Abstract: An SOx gas sensor includes a first solid electrolyte member composing a part of a wall of a gas reduction chamber and provided with a first gas introducing hole for introducing sample gas into the gas reduction chamber, an oxidation part for oxidizing noise gas other than the SOx gas in the sample gas, and a reduction mechanism for reducing the SOx gas in the sample gas, in the gas reduction chamber; a communication unit provided with a second gas introducing hole for introducing the sample gas into a gas measurement chamber from the gas reduction chamber; and a second solid electrolyte member composing a part of a wall of the gas measurement chamber and provided with an oxidation mechanism for oxidizing the SOx gas, and a measurement mechanism for measuring the concentration of the SOx gas, in the gas measurement chamber.

Abstract: There is provided a sample preparation device and method for preparing a sample of liquid for detection of impurities. First (40) and second (38) electrodes are provided, located for immersion in a liquid under test. A semipermeable membrane (42) is positioned to protect the first electrode (40) from a body of liquid under test (32). The semipermeable membrane allows the liquid under test to pass therethrough to reach the first electrode, while preventing solids carried in the liquid from reaching the first electrode, the first electrode being positioned to affect the liquid under test in the vicinity of a sensor (36). Particular embodiments feature a hydrophilic membrane to protect the electrodes from suspended solids in the sample, a thin electrode assembly to achieve a faster response and the addition of a heater for temperature control to achieve consistent detection conditions and improved anti-fouling properties.

Abstract: A low-slope pH electrode (100) is provided according to an embodiment of the invention. The low-slope pH electrode (100) includes an electrode body (102), a pH-sensitive glass (122) fused into the electrode body (102), with the pH-sensitive glass (122) including a predetermined area, and a mask (124) formed over a predetermined portion of the predetermined area of the pH-sensitive glass (122) in order to form a low-slope pH characteristic. At least a portion of an ion exchange performed by the pH-sensitive glass (122) is blocked by the mask (124).

Abstract: A sensor device for detecting and/or measuring gases includes two electrodes. A thin-layered proton-conductive material is fitted between the two electrodes. The gas can be detected and/or measured by a proton gradient that arises due to different gas concentrations.

Abstract: A combination electrode for ion concentration measurement is provided including a glass electrode and a reference electrode whose internal electrode is made of silver-silver chloride, wherein a sealing means is provided configured to seal an upper surface of a reference electrode chamber formed in an outer tube which houses an internal electrode and an internal solution of the reference electrode, and around a glass support tube penetrating the outer tube along a substantially center axis thereof an annular silver member which the glass support tube penetrates along a center axis thereof, annular sealing elastic members for liquid-tightly sealing a space between the silver member and the glass support tube, and a space between the silver member and the outer tube, respectively, and the reference electrode internal electrode is connected to a terminal for a reference electrode through the silver member.

Abstract: Method and apparatus to measure electrolytes. The apparatus has a measuring portion for measuring electromotive forces generated by a reference fluid and the sample fluid, respectively, by the use of an electrode portion. A dilution vessel for preparing the sample solution by diluting a sample fluid with a diluting fluid. A control portion for providing control such that the reference fluid and the sample solution are alternately supplied to the electrode portion from the dilution vessel and that a given amount of the diluting fluid is supplied to and wasted from the dilution vessel prior to the preparation of the sample solution.

Abstract: Internally calibrated pH and other analyte sensors based on redox agents provide more accurate results when the redox active reference agent is in a constant chemical environment, yet separated from the solution being analyzed in such a way as to maintain electrical contact with the sample. Room temperature ionic liquids (RTIL) can be used to achieve these results when used as a salt bridge between the reference material and the sample being analyzed. The RTIL provides the constant chemical environment and ionic strength for the redox active material (RAM) and provides an electrolytic layer that limits or eliminates direct chemical interaction with the sample. A broad range of RAMs can be employed in a variety of configurations in such “Analyte Insensitive Electrode” devices.

