Abstract: An object of the present invention is to provide a method for detecting a target nucleotide sequence using the hybridization method, which has a remarkably improved sensitivity of detection. The method comprises the steps of hybridizing a target nucleotide sequence with a PNA that is complementary to the whole or a part of the target nucleotide sequence and measuring the degree of hybridization at the presence of a denaturing agent.

Abstract: The present invention provides a differential SPR sensor that is capable of independently determining resonance wavelenghts without determining a baseline. A differential SPR sensor is formed with a surface immobilized with a recognition component and a surface not immobilized with the component on a metal film. The sensor comprises a plurality of dielectric films of different film thicknesses formed on the metal film, wherein one of said dielectric films is taken to be a reference surface and at least the other one dielectric film is taken to be a working surface immobilized with the recognition component. Preferably, the sensor is a probe-type SPR sensor, and a working surface and a reference surface are formed on a metal film providing a sensor surface of the probe.

Abstract: An apparatus for automatically measuring minute membrane potential, based on a technique developed for controlling a membrane denaturation reaction without using a physical shearing force, for example, a method of causing the destruction of membrane at a limited portion of a living membrane by making a stimulus, such as light and a compound activated by the stimulus react with each other in a membrane, such as a living membrane, this method being applied to a minute electrode to facilitate the insertion thereof into a cell, which has been difficult in the use of a minute metal electrode, and enable membrane potential in a cell to be measured easily, the minute metal electrode enabling the integration thereof and the development of a neural interface in the barrier-free technology.

Abstract: An object of the present invention is to provide a method for detecting a target nucleotide sequence using a complementary nucleotide sequence that has an excellent sensitivity of detection. The method comprises the steps of converting the target nucleotide sequence to a partially double-stranded nucleotide sequence which is double-stranded at one part and single-stranded in the remaining part and detecting said partially double stranded nucleotide sequence using a nucleotide sequence that is complementary to the target nucleotide sequence.

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.

Abstract: An object of the present invention is to provide a method for detecting a target nucleotide sequence using a complementary nucleotide sequence that has an excellent sensitivity of detection. The method comprises the steps of converting the target nucleotide sequence to a partially double-stranded nucleotide sequence which is double-stranded at one part and single-stranded in the remaining part and detecting said partially double stranded nucleotide sequence using a nucleotide sequence that is complementary to the target nucleotide sequence.

Abstract: A method for assaying a nucleic acid comprising amplifying a nucleic acid in a sample by gene amplification and measuring the increased amount of the nucleic acid by a fluorescence polarization technique, in which the gene amplification is carried out by asymmetric amplification, or annealing with the primers used in the amplification is carried out after amplification of the nucleic acid, thereby to facilitate binding of a fluorescence-labeled reagent to the target single-stranded nucleic acid.

Abstract: A method for assaying a nucleic acid comprising amplifying a nucleic acid in a sample by gene amplification and measuring the increased amount of the nucleic acid by a fluorescence polarization technique, in which the gene amplification is carried out by asymmetric amplification, or annealing with the primers used in the amplification is carried out after amplification of the nucleic acid, thereby to facilitate binding of a fluorescence-labeled reagent to the target single-stranded nucleic acid.

Abstract: The microbial electrode is constructed having a substrate(3) made of an insulating material, an electric conductor(2) which is fixed on the substrate and a membrane containing microorganism cells(1) which is fixed on the conductor. The microbial sensor(20) is constructed having the microbial electrode above described and a conductor(11) to act as a counter electrode fixed on the insulating material of the surface of the substrate of the electrode which is opposite to the surface where the membrane containing microorganism cells is fixed.

Abstract: An enzyme sensor system capable of quantitatively determining a particular component contained in a biological sample in a rapid and easy manner is disclosed. More particularly, an electrically conductive enzyme, an enzyme-immobilized electrode using the same and a composition for use in the preparation of the enzyme electrode are disclosed. The composition for an enzyme-immobilized electrode according to the present invention enables electrodes of various patterns to be produced by screen printing.

Abstract: The present invention is a method of producing an oligosaccharide of a higher polymerization degree by enzymatic hydrolyzing of a polysaccharide with a hydrolase capable of cleaving the bonds among sugars constituting the polysaccharide comprising step of making the polysaccharide coexist with the hydrolase in a mixture of water and a hydrophilic organic solvent such as ethanol.

Abstract: The present invention; is a method of producing .beta.-cyclodextrin at a higher efficiency from a raw material other than starch, comprising making a malto-oligosaccharide with 2 to 10 glucoses co-exist with cyclodextrin glucanotransferase in a solution containing an organic solvent which can precipitate 50% or more of .beta.-cyclodextrin when an excessive amount of the solvent is added to the solution of the .beta.-cyclodextrin and effecting the reaction at a lower temperature than 40.degree. C.

