Abstract: Histamine may be quantitatively measured by performing the following steps. First, an oocyte that expresses histamine receptors is held in a recess formed at the bottom of a vessel. Then, first and second electrodes are inserted into the oocyte. Subsequently, the membrane potential of the oocyte is measured by using the first electrode to stabilize this membrane potential at a predetermined level by driving a current through the second electrode using circuitry for clamping the membrane potential of the oocyte. A sample is then infused into a fine reacting tube having an antigen immobilized on its inner surface together with some buffer solution to promote a histamine releasing reaction. The solution containing histamines that is released in the fine reacting tube is transferred to the vessel to make contact with the oocyte in the vessel.

Abstract: Disclosed is an improved electrochemical sensor having a base bearing a working and counter electrode which provides a flow path for a fluid test sample. The working electrode has a reaction layer on its surface which contains an enzyme capable of reacting with an analyte to produce electrons which are received by the working electrode. The base is mated with a cover to form a capillary space into which the test fluid is drawn. The improvement involves configuring the working and counter electrodes so that a major portion of the counter electrode is located downstream on the flow path from the working electrode with the exception of a small sub-element of the counter electrode which is in electrical communication with the primary portion of the counter electrode and located upstream of the working electrode.

Abstract: The invention provides a mechanically stable substrate having at least one through-opening, a perforated membrane which is integral or fluid-tightly connected with the substrate and which extends across the through-opening, and at least one semi-permeable layer which is applied in firmly adhering manner to one or both sides of the membrane, at least in the perforated region thereof, in that the semi-permeable layer or semi-permeable layers is/are secured mechanically in the adjacent perforations and/or by chemical-structural and/or physical adhesion and/or adhesive intermediate layers and/or covalent surface bonding to the adjacent surfaces of the membrane, optionally of the substrate, or of a metallic film optionally additionally applied to one or both sides of the membrane. The invention further provides a process for the production of this sensor- and/or separating element and the use thereof.

Abstract: An apparatus for identifying an unknown reactive gas in a carrier gas, utilizing a sensor with a diffusion limited inlet. The apparatus includes a manifold of predetermined volume having an inlet and outlet, an inlet valve in the manifold inlet, an outlet valve in the manifold outlet, a gas detector in communication with the manifold, a diffusion barrier disposed between the manifold and the gas detector for limiting diffusion of gas from the manifold into the gas detector, means for opening and closing the inlet and outlet valves, means for detecting an output signal from the gas detector, means for determining a coefficient of diffusion for the reactive gas from the output signal, and means for identifying and quantifying the reactive gas from the determined coefficient of diffusion.

Abstract: A diagnostic card device for use in detecting or quantitating an analyte present in a liquid sample, comprising a card substrate having a sample introduction region, a biosensor, and a sample-flow pathway communicating between the sample-introduction region and the biosensor, circuitry for generating an analyte-dependent electrical signal from the biosensor; and a signal-responsive element for recording such signal. In one embodiment, the biosensor includes a detection surface with surface-bound molecules of a first charged, coil-forming peptide capable of interacting with a second, oppositely charged coil-forming peptide to form a stable &agr;-helical coiled-coil heterodimer, where the binding of the second peptide to the first peptide, to form such heterodimer, is effective to measurably alter a signal generated by the biosensor. The sample-flow pathway contains diffusibly bound conjugate of the second coil-forming peptide and the analyte (or an analyte analog) and immobilized analyte-binding agent.

Abstract: A sensor utilizing a non-leachable or diffusible redox mediator is described. The sensor includes a sample chamber to hold a sample in electrolytic contact with a working electrode, and in at least some instances, the sensor also contains a non-leachable or a diffusible second electron transfer agent. The sensor and/or the methods used produce a sensor signal in response to the analyte that can be distinguished from a background signal caused by the mediator. The invention can be used to determine the concentration of a biomolecule, such as glucose or lactate, in a biological fluid, such as blood or serum, using techniques such as coulometry, amperometry, and potentiometry. An enzyme capable of catalyzing the electrooxidation or electroreduction of the biomolecule is typically provided as a second electron transfer agent.

