Abstract: A highly accurate, long life, low cost gas sensor is disclosed, particularly useful for measuring carbon monoxide and other toxic gases in an environment. The gas sensor has a first, sensing electrode and a second, counting electrode. Positioned between the first and second electrodes is an ion conducting, solid electrolyte membrane. In response to the presence of a toxic gas introduced to the first electrode, an electric signal is produced between the first electrode and the second electrode. The electric signal changes in response to changes in the concentration of the toxic gas. Detection circuitry measures the electric signal to determine the concentration of the toxic gas. An electrically conductive, hydrophobic top membrane electrically connects the first electrode to the detection circuitry while preventing liquid water from contacting the first electrode. An electrically conductive, hydrophobic bottom membrane electrically connects the second electrode to the detection circuitry.

Abstract: A detection chip capable of detecting large amounts of genes with high sensitivity is provided. The gene detection chip comprises a plurality of pins 12 as measurement electrodes, a common electrode 22 as a counter electrode therefor, and a tabular member 14 with a plurality of pin holes 15 for accommodating the pins. An arrangement may be adopted in which the diameters of the pin holes 15 taper off in the direction in which the pins are inserted, and the pins are held in place in the narrowest sections of the pin holes 15.

Abstract: In a method of measuring the concentration of a substance such as glucose in a sample liquid such as blood or interstitial fluid, a measuring device is provided having a working sensor part (6b), a second working sensor part (8b) and a reference sensor part (4b). The sample liquid is applied to the measuring device and an electric current proportional to the concentration of the substance in the sample liquid is measured at each sensor part (6b, 8b). The electric currents are compared to establish the difference. If the difference is greater than a predetermined threshold, an error indication is given. A disposable test strip with two working sensors (6b, 8b) is also disclosed.

Abstract: As embodied and broadly described herein, the invention provides an electrode test strip. The electrochemical electrode test strip comprises an insulating base plate, a electrode system on the base plate, a spacer which partially covers the electrode system and a channel trench with a constant width is formed thereof, a reactive film, and a cover on the spacer with an first opening thereof. Wherein the electrode system comprises at least a working electrode and a reference electrode, and the working electrode and the reference electrode is isolated. The reactive film contains at least on active species that can have a specific redox reaction with the analyte. The first opening exposes the channel trench, and two second openings are located at the two ends of the channel trench.

Abstract: A method for detection of a bubble in a liquid which is placed in a measuring chamber and is in contact with a sensor for measuring the partial pressure of a particular gas in a liquid is provided. The method includes performing a first measurement of the partial pressure of the particular gas in the liquid at a first pressure in the measuring chamber. Next, the pressure in the measuring chamber is changed to a second pressure. A second measurement of the partial pressure of the gas in the liquid at the second pressure in the measuring chamber is performed. An expected result of the second measurement based on the first measurement and assuming that no bubbles are present in the measuring chamber during any of the measurements is provided. The actual result of the second measurement is compared with the expected result and a conclusion is drawn on the presence of a gas bubble in the liquid based on the comparison. An apparatus for measuring the content of a particular gas in a liquid is also provided.

Abstract: A reference electrode assembly having a constrained-diffusion liquid junction between a liquid junction solution and a sample solution having separate flow paths, said assembly comprising a flow cell having attached thereto a constraint comprising a region of porous material permeable to water and salts; a remote reservoir for holding said liquid junction solution; a means for moving said liquid junction solution from said reservoir to said constraint; and a reference contact region is provided. This unique configuration provides a reference electrode device of the constrained-diffusion liquid junction type useful in pH and/or ion-selective electrode (ISE) potentiometric sensors and is particularly suitable for use in a mini-integrated electrochemical analyzer.

Abstract: A measuring arrangement for the analysis of gas components in gas mixtures, having at least one electrochemical solid electrolyte test cell with at least one cathode in a diffusion channel is exposed to a gas mixture. The use of several cathodes wired one behind the other makes possible selective analysis of individual gas components. At the first cathode, oxygen is selectively pumped off by the use of specifically oxygen-ion-conductive layers so that another component of the gas mixture can be analyzed by the following electrode.

Abstract: A sensor for determining the concentration of sulphur compounds in a liquid includes: a working electrode in contact with the liquid to be analyzed; a referenced electrode insulated from the liquid to be analyzed; a liquid-impermeable membrane located between the working electrode and the reference electrode and permeable to an ion that may form a chemical compound with the sulphur compounds in the liquid to be analyzed; and a reference material in contact with the reference electrode or forms the reference electrode.

Abstract: An electrochemical sensor for determining gas components and/or gas concentrations in gas mixtures using a sensor element is described; it has at least one electrode arranged on an ion-conducting solid electrolyte body bordering on a gas space in at least some areas. The electrode has at least two layers, the second layer which faces the gas space having a higher electron conductivity in comparison with the first layer which faces the solid electrolyte body.

Abstract: A chemical sensor selectively detects an analyte in a solution. The sensor comprises a flow-through chamber, a selective membrane, a transducer, an inlet for a liquid flow containing a recognition element, and an outlet. To detect an analyte in a solution, a recognition element is contacted with the solution containing the analyte via a selective membrane. This results in a response detectable by a transducer. The recognition element is injected into a flow, and the flow is passed into a flow-through chamber comprising the transducer and the selective membrane, where it contacts the analyte passing from the solution outside the chamber. The recognition element and the analyte interact to provide a signal that is detected by the transducer. The chemical sensor is used for detecting analyte(s) in a reactor system, a flow system or in an in vivo system.

