Abstract: A peptide nanofiber having conductivity is provided. A conductive peptide nanofiber which includes a nanofiber formed through a manner of self-assembly of a peptide that has a nanofiber-forming ability and consists of an amino acid sequence of Xaa-Phe-Ile-Val-Ile-Phe-Xaa (SEQ ID NO: 1, wherein N-terminal Xaa is an arbitrary amino acid residue Xaa1; C-terminal Xaa is an arbitrary amino acid residue Xaa2; and Xaa1 and Xaa2 are an amino acid having an acidic side chain, an amino acid having a basic side chain, or an amino acid having a side chain with polarity according as acidity and basicity) or a derivative of the peptide and a conductive substance added thereto, the aforementioned conductive substance being added to an amino group of the peptide or the derivative.

Abstract: Immobilization of malate dehydrogenase on a substrate using a glycerol solution containing malate dehydrogenase is achieved through dropping a mixed solution obtained by adding at least one selected from malic acid and malate to the glycerol containing malate dehydrogenase on the substrate, and drying it thereon. It is preferable to prepare the mixed solution by adding the malate to the glycerol solution containing malate dehydrogenase. The malate is preferably at least one selected from potassium malate and sodium malate.

Abstract: A device for detecting a physicochemical change in a biological sample comprising at least one measuring electrode provided by causing a conductive material to enter into a porous film, and a conductor connected to the measuring electrode.

Abstract: The present invention provides an apparatus for measuring activity signals of a biological sample comprising: a measurement chamber (A) storing a target liquid containing a biological sample; a porous insulating substrate (5) provided with a measurement electrode (1) on at least one side; and a conveying device (8) which conveys the target liquid stored in the measurement chamber (A) and passes the target liquid through the porous insulating substrate (5) from the measurement electrode (1) side, wherein the conveying device (8) is operated to trap the biological sample contained in the target liquid onto the measurement electrode (1), so that the activity signals of the biological sample are measured through the measurement electrode (1). According to the apparatus, activity signals emitted from the biological sample can be detected easily, rapidly and accurately.

Abstract: The present invention provides an apparatus for measuring activity signals of a biological sample comprising: a measurement chamber (A) storing a target liquid containing a biological sample; a porous insulating substrate (5) provided with a measurement electrode (1) on at least one side; and a conveying device (8) which conveys the target liquid stored in the measurement chamber (A) and passes the target liquid through the porous insulating substrate (5) from the measurement electrode (1) side, wherein the conveying device (8) is operated to trap the biological sample contained in the target liquid onto the measurement electrode (1), so that the activity signals of the biological sample are measured through the measurement electrode (1). According to the apparatus, activity signals emitted from the biological sample can be detected easily, rapidly and accurately.

Abstract: A multiple electrode includes a plurality of micro-electrodes provided on a substrate, and a wiring portion for providing an electrical signal to the micro-electrodes or extracting an electrical signal from the micro-electrodes. Each micro-electrode has porous conductive material on its surface, and the impedance of the micro-electrode is 50 k? or less. Preferably, the porous conductive material is gold, and formed by the passage of current at a current density of 1.0 to 5.0 A/dm2 for 10 to 360 sec. The multiple electrode may include micro-electrodes provided on a substrate in the form of a matrix, a lead line connected to the micro-electrodes, and an electrical junction connected to an end of the lead line.

Abstract: A peptide nanofiber having conductivity is provided. A conductive peptide nanofiber which includes a nanofiber formed through a manner of self-assembly of a peptide that has a nanofiber-forming ability and consists of an amino acid sequence of Xaa-Phe-Ile-Val-Ile-Phe-Xaa (SEQ ID NO: 1, wherein N-terminal Xaa is an arbitrary amino acid residue Xaa1; C-terminal Xaa is an arbitrary amino acid residue Xaa2; and Xaa1 and Xaa2 are an amino acid having an acidic side chain, an amino acid having a basic side chain, or an amino acid having a side chain with polarity according as acidity and basicity) or a derivative of the peptide and a conductive substance added thereto, the aforementioned conductive substance being added to an amino group of the peptide or the derivative.

Abstract: A sensor capable of simply and quickly measuring the electrical activities of a number of cells simultaneously and a device comprising the sensor and capable of detecting the signal transmission between subject cells are provided. The sensor comprises a plurality of electrodes provided on a substrate. The electrodes individually measure a signal generated by a biological sample held by each of the electrodes. Each of the electrodes comprises a depression for holding the biological sample, a throughhole which is in communication with the depression and penetrates to a rear side of the substrate, an electrode portion, and a drawing line from the electrode portion. The electrodes are arranged so that the samples held by the depressions electrically communicate with one another.

Abstract: A method for extracting a signal of interest from a signal generated from at least one subject, comprises the steps of (A) obtaining a time-series signal generated from the subject as a data group consisting of a plurality of pieces of data, (B) obtaining a plurality of extracted data groups from the data group, wherein each extracted data group comprises a predetermined number of pieces of data selected from the data group, (C) calculating standard deviations of the plurality of extracted data groups to obtain a standard deviation group, and (D) referencing each standard deviation included in the standard deviation group and selecting the signal of interest.

Abstract: A multiple electrode for measuring electro-physiological characteristics of a biological specimen includes a plurality of micro-electrode provided on a first region on a substrate, and a reference electrode provided in a second region on the substrate. The reference electrode includes at least one stimulus reference electrode for applying an electrical signal to the plurality of micro-electrodes. Preferably, the reference electrode includes at least one measurement reference electrode for detecting an electrical signal from the plurality of micro-electrodes, and the stimulus reference electrode is electrically insulated from the measurement reference electrode. Preferably, the second region is placed at a distance from an outer edge of the first region, and surrounds the first region.

