Abstract: A miniature reference electrode with improved stability and durability formed of a miniature silver/silver chloride reference electrode with high stability and general applicability as a reference electrode. The miniature reference electrode includes, on electrode substrate, a thin-film backbone metal pattern and a thin-film silver pattern formed in electrical contact with a portion of the thin-film backbone metal pattern. A silver chloride layer is set on a portion of the thin-film silver pattern. The silver chloride layer is in contact with a portion of thin-film electrolyte layer via hydrophobic thin-film insulating layer. The thin-film electrolyte layer is impregnated with a saturated solution of potassium chloride for making contact to the outside via a thin-film liquid junction pattern. When in use, the thin-film liquid junction pattern (31) is impregnated with the electrolyte, while its end portion is recessed in an aqueous solution.

Abstract: Disclosed is a NOx sensor for measuring a NOx concentration comprising a main pumping cell and a detecting electrode, the main pumping cell including an electrode (an inner pumping electrode and an outer pumping electrode) having no decomposing/reducing ability for NOx or a low decomposing/reducing ability for NOx, to be used so that an oxygen concentration in a measurement gas is controlled 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.

Abstract: A method for spectrographically providing a chemical profile of mammalian cells in vitro using capillary (10) electrophoresis is described. The method enables rapid determination of the chemicals, especially human cell metabolites, in the case of diabetes. The method is rapid, efficient and reproducible and enables the diagnosis of the progress of a disease at the cellular level.

Abstract: The present invention is drawn generally to an improved electrochemical sensor. The reference cell within the sensor can be a salt bridge comprising at least two chambers for containing an electrolyte fluid, preferably containing a semipermeable plug impregnated with an electrolyte, an essentially fluid impermeable plug for separating the at least two chambers, and a narrow opening through the plug providing a non-axial flow path for ionic communication between the at least two chambers when the electrolyte fluid is present.

Abstract: The present invention relates to apparatus and a method for measuring ammonia in biochemical processes, and more particularly to apparatus for real time measuring the amount of ammonia in a liquid with or without suspended solids.

Abstract: The present invention relates to a biosensor comprising a working electrode base plate 11, a counter electrode base plate 14 and a reagent layer containing at least an enzyme and an electron mediator, wherein a working electrode 12 disposed on the working electrode base plate and a counter electrode 15 disposed on the counter electrode base plate are positioned so as to mutually face and a terminal of a measuring device can be brought in contact with terminals 13, 16 of both electrodes from through-holes 25, 24. Such a biosensor can produce highly reliable and accurate measuring results with only a small amount of a sample.

Abstract: A polymeric material which to form a stable, reproducible interface between the ionic and electronic domains of an ion selective sensor, or an ion selective field effect transistor, or the like is provided. When employed in an ion selective sensor, the polymeric material is advantageously provided over a solid internal reference electrode and an ion selective material is provided thereover. According to one embodiment, the polymeric material of the invention includes less than about 1.63×10<immobilized charged sites per gram (less than about 2.72 millaequivalents/gram). According to another embodiment, the polymeric material includes immobilized sites of charge opposite that of mobile ions involved in the redox couple. A preferred polymeric material comprises a copolymer of methacrylamidopropyltrimethylammoniumchloride and methylmethacrylate.

Abstract: The present invention relates to a novel method and apparatus for the amperometric determination of an analyte, and in particular, to an apparatus for amperometric analysis utilizing a novel disposable electroanalytical cell for the quantitative determination of biologically important compounds from body fluids.

Abstract: A method for electrochemical detection (ECD) is disclosed. The illustrated embodiments are particularly adapted to use in detection of analytes separated by capillary electrophoresis. The method is a voltammetric ECD, including a preparatory positive potential pulse, an optional stabilizing pulse at a negative potential, an analytical pulse at extreme negative potentials (e.g., −300 mV to −1,500 mV), and a positive cleaning potential pulse. The methods have been shown to detect analytes previously considered to be electrochemically inactive using more traditional electrochemical methods. Examples of such analytes include various drugs, antibiotics, and peptides.

Abstract: A disposable plate electrode with biological active film is used to cooperate with a biological sensor for analyzing composition and measuring concentration of a test sample according to electric effect resulted from a biochemical reaction. The plate electrode comprises at least an electrode portion for transmission of the electric effect as well as a biological active film that reacts with the test sample chemically or biochemically. The biological active film contains a carrier layer (cellulose, for example) for adsorbing and keeping the biological active substance (enzyme, for example), which, the carrier layer, can change the electrode portion from hydrophobic into hydrophilic and protect the biological active substance against impairment during relatively higher temperature drying process.

