巻号一覧
62 巻, 5 号
選択された号の論文の19件中1～19を表示しています
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宮浦 憲夫, 萬代 忠勝2004 年 62 巻 5 号 p. 410
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーPDF形式でダウンロード (343K) -
岩本 正和2004 年 62 巻 5 号 p. 411-415
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーNovel catalyses on mesoporous materials, especially on MCM-41 (M 41), have been summarized on the basis of our recent results. The uniform surface of M 41 could result in the high selectivity in organic syntheses. For example, trans-stilbene oxide was obtained with 93% yield from stilbene and TBHP on Mn-M 41. The oxidation of sulfide with H2O2 proceeded asymmetrically on Ti-M 41 in the presence of optically active tartaric acid.
The pure silica M 41 itself was further found to show unique acidity and catalyze various reactions including acetalization, Friedel-Crafts, Mukaiyama-Aldol, and Diels-Alder reactions. In addition, the combination of the M 41's acidity with nickel ion led the new catalytic reaction in which ethene can directly be converted to propene. This reaction consists of the dimerization of ethene to form 1-butene, the isomerization of 1-butene to 2-, and finally the metathesis of 2-butene and ethene to give propene.抄録全体を表示PDF形式でダウンロード (1480K) -
吉沢 道人, 藤田 誠2004 年 62 巻 5 号 p. 416-423
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーMolecular self-assembly via metal-coordination has been providing a very useful method for the non-covalent synthesis of nanometer-sized molecular architectures. We have been showing that the simple combination of cis-endocapped square-planar Pd (II) complexes with pyridine-based bridging ligands gives rise to the quantitative self-assembly of nano-sized hollow structures such as cages, bowls, tubes, and capsules. These hollow compounds provide unique distinct cavities with their own size and shape and allow the encapsulation of neutral organic molecules at fixed position of the cavities. With an expectation that the subsequent chemical reactions of the guests are highly controlled by the cavities, we have examined the chemical reactions of the encapsulated guests within the hollow compounds. Accordingly, we discuss here cavity-directed synthesis within the self-assembled molecular nano-space where the chemical properties and reactivities of encapsulated molecules are suitably controlled by the confined space.抄録全体を表示PDF形式でダウンロード (1931K) -
植村 卓史, 北川 進2004 年 62 巻 5 号 p. 424-432
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーChemistry of the coordination polymers in these recent decades has been extensively advanced, affording various architectures, which are rationally constructed from a variety of molecular building blocks and interactions between them. This manuscript contains nanospace and function engineering. These functions realized not only industrial application such as separation, storage and heterogeneous catalysis but also unique nano-sized vessels for low-dimensional ordered arrays. In this review article, we present a new cutting edge regarding chemistry and physics “of micropore” and “in micropore” for porous coordination polymers.抄録全体を表示PDF形式でダウンロード (2714K) -
山元 公寿, 樋口 昌芳2004 年 62 巻 5 号 p. 433-439
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーDendritic polyphenylazomethines (DPAs) having a regularly branched structure and a single molecular weight were synthesized via dehydration of aromatic amines with aromatic ketones. We found stepwise radial complexation with SnCl2 in DPAs by spectroscopic observation as stepwise shifts of the isosbestic point, and further supported by means of NMR, TEM, and shell-selective reduction of imines. Functionalization of DPAs was achieved by exploiting the modification methods of the core and terminals. Encapsulation/releasing of iron ions in DPA was electrochemically controlled due to the different complexation ability of Fe (II) and Fe (III) ions with the imines. DPAs were also applied to hole transporting materials in EL devices and catalysts for reduction of carbon oxide, and their efficiency was enhanced by the complexation with SnCl2.抄録全体を表示PDF形式でダウンロード (1378K) -
一次元金属錯体を主鎖とするナノワイヤーの開発君塚 信夫2004 年 62 巻 5 号 p. 440-446
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーThe ability to manipulate nano to microscopic superstructures based on molecular self-assembly holds a key to develop future nanomaterials. In this review, the design and synthesis of self-assembling inorganic nanowires are introduced. First, lipophilic nanowires consisting of cationic, one-dimensional mixed valence PtII/PtIV complex and anionic lipids are developed. They display thermal dissociation and re-assembling characteristics and provide the first example of self-assembling conjugated nanowires. It also enables bottom-up manipulation of stereo-nanoarchitectures on solid surfaces. Second, heat-set gel-like networks are self-assembled from lipophilic Co (II) triazole complex in chloroform. It affords blue gel at room temperature, whose color is characteristic of the tetrahedral (Td) coordination structure. Upon cooling, the gel is dissolved into pale pink solution (Oh complex) and this change was thermally reversible. The reversible, heat-set gelation of organic liquids has been unprecedented. These new approaches and findings provide new dimensions in the fields of nano- and materials chemistry.抄録全体を表示PDF形式でダウンロード (2079K) -
菅原 正2004 年 62 巻 5 号 p. 447-458
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーThiol-derivatized gold nanoparticles has drawn much attention as a building block of nano-scaled electronic devises. As a fuctional thiol ligand, π-conjugated radical thiols, e.g p-mercaptophenyl nitronyl nitroxide, etc., have been synthesized. Nanoparitcles with the average particle size of 4 nm were chemisorbed by 100 lignads of p-mercaptophenyl nitronyl nitroxde and they were isolated and characterized. The ESR spectral peak width of the radical thiol on the nanoparticle was extremely broadened (ΔHpp= 30 mT at RT), suggesting the significant magnetic interaction between an unpaired electron of the radical uint and conduction electrons of gold nanoparticles.