Abstract: A liquid analyzer may include a reference electrode provided with internal liquid containing a halide ion; and an ion electrode of which a measurable concentration range for a measuring target ion is lower than the concentration of the halide ion in the internal liquid of the reference electrode, The internal liquid of the ion electrode contains the measuring target ion and a halide ion; and the internal liquid of the ion electrode is liquid in which the concentration of the measuring target ion and the halide ion are regulated such that an osmotic pressure and an isothermal point of the internal liquid of the ion electrode respectively have desired values, and the isothermal point is included in the measurable concentration range, and the concentration of the halide ion is different from the concentration of the halide ion in the internal liquid S33 of the reference electrode.

Abstract: The electrode assembly is provided with: a rod-like body 1 that extends along a predetermined axis; a substrate that is formed with a through-hole penetrating between a front surface and a back surface and attached to a fore end part of the body; and a sensor chip for electrochemical measurement, which is attached on the back surface of the substrate such that a sensing part is exposed outside from the through-hole, wherein: on the back surface of the substrate, a wiring for obtaining an output signal from the ISFET chip is formed, and the sensor chip is attached to the wiring directly or closely; and the substrate is attached with being inclined with respect to the predetermined axis of the body, and thereby the front surface of the substrate forms at least a part of a fore end surface that is inclined with respect to the predetermined axis.

Abstract: A system for measuring a solution pH includes a potentiostat with a working electrode made of an electro-conductive solid polymer transducer, an input to receive the potential to be applied between the working electrode and a reference electrode, and an output to transmit a signal representative of the current flowing between a counter electrode and the working electrode, the three electrodes being immerged into the solution. The system further includes a digital processor connected to a digital to analog converter for generating the potential to be applied between the working and the reference electrodes; and to an analog to digital converter for receiving a digital value representative of the current. The digital processor is adapted to modify the potential to maintain the current inside a predetermined range such that the potential is representative of the solution pH when the current is inside the predetermined range.

Abstract: Electrolyte analyzers are used in a variety of ways, and problems vary from reagent deterioration due to reagent replenishment, mixing of foreign substances during reagent replenishment, electrode deterioration due to the passage of the validity date, to the operator's inputting errors. It is thus necessary to judge abnormalities of measured values resulting from such inappropriate usage, based on the fluctuation patterns of the results of daily electrolyte calibration. The fluctuation patterns of each measured item are extracted from the results of daily electrolyte calibration. The electromotive force balance ratio between the internal standard solution and high/low-concentration standard solutions is calculated as well as its fluctuation pattern. The obtained fluctuation patterns are compared against atypical fluctuation patterns stored in the electrolyte analyzer. When any of the extracted patterns matches any of the atypical patterns, the analyzer activates an alarm.

Abstract: An electrochemical sensor device including a sensor chip having an integrated electrochemical sensor element; and a substrate having a first surface on which the sensor chip is mounted, the substrate comprising a reference electrode structure for the integrated electrochemical sensor element, the reference electrode structure connected to the sensor chip via an electrical connection on the first surface of the substrate.

Abstract: A low maintenance reference electrode has a liquid junction body with a multiplicity of micron-sized capillary channels extending through the body for transporting electrolyte to a test solution. A viscosity-increasing agent thickens the electrolyte to limit its flow to a rate on the order of microliters/day so that a few milliliters of electrolyte suffice to provide an extended electrode life.

Abstract: Systems and methods are provided for a deep sea pH sensor. In one embodiment, a method for manufacturing a pH sensor comprises forming a sensor electrode in a working surface of a die wherein the sensor electrode is able to sense the pH of a liquid and forming at least one isolation groove around the sensor electrode on the working surface of the die, wherein the die has a wide street around the sensor electrode and the at least one isolation groove. The method further comprises mounting the die onto a base and securing a seal on the working surface in the wide street, wherein the seal surrounds the isolation groove, the seal sealing the liquid within the portion of the working surface of the die containing the sensor electrode and the isolation groove, when the pH sensor is subjected to high pressure.

Abstract: Disclosed are a pH or concentration measuring device and a pH or concentration measuring method which enable measurement in the shortest possible time even in an object to be measured having low buffer capacity.

