Matsushita Electric Industrial Co., Ltd.

Other

Matsushita Technical Information Services Co., Ltd.

Makoto Taketani

Hirokazu Sugihara

Tadayasu Mitsumata

Akihito Kamei

Yasushi Kobayashi

Hiroshi Iwasaki

Hiroaki Oka

Jinsei Miyazaki

Ryuta Ogawa

Ken Shimono

Gary S Lynch

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. According to the configuration of the cell potential measurement apparatus of this invention, it includes an integrated cell holding instrument, which includes a planar electrode provided with a plurality of microelectrodes arranged in a matrix form on the surface of a substrate, a cell holding part for placing cells thereon, drawer patterns from the microelectrodes, and electric contact points for outside connections; an optical observation means for optical observations of cells; a stimulation signal supply means to be connected to the cell holding instrument for providing electric stimulation to the cells; and a signal processing means to be connected to the cell holding instrument for processing an output signal arising from electric physiological activities of the cells. It is preferable that a cell culturing means is also provided for maintaining a culture atmosphere of the cells placed on the integrated cell holding instrument.

Cell potential measurement apparatus having a plurality of microelectrodes

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 systemfor keeping the physical and chemical environment surrounding the biological tissue or cells constant, a systemfor arbitrarily changing the physical and chemical environment, observation systemsandfor observing the physical and chemical properties of the tissue or cells, and a systemfor 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 systemis a potential measurement device for measuring the electrophysiological properties of the tissue or cells. This device comprises an integrated cell placement deviceprovided with a plurality of microelectrodeson a substrate, a cell placement portionfor placing the tissue or cells on the microelectrodes, and a wiring patternfor applying an electrical signal to the microelectrodesand extracting an electrical signal from the microelectrodes

Method for measuring physiocochemical properties of tissues of cells, method for examining chemicals, and apparatus therefor

This relates to methods for the detection of psychoactive compounds in an in vitro neuronal tissue sample by detecting oscillations of extracellular voltage desirably before and after the introduction of a candidate sample onto an in vitro neuronal tissue sample and for devices useful in practicing the methods. Analysis of the extracellular voltage parameters leads to indication of the presence of psychoactive material in the candidate sample and information as to its pharmacological activity and/or composition. Further, it relates to a process of initiating and maintaining the presence of repetitive neuronal activity within the in vitro sample. Additionally, this includes a method for the stimulation of or initiation of repetitive neuronal activity, e.g., EEG, in an in vitro neuronal tissue sample by introducing a stimulating composition comprising compounds that facilitate or mimic the actions of acetylcholine, serotonin, or catecholamines, such as carbachol, or by subjecting the in vitro neuronal sample to electrical stimulation parameters.

Methods and device for in vitro detection and characterization of psychoactives using analysis of repetitive electrical activity in a neuronal sample

A method of observing a physical and chemical property of a tissue or cell by using an apparatus which comprises at least a cell culturing means, an environment conditioning means, an observing means and a comparing means, comprising the steps of (A) culturing the tissue or cell by the cell culturing means, (B) maintaining a first physical and chemical environment around the tissue or cell by the cell culturing means, (C) observing a first physical and chemical property of the tissue or cell in the first physical and chemical environment by the observing means, (D) changing the first physical and chemical environment to a second physical and chemical environment by the environment conditioning means, (E) observing a second physical and chemical property of the tissue or cell in the second physical and chemical environment by the observing means, and (F) comparing the first physical and chemical property of the tissue or cell with the second physical and chemical property of the tissue or cell by the comparing means.

Measurement of complete electrical waveforms of tissue or cells

A two-dimensional sensor is described including a substrate having a Si layer, a SiO,layer and a Si,N,layer. On the surface of the Si back side, a thin film is formed by vapor deposition for making an effect electrode. On the surface of the Si,N,front side, a fence is attached for containing a sample cell, culture medium and a reference electrode. This sensor is placed in an incubator and a bias voltage is applied between the effect and reference electrodes. When a high frequency modulated laser beam irradiates a spot on the back side of the sensor substrate, a signal of AC photocurrent is obtained from the effect electrode. This signal corresponds to a potential alteration due to the cell activity substantially at the spot. The signal is processed in a computer. Therefore, the beam spot size and location, corresponding to the size and the location of the measurement electrode, can be adjusted easily by focusing or moving the laser beam.

