Abstract: A polyion complex is provided, comprising a double stranded nucleic acid containing a poly(ethylene oxide)-modified oligo- or poly-nucleotide and a polycationic compound, which is an effective delivery means of a gene to a target cell.

Abstract: A surface on which adsorption of protein (e.g., BSA) is markedly suppressed is provided, by contacting solutions of polymers whose chief component is poly(ethylene oxide) having binding sites to sensor surfaces with biosensor surfaces plural times to link the polymers.

Abstract: This invention provides a finely particulate composite wherein a fine particle of block copolymer having a poly(ethyleneglycol) chain segment and a poly(meth)acrylate ester chain segment containing, on its side chain, a tertiary amino group and/or a secondary amino group has, encapsulated therein, a carbon compound, e.g., fullerene or carbon nanotube which may contains, encapsulated therein, a metal. This composite is water-soluble, and is usable as an active oxygen scavenger. This composite, when it has a metal encapsulated therein, is usable as a contrast medium.

Abstract: This invention provides a method to detect analyte which comprises preparing fine particles which have a chargeable group in their core and a hydrophilic polymer chain in their shell; obtaining an agglutinated matter by forming a biologically specific bond between a specific residue on the surface of fine particles and analyte, and by simultaneously forming a bond by the electrostatic interaction between impure protein and said particles; and subsequently cleaving only the latter bond by raising ionic intensity. Thus, this invention provides a method to detect analyte with rapidity and high sensitivity with use of agglutination reaction.

Abstract: A crosslinked polymer or polymer fine particles which can be obtained through copolymerization of at least a macromonomer having a polyethylene glycol segment, a comonomer having tertiary amine groups in its side chains and a crosslinking agent are provided. Said crosslinked polymer can be provided in the form of polymer nano- or micro-spheres; and also as conjugate nano- or micro-spheres with their core parts fixing or encapsulating metal or semiconductor ultrafine particles.

Abstract: A substrate surface on which either a substance to detect analyte or an analyte per se is immobilized, which surface is formed by a treatment of substrate surface with a liquid which contains uncrosslinked polymer based on polyethylene glycol chain segment, said treatment conducted either simultaneously with the immobilization of said substance or analyte or after said substance or analyte has been immobilized on said surface. The non-specific adsorption of impurity protein or the like which is co-existent in sample for assay is significantly restrained.

Abstract: A stabilized dispersion of metal fine particles comprising, fine particles of metal which is obtained by reducing at least one metallic acid or salt thereof selected from the group consisting of haloauric acid, haloplatinic acid, silver nitrate and halorhodic acid by a reducing agent in the aqueous solution of (1) R-PEG-SX [R is a functional group selected from the group consisting of acetal, aldehyde, hydroxyl group, amino group, carboxyl group, active ester group, azide group, biotin group, monosaccharide, oligosaccharide, amino acid, nucleic acid, allyl group, vinyl benzyl group, methacryloyl group and acryloyl group, PEG is —(CH2CH2O)n—, X is H or pyridylthio group] or (2) R-PEG/PAMA (given structural formula A), and said fine particles load a polymer having PEG unit possessing above mentioned functional group on the surface.

Abstract: A conjugate which comprises fine porous particles (on which functional substance may be adhered) and a polymer based on water-soluble high molecular chain segment, and the use of the conjugate (for the purpose of stably supporting, or slowly releasing, a physiologically active substance, or the like).

Abstract: This invention provides a method to effectively incorporate inorganic fluorescent substance or inorganic contrast medium into latex polymer particles which are used for diagnostic test or the like, and also provides thus produced fluorescent substance-containing latex polymer particles which show decreased non-specific adsorption of protein or the like. Said latex polymer particles are produced by making latex-forming monomer, macromer which has at least a hydrophilic polymer segment and an inorganic fluorescent substance or an inorganic contrast medium co-existent simultaneously in an aqueous medium, and subjecting them to a polymerization reaction.

Abstract: A diaminobenzene compound is disclosed which is represented by the formula (1). By reacting this compound with a tetracarboxylic acid (derivative), there can be obtained a polyimide which has charge carrier transport properties and is excellent in heat resistance, film strength and thin-film properties.