Abstract: Methods and devices for point of care determination of heparin concentration in blood are described. Cartridges including protamine ion sensitive electrodes (ISEs) and reference electrodes and systems for automatically determining heparin concentration in the cartridges are provided. Some systems add blood to a protamine bolus sufficient to bind all heparin, leaving excess protamine. The excess protamine concentration can be determined by measuring the initial slope of the electrode potential rate of change, and comparing the slope to known protamine concentration slope values In some cartridges, an oscillating pressure source moves the blood-protamine mixture back and forth across the protamine ISE. Some systems also use a second blood sample having the heparin removed or degraded to create a blank reference sample. Protamine ISEs can include polyurethane polymer, DNNS ionophore, and NPOE plasticizer.

Abstract: Microelectrode comprising a body formed from electrically non-conducting material and including at least one region of electrically conducting material and at least one passage extending through the body of non-conducting material and the region of conducting material, the electrically conducting region presenting an area of electrically conducting material to a fluid flowing through the passage in use. An electrochemical cell which includes such a microelectrode is also disclosed.

Abstract: There is provided a sensor head which includes a mounting surface having insulation property. A first electrode and a second electrode are arranged on the mounting surface in a spaced-apart manner from each other. A liquid retaining material is arranged on the mounting surface in a state where the liquid retaining material covers the first electrode and the second electrode integrally. The liquid retaining material is impregnated with a standard liquid which is used as a reference in the electrochemical measurement.

Abstract: An ion sensor includes a sensor main body having a channel for a sample and an opening connected to the channel, a responsive portion which is filled in the opening and selectively responds to a specific ion, an electrode which has a ring shape, is set such that a central axis of the ring is substantially perpendicular to a central axis of the channel, and senses the response, and an output terminal which is formed out of one metal plate out of which the electrode is formed, has a pin shape, and is held by the sensor main body such that an axis extends along a direction substantially perpendicular to the central axis of the channel and the central axis of the ring.

Abstract: An electrochemical sensor and a method for using an electrochemical sensor are described where the electrochemical sensor comprises a working electrode having thereon one or more redox species that are sensitive to an analyte to be measured and a polymer coating that provides for interaction between the redox species and the analyte.

Abstract: Systems and methods are provided for detecting the presence of an analyte in a sample. A solid state electrochemical sensor can include a redox active moiety having an oxidation and/or reduction potential that is sensitive to the presence of an analyte immobilized over a surface of a working electrode. A redox active moiety having an oxidation and/or reduction potential that is insensitive to the presence of the analyte can be used for reference. Voltammetric measurements made using such systems can accurately determine the presence and/or concentration of the analyte in the sample. The solid state electrochemical sensor can be robust and not require calibration or re-calibration.

Abstract: In the present invention, the solid contacted ISE and the solid contacted reference are based on a conductive porous network with a solid contact and membrane disposed thereon. The porous networks are not only mechanically stable, but also provide pore structure for the solid contact and membrane to intercalate, which enhances the life time and stability of the sensors. The invention further incorporates a unique fluidic fitting sensor and sealing mechanism so that measurements can be taken at high pressures. The fitting design has many benefits, such as low cost and disposability, which allows them to be mass manufactured. These sensors can be produced for detection of many different kinds of ions by applying different types of ion selective membranes, including polyvinylchloride (PVC) based ion-selective membranes and fluorous matrixes based ion-selective membranes.

Abstract: An ion-selective potentiometric measuring chain having the I3?/I? redox system as the reference electrolyte is described, in which the components of the reference electrolyte that determine the potential are regenerable. In particular, iodine or I3?/I? solution can be released in a controlled manner from a body situated in the reference electrolyte.

Abstract: An apparatus for real-time, in-situ monitoring of actinide ion concentrations which comprises a working electrode, a reference electrode, a container, a working electrolyte, a separator, a reference electrolyte, and a voltmeter. The container holds the working electrolyte. The voltmeter is electrically connected to the working electrode and the reference electrode and measures the voltage between those electrodes. The working electrode contacts the working electrolyte. The working electrolyte comprises an actinide ion of interest. The reference electrode contacts the reference electrolyte. The reference electrolyte is separated from the working electrolyte by the separator. The separator contacts both the working electrolyte and the reference electrolyte. The separator is ionically conductive to the actinide ion of interest. The reference electrolyte comprises a known concentration of the actinide ion of interest. The separator comprises a beta double prime alumina exchanged with the actinide ion of interest.