Abstract: A method of measuring the physical and chemical properties of tissue or cells and a device for the same is provided, with which the physical and chemical environment of the tissue or cells can be changed arbitrarily corresponding to experimental necessities. The device comprises a system 40 for keeping the physical and chemical environment surrounding the biological tissue or cells constant, a system 50 for arbitrarily changing the physical and chemical environment, observation systems 10 and 20 for observing the physical and chemical properties of the tissue or cells, and a system 30 for comparing the change of the physical and chemical properties of the tissue or cells before and after changing the physical and chemical environment. The observation system 10 is a potential measurement device for measuring the electrophysiological properties of the tissue or cells.

Abstract: A measurement device 10 includes a measurement cell 11. The measurement cell 11 includes a substrates 17 and a substrate 16 formed on the substrate 17. The substrates 16 and 17 are bonded to each other. Thus, a flow pass 9 is formed in the measurement cell 11. As shown in FIG. 3, on the substrate 17 of the measurement cell 11, provided are a concave well 19, a protruding microelectrode 1 connected to a terminal 4a and formed on a side wall surface of the well 19, communicating tubes 15a and 15b connected to both of side surfaces of the well 19 (i.e., the flow pass 9) to face to each other, resistance baths 6a and 6b connected to the communicating tubes 15a and 15b, thin film resistors 3a and 3b arranged in the resistance baths 6a and 6b, and a reference electrode 2 connected to a terminal 4b.

Abstract: A sensor capable of simply and quickly measuring the electrical activities of a number of cells simultaneously and a device comprising the sensor and capable of detecting the signal transmission between subject cells are provided. The sensor comprises a plurality of electrodes provided on a substrate. The electrodes individually measure a signal generated by a biological sample held by each of the electrodes. Each of the electrodes comprises a depression for holding the biological sample, a throughhole which is in communication with the depression and penetrates to a rear side of the substrate, an electrode portion, and a drawing line from the electrode portion. The electrodes are arranged so that the samples held by the depressions electrically communicate with one another.

Abstract: This invention relates to methods for the detection and characterization of psychoactives in neuronal tissue by comparing parameters measured for a set of baseline oscillations with those same parameters measured for a set of resulting oscillations. The baseline oscillations are induced or stimulated by such agents as chemical compounds that effect cholinergic interactions, co-deposited neuronal tissue, or electrical stimulations. The resulting set of oscillations is obtained after exposing the neuronal tissue to a sample composition that may or may not contain a psychoactive. By comparing the parameters for the baseline and resulting oscillations, the psychoactive in the sample composition may be detected and characterized as belonging to a specific psychoactive compound class and in some instances, may be distinguished from other members of the psychoactive compound class.

Abstract: The present invention provides an apparatus for measuring activity signals of a biological sample comprising: a measurement chamber (A) storing a target liquid containing a biological sample; a porous insulating substrate (5) provided with a measurement electrode (1) on at least one side; and a conveying device (8) which conveys the target liquid stored in the measurement chamber (A) and passes the target liquid through the porous insulating substrate (5) from the measurement electrode (1) side, wherein the conveying device (8) is operated to trap the biological sample contained in the target liquid onto the measurement electrode (1), so that the activity signals of the biological sample are measured through the measurement electrode (1).

Abstract: The method for detecting a target nucleic acid includes the steps of: preparing a nucleic acid probe labeled with a donor fluorescent substance and an acceptor substance placed to allow occurrence of fluorescence energy transfer, the nucleic acid probe having a sequence complementary to at least part of the target nucleic acid; mixing a sample solution with the nucleic acid probe to hybridize the target nucleic acid and the nucleic acid probe; and after the step of mixing, allowing the sample solution to act with sequence-independent nuclease and detecting the target nucleic acid from a change in the fluorescence intensity of the sample solution. This enables both enhancement of the degree of freedom in the design of the nucleic acid probe and simplification of the operation.

Abstract: A method for extracting a signal of interest from a signal generated from at least one subject, comprises the steps of (A) obtaining a time-series signal generated from the subject as a data group consisting of a plurality of pieces of data, (B) obtaining a plurality of extracted data groups from the data group, wherein each extracted data group comprises a predetermined number of pieces of data selected from the data group, (C) calculating standard deviations of the plurality of extracted data groups to obtain a standard deviation group, and (D) referencing each standard deviation included in the standard deviation group and selecting the signal of interest.

Abstract: A multiple electrode includes a plurality of micro-electrodes provided on a substrate, and a wiring portion for providing an electrical signal to the micro-electrodes or extracting an electrical signal from the micro-electrodes. Each micro-electrode has porous conductive material on its surface, and the impedance of the micro-electrode is 50 k&OHgr; or less. Preferably, the porous conductive material is gold, and formed by the passage of current at a current density of 1.0 to 5.0 A/dm2 for 10 to 360 sec. The multiple electrode may include micro-electrodes provided on a substrate in the form of a matrix, a lead line connected to the micro-electrodes, and an electrical junction connected to an end of the lead line.

Abstract: A cell potential measurement apparatus, which uses a planar electrode enabling a multi-point simultaneous measurement of potential change arising from cell activities, is provided which can conduct measurements accurately and efficiently as well as can improve convenience of arranging measurement results.

Abstract: A cell potential measurement apparatus, which uses a planar electrode enabling a multi-point simultaneous measurement of potential change arising from cell activities, is provided which can conduct measurements accurately and efficiently as well as can improve convenience of arranging measurement results.