Abstract: A biosensor enabling accurate measurement of the concentration of a substrate contained in a trace amount of a sample solution is disclosed. The electrochemical analysis element in accordance with the present invention which should be included in the biosensor comprises a sensor body having a hollow space which space is open at its both ends, an electrode system having a working electrode and a counter electrode, a reagent segment containing an enzyme, wherein the electrode system and the reagent segment are disposed on an inner wall of the hollow space.

Abstract: A measured gas side electrode is provided on one surface of a solid electrolytic substrate so as to be exposed to a measured gas. A reference gas side electrode is provided on an opposite surface of the solid electrolytic substrate so as to be exposed to a reference gas stored in a reference gas chamber. A water-vapor absorbing member is provided in the reference gas chamber.

Abstract: The invention relates to a sensor for detecting substance concentration or activity or for determining the presence of substances based on electrochemical reactions. The electrochemical sensor comprises an electrode with surfaces inside the electrode, wherein electrochemical detection reactions occur. Said sensor guarantees high flow densities and is suitable for miniaturization. A substance-recognizing agent is advantageously placed in the electrode in contact with the inner surfaces. This enables not only short response times and long service life but also measurements with excellent linearity.

Abstract: An electrochemical gas sensor, which has a substantially more compact design and is manufactured with a considerably reduced manufacturing effort. A conical, calotte-shaped, hemispherical or cylindrical outer housing is provided with gas admission openings (3, 203). A cover (8, 208) as well as a layer structure is provided with, from the outside to the inside, the diffusion membrane (4, 204) with the electrodes (5, 6, 7; 205, 206, 207) applied thereto in a planiform manner, a layer (11, 211) consisting of a mat material or a porous body, which accommodates the electrolyte, and an electrolyte space (10, 210), which is filled at least partially with the electrolyte.

Abstract: An electrochemical sensor for detecting the presence and amount of acetate in cell culture and fermentation media. The electrochemical sensor has a pH electrode, an internal reference electrode, a special high-tensile strength gas permeable membrane, and internal reference electrolyte such that acetate concentration can be measured using a pretreatment buffer having a pH of about 5.5.

Abstract: A NOx sensor for measuring NOx concentration including a main pumping cell and a detecting electrode, the main pumping cell-including an electrode having no decomposing/reducing ability for NOx or a low decomposing/reducing ability for NOx, to be used to control oxygen concentration in a measurement gas to have a predetermined value at which NO is not substantially decomposable, and the detecting electrode having a certain decomposing/reducing ability for NOx or a high decomposing/reducing ability for NOx, to be used so that NOx is decomposed to measure the NOx concentration by measuring an amount of oxygen produced during this process, wherein a cermet electrode composed of a Pt—Rh alloy and a ceramic component is used as the detecting electrode. Accordingly, it is possible to suppress the oxidation of Rh and the reconversion into the metal contained in the detecting electrode, stabilize the impedance, and stabilize the sensitivity to NOx.

Abstract: A measuring probe for potentiometric measurements has a housing (2) of an electrically insulating material surrounding an enclosed space (4). Inside the space (4) are a primary reference element (6), a secondary reference element (8), an electrolyte (10), and an ion-permeable, micro-porous, high-viscosity polymer substance which, in combination with the electrolyte (10), forms a filler mass (16). The housing (2) has at least one opening (12) to the outside, through which the electrolyte (10) can be brought into contact with a sample solution on which a measurement is to be performed. The secondary reference element (8) is arranged so that the boundary (52) of an electrolyte-deficient region (54) advancing over time from the opening (12) towards the primary reference element (6) arrives at the secondary reference element (8) before reaching the primary reference element (6).

Abstract: A device for utilizing a non-gel self-assembled nano-feature array molecular sieve for analyzing molecules is provided. The molecular sieve device comprises an ordered array of self-assembled nano-features which function as a molecular sieve to separate molecules based on a suitable characteristic. A system for integrating the non-gel ordered self-assembled nano-feature array molecular sieve of this invention into a device for separating molecules based on a characteristic and a method for separating a wide range of molecules using the non-gel ordered self-assembled nano-feature array molecular sieve of the invention are also provided.

Abstract: An electrochemical gas sensor is provided which can be assembled economically and in a few steps. The electrodes (1, 2, 3) with associated electric lines are applied in a planiform manner to a membrane strip, which is impermeable to the electrolyte but permeable to gases. The membrane strip (6) is deposited in the sensor housing in a zigzag-folded pattern, so that the membrane strip limits the opening of the sensor housing for the entry of the measured gas. The electrodes (1, 2, 3) are arranged stacked in the sensor housing (5, 7) at spaced locations from one another due to the membrane strip (6) deposited in a zigzag-folded pattern.

Abstract: The invention relates to a method and a system, suitable for automation, for the, preferably preparative, separation of amphoteric macromolecules, e.g. proteins or peptides, wherein said method comprises the steps of: (a) subjecting said mixture of macromolecules to isoelectric focusing in liquid media; (b) collecting samples from step (a), said samples containing macromolecules separated on basis of isoelectric point, and transferring each sample to a channel (13) accommodating medium for electrophoresis, said channel (13) being part of a composite body (14); (c) subjecting said samples, contained in the channels (13) in said composite body (14), to electrophoresis; and (d) allowing electrophoresis to proceed until macromolecules are eluted from said medium for electrophoresis, and collecting fractions of the samples containing macromolecules.