Abstract: The NH3 plasma treatment by remote plasma is firstly proposed to replace the covalent bonding process during surface modification procedure that for amine bond generation.

Abstract: The disclosure provides monolithic electrodes including a substrate defining a walled cavity having a floor, an electrically conductive cathode layer overlaying the cavity floor, an electrically conductive contact pad overlaying the substrate, an electrically conductive via in electrical communication with the cathode layer and the contact pad, and a porous membrane layer overlaying the cavity and defining a chamber formed by the porous membrane layer, the walled cavity, and the cavity floor. The disclosure also provides pH transducers including monolithic indicator and reference electrodes, and methods of making and using monolithic pH electrodes and transducers.

Abstract: A sensor device according to an embodiment includes a semiconductor substrate including a plurality of channels, the channels connecting a cavity and a measurement electrode, and a counter electrode arranged to be in contact with the cavity, wherein the cavity, the measurement electrode and the counter electrode are arranged to accommodate a drop of a liquid and to allow a voltage to be applied to the drop of liquid.

Abstract: The present invention relates to the synthesis of lipophilic or immobilized monobasic phosphate (H2PO4) ionophores (7, 8a, 8b and 11) to be used as ion recognition molecules for monobasic phosphate (H2PO4?) in the cocktail preparation of hydrophobic polymer membranes in ion selective electrode (ISE) or ion-sensitive field effect transistor (ISFET) chemical sensors for detection of monobasic phosphate (H2PO4) ionic species in soil, synthetic media, hydrophonic liquid, tree sap, ground water and rivers.

Abstract: In order to realize an accurate electrochemical measurement without a peak caused due to a silver chloride complex ion, an electrochemical measurement electrode of the present invention which measures an electrochemical active substance in a sample solution containing a chloride ion includes (i) a working electrode, (ii) a reference electrode made of silver and silver chloride, and (iii) a silver ion capturing material which captures a silver ion out of a silver chloride complex ion generated in the reference electrode.

Abstract: A method of observing reaction intermediaries during a chemical reaction and comprising detecting an electrical signal output from an ion sensitive field effect transistor exposed to said reaction, and monitoring the detected electrical signal to discriminate discrete fluctuations in the electrical signal, the discrete fluctuations indicating reaction intermediaries occurring during a chemical reaction.

Abstract: The present invention provides an apparatus and method for measuring carbon (any one or all of TC, TOC, or TIC) in a sample matrix. In an embodiment, a method for measuring carbon in a sample composition is provided. The method comprises providing an apparatus comprising a reaction chamber and a diamond coated electrode, wherein the diamond coated electrode is doped with boron. The apparatus further comprises a detector. In addition, the method comprises contacting the sample composition with the electrode. The method further comprises applying an alternating current to the electrode at a sufficient voltage to produce carbon dioxide. Moreover, the method comprises measuring the amount of carbon dioxide produced.

Abstract: A wet flow-type ion selective electrode device requires not only a large amount of test solution but also cumbersome management works such as flow path cleaning and device conditioning. Provided is an ion selective electrode cartridge which includes at least one ion selective electrode forming an electrical path with a reference electrode when a test solution is infused, and in which the ion selective electrode and the reference electrode is arranged to surround a container.

Abstract: The invention relates to an electrochemical sensor including a housing with a chamber containing an electrolyte, at least one measuring electrode for oxygen detection, at least one counter electrode and at least one reference electrode, wherein the sensor has a two-part diffusion barrier, wherein a first part of the barrier forms a labyrinth with a second part of the barrier disposed between the measuring and the counter electrode.

Abstract: A wet flow-type ion selective electrode device requires not only a large amount of test solution but also cumbersome management works such as flow path cleaning and device conditioning. Provided is an ion selective electrode cartridge which includes at least one ion selective electrode forming an electrical path with a reference electrode when a test solution is infused, and in which the ion selective electrode and the reference electrode is arranged to surround a container.

