Abstract: A semiconductor nanoparticle assembly including semiconductor nanoparticles having a core/shell structure, and wherein the semiconductor nanoparticles are bonded by means of amide bonds.

Abstract: The present invention provides a biological substance detection method for specifically detecting a biological substance from a pathological specimen, by which method, when immunostaining using a fluorescent label and staining for morphological observation using a staining agent for morphological observation are simultaneously performed, the results of fluorescence observation and immunostaining can be assessed properly even if the fluorescent label and/or the staining agent is/are deteriorated by irradiation with an excitation light. The biological substance detection method according to the present invention is characterized in that the brightness retention rate of an immunostained part is in a range of 80% to 120% in relation to the brightness retention rate of apart stained for morphological observation when the fluorescent label used for the immunostaining is observed.

Abstract: The present invention provides a fluorescent label that can be used for carrying out a biological substance detection method for specifically detecting a biological substance from a pathological specimen, by which method, when immunostaining using a fluorescent label and staining for morphological observation using a staining agent for morphological observation are simultaneously performed, the results of fluorescence observation and immunostaining can be assessed properly even if the fluorescent label and/or the staining agent is/are deteriorated by irradiation with an excitation light. The fluorescent label is a fluorescent dye-containing nanoparticle in which the parent material is a cross-linked polymer and the fluorescent dye is an aromatic ring-based dye molecule. The cross-linked polymer is suitably a melamine resin or a styrene resin. The aromatic ring-based dye molecule is suitably a perylene and more suitably a perylene diimide.

Abstract: A biological substance detection method for detecting a biological substance specifically in a pathological specimen, comprising a step of immunologically staining the pathological specimen using a fluorescent label, a step of staining the pathological specimen with a staining reagent for morphology observation purposes (eosin) to observe the morphology of the pathological specimen, a step of irradiating the stained pathological specimen, with excited light to cause the emission of a fluorescent and detecting the biological substance in the pathological specimen. In the step of immunologically staining the pathological specimen, a special fluorescent particle for which the excitation wavelength appears in a region that is different from the excitation wavelength region of eosin is used as the fluorescent label.

Abstract: A semiconductor nanoparticle assembly including semiconductor nanoparticles having a core/shell structure, and wherein the semiconductor nanoparticles are bonded by means of amide bonds.