Network structures of gold nanopartilces connected by σ- or π-molecular nanowires made of alkanedithiol or oligothiophene with protected thiol groups were also prepared. It is to be noted that the network structures of nanaoparticles connected with molecular wires were prepared through a self-organization process. They are semiconductors with small activation energies (ca. 20 meV at temperatures higher than 40 K, and ca. 6 meV at lower than 40 K), suggesting a hopping mechanism for the electronic transportation in a higher temperatures region (T = 40 K) and a tunneling mechanism in the lower temperature (T < 40 K).抄録全体を表示PDF形式でダウンロード (3730K) -
尾池 秀章, 相田 卓三2004 年 62 巻 5 号 p. 459-463
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーRecent progress in our studies on construction of nanomaterials was described based on supramolecular and macromolecular approaches. With biologically important peptide bundling as a motif, we developed a novel method to sense helical conformations of oligopeptides, where the stereochemical interaction between static and dynamic helices plays an important role. We also demonstrated that chaperonin proteins can entrap and stabilize artificial guests such as semiconductor nanoclusters even in boiling water, but can release those artificial guests in response to ATP. Furthermore, the discovery of physical gelation of room-temperature ionic liquids of imidazolium salts on grinding in the presence of single-walled carbon nanotubues (SWNTs) was described. On the basis of this finding, a novel electroconductive SWNT/polymer composite, which showed a significant enhancement in dynamic hardness, was successfully fabricated.抄録全体を表示PDF形式でダウンロード (1216K) -
原田 明2004 年 62 巻 5 号 p. 464-470
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーRecently, much attention has been focused on construction of supramolecular polymers because of their unique structures and functions. Supramolecular polymers are ubiquitous in nature, especially in biological systems, such as microtubules, flagella, virus, and phages. They have unique structures and functions such as self-replication, self-restoration, transportation, and movements. If such supramolecular systems are available by synthetic methods, we are able to obtain various interesting materials and functional devices. In the first part of this review, construction of nano-structures using cyclodextrins as a cyclic building block is described. Rotaxanes and polyrotaxanes of various kinds are introduced. In the last part, construction of supramolecular structures using biopolymers such as DNA and immunoglobulins are described. In this review, I would like to show some recent advances in this field from the viewpoint of polymer science and synthetic chemistry.抄録全体を表示PDF形式でダウンロード (2155K) -
兪 燕蕾, 中野 誠, 池田 富樹2004 年 62 巻 5 号 p. 471-479
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーSeveral kinds of photodeformable polymer systems containing azobenzenes, capable of generating photomechanical effects, are reviewed. In polymer amorphous systems including monolayers, gels and solid films, trans-cis photoisomerization of the azobenzene moieties accompanied by geometrical and dipolar changes caused contraction and expansion of the systems. Recently, polymer liquid-crystalline elastomers containing azobenzenes, a novel system able to produce the photomechanical effects, have been developed to achieve fast and large photoinduced deformations. It is interesting that not only photoinduced contraction but also photoinduced bending have been achieved. These deformations are ascribed to the subtle variation in microscopic ordering during the photochemical phase transition of the polymer liquid-crystalline elastomers. This new photomechanical system is potential for application in driving micromachines and nanomachines without the aid of batteries, motors and gears.抄録全体を表示PDF形式でダウンロード (2024K) -
小夫家 芳明2004 年 62 巻 5 号 p. 480-489
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーImidazolylporphyrinatoZn gave a complementary coordination dimer of extraordinary stability. It exhibited excellent properties as a mimic of the structure and the function of the special pair of the reaction center in photosynthetic bacteria. Coupling of imidazolylporphyrinatoZn at the meso position afforded an array of a few hundreds nanometer to a micrometer scale. The linear array could be regarded as a unit of energy/electron transfer since no fluorescence quenching was observed by the array formation. When imidazolylporphyrinatoZn's were linked by a meta-phenylene grouping, macrocyclic porphyrin rings composed of 10 and 12 porphyrin units were obtained to represent the the light harvesting complex B 850 of photosynthetic bacteria. The linear array was attached on gold surface by thiolate extended from porphyrin. The assembled porphyrins have demonstrated significant improvement of the efficiency of photocurrent generation.抄録全体を表示PDF形式でダウンロード (1966K) -
吉田 久美, 尾山 公一, 近藤 忠雄2004 年 62 巻 5 号 p. 490-499
発行日: 2004/05/01
公開日: 2010/01/22
ジャーナル フリーRed, purple and blue flower color is mainly due to anthocyanins. The color development and stability of anthocyanin are effected by co-existence of co-pigment and metal ions, and pH. Our chemical studies elucidated that the color is stabilized and varied by formation of a supramolecule. Especially beautiful blue flower colors, found in blue dayflower and blue salvia, are developed by a metalloanthocyanin, a stoichiometric supramolecular metal complex pigment.
