Abstract: An objective is to provide Si/Si3N4 system nanosized particles each exhibiting reduced environmental load together with minimized bio toxicity, excellent chemical stability, enhanced relative light emission intensity, and less degradation of emission intensity during continuous exposure to light; a biosubstance labeling agent capable of keeping on labeling a biosubstance exhibiting luminance enhanced for a long duration with the Si/Si3N4 system nanosized semiconductor particle of the present invention; and also a method of manufacturing the Si/Si3N4 system nanosized semiconductor particle of the present invention.

Abstract: Disclosed are core/shell type semiconductor nanoparticles exhibiting a sufficient emission intensity without causing a blink phenomenon (blinking). The core/shell-type semiconductor nanoparticles have an average particle size of from 2 to 50 nm and comprise an intermediate layer between a core portion and a shell portion, wherein band gap widths of bulk crystals which have the same compositions as those of the core portion, the intermediate portion and the shell portion, respectively, are in the order of: core portion<shell portion<intermediate layer.

Abstract: Disclosed is a fluorescent semiconductor microparticle assembly comprising at least three kinds of fluorescent semiconductor microparticles with an average particle size of from 1 to 10 nm, having the same chemical composition, a different average particle size and a different emission maximum wavelength in the emission spectra, wherein a standard deviation of emission intensity in each of the at least three kinds of fluorescent semiconductor microparticles is not more than 15%.

Abstract: Disclosed are an immunochromatographic medium and an immunochromatographic method in which, even when plural items exceeding four items are detected which are the number of colors that can be detected by colored latex particles, the plural items can be detected and quantified simultaneously. The immunochromatographic medium comprises a support, a label-attached reagent immobilized on a labeling agent, and detection portions on which a material capable of combining with a substance to be detected in a sample is immobilized, the label-attached reagent and the detection portions being provided on the support, featured in that the labeling agent is a phosphor nanoparticle and the detection portions are shaped in the form of dots.

Abstract: A semiconductor nanoparticle and semiconductor nanorod that have optical characteristics (luminescence intensity and emission lifetime) superior to those of conventional core/shell nanosized semiconductors. There are provided a triple-layer semiconductor nanoparticle, and triple-layer semiconductor nanorod, having an average particle diameter of 2 to 50 nm and comprising a core layer, an interlayer and a shell layer, wherein the layers are composed of different crystals, and wherein the crystal constructing the shell layer exhibits a band gap greater than that of the crystal constructing the core layer, and wherein the crystal constructing the interlayer has a lattice constant assuming a value between those of the crystal constructing the core layer and the crystal constructing the shell layer.

Abstract: An inorganic nanoparticle labeling agent having adaptability for being employed as a labeled material in the field of biology and medical science and capable of emitting fluorescence at a stable emission intensity is disclosed, comprising inorganic nanoparticles which were surface-modified with an organic compound, wherein the inorganic nanoparticles exhibit an average particle size of 1 to 10 nm, the organic compound is a compound containing a polyethylene glycol chain, the average particle size D of the inorganic nanoparticle labeling agent is from 8 to 25 nm; and an amount M (mol) of the organic compound per inorganic nanoparticle and a length L (nm) of the organic compound measured from an inorganic nanoparticle surface meet the relationship represented by the following formula (I): (M×1022)×L/D=1.0?4.

Abstract: A nanoparticle labeling which is simultaneously usable in the combination of X-ray imaging with optical imaging and the combination of X-ray imaging and optical imaging with magnetic resonance imaging characterized by comprising core/shell type semiconductor nanoparticles having an average shell thickness of 0.1 nm or more but not more than 10.0 nm together with an X-ray sensitive material for the former combination, and core/shell type semiconductor nanoparticles having an average shell thickness of 0.1 nm or more but not more than 10.0 nm together with an X-ray sensitive material and magnetic particles for the latter combination.

Abstract: Disclosed is a fluorescent labeling agent containing quantum dots, which exhibits little fluctuation in luminous properties in accordance with the environment where the fluorescent labeling agent is stored and therefore has high environmental stability, and which has high luminous intensity. Specifically disclosed is a fluorescent labeling agent containing quantum dots, which comprises: (1) a fluorescent labeling agent core part which comprises at least three quantum dots per a fluorescent labeling agent and a protective material; and (2) an organic surface-coating layer which coats the fluorescent labeling agent core part, wherein the fluorescent labeling agent core part has an average particle diameter of 10 to 50 nm.

Abstract: A detection method for detecting a substance such as a virus which achieves enhanced detection sensitivity even in trace amounts of a substance to be detected and is also simple and superior in visual determinability is disclosed, comprising contacting a complex of a substance to be detected and a semiconductor nanoparticle-labeled probe capable of bonding the substance with an immobilized capture reagent capable of bonding the substance to detect the substance. A detection kit is also disclosed.

Abstract: There is provided semiconductor nanoparticles which exhibit enhanced emission efficiency, excellent emission intensity, reduced variation range of emission characteristics among lots and among particles and are excellent in stability and reproducibility. There is further provided a fluorescent labeling agent and molecule/cell imaging method by use of the same. Semiconductor nanoparticles having an average particle size of 1 to 20 nm is disclosed, comprising a dopant of a heteroatom which is identical in valence electron configuration with a main component atom forming the semiconductor nanoparticles or an atomic pair of the heteroatom, and the dopant is distributed on or near a surface of the semiconductor nanoparticles.

