Abstract: A fluid analyzer for analyzing fluid samples comprising one or more analytes and a method of calibrating such. The fluid analyzer includes a control system to control at least one automated valve to pass at least three calibration reagents through a fluid channel to a secondary ion selective electrode, a primary ion selective electrode, and a reference electrode, and determine calibration information using calibration logic from signals generated by a meter, control the at least one automated valve to selectively pass different subsets of the at least three calibration reagents through the fluid channel to the secondary ion selective electrode, the primary ion selective electrode, and the reference electrode, and determine re-calibration information using the signals generated by the meter and at least one of the calibration information and re-calibration logic.

Abstract: A fluid analyzer for analyzing fluid samples comprising one or more analytes and a method of calibrating such. The fluid analyzer includes a control system to control at least one automated valve to pass at least three calibration reagents through a fluid channel to a secondary ion selective electrode, a primary ion selective electrode, and a reference electrode, and determine calibration information using calibration logic from signals generated by a meter, control the at least one automated valve to selectively pass different subsets of the at least three calibration reagents through the fluid channel to the secondary ion selective electrode, the primary ion selective electrode, and the reference electrode, and determine re-calibration information using the signals generated by the meter and at least one of the calibration information and re-calibration logic.

Abstract: An apparatus and method for detecting cadmium using optical emission spectroscopy is provided. The apparatus contains a system which uses optical emission spectroscopy which is programmed and calibrated to detect the presence of cadmium in PPM. The system is calibrated using test samples which have been prepared with a lead/cadmium matrix material having at least one iron based electrode integrated therein.

Abstract: A substrate ion exchange system, along with methods of maintain such a system, is provided that includes a substrate having an outer region containing a plurality of substrate metal ions, an ion exchange bath that includes a plurality of first metal ions at a first metal ion concentration and a plurality of second metal ions at a second metal ion concentration, and a vessel for containing the ion exchange bath and the substrate. The ion exchange system also includes a temperature sensor coupled to the vessel, and a processor configured to receive a vessel temperature from the sensor and to evaluate the first metal ion concentration based at least in part on a first metal ion consumption rate relationship and the vessel temperature. Further, the first metal ion consumption rate relationship is predetermined.

Abstract: Methods and apparatus relating to very large scale FET arrays for analyte measurements. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes. In one example, chemFET arrays facilitate DNA sequencing techniques based on monitoring changes in hydrogen ion concentration (pH), changes in other analyte concentration, and/or binding events associated with chemical processes relating to DNA synthesis.

Abstract: Described herein are stable aqueous stannous ion containing compositions and methods of preparing and using the same.

Abstract: Compositions containing vinyl polymers and ionophores selective for lead ions (e.g., polypyrrole copolymers), and methods for making these compositions are disclosed herein. The compositions can, for example, be used for detecting lead ions in a sample.

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: An automatic method for identifying biological samples that are collected using the wrong blood preservative for subsequent analytical testing. The method also provides for identification and/or suppression of certain analytical test results that are substantially or partly adversely affected. The invention is particularly suited for use in point-of-care medical diagnostic testing.

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: Methods and systems for simultaneously measuring concentration of two or more different cations in solution. The methods include the steps of applying a steady state polarization technique to a solution comprising two or more different cations; measuring the limiting currents of the solution; and correlating the limiting currