and electrode because it is extremely thin, adheres well to the substrate (electrode), has a flat surface and a highly-crosslinked network structure, and is hydrophilic in nature. The upper PPF layer (overcoating) was directly deposited on immobilized GDH. The optimized amperometric biosensor characteristics covered 2.5-26 mM glucose concentration at +0.6 V of applied potential; the least-squares slope was 320 nA mM(-1) cm(-2) and the correlation coefficient was 0.990. Unlike conventional wet-chemical processes that are incompatible with mass production techniques, this dry-chemistry procedure has great potential for enabling high-throughput production of bioelectronic devices. 相似文献
942.
943.
Ken Hatano Tetsuya Yamazaki Koji Yoshino Naoto Ohyama Tetsuo Koyama Koji Matsuoka Daiyo Terunuma 《Tetrahedron letters》2008,49(39):5593-5596
A novel O-protected lactose (Galβ1→4Glcβ1-) derivative bearing trimethoxysilyl group at the aglycon was developed as a silane coupling agent. Reaction of the coupling agent with tris(2,2′-bipyridine)ruthenium (II) dichloride (Rubpy) doped silica particle gave a Rubpy-doped silica particle peripherally functionalized with O-protected lactose derivative. De-O-protection of the particle with aqueous ammonia provided lactose-coating Rubpy-doped silica particles, combining luminophor encapsulated in silica matrix and carbohydrate having lectin-recognition ability. Specific adhesion of fluorescein isothiocyanate-labeled peanut agglutinin (FITC-PNA) to the lactose-coating Rubpy-doped silica particles was confirmed by fluorescence microscopic analysis. 相似文献
944.
Shin-ya Koyama 《Journal of Number Theory》2008,128(6):1769-1774
We construct the multiple Eisenstein series and we show a relation to the multiple cotangent function. We calculate a limit value of the multiple Eisenstein series. 相似文献
945.
946.
Prof. Dr. Munenori Numata Daiki Kinoshita Naoya Hirose Dr. Tomohiro Kozawa Prof. Hitoshi Tamiaki Yoshihiro Kikkawa Dr. Masatoshi Kanesato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(5):1592-1598
Developing new strategies for controlling polymer conformations through precise molecular recognition can potentially generate a machine‐like motion that is dependent on molecular information—an important process for the preparation of new intelligent nanomaterials (e.g., polymer‐based nanomachines) in the field bordering between polymer chemistry and conventional supramolecular sciences. Herein, we propose a strategy to endow a helical polymer chain with dynamic spring‐like (contraction/expansion) motion through the one‐dimensional self‐assembly (aggregation/disaggregation) of peripheral amphiphilic molecules. In this developing system, we employed a semi‐artificial helical polysaccharide presenting peripheral amphiphilic chlorophyll units as a power device that undergoes contractive motion in aqueous media, driven by strong π–π interactions of its chlorophyll units or by cooperative molecular recognition of bipyridyl‐type ligands through pairs of chlorophyll units, thereby converting molecular information into the regulated motion of a spring. In addition, this system also undergoes expansive motion through coordination of pyridine. We anticipate that this strategy will be applicable (when combined with the established wrapping chemistry of the helical polysaccharide) to the development of, for example, drug carriers (e.g., nano‐syringes), actuators (stimuli‐responsive films), and directional transporters (nano‐railways), thereby extending the frontiers of supramolecular science. 相似文献
947.
Hisanori Sugiura Yoshiaki Saklrai Yoshihide Masuda Hitoshi Takeda Shigekazu Kusabayashi Shunsuke Takenaka 《Liquid crystals》2013,40(3):441-450
Abstract The thermal properties of 4-octyloxyphenyl 4-(4-R-3-nitrobenzoyloxy) benzo-ates (1) and 4-(4-octyloxybenzoyloxy)phenyl 4-R-3-nitrobenzoates (2) have been examined, where R = hydrogen, halogens, alkyl and alkoxy groups. The derivatives of compound 1 incorporating hydrogen, halogens, methoxy and nitro groups show a smectic A phase having a bilayer arrangement, and the others with a long alkoxy group show the SA phase with the monolayer arrangement. The derivatives of compound 2 incorporating halogens, and the nitro group show the SA phase with the monolayer arrangement. The alkoxy derivatives show a smectic C phase as well as the nematic phase. The nitro group at the lateral position tends to increase the ratio of the SA-N transition temperature to the N-I. The effect of the nitro group on the smectic properties has been discussed in terms of the structural and electrostatic nature of the nitro group. 相似文献
948.
The treatment of enantiopure aryl dichloromethyl sulfoxides in THF with strong bases such as LDA, LiHMDS, NaHMDS, and KHMDS resulted in racemization of the sulfur stereogenic center of the sulfoxides even at ?78 °C. The rate of the racemization was found to be dependent on the alkali metal of the bases used. This is the first example of the racemization of the sulfur stereogenic center of α-sulfinyl carbanions at low temperatures. 相似文献
949.
950.