Abstract: The invention relates to compositions and methods useful in the electrophoretic transport of target analytes to a detection electrode comprising a self-assembled monolayer (SAM). Detection proceeds through the use of an electron transfer moiety (ETM) that is associated with the target analyte, either directly or indirectly, to allow electronic detection of the ETM.

Abstract: The invention concerns a sampling system and a process for its production. Such systems can easily be employed throughout in chemical and biochemical analysis. The sampling system should be simply constructed and universally usable alone and in combination and fabricable with little effort. The sampling system constructed as per the invention for analytes which are fluid or are contained in fluids consists of a planar support with various holes in it through which the particular fluid can pass into a channel which it subsequently exits. The channel is at least partly covered by a cover over the side opposite the support. In addition, a membrane pervious to the analyte is inserted which at least partly covers the channel on its open upper side. The areas not covered by the cover can be used to extract the analyte or to make direct measurements.

Abstract: Histamine may be quantitatively measured by performing the following steps. First, an oocyte that expresses histamine receptors is held in a recess formed at the bottom of a vessel. Then, first and second electrodes are inserted into the oocyte. Subsequently, the membrane potential of the oocyte is measured by using the first electrode to stabilize this membrane potential at a predetermined level by driving a current through the second electrode using circuitry for clamping the membrane potential of the oocyte. A sample is then infused into a fine reacting tube having an antigen immobilized on its inner surface together with some buffer solution to promote a histamine releasing reaction. The solution containing histamines that is released in the fine reacting tube is transferred to the vessel to make contact with the oocyte in the vessel.

Abstract: Single-channel thin film devices and methods for using the same are provided. The subject devices comprise cis and trans chambers connected by an electrical communication means. At the cis end of the electrical communication means is a horizontal conical aperture sealed with a thin film that includes a single nanopore or channel. The devices further include a means for applying an electric field between the cis and trans chambers. The subject devices find use in applications in which the ionic current through a nanopore or channel is monitored where such applications include the characterization of naturally occurring ion channels, the characterization of polymeric compounds, and the like.

Abstract: Histamine may be quantitatively measured by performing the following steps. First, an oocyte that expresses histamine receptors is held in a recess formed at the bottom of a vessel. Then, first and second electrodes are inserted into the oocyte. Subsequently, the membrane potential of the oocyte is measured by using the first electrode to stabilize this membrane potential at a predetermined level by driving a current through the second electrode using circuitry for clamping the membrane potential of the oocyte. A sample is then infused into a fine reacting tube having an antigen immobilized on its inner surface together with some buffer solution to promote a histamine releasing reaction. The solution containing histamines that is released in the fine reacting tube is transferred to the vessel to make contact with the oocyte in the vessel.

Abstract: The invention relates to compositions and methods useful in the acceleration of binding of target analytes to capture ligands on surfaces. Detection proceeds through the use of an electron transfer moiety (ETM) that is associated with the target analyte, either directly or indirectly, to allow electronic detection of the ETM.

Abstract: The apparatus of the invention includes a flow chamber having an inlet, an outlet, and a removable cover. The cover includes fittings for mounting a reference electrode assembly, a measuring electrode assembly, and a combined counter electrode/thermistor probe. According to the one illustrative embodiment invention, the flow chamber is substantially cylindrical with the inlet located near the bottom of the chamber and the outlet located near the top of the chamber. The axes of the inlet and outlet lie in the same plane as and are parallel to a diameter of the chamber. The inner diameter of the inlet is reduced to approximately ⅛″ so that the velocity of water entering the chamber is increased. The inner diameter of the outlet is approximately ¼″ so that the velocity of water exiting the chamber is less than the velocity of water entering the chamber.

