Abstract: A compact non-reciprocal circuit device capable of handling a high power without impairment of the characteristics. The non-reciprocal circuit device contains a magnetic substrate that exhibits anisotropic behavior by application of a direct-current magnetic field. On the surface of the substrate, strip-lines are disposed at an angle, being insulated with each other. One end of each strip-line is grounded, and the other end of each is connected through a capacitor to a ground. Of the ends connecting the capacitors, one end connects to a termination resistor; the remaining ends connect each to an input terminal and an output terminal. The non-reciprocal circuit device exhibits non-reciprocal characteristics between the input and output terminals. The case of the device contains an insulating thermal conductor that serves as a heat-radiator for the termination resistor and the strip-lines.

Abstract: Methods for detecting target DNA's in a sample on the basis of oscillation frequency using nucleic acid sequences immobilized to the surface of an electrode of an elastic wave element, and DNA sensors for conducting the methods are described. These methods provide for highly sensitive detection of target DNA's in a sample.

Abstract: In the manufacture of a substrate with a hydrophobic film used for a reference electrode of an ion sensor or the like, a hydrophobic film is formed on a substrate by irradiating a target consisting of a hydrophobic compound with a neutral atom beam and thereby effecting sputtering. The apparatus for effecting the sputtering comprises a target base disposed in a vacuum chamber, an atom beam gun for irradiating a target on the target base with a neutral beam, a substrate base and a shutter for controlling the passage of sputtered particles. A thin film that is manufactured is suitable for an ion sensor, such as an ISFET or the like or an enzyme sensor.

Abstract: A reference electrode for generating a reference potential on an ion sensor is disclosed. The reference electrode has a lamination film covering a surface of an electrically conductive substrate and formed by alternately laminating silver halide thin films and hydrophobic resin thin films.

Abstract: An enzyme sensor is disclosed, which has a two-layer fixed film structure consisting of a reduction function layer including an electron movement medium and di-valent iron ions and an enzyme-fixed layer covering said reduction function layer, and in which hydrogen peroxide generated through decomposition of glucose or the like in the enzyme-fixed layer is reduced by electron movement medium and di-valent iron ions in the reduction function layer.Thus, the construction of enzyme sensor is simplified, measurement is extremely facilitated, and the measurement time is reduced.As a different principle of enzyme sensor, an electrically conductive substrate of conductive carbon or the like is covered with an oxygen-reducing catalytic function layer and enzyme layer.Thus, there is no problem of contamination of enzyme sensor, and it is possible to readily manufacture and miniaturize enzyme sensors.

Abstract: A reference electrode according to the present invention includes a silver layer (2) and an insulating hydrophobic material layer (5) which is formed by atomic beam sputtering and containing silver halide dispersed therein, on the surface of a conductive substrate (1).The resulting reference electrode is of a solid type, is almost free from outflow of silver halide, can be miniaturized easily, is not affected by ion concentration, provides a stable potential and has high durability.The conductive substrate (1) may be a field effect transistor having a gate insulator film and the layer (5) may be a laminate film obtained by laminating alternately a thin layer or layers of silver halide and a thin layer or layers of insulating hydrophobic material.

Abstract: The present invention provides an ion sensitive film (6) comprising a mixed layer containing a redox manifesting substance manifesting redox function and a polymeric compound containing an ion carrier substance. The present invention also provides a method of producing the ion sensitive film (6) and an ion sensor which uses the film (6). The ion sensitive film (6) of the present invention enables the provision of an ion sensor having excellent durability, preservative stability and sensor characteristics.

Abstract: A film-coated sensor is formed by providing an electrically conductive substrate (2), which has a sectional area of less than 10.sup.-5 cm.sup.2, connected to a lead wire (5) at one end of an insulative capillary (1) and inscribed in the capillary (1), and providing a coating film (7) at another end, which is open, of the capillary (1) by an electrolytic polymerization process.The film-coated sensor obtained has a surface which is uniform, the film coating is easy to control, and since the sensor is not readily susceptible to flow of a specimen fluid, there is little drift and response is quick. Owing to its small size, the sensor is capable of measuring very small samples and of performing measurement upon being directly inserted into a living body or tissue.The sensor can be used also as an enzyme sensor by coating the surface of the film-coated sensor with a fixing enzyme film.

Abstract: A portion of a board (1) on which copper wiring is printed is provided with a carbon coating, the board (1) and lead wires (2) are joined by solder (3), the portion having the solder (3) is insulated with a silicone resin (4), and the carbon-coated printed wiring portion (10a) is successively coated with a redox layer (11) obtained by electro-oxidation of 2,6 xylenol and an ion-selective layer (12), thereby forming an ion sensor (20).Since the ion sensor can be formed on a printed wiring board, various devices which include an ion sensor can readily be fabricated on a board.

Abstract: An electrochemical cell is formed by immersing an electrochemical ion sensor and a reference electrode into a solution of interest, the electrochemical ion sensor exhibiting ion selectivity with respect to an ion of interest and having a high electrode resistance. A current which flows through the electrochemical cell is measured while the potential of the electrochemical ion sensor is held to a constant potential with respect to the reference electrode. The current so obtained are proportional to the logarithm value of the concentration of the ion.