Abstract: In a microfluidic system using electrokinetic forces, the present invention uses electrical current or electrical parameters, other than voltage, to control the movement of fluids through the channels of the system. Time-multiplexed power supplies also provide further control over fluid movement by varying the voltage on an electrode connected to a fluid reservoir of the microfluidic system, by varying the duty cycle during which the voltage is applied to the electrode, or by a combination of both. A time-multiplexed power supply can also be connected to more than one electrode for a savings in cost.

Abstract: An enzyme electrode sensor and a fabricating method thereof, and more particularly, an enzyme electrode sensor which is a biosensor using electrochemical measurement and a manufacturing method thereof. The sensor includes an electrode, a first nonconducting polymer layer formed by electropolymerization outside the electrode wherein enzyme is immobilized in the nonconducting polymer layer, a second nonconducting polymer layer in which enzyme is not immobilized, the second nonconducting layer formed by electropolymerization outside the first nonconducting polymer layer, and an outer layer formed outside the second nonconducting layer. The sensor selectivity is improved as the interference of organic materials is inhibited, and the interference of acetaminophen causing the major problem with a glucose sensor is controlled effectively by the sensor.

Abstract: A nitrogen oxide gas sensor wherein an alloy electrode of platinum and rhodium or a cermet electrode of platinum, rhodium, and zirconia or of a rhodium alloy and zirconia is used as the gas sensing electrode. The electrode of the sensor is suitable for measuring nitrogen oxide such as NO and NO2 in an exhaust gas.

Abstract: An improved cassette for use in the formation of an electrophoretic gel comprises two plates with substantially planar walls having two sides and two ends so arranged in a side by side spaced apart array to form a gel receiving space between them. A plurality of dividing ribs on one or each of the walls extend from a first end of the wall or walls substantially parallel to at least one of the sides thereof to a rib base end. The ribs extend into the space so as to subdivide at least one end of the space into a plurality of substantially parallel wells. A plurality of holes extend through at least one of the walls of the cassette located at or adjacent the base of the dividing rib and aligned with the rib. The arrangement of holes allow sufficient current flow to replace that lost due to the dividing ribs.

Abstract: A sensor is provided that includes at least one functional coating layer that includes a UV-absorbing polymer. Methods for making the inventive sensors are also provided.

Abstract: A sensor element has a solid electrolyte body holding a reference gas side electrode and a measurement gas side electrode on surfaces thereof. The measurement gas side electrode is covered with a porous protective layer including a component as a lead getter, which reacts with lead contained in measurement gas. Accordingly, lead is removed from measurement gas by the protective layer not to be attached to the measurement gas side electrode. As a result, the sensor element can be used in measurement gas containing lead, without deteriorating responsibility and output thereof.

Abstract: A modular, in particular multidimensional system for the reagent-free, continuous detection of a substance is disclosed. The system is characterized by the presence of at least two measurements modules of preferably different types. The modules are robust and designed for a long-time operation. They have an exchangeable or replaceable selective layer structure. The system may also include appropriate modules for amperometry and optical sensors.

Abstract: Apparatus and methods for aspirating and dispensing reagents are provided. Aspirating of reagents is accomplished by a probe, a vial insert and reagent vial according to the present invention wherein a seal is formed between the probe and the vial insert when the probe engages the vial insert. Dispensing of reagents is accomplished by a probe and a probe dispense and wash station according to the present invention wherein a seal is formed between the probe and the vial insert when the probe engages the probe dispense and wash station.

Abstract: The invention provides a novel “in situ” loader for electrophoretic gels. The loader comprises a body, containing at least one passage with an inlet and an outlet, and at least a part of the loader can be inserted into a gel holding portion of an electrophoresis apparatus. The loader can be loaded with samples, a variety of protocols performed without having to remove the samples, and electrophoresis performed directly from the loader into a gel. Centrifuges and PCR blocks adapted to accept the loader are also provided. The invention is particularly suited for use in automating DNA sequencing.

Abstract: An apparatus and process for producing a homogeneous analytical sample from a heterogenous feedstock by: providing the mixed feedstock, reducing the temperature of the feedstock to a temperature below a critical temperature, reducing the size of the feedstock components, blending the reduced size feedstock to form a homogeneous mixture; and obtaining a representative sample of the homogeneous mixture. The size reduction and blending steps are performed at temperatures below the critical temperature in order to retain organic compounds in the form of solvents, oils, or liquids that may be adsorbed onto or absorbed into the solid components of the mixture, while also improving the efficiency of the size reduction. Preferably, the critical temperature is less than 77 K (−196° C.). Further, with the process of this invention the representative sample may be maintained below the critical temperature until being analyzed.