Abstract: A potentiostatic analyzer for active halogens in conducting solutions that contain also the corresponding halide comprises, in combination: a) a concentration-to-current transducer, which is an electrolytic cell; b) means for providing a controlled flow of the solution being analyzed through the cell; and c) a potentiostatic transmitter for controlling the electrodes of the electrolytic cell.

Abstract: A method and apparatus uses a flow injection technique for rapidly and accurately determining the level of one or more additives such as antioxidants and/or antiwear agents in a hydrocarbon fluid such as an engine oil. The hydrocarbon fluid is injected into a mobile phase using a microemulsion or organic solvent as the mobile phase and pumped through an electrochemical detection sensor. The electrochemical detention sensor accurately and quickly provides a sharp signal identifying the electroactive species in the hydrocarbon fluid.

Abstract: A blood analyzer sensor cartridge comprises a housing having chamber and a sensor assembly within the chamber, a first fluid port having an articulated inlet aspiration tube for direct introduction of a sample, a first fluid path in the housing communicating the first fluid port with the sensor assembly, a second fluid port in the housing adapted for connection to an analyzer, and a second fluid path in the housing communicating the sensor assembly with the second fluid port, the articulated tube is pivotally mounted to the housing for selective orientation within a range of up to ninety degrees, the tube is moveable from a protective recess in the housing to a position normal to a face of the housing.

Abstract: A mesoscale sample preparation device capable of providing microvolume test samples, separated into a cell-enriched fraction and a fraction of reduced cell content, for performing various analyses, such as binding assays, determinations involving polynucleotide amplification and the like. Analytical systems including such devices are also disclosed.

Abstract: A method of manufacture of a thin layer electrochemical cell (FIGS. 12, 14) comprising the steps of: forming an aperture (11) extending through a sheet (1) of electrically resistive material, said aperture defining a side wall of the cell, mounting a first thin electrode layer (13) to one side of the sheet and extending over aperture (11) whereby to define a cell first end wall, mounting a second thin electrode layer (13) to the other side of the sheet and extending over aperture (11) whereby to define a second cell end wall in substantial overlying registration with the first electrode, and providing means (16) for admission of a liquid into the cell.

Abstract: A method and apparatus for identifying an unknown reactive gas in a carrier gas, utilizing a sensor with a diffusion limited inlet. After a signal is established for the carrier gas, a flow of the mixture of carrier gas and reactive gas is passed to the sensor and a steady state signal S is established. Then, the input to and output from the sensor are closed, and the steady state signal decays as a known volume of reactive gas is consumed. The decay curve of the signal is integrated to produce an integrated response .SIGMA., and the ratio S/.SIGMA. is proportional to the diffusion coefficient for the reactive gas. By comparing this ratio to the ratio for a known reactive gas, the identity of the unknown reactive gas can be determined.

Abstract: An ion concentration measuring electrode unit includes a body member having a plurality of capillary tubes extending through the body member to provide a plurality of passageways for a sample fluid to be tested. The gaps between the hollow tubes are sealed to maintain an internal solution complimentary to the ion to be measured. An internal electrode is immersed within the internal solution whereby a large internal surface area is provided to enable a reduced impedance in measurement of a sample fluid. An ion concentration meter assembly is thereby provided when combined with a sample flow conduit directing fluid through the body member with a liquid junction connected to the conduit and to a reference electrode unit whereby outputs of the internal electrode and a reference electrode can be used to measure an ion concentration.

Abstract: Materials and methods are provided for producing patterned multi-array, multi-specific surfaces which are electronically excited for use in electrochemiluminescence based tests. Materials and methods are provided for the chemical and/or physical control of conducting domains and reagent deposition for use in flat panel displays and multiply specific testing procedures.