Abstract: An ion sensor of the type wherein a specific type of ion in an aqueous solution is measured by potential response. The sensor includes a conductor base, and a reversible redox polymer film formed directly on a surface of said conductor base. An ion carrier film is formed directly on a surface of said redox polymer film. The carrier film contains an ion carrier substance for allowing the specific type of ions to permeate from the aqueous solution to said polymer film.

Abstract: A biological information measurement apparatus is adapted to measure biological information in an extracorporeal circuration or in a living body by various measurement circuits comprising circuit elements which are not affected by electrical disturbances, and to transmit the results of measurement in the form of a non-electrical signal which is not affected by electrical disturbances. Measured values from measurement sections are gathered at a central processing section separated from the measurement sections. The processing section converts the measured values into output values, compensates the values for temperature and outputs the values to a display unit and recorder.

Abstract: The surface of an electrically conductive substrate (1) is provided with a redox layer (5) by an electrolytic polymerization process, and the surface of the resulting member is further provided with an ion carrier membrane (6) which includes polyvinyl chloride, a plasticizer and an ion carrier, thereby forming an ion sensor. Used as the plasticizer is one selected from among phthalate plasticizers, maleate plasticizers, adipate plasticizers, carboxylate plasticizers and polycaprolactone plasticizers, or one selected from among plasticizers comprising modified ethylene-- vinyl acetate copolymer. The ion sensor obtained has low solubility in the plasticizer of the redox layer and therefore is highly stable. Since the ion sensor has little toxicity, it can be used in vivo.

Abstract: A miniature, solid-state long-life reference electrode in which the amount of outflow of an internal electrolyte containing a halogen ion is reduced includes a conductor on the periphery of which is formed a sintered body consisting of a silver halide and silver oxide, a water-containing gel enveloping the conductor and including a halogen ion electrolyte, and a hollow tubular body closed by a liquid-junction portion comprising a porous ceramic, or by a partitioning wall having an ion permeable portion of a predetermined diffusion coefficient and volume. In another embodiment, the tubular body of the reference electrode is partitioned by a partitioning wall having an ion permeable portion of a predetermined diffusion coefficient and volume.

Abstract: A reference electrode for generating a reference potential on an ion sensor is disclosed. The reference electrode has a lamination film covering a surface of an electrically conductive substrate and formed by alternately laminating silver halide thin films and hydrophobic resin thin films.

Abstract: The surface of a gate insulating membrane of an ion-selective field-effect transistor (ISFET) (10) is coated with a carbon thin membrane (4), and the surface of the latter is coated with an electrolytic polmerization membrane (3) of 2,6 xylenol. The ISFET obtained exhibits hydrogen-ion selectivity, little drift, high stability and little response to light. If the surface of the electrolytic polmerization membrane (3) of 2,6 xylenol is coated with another ion-selective membrane or enzyme-active membrane, various ions and the concentration of a biological substrate can be measured.

Abstract: A functional elemental device and an FET sensor provided with the same, formed by forming a conductive carbide layer between the substrate and a conductive carbon material layer, and organic thin films and were formed on the surface of said conductive carbon material layer.Thereby, the adhesiveness between the substrate and the conductive carbon material layer can be remarkably improved, and peeling does not occur in the case of electrolytic polymerization reaction and film formation, and since the interstitial ions and the like from the substrate can be prevented, the lowering of the function can be prevented, and therefore, there is attained such an effect that the preparation of a thin film covered electrode becomes possible.

Abstract: The surface of an electrically conductive substrate (1) is provided with a redox layer (5) by an electrolytic polymerization process, and the surface of the resulting member is further provided with an ion carrier membrane (6) which includes polyvinyl chloride, a plasticizer and an ion carrier, thereby forming an ion sensor. Used as the plasticizer is one selected from among phthalate plasticizers, maleate plasticizers, adipate plasticizers, carboxylate plasticizers and polycaprolactone plasticizers, or one selected from among plasticizers comprising modified ethylene - vinyl acetate copolymer. The ion sensor obtained has low solubility in the plasticizer of the redox layer and therefore is highly stable. Since the ion sensor has little toxicity, it can be used in vivo. A preferred plasticizer is benzopohenon-tetracarboxylic under cyclic acid.

Abstract: PCT Filed Nov. 19, 1987 PCT Pub. No. WO88/04050 PCT Pub. Date Jun. 2, 1988.An insulative substrate (1) is coated with an electrically conductive layer (2) and a redox layer (3) which comprises an electrolytic polymerization film of 2,6-dimethylphenol, and the surface of the redox layer is provided with an enzyme-fixed (7). The enzyme electrode thus obtained exhibits a potentiometric response, and the enzyme-fixed layer has a strong adhesion. As a result, sensitivity is high, there is little drift and service life is prolonged. An ion-selective field-effect transistor can be used instead of the insulative substrate (1).

Abstract: Disclosed is an enzyme sensor for measuring a predetermined substrate concentration by potentiometric or amperometric response on the basis of an enzyme. In one aspect, a solid-state enzyme sensor measures a predetermined substrate concentration by potentiometric response and includes a solid enzyme membrane-coated electrically conductive base, redox layer or ion-sensitive layer. In another aspect, a solid-state enzyme sensor measures a predetermined substrate concentration by amperometric response and includes a solid enzyme membrane-coated oxygen reduction catalyst layer. Also disclosed is an enzyme control layer for controlling the outflow and inflow of the enzyme layer.