Abstract: An electrochemical sensor includes a polymeric housing and at least a first electrode within the housing. The first electrode includes an electrochemically active surface. The electrochemical sensor further includes a first connector in electrically conductive connection with the first electrode. The first connector includes a first extending member formed from a conductive loaded polymeric material. The first extending member is formed such that an interior thereof comprises conductive elements within a matrix of the polymeric material so that the interior is electrically conductive and an exterior surface thereof comprises the polymeric material and is less conductive than the conductive interior. The conductive interior of the first extending member is in electrically conductive connection with the first electrode. The first connector further includes a first extending conductive element in electrical connection with the conductive interior.

Abstract: A sensing probe intended to measure the content of an oxygen reducible substance in a fluid, includes: a probe body containing an interface and processing circuit, a dry sensing head including an amperometric sensor intended to measure the content of the oxygen reducible substance. The sensing head is removable. The sensing head and the probe body include respectively coupling elements cooperating with each other and able to be separated, and the sensing probe furthermore includes connecting elements designed to connect the removable sensing head to the interface and processing circuit of the probe body.

Abstract: Provided is an ion sensor with which the concentration of ions in a solution can be determined without any reference electrode. The ion sensor is equipped with: a first electrode plate; a second electrode plate which has been disposed opposite the first electrode plate and has one or multiple openings; an ion-sensitive film continuously formed so that the film is interposed between the first electrode plate and the second electrode plate, blocks up one side of each opening of the second electrode plate, and extends from the end of that side of the opening to the outer surface of the second electrode plate through the inner wall surface of the opening; and a sensor support which supports the second electrode plate so that when the ion concentration of a test solution to be examined is determined, the ion-sensitive film comes into contact with the test solution only in the portions thereof that have been formed in each opening and on the outer surface of the second electrode plate.

Abstract: A multiple-electrode ion meter (100) is provided. The multiple-electrode ion meter (100) includes meter electronics (102) configured to receive a plurality of ionic concentration voltage measurements and generate an ionic concentration measurement from the plurality of ionic concentration voltage measurements and three or more individual electrode units (108) in communication with the meter electronics (102). The three or more electrode units (108) generate the plurality of ionic concentration voltage measurements to the meter electronics (102).

Abstract: A handheld sensor device is provided for measuring an ion concentration in a solution. The solution is in an electrochemical cell that includes a counter electrode, a working electrode, and a reference electrode. The sensor includes a control amplifier configured to provide a current through the counter electrode and the working electrode so as to maintain a predetermined voltage between the working electrode and the reference electrode. The sensor also includes a current amplifier configured to measure the current provided through the counter electrode and the working electrode. In one embodiment, the sensor also includes a direct digital frequency synthesizer (DDFS) including a phase accumulator. The DDFS is configured to selectively generate a waveform specified by an electrochemical technique such as square wave voltammetry, cyclic voltammetry, linear sweep voltammetry, differential-pulse polarography, normal-pulse polarography, or other known electrochemical techniques.

Abstract: The invention relates to a pH measuring device containing a reference cell which includes a tank filled with an electrolyte solution and a platinized platinum reference electrode immersed in the tank. The measuring device also contains a measuring cell. The measuring cell contains a platinized platinum measuring electrode which is immersed in the solution to be measured. The measuring device also contains a temperature regulator to ensure that the temperature is the same in the reference cell as in the measuring cell. The measuring device also contains a particle pressure regulator to ensure that the hydrogen partial pressure is the same in the reference cell as in the measuring cell and a fluid pressure regulator to ensure that the pressure is the same in the reference cell as in the measuring cell.

Abstract: A system for monitoring the viability of an electrochemical cell measures the impedance of the cell over a wide range of impedances and with diminished phase shift over prior methods so that a more nearly accurate assessment of the impedance can be made. The system is particularly useful for four electrode systems, but is not so limited. It may advantageously be incorporated in the cell itself to further minimize cabling artifacts.

Abstract: An apparatus and method for electrochemical fluid analysis comprises a chamber (1202) having a depth dimension for accommodating a volume of a fluid under test, first and second electrodes (A1) disposed within the chamber and extending along the depth dimension in spaced relation with each other, and a soluble solid, such as an annealed polymer, e.g. EUDRAGIT occupying a lateral gap between the first and second electrodes. The rate of dissolution as monitored by electrochemical impedance spectroscopy (EIS) of the soluble solid within the fluid depends on the chemical concentration of a corresponding analyte present in solution in the fluid. In one embodiment a silicon-based integrated circuit device defining an upper margin includes an array of electrodes disposed along said upper margin to permit direct exposure of the electrode array to the fluid under test. The device is constructed using CMOS technology.