Abstract: An electrochemical sensor electrode strip that measures analyte concentration in an aqueous sample as small as 2.5 to 2.0 .mu.L is described. Reduction in the minimum sample size is achieved by means of a dielectric coating impregnated into peripheral regions of one or more hydrophilic mesh layers, thereby reducing sample dead volume. The mesh layers are located between an electrode support and a cover layer, which cover layer includes an aperture located upstream from an electrode arrangement.

Abstract: Sensor cartridges include a fluid constituent-selective sensor membrane in direct sealing contact with a face of a flow-through sample cell in surrounding relationship to a sensor port. The sensor membrane has sufficiently large surface area so as to entirely cover the sensor port and establish an annular region in surrounding relationship thereto. It is this annular region which is in direct contact with a corresponding region of the sample cell face so as to provide self-sealing capabilities. The sensor cartridge most preferably includes a flow-through sample cell having a zig-zag or serpentine flow channel so as to provide a series of sensor ports on both of the opposed cell faces. The faces of the sample cell are most preferably provided with recessed regions which define a series of land surfaces each of which surrounds a respective one of the sensor ports.

Abstract: The device (1) has a cell (3) with an electrode structure for carrying out electrochemical detection or measurement of a liquid sample. A means for mechanically or pneumatically drawing the liquid sample into the cavity (20) of the cell (3) is provided. The drawing means may be in the form of a strip (10) which is mechanically drawn through the cell (3) drawing the liquid sample into the cavity (20) of the cell (3). The strip (10) can have a V-shape (44) portion which is placed in the liquid sample before the strip (10) is drawn through the cell (3).

Abstract: A flow cell for use in an analytical system of the type that may be used to test water samples for specific analytes. The flow cell reduces or eliminates the effects of backpressure on a liquid stream passing through the flow cell. This allows a sensor to be incorporated with the flow cell and enables the sensor to provide consistent output with respect to the analyte being tested without introducing signal error due to backpressure fluctuations.

Abstract: A filter has a first filter layer made of TiO.sub.2 of Ti.sub.4 O.sub.7 particles deposited on a second filter layer by stainless steel particles. The first layer has a smaller pore size than the second layer. The construction of the filter, the relative thicknesses of the layers and the resistances thereof to movement therethrough of electrolytically generated gas located between the two layers when the filter is permeated with liquid are such that the gas reaches the upstream side of the filter before the downstream side. In one embodiment stainless steel particles are sintered and rolled with a textured roller before ceramic particles are applied and rolled. An intermediate layer of metal particle peaks and ceramic filled troughs is thus provided which has high tortuosity. The resistance to flow at the metal/ceramic interface can be increased by electrodeposition of metal there.

Abstract: The present disclosure relates to an on-line lactate sensor arrangement. The sensor arrangement includes a lactate sensor, a catheter for withdrawing a test sample, and a first fluid flow line provided fluid communication between the lactate sensor and the catheter. The sensor arrangement also includes a source of sensor calibration and anticoagulant solution, and second fluid flow line providing fluid communication between the source of sensor calibration and anticoagulant solution and the lactate sensor.

Abstract: A device for testing body fluids is disclosed, the device comprising an electrode body having an enclosed flow chamber extending longitudinally therethrough. A valve assembly is in liquid communication with the flow chamber and also detachably mounts a syringe thereon. The valve assembly provides liquid communication between a syringe mounted thereon and the flow chamber. A plurality of electrode cells is detachably mounted to the electrode body and is in liquid communication with the flow chamber. The plurality of electrode cells measures electrical resistivity, rH.sub.2, and pH. A circuit electrically connects the plurality of electrodes to an interface providing data output and command input.

Abstract: Methods for determining the amount of volatile electrolyte present in an aqueous liquid sample comprise transferring the electrolyte from the aqueous liquid sample to an absorber solution across a gas-permeable membrane which is non-passable to the aqueous liquid sample and measuring the change in electrical conductivity of the absorber solution during the transfer period. The absorber solution contains a solute which enhances the transfer of the electrolyte. Apparatus for conducting such methods include an absorber solution containing a solute which enhances the transfer of the electrolyte.

