Abstract: The invention is to easily detect an interaction between nucleic acid and protein with high sensitivity without the need of sample labeling with a fluorescent molecule or sample anchorage onto a metal thin-film. As means for it, the presence or absence of occurrence of the interaction between nucleic acid and protein in a sample (S) is detected in an optical manner. Specifically, the sample (S) is irradiated with excitation rays (Le) and with measuring rays (L2) for measuring a photothermal effect produced in the sample (S) through the irradiation with the excitation rays (Le). A measurement signal for the photothermal effect in the sample (S) by the excitation rays (Le) is produced on the basis of any phase change of the measuring rays (L2). A temporal variation in the measurement signal is used for making a judgment on the presence or absence of any occurrence of interaction between nucleic acid and protein.

Abstract: A method for measuring a test substance whereby the test substance in a sample can be specifically measured without using an antibody against the test substance; an aptamer molecule used therefor; and a method for creating the aptamer are disclosed. An aptamer capable of hybridizing with an oligonucleotide when it is bound to a test substance, but is incapable of hybridizing with the oligonucleotide when it is not bound to the test substance, is utilized. The aptamer is brought into contact with a sample, and the aptamer bound to the test substance is brought into contact with an immobilized oligonucleotide which hybridizes with the aptamer, to bind the aptamer to a solid phase, followed by measurement of the aptamer immobilized on the solid phase.

Abstract: Disclosed are a method for assaying a target substance in a sample and an apparatus for the method. The method can specifically assay the target substance in the sample without using any antibody against the target substance. The assaying method includes simultaneously or successively bringing a labeled aptamer, the target substance in the sample and a solid phase into contact together, and then measuring the label of the aptamer which has not been bound on the solid phase. The labeled aptamer has a property of binding to the target substance. The solid phase carries an oligonucleotide immobilized on it in an excess amount relative to the target substance. The oligonucleotide is hybridizable with the labeled aptamer when the labeled aptamer is in a state that it is not bound to the target substance, but is not hybridizable with the labeled aptamer when the labeled aptamer is in a state that it is bound to the target substance.

Abstract: The present invention relates to a labeling enzyme and a method of detecting and/or quantifying a target substance using this labeling enzyme. The present invention provides a labeling enzyme that catalyzes a reaction of gelling a substrate. By measuring changes in physical properties such as the film thickness and/or refractive index of a film produced by the gelling reaction catalyzed by the labeling enzyme of the present invention, it is possible to quickly and highly sensitively detect and/or quantify a target substance while minimizing the effects of coexisting substances.

Abstract: An aptamer-probe complex for detecting the presence of a target molecule is disclosed. The complex of the present invention contains an aptamer moiety which is able to bind to an indicator protein and change the properties of the indicator protein, and a probe moiety which is able to bind to a target molecule, wherein the aptamer moiety and the probe moiety are combined in such a manner that the binding mode between the aptamer moiety and the indicator protein changes when the probe moiety binds to the target molecule. A target molecule can be detected with combination of an aptamer which binds to a certain protein, and a probe which binds to the target molecule, utilizing the properties of that protein as an indicator.

Abstract: The present invention aims to achieve a chip having a construction in which each film of metal, dielectric, and fluorescent material is stacked on a glass substrate 1. Such a construction can enhance the intensity of fluorescence emitted from a fluorescent material owing to the interaction between the fluorescent material and the light propagation mode in that construction.

Abstract: The present invention aims to achieve a chip having a construction in which each film of metal, dielectric, and fluorescent material is stacked on a glass substrate 1. Such a construction can enhance the intensity of fluorescence emitted from a fluorescent material owing to the interaction between the fluorescent material and the light propagation mode in that construction.