Two-dimensional sensor using laps for measuring cell activity

A two-dimensional sensor includes a photoconductive layer whose conductivity increases at a light-irradiated spot, an insulating layer formed on the front surface of the photoconductive layer, an effect electrode formed on the back surface of the photoconductive layer, and a fence as a cell holder attached to the surface of the insulating layer for containing a cell, culture medium and a reference electrode. The sensor is placed in an incubator and a bias voltage is applied between the effect and reference electrodes. When a laser beam irradiates a spot of the back surface of the sensor, a signal is obtained from the effect electrode. This signal corresponds to a potential alteration due to the cell activity substantially at the laser-irradiated spot. The signal is processed in a computer. The beam spot size and location, corresponding to the size and the location of the measurement electrode, can be changed or adjusted easily by focusing or moving the laser beam.

Two-dimensional sensor having photoconductive layer for measuring cell activity

A planar electrode which enables multi-point simultaneous stimulation and recording of nerve cells over a long time is provided, which also has excellent response property. An ITO film is evaporated on the whole surface of an insulating substrate of the hard glass, and the ITO film is etched so that the central portion of each electrode is located on each intersection of 8.times.8 lattices, the center-to-center distances of nearest electrodes of each electrode are equal, and a lead wire is stretched radially. Then, for an insulating layer, negative photo-sensitive polyimide is spin-coated, and an insulating layer pattern is exposure-formed so that a 50 .mu.ms square hole is produced at the center of each electrode. Furthermore, to the exposed portion of each electrode (that is, the inside of the 50 .mu.ms square), Ni is evaporated in a film thickness of 500 nm, which is followed by evaporating gold (50 nm) and platinum black (about 1 .mu.m). The contact with the external circuit of the section near the end opposite to the electrode of the lead wire was coated with gold and nickel.

Planar electrode

This invention relates to a low impedance cell potential measuring electrode assembly typically having a number of microelectrodes on an insulating substrate and having a wall enclosing the region including the microelectrodes. The device is capable of measuring electrophysiological activities of a monitored sample using the microelectrodes while cultivating those cells or tissues in the in the region of the microelectrodes. The invention utilizes independent reference electrodes to lower the impedance of the overall system and to therefore lower the noise often inherent in the measured data. Optimally the microelectrodes are enclosed by a physical wall used for controlling the atmosphere around the monitored sample.

Cell potential measuring electrode and measuring apparatus using the same

A planar electrode which enables multi-point simultaneous stimulation and recording of nerve cells over a long time is provided, which also has excellent response property. An ITO film is evaporated on the whole surface of an insulating substrate of the hard glass, and the ITO film is etched so that the central portion of each electrode is located on each intersection of 8.times.8 lattices, the center-to-center distances of nearest electrodes of each electrode are equal, and a lead wire is stretched radially. Then, for an insulating layer, negative photo-sensitive polyimide is spin-coated, and an insulating layer pattern is exposure-formed so that a 50 .mu.ms square hole is produced at the center of each electrode. Furthermore, to the exposed portion of each electrode (that is, the inside of the 50 .mu.ms square), Ni is evaporated in a film thickness of 500 nm, which is followed by evaporating gold (50 nm) and platinum black (about 1 .mu.m ). The contact with the external circuit of the section near the end opposite to the electrode of the lead wire was coated with gold and nickel.

Cell potential measurement apparatus having a plurality of

A N-(4-aminobutyl)amphetamine-protein complex has been synthesized to be used as an immunogen to prepare an antibody having a higher affinity to methamphetamine that to the hapten N-(4-aminobutyl)amphetamine. The antibody prepared by the use of the complex has 1,000 times the affinity to methamphetamine as that of an antibody prepeared by the use of N-(4-aminobutyl)methamphetamine-protein complex as an immunogen.

Amphetamine protein complex as immunogen for obtaining antibodies

A N-(4-aminobutyl)amphetamine-protein complex has been synthesized to be used as an immunogen to prepare an antibody having a high affinity to methamphetamine. The antibody prepared by the use of the complex has 1,000 times the affinity to methamphetamine as that of an antibody prepared by the use of N-(4-aminobutyl)methamphetamine-protein complex as an immunogen.

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Kyoto, Japan

Makoto Taketani