Abstract: An electrode assembly (1) for resistive pulse spectroscopy comprises two flat electrodes (3) substantially equal in size and shape and supported in face-to-face, parallel relationship to one another, and a plate-like fluid-tight insulator (2) positioned between electrodes and extended beyond the periphery of the electrodes with the electrodes (3) being fixed to the insulator (2). Each electrode has a hole (4) extending through the electrode in a central region thereof (4), the holes (4) of the two electrodes (3) being aligned with one another. The insulator (2) having a preformed aperture (16) therein which is located substantially centrally with respect to the holes (4) in the electrodes (3) and has a smaller diameter than the holes, the aperture (16) being located such as to allow a flow of liquid to pass therethrough and through the holes in the electrode.

Abstract: A conductivity sensor for measuring hematocrit and a sensor housing for a blood analysis instrument using the conductivity sensor are described. The conductivity sensor includes a seven-electrode conductivity measurement cell in which three symmetric pairs of electrodes are arranged on opposite sides of a central electrode. The central electrode is connected to an AC source and the outermost pair of electrodes, which provide a return path for the current, are maintained at a ground or reference potential. The two inner pairs of electrodes measure the voltage drop along the current flow path. This arrangement confines the measurement current and potential within the sensor chamber, thereby preventing the sensor from interfering with other electrochemical sensors that may be provided in the blood analysis instrument. The sensor housing provides a linear arrangement of flow cells defining a fluid flow path through the housing.

Abstract: The present invention provides novel microfluidic devices and methods that are useful for performing high-throughput screening assays. In particular, the devices and methods of the invention are useful in screening large numbers of different compounds for their effects on a variety of chemical, and preferably, biochemical systems.

Abstract: The electroanalytical, voltammetric cell includes a cell body housing, in addition to a reference electrode, a working electrode and, in its lowermost portion, a counter-electrode. An arrangement for deoxygenating the sample solution includes feeding the sample solution through a deoxygenation conduit in contact with a stream of an inert gas. An inlet for the deoxygenated sample solution is provided in the cell body in the space between the working electrode and the counter-electrode, and an exit for the sample solution is provided in the cell body at a level above the working electrode. Vacuum and/or pressure is utilized for causing the sample solution to flow to the exit, to be discharged from the cell above the working electrode, thus assuring that the space between the working electrode and the counter-electrode is constantly filled with sample solution.

Abstract: The present invention relates to a method for defining an area (4) of a layer on a porous substrate comprising compressing a volume of the substrate to produce a compressed region (8) which defines, or which in combination with an edge (7) of the substrate or of the layer defines, a boundary of the area and which substantially prevents the transport of material through or across its surface. The present invention also relates to an electrochemical sensing device comprising: a porous substrate; and an electrode (1) on one side of the substrate; wherein a region of the substrate is compressed to an extent which forms a barrier to migration of electrolyte within the substrate, the compressedregion defining, or in combination with an edge of the substrate or the electrode defining, a zone on the electrode of predetermined area.

Abstract: A method and apparatus for determining the quantity of a substance in a solution. An exemplary embodiment of the method includes the step of introducing a first sample of the solution into a cavity in which a working electrode is located. A constant potential is applied between the working electrode and a reference electrode in electrical contact with the first sample until such time as the current through the working electrode has decayed to a minimum. The applied constant potential is maintained as the first sample of the solution is replaced by a second sample of the solution in a manner such that the cavity remains filled with solution during the replacement procedure. The applied constant potential is maintained until such time as the current through the working electrode has again decayed to a minimum, and the total amount of the charge passing through the working electrode subsequent to the introduction of the second sample into the cavity is determined.