Abstract: Improvements in references electrodes, halogen sensors, pH sensors, TDS sensors, combinations thereof, and related methods.

Abstract: A pH sensor is provided. The pH sensor comprises a substrate and an ion sensitive field effect transistor (ISFET) die comprising an ion sensing part that responds to pH, wherein the ISFET die is located over the substrate. The pH sensor also comprises a protective layer formed over at least a portion of an outer surface of the ISFET die and at least a portion of the substrate. Further, the pH sensor comprises a cover member mechanically coupled to the protective layer, wherein the cover member houses the ISFET die and the substrate, and wherein the cover member defines an opening proximate to the ion sensing part.

Abstract: Micromachined reference electrodes for use in miniaturized electrochemical sensors, and methods for fabricating such reference electrodes and electrochemical sensors, for example, as a part of a microfluidic system, are disclosed. Electrochemical measurements allow for inexpensive detection of a wide variety of (bio-)chemical compounds in solution. The reference electrode is one of the main parts of an electrochemical cell. The reference electrode, from which no current is drawn, has a stable, constant potential.

Abstract: Described herein are substrates, sensors and systems related to measuring the concentration of an analyte such as hydrogen ion in a sample. Redox active moieties whose reduction and/or oxidation potentials are sensitive to the presence of an analyte are immobilized onto a surface of an electrode. Immobilized redox active moieties whose reduction and/or oxidation potential are insensitive to the analyte can be used for reference. Voltammetric measurements made using such modified surfaces can accurately determine the presence and/or concentrations of analytes in a sample of interest. The electrochemical sensors of the invention are robust and can be made so as not to require calibration or recalibration.

Abstract: Ion-selective electrodes (ISE's) optimised for analyte determinations and provides methods and apparatus for conditioning ion selective electrodes. The conditioning methods and apparatus are particularly useful for ISE's selective for, difficult to condition, less stable and temperature sensitive products, an are based on a concentration gradient and/or a short exposure to an increased temperature.

Abstract: An electrochemical gas sensor with a plurality of electrodes is provided with an electrolyte, with a gas-permeable membrane (1), with a gas-permeable and conductive carrier layer (2) applied to the membrane (1) and with at least one measuring electrode (3) applied to the carrier layer (2). The measuring electrode (3) is of a punctiform design and the electrochemical potential difference of the reaction between the carrier layer (2) and the measuring electrode (3) is at least 20 mV, can be manufactured in a compact form and makes possible an especially low power consumption for measured gases in the percentage range.

Abstract: Methods are disclosed for reducing the shift in EMF bias in a magnesium ion selective electrode, comprising the step of: contacting the electrode with a composition comprising a polyoxyalkylene nonionic surfactant; wherein the polyoxyalkylene nonionic surfactant has an HLB greater than about 18. Additional aspects of the present invention are directed to methods, comprising the steps of: contacting a magnesium ion selective electrode with a composition comprising a polyoxyalkylene nonionic surfactant, wherein the polyoxyalkylene nonionic surfactant has an HLB greater than about 18; and measuring a biologically relevant level of a blood electrolyte in a blood composition with the electrode. In certain embodiments, the polyoxyalkylene nonionic surfactant is polyoxy ethylene (100) stearyl ether and the blood electrolyte is magnesium ion.

Abstract: An electrochemical test sensor adapted to assist in determining the concentration of analyte in a fluid sample is disclosed. The sensor comprises a base that assists in forming an opening for introducing the fluid sample, a working electrode being coupled to the base, and a counter electrode being coupled to the base, the counter electrode and the working electrode being adapted to be in electrical communication with a detector of electrical current, and a sub-element being coupled to the base. A major portion of the counter electrode is located downstream relative to the opening and at least a portion of the working electrode. The sub-element is located upstream relative to the working electrode such that when electrical communication occurs between only the sub-element and the working electrode there is insufficient flow of electrical current through the detector to determine the concentration of the analyte in the fluid sample.