Abstract: Chitin-containing material is heat-treated in organic solvent or in the solvent with water, and then .beta.-1, 4 glycoside decomposing enzyme is added for decomposing the chitin-containing material by enzyme reaction. Or, chitin-containing material is ultrasonicated in organic solvent or in the solvent with water, and then chitin-containing material is decomposed by enzyme reaction of .beta.-1, 4 glycoside decomposing enzyme. Further, chitin-containing material is exposed in the solution containing urea and/or surfactant, and then chitin-containing material is let co-exist with .beta.-1, 4 glycoside decomposing enzyme under the presence or non-presence of urea and/or surfactant for decomposing chitin-containing material. Or, at the time of exposing chitin-containing material in the solution containing urea and/or surfactant, the solution is heated and the .beta.-1, 4 glycoside decomposing enzyme is added for decomposing chitin-containing material.

Abstract: A viscosity measuring system comprises a cell containing gelable liquid and a piezoelectric resonator mounted in the cell. The piezoelectric resonator has a prescribed characteristic, such as electrical resistance or resonant frequency, which varies in accordance with the gelating of the liquid. Solid particles suspended in the liquid are deposited on the piezoelectric resonator during gelating of the liquid to amplify the prescribed resonator characteristic. A measuring circuit measures the variation of the resonator characteristic to thereby determine the gelation time of the liquid.

Abstract: A bio-thermo sensor has an enzyme-modified membrane directly supported on an IC thermal detector in face-to-face contact. The enzyme-modified membrane selectively reacts with a specific chemical substance to generate therein a reaction heat which is converted into an amplified output voltage indicative of the chemical substance by the IC thermal detector. The IC thermal detector includes Darlington-connected transistors which provide high sensitivity and quick response time.

Abstract: Miniaturized Clark-type oxygen electrodes includes a substrate having at least one recess groove formed on a surface thereof for receiving an electrolyte solution, and two electrodes acting as a cathode and an anode formed through an insulating layer on the surface of the substrate. Each of the electrodes is at least partially disposed in a bottom area of the recess. A solid or semi-solid, porous, electrolyte solution-containing material fills the recess, and an oxygen gas-permeable membrane covers and seals the recess and porous material received therein. Miniaturized biosensors are made using the oxygen electrode as a transducer. The oxygen electrodes and biosensors, which are extremely accurate, can be mass-produced and can be widely used in various fields such as clinical analysis, industrial processing, and in the determination of environmental conditions. The biosensors can be particularly used in clinical diagnosis and in monitoring devices for both in vivo and in vitro measurements.

Abstract: A bio-sensor is mounted in a container and comprised of a receptor for selectively reacting with a specific biochemical substance in a sample liquid held in the container to bind thereon the specific biochemical substance and a resonator integrated with the receptor for detecting the amount of the specific biochemical substance bound to the receptor in terms of a resonant frequency shift of the resonator. A measuring circuit is connected to the sensor for measuring the resonant frequency shift of the resonator within the container; a switching valve operates during the reaction of the receptor with the specific biochemical substance to charge a sample liquid into the container to contact the sample liquid with the receptor to thereby effect the reaction and operates during the measurement of the resonant frequency shift to replace the sample liquid by a buffer liquid in the container to immerse the sensor in the buffer liquid to thereby prevent a fluctuation of the resonant frequency shift.

Abstract: Electrochemical method for determining the concentration of a carbon source and L-amino acid in a fermentation medium or cultured broth by contacting a microbial electrode consisting of an oxygen-sensitive electrode or a carbon dioxide gas-sensitive electrode combined with fixed microbial cells of a microorganism capable of assimilating said carbon source or decarboxylating said L-amino acid with a sample solution and sensing electrically the rate of current decrease which is caused by the consumed oxygen in the solution in proportion to the concentration of carbon source; or the electric motive force which is caused by the liberation of carbon dioxide in the sample solution in proportion to the concentration of L-amino acid. Microbial electrodes and systems useful in carrying out the aforementioned method are disclosed.

Abstract: The biochemical oxygen demand (BOD) of an aqueous liquid contaminated with organic matter is determined by contacting a sample solution with elementary oxygen and with immobilized microorganisms capable of aerobically metabolizing the organic matter and of thereby consuming the oxygen. The rate of oxygen consumption under otherwise uniform conditions is as precise a measure of BOD as the conventional five-day test, but is determined within less than two hours, usually less than 30 minutes. A membrane-type oxygen-sensitive electrode is employed for sensing the rate of oxygen consumption and generates an output signal which is readily correlated with the BOD of the tested liquid.