Abstract: A graded metal hardware component for an electrochemical cell is shown for mechanically supporting electrochemical cell structures and defining fluid cavities and fluid passages in a cell employing a solid polymer electrolyte membrane. The graded metal hardware component includes a substrate such as stainless steel, a surface layer made of a precious metal such as gold, and a graded boundary layer adjacent to and between the substrate and surface layer, wherein the graded boundary layer is an interdiffusion of the substrate and surface layer so that the graded boundary layer is between 0.5 wt. %-5.0 wt. % of the material making up the substrate, and between 99.5 wt. %-95.0 wt. % of the material making up the surface layer, and the graded boundary layer has a thickness of between 10%-90% of a shortest distance between the substrate and an exterior surface of the surface layer.

Abstract: A new electrochemical probe(s) design allowing for continuous (renewable) reagent delivery. The probe comprises an integrated membrane-sampling/electrochemical sensor that prevents interferences from surface-active materials and greatly extends the linear range. The probe(s) is useful for remote or laboratory-based monitoring in connection with microdialysis sampling and electrochemical measurements of metals and organic compounds that are not readily detected in the absence of reacting with the compound. Also disclosed is a method of using the probe(s).

Abstract: An apparatus or method of the present invention measures carbon monoxide included in a hydrogen-rich reactant gas with high precision, and also measures a lower alcohol or another organic compound included in the reactant gas. A carbon monoxide sensor (1) includes an electrolyte membrane (10), a pair of electrodes (12,14) arranged across the electrolyte membrane (10) to form a sandwich structure, a pair of holders (20,22) for supporting the sandwich structure as well as pair of metal plates (16,18), and an insulating member 24 for connecting the holders (20,22) with each other. A gas flow conduit (28) is joined with one holder (20), and a gaseous fuel is fed to the electrode (12) via the gas flow conduit (28). The electrode (14) supported by the other holder (22) is exposed to the atmosphere. A resistor (34) is connected to detection terminals (20T,22T) of the holders (20,22), and a potential difference between both terminals of the resistor (34) is measured with a voltmeter (32).

Abstract: A flow-through cell for extra-corporeal measurement of blood parameters has a pressure sensor arranged in a measurement chamber. The pressure sensor has an active pressure sensor part and an inactive pressure sensor part. The inactive pressure sensor part is constructed identically to the active pressure sensor part, and is insulated from the pressure prevailing in the measurement chamber by a rigid covering. The active and inactive sensor parts produce respective electrical signals which are subject to the same disturbing influences, so that by subtracting the signal of the inactive sensor part from the signal of the active sensor part, a measured value free of disturbing influences is obtained.

Abstract: A miniaturized circulatory measuring chamber with integrated chemo- and/or biosensor elements including a substrate formed from a plate-shaped carrier. Within the plate-shaped carrier is inserted at least one containment tapering from a frontal surface of the plate-shaped carrier toward a second surface. At least one plate is connected to the second surface. At least one duct-shaped cavity is in contact with a small opening of the containment.

Abstract: A disposable sensor for metal analysis comprises a housing including a first section, a second section, and a flexible intermediate section therebetween. An ampoule containing a reagent is disposed in the intermediate section. A liquid seal is formed between the first and second sections. The intermediate section of the housing of the disposable sensor may be flexed to break the ampoule. When the seal is broken between the first and second sections, and the water (or any other liquid) sample mixes with the reagent, the mixture flows into the second section containing an electrode assembly. The electrode assembly may be disposed in engagement with the monitoring device to determine the concentration of the at least one metal in the water (or any other liquid) sample.

Abstract: Method and apparatus for determining deterioration of e.g. lubricating oil by measuring the electrical properties of a polymeric matrix (support) holding charged ionic groups. The dynamic range of the device is increased by creating a local polar environment formed around the charged groups of the polymeric matrix and by exploiting bead shrinkage with increasing degradation (or solvent polarity). Both approaches can be further employed in a single sensor by the use of multiple chambers containing a combination of the above. Also, contaminant detection is improved by detecting changes in amplitude and/or frequency of noise output. The sensor can also be used to detect a level of oil for instance in an engine oil pan.