The metalloanthocyanins are composed with six molecules of anthocyanins, six molecules of glycosylflavones, and 2 atoms of metal ion and the diameter is ca. 3 nano meter. Under formation of metalloanthocyanin fine chiral molecular recognition occurs. To clarify the mechanism we synthesized chiral glycosylflavones derivatives according to our newly invented method of direct C-and O-glycosylation to the flavonoid nucleus. Reproduction experiment from the components (anthocyanin, flavone and metal ion) including chiral isomer of the flavones bearing L-glucose was carried out. As a result, the 4'-D-glucoside of the flavone is essential for formation of metalloanthocyanin, but the L-sugar is not.
As the petal tissue is not homogenous, both the epidermides are colored. For elucidation of true flower color development in a living petal cell, various analytical methodologies including nano-technology must be applied. For this purpose one cell analysis by pH-microelectrode, a nano-HPLC, a pico mole metalanalysis and microscopic photometry were carried out. The mech-anism of flower color change of morning glory, Ipomoea tricolor, from purple to blue during blooming, and color variation of hydrangea was studied.抄録全体を表示PDF形式でダウンロード (1901K) -
その構造と機能吉田 隆志, 波多野 力, 伊東 秀之2004 年 62 巻 5 号 p. 500-507
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーLarge-size secondary metabolites with dimeric-oligomeric and/or dendrine-type structure from higher plants are regarded as natural nanomolecules which are constructed in a bottom-up pathway from small molecules under biological condition. Among them are polyphenols classified as tannins which have large molecular weights ranging from 500 to 4000, and strong affinity to proteins, alkaloids and heavy metals to form complex molecules (precipitates). They constitute two major groups : one is condensed tannins (proantocyanidins), which are composed of flavan-3-ol units linked through C-C bond, and the other is hydrolyzable tannins, which are principally multiple esters of D-glucose with gallic acid and its oxidative metabolites. This paper reviews the diverse structural characteristics of both tannins, especially ellagitannin oligomers up to pentamers, and examples of their biological activities. Formation of insoluble and soluble complex between tannins and proteins are also described.抄録全体を表示PDF形式でダウンロード (1370K) -
DNA構造制御と金属錯体のナノ集積化田中 健太郎, 塩谷 光彦2004 年 62 巻 5 号 p. 508-513
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーDNA has a structural basis for the “bottom-up” fabrication of functionalized molecular building blocks. In particular, the replacement of hydrogen-bonded DNA base pairing for alternative one would lead to a novel tool for re-engineering DNA. Recently, we have synthesized a series of artificial nucleosides bearing metal ligands instead of natural nucleobases and demonstrated that metal complexation between the nucleosides effectively drives base pairing. This review describes our recent approaches to metal-based strategy directed towards self-assembled metal arrays within DNA as well as towards structural control of DNA. This strategy provides a new method for self-assembled metal arrays in a predesigned fashion, leading possibly to metal-based molecular devices such as molecular magnets and wires.抄録全体を表示PDF形式でダウンロード (1346K) -
北薗 英一, 兼子 博章, 三好 孝則, 宮本 啓一2004 年 62 巻 5 号 p. 514-519
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーElectrospinning (ESP) is a powerful method to produce polymer fibers with nanometer-scale diameters. This article describes the application of nanofiber using polylactic acid for tissue engineering. The diameter and surface structure of nanofiber were easily controlled by the conditions of the ESP.
The influences of fiber diameter on cell adhesion and proliferation were examined by culutivating NIH 3 T 3 (fibroblast cell) on nanofibrous meshes. As a result, it was proved that the control of cell adhesion and proliferation was accomplished with changing a fiber diamter.
We succeeded in the production of a new biodegradable and elastic material which was a combined nanofiber with cross-linked elastin. The obtained tubular material showed excellent mechanical property equal to blood vessel and peripheral nerve tissue. Finally, the regeneration of peripheral nerve axon was observed by transplantation using rat model with sciatic trauma.抄録全体を表示PDF形式でダウンロード (2366K) -
明石 満, 赤木 隆美2004 年 62 巻 5 号 p. 520-528
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーMonodisperse polymeric nanospheres, which consist of hydrophobic core and hydrophilic corona on their surfaces, were prepared by the free radical dispersion copolymerization of hydrophobic monomers and hydrophilic macromonomers in a polar solvent. For example, copolymerization of methacrylate-terminated poly (ethylene glycol) (PEG) macromonomers and styrene in ethanol/water mixture gives water dispersible PEG coated nanospheres with a mean diameter around 100-2000 nm. An electron spectroscopy for chemical analysis (ESCA), dynamic light scattering (DLS) and transmission electron microscopy (TEM) observation of ultrathin cross section embedded in a resin supported accumulation of PEG component at the surface of nanospheres. The core-corona type nanospheres can be widely applied to various technological and biomedical applications, because of their possible variety of chemical structure. These nanospheres were utilized as oral drug carriers for peptide drugs physically adsorbed on the nanosphere surfaces, and demonstrated to be useful carrier for incorporating highly water-soluble peptides. Moreover, lectin-immobilized nanospheres could efficiently capture HIV-1 particles and HIV-1-capturing nanospheres may have great potential as a prophylactic vaccine against HIV-1 infection through sexual intercourse.抄録全体を表示PDF形式でダウンロード (2556K) -
ウイルスサイズ (50nm) を目指して青山 安宏2004 年 62 巻 5 号 p. 529-533
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーEndocytosis is a drinking activity of eukaryotic cells, which thereby ingest a part of their plasma membrane to form endocytic vesicles (≤100 nm), into which external objects such as viruses are swallowed. It is of an utmost importance to control the size of artificial molecular (gene, drug, and probe) delivery machines in this viral size range. A 7040 base-pair plasmid DNA pCMVluc can be stoichiometrically coated with 5 nm sized glycocluster nanoparticles (GNPs) formed by micellar aggregation of calix [4] resorcarene-based glycocluster amphiphile to give compactly packed and monomeric glycoviruses of a size of 40-50 nm. The lactose-functionalized neutral virus thus obtained can efficiently transfect hepatic cells via receptor-mediated endocytosis without any notable cytotoxicity. It works in vivo (mouse), too. We also paid attention to the endocytosis susceptibilities of GNP (5 nm) as well as a 15 nm sized, saccharide-coated quantum dot species, in light of that of glycovirus. The dramatic decrease in the activities with decreasing sizes reveals an optimal size at around 50 nm. The size selectivity thus arises from size complementarity in the encapsulation of nanometric guest particles by endocytic vesicles as a macrobiomolecular host.抄録全体を表示PDF形式でダウンロード (1265K) -
宝田 徹, 前田 瑞夫2004 年 62 巻 5 号 p. 534-539
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーHighly sensitive and selective DNA detection has attracted extensive attention for its importance in clinical gene diagnosis. Recently, we developed a simple method for visually detecting single nucleotide mutation by using spontaneous aggregation of DNA-linked colloidal nanoparticles, which was prepared through the phase transition of the amphiphilic copolymer consisting of DNA as the hydrophilic part and thermo-responsive poly (N-isopropylacrylamide) as the hydrophobic part. Adding the complementary DNA into the nanoparticles dispersion, the nanoparticles aggregated rapidly by a non-crosslinking mechanism, based on the salting-out techniques. The aggregation of DNA-linked colloidal nanoparticles was induced by the duplex formation on their surfaces. The instabilization of the nanoparticles would be derived from the decrease of both electrostatic repulsion and entropic effect of the DNA strand tethered to the surfaces of nanoparticles. In contrast, the nanoparticles kept dispersing in the presence of the point-mutated DNA under the identical conditions. Moreover, we improved this method for detecting single nucleotide mutation of sample DNA longer than the DNA attached to the surfaces of the nanoparticles.抄録全体を表示PDF形式でダウンロード (1240K) -
小林 勝2004 年 62 巻 5 号 p. 540-543
発行日: 2004/05/01
公開日: 2009/11/13
ジャーナル フリーWe introduce about the mission and organization of “Nanotechnology Business Creation Initiative” that was established in 15th Oct in last year. And we also introduce about R&D projects of chemical nanotechnology enforced by METI (Ministry of Economy, Trade and Industry). And then we explain the outline of expectation of chemical industry for “Nanotechnology Business Creation Initiative”.抄録全体を表示PDF形式でダウンロード (705K)
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