Abstract: This invention provides latex particles wherein non-specific adsorption or binding of undesired impurities which usually accompanies the use of latex particles is inhibited, and a process to produce such latex particles. This invention also provides diagnostic agent which contains said particles. In another embodiment, this invention provides latex particles comprising both a ligand group-holding site which has a ligand group on the one terminal and is bound, on the other terminal, to latex particles, and which has a long chain of polyoxyethylene; and a non-specific adsorption-inhibiting site which is bound, at one terminal, to latex particles, and which has a short chain of polyoxyethylene. In this embodiment, this invention also provides a process to produce said particles.

Abstract: This invention provides PEG-modified semiconductor nanoparticles of which fluorescence intensity is effectively inhibited from lowering, which are capable of forming a stable dispersion in water, and which are capable of bonding easily with biomolecules having specific recognition, as well as methods for conveniently preparing such nanoparticles, and a material for biological diagnosis. The water-soluble PEG-modified semiconductor nanoparticles of the present invention includes a structure having PEG of a number average molecular weight of 300 to 20000 having a thiol group at one end, bonded via cadmium to II–VI semiconductor nanocrystals of a core-shell structure having a ZnX (wherein X stands for O, S, Se, or Te) shell.

Abstract: The present invention is directed to a coated biomedical device said micelle having a hydrophilic outer shell and a hydrophobic inner core, or a hydrophobic outer shell and a hydrophilic inner core said micelle comprised of a block copolymer having a HLB value ranging from about 1 to about 40. The medical device may have one coating thereon or multiple coatings. The present invention is also directed to the use of the micelle as a drug carrier.

Abstract: By using an electrophoretic buffer comprising a polymerized polymer micelle formed by the steps comprising dispersing into an aqueous medium a block copolymer represented by HPLS-HPBS-PLZA, wherein HPLS is a hydrophilic polymer segment, HPBS is a hydrophobic polymer segment, and PLZA is a polymerizable group having an ethylenically unsaturated double bond, and polymerizing the block copolymer as a buffer for a capillary electrophoresis or a microchip electrophoresis, pressurizing the sample after introduction at a given pressure for a given time period, and electrophoresing in an electrophoretic electric field, a polymer compound such as DNA can be separated rapidly and in high separation ability.

Abstract: Disclosed are block copolymers represented by the following general formula (I) wherein AI represents a hydroxyl group or an organic residue derived from an anionic polymerization initiator, R represents a hydrogen atom or an acyl group, NP represents a residue derived from a nucleophilic reagent, m is an integer of 2 to 20,000, and n is an integer of 1 to 20,000.

Abstract: A polymer composition is provided, which contains a polymer or copolymer having a mercapto group at one end and functional group or ligand at the other end and also having a polyethylene glycol segment. Such a composition can form a biosensor surface of reduced non-specific adsorbability for proteins and the like.

Abstract: A crosslinked polymer or polymer fine particles which can be obtained through copolymerization of at least a macromonomer having a polyethylene glycol segment, a comonomer having tertiary amine groups in its side chains and a crosslinking agent are provided. Said crosslinked polymer can be provided in the form of polymer nano- or micro- spheres; and also as conjugate nano- or micro-spheres with their core parts fixing or encapsulating metal or semiconductor ultrafine particles.

Abstract: A surface on which adsorption of protein (e.g., BSA) is markedly suppressed is provided, by contacting solutions of polymers whose chief component is poly(ethylene oxide) having binding sites to sensor surfaces with biosensor surfaces plural times to link the polymers.

Abstract: The invention provides high sensitivity bioassay sensor systems in which non-specific adsorption of impurities such as, for example, proteins, in biological samples is inhibited. Polyethylene glycolated particles enclosing metal or semi-conductor which is in common with the sensor material are used for amplification.

Abstract: A core-shell particle including a signal-generating substance therein, wherein the core-shell particle consists of (1) a core portion substantially made of a water-insoluble polymer compound; and (2) a shell portion substantially made of a water-soluble polymer compound having a reactive functional group, and covering a surface of the core portion in the manner of bristles of a brush; and the core portion and the shell portion are, as a whole, a block copolymer of a water-insoluble polymer and a water-soluble polymer, characterized in that the signal-generating substance is included in the core portion, is disclosed, and a process for producing the same is also disclosed. The core-shell particle including a signal-generating substance therein is useful as a labeling substance in which neither radioisotopes having handling restrictions nor unstable enzymes are required, a high sensitivity superior to fluorescent substances is achieved, and nonspecific absorption does not occur.