Abstract: Method and apparatus for determining deterioration of e.g. lubricating oil by measuring the contraction of a polymeric matrix (support) holding charged ionic groups. The support contracts due to oil quality degradation. The expansion/contraction is detected e.g. electrically.

Abstract: A method for detecting and identifying a chemical substance in various phases such as a vapor phase and a liquid phase. The chemical substance being measured is diffused into a predetermined phase. Then, an electric state at an electrode existing in the predetermined phase is detected as a change with time based on the diffusion and absorption of the chemical substance on the electrode. A pattern of the change of the electric state with time is prepared. A fitting function based on the pattern is set and parameters of the chemical substance being measured are found. A distance between the parameters of the chemical substance being measured and parameters of the reference substance which is detected is determined.

Abstract: An analyzer apparatus for analyzing components of a sample has a conduit and an electrochemical sensor in the conduit. The sample is passed through the conduit using a carrier liquid that is immiscible with the sample and non-wetting of the inner wall of the conduit to reduce instabilities in the apparatus due to undue fluid movement.

Abstract: A method for detecting organic molecules such as benzene, xylene, ethylbenzene and toluene present in trace quantities in aqueous solutions is provided. The method uses a zeolite having a multiple cage structure, specifically cages of two different volumes. The zeolite is chosen so that the organic molecules are able to access the zeolite on the basis of size. The small cages contain electroactive ions therein and the larger cages contain electroinactive counter cations therein. An aqueous liquid sample to be tested for small molecules is flowed into contact with the zeolite whereby at least some of the electroactive ions in the small cages are released into the aqueous liquid sample by small molecules entering the larger cages and coupling with the electroactive ions in the smaller cages and exiting the zeolite.

Abstract: A system for measuring the content of foreign substances in a gas stream, for example oil in a stream of compressed air. The system includes at least one probe for collecting a given amount of gas. In the probe there is at least one sensor over which the sampled gas is passed. For optimum evaluation and for signaling certain states of operation, the sensor includes a temperature sensor for determining the temperature of the gas sample flowing past it, and a detector whose electrical resistivity or conductivity depends on the nature and density of the foreign substances in the gas. The output signal of the detector corresponds to the concentration of foreign substance in the gas stream, and is processed in an electronic evaluation unit.

Abstract: A cell block for housing a sensor cell within a gas analyzer is mounted on the front panel of the analyzer, holding the sensor within a horizontal plane. The cell block is made of inexpensive and non-permeable material such as aluminum which is brazed and anodized. Entry and exit of sample gas is unique as is sample gas exposure to the sensor. Dead space is minimized and response time is improved. An insulated thermister in the cell block maintains accuracy over a wide range of temperatures. The device is RFI and EMI protected.

Abstract: The present invention is a sensor cartridge into which sensors are installed. The sensor cartridge allows the sensors to be easily and reliably installed into a blood analyzer. The sensor assembly has an electrical connector mounted on the rear side of the assembly. A plurality of inner walls within the housing locate a pump tube assembly and right angle fluid coupling within the housing. An opening in the housing receives a first boss which extends from the blood analyzer. A capture/release arm has an opening through which the first boss protrudes. The arm is resiliently held in place such that an inner edge of the opening is captured within a ring-like groove in the boss that extends from the blood analyzer when the cartridge is installed in the blood analyzer. A portion of the arm extends beyond the housing to allow an operator to press the arm and thus release the edge of the arm from the groove in the boss.

Abstract: An elastomer, especially a fluoropolymeric elastomer, meets requirements necessary for use as a gasket in contact with primary membranes of electrochemical sensors of both blood gas and ionic species in blood. The elastomer can electrochemically seal an electrode of a diced chip (sensor) from a sample chamber, and can electrochemically seal electrodes of neighboring diced chips from each other. Significant simplicity in fabrication of multi-sensor analyzers and stopped-flow method using such analyzers is realized.