Abstract: A fluorescent marker comprising inorganic fluorescent nanoparticles having on a surface of the nanoparticles a modifying group containing a reactive portion, wherein the reactive portion is located at a most remote site of the modifying group from the surface of the nanoparticles; the reactive portion comprises at least one selected from the group consisting of bases consisting of DNA or RNA, nucleotides, polynucleotides and intercalators; and the reactive portion is capable of specifically binding to a living organism.

Abstract: The present invention provide a semiconductor phosphor nanoparticle assembly which exhibits no variation in emission wavelength and emission intensity for every particle and is capable of achieving stable evaluation when performing a single molecule observation by using an assembly of semiconductor phosphor nanoparticles as a fluorescence labeling agent, a production method thereof and a single molecule observation method by use thereof. The production method of the semiconductor phosphor nanoparticle assembly, which is performed by a liquid phase process or a gas phase process, comprises the steps of forming nuclear particles and allowing the nuclear particles to grow or fuse, wherein a concentration by number of the formed nuclear particles is not more than a specific concentration.

Abstract: Disclosed are core/shell type semiconductor nanoparticles exhibiting a sufficient emission intensity without causing a blink phenomenon (blinking). The core/shell-type semiconductor nanoparticles have an average particle size of from 2 to 50 nm and comprise an intermediate layer between a core portion and a shell portion, wherein band gap widths of bulk crystals which have the same compositions as those of the core portion, the intermediate portion and the shell portion, respectively, are in the order of: core portion<shell portion<intermediate layer.

Abstract: A labeling fluorescent compound which enables highly stable detection in vital labeling and has high sensitivity. The labeling fluorescent compound is characterized by being composed of inorganic fluorescent nanoparticles which have a surface modification compound disposed on the surface thereof and have an average particle diameter of 1.0-20 nm. It is further characterized in that the proportion of the length of the surface modification compound as measured from the surface of the inorganic fluorescent nanoparticles to the particle diameter of the inorganic fluorescent nanoparticles is from 0.10 to 0.50, and that the proportion of the specific gravity of the inorganic fluorescent nanoparticles having the surface modification compound fixed thereto to the specific gravity of the inorganic fluorescent nanoparticles not having the surface modification compound is from 0.80 to 0.40.

Abstract: This invention provides a semiconductor nanoparticle aggregate comprising three or more types of semiconductor nanoparticles, which are different from each other in diameter, have a narrow particle size distribution, and are different from each other in maximum luminous wavelength of an emission spectrum in a wavelength region of 380 nm to 650 nm, a process for producing the semiconductor nanoparticle aggregate, and a biological substance labeling agent utilizing the semiconductor nanoparticle aggregate. The semiconductor nanoparticle aggregate comprises three or more types of semiconductor nanoparticles which have an identical chemical composition, are different from each other in particle diameter and fall within a particle diameter range of 1.8 to 4 nm and are different from each other in maximum luminous wavelength of an emission spectrum in a wavelength range of 380 to 650 nm.

Abstract: Disclosed is a fluorescent semiconductor microparticle assembly comprising at least three kinds of fluorescent semiconductor microparticles with an average particle size of from 1 to 10 nm, having the same chemical composition, a different average particle size and a different emission maximum wavelength in the emission spectra, wherein a standard deviation of emission intensity in each of the at least three kinds of fluorescent semiconductor microparticles is not more than 15%.

Abstract: A production method of nano-sized silicon crystal particles comprising the step of allowing monosilane to be oxidized in a bulk liquid phase to form the nano-sized silicon crystal particles within the bulk liquid phase, wherein a liquid of the bulk liquid phase is an unsaturated hydrocarbon free from an oxidizing gas; and isolating the nano-sized silicon crystal particles from the bulk liquid phase.

Abstract: A biomolecule detection reagent comprising a semiconductor nanoparticle aggregate, wherein each semiconductor nanoparticle, constituting the semiconductor nanoparticle aggregate, has detection molecules binding specifically with biomolecules on its surface, and a standard deviation of numbers of the detection molecules existing on each semiconductor nanoparticle, is 5% or less.

Abstract: Disclosed is a fluorescent semiconductor particle having a core/shell structure composed of a core particle as a semiconductor particle, and a shell layer by which the core particle is covered, wherein the core particle has a different chemical composition from that of the shell layer; the core particle has an average particle diameter of 1-15 nm and a specific gravity of 1.0-3.0; and the fluorescent semiconductor particle having the core/shell structure has a specific gravity of 0.8-3.

Abstract: An objective is to provide a nanosized semiconductor particle having a core/shell structure in which a ratio of shell thickness/core portion particle diameter exhibits an optimal ratio in optical properties of optical elements. The particle comprising the structure in which shell portion has a thickness of not more than 1/2 of core portion particle diameter, wherein core portion has a particle diameter of less than 20 nm, and shell portion has a thickness of at least 0.2 nm; core portion has a particle diameter of 20-100 nm, and shell portion has a thickness of at least 1/100 of a core portion particle diameter; core portion possesses at least one element of B, C, N, Al, Si, P, S, Zn, Ga, Ge, As, Se, Cd, In, Sb and Te; and shell portion has a composition exhibiting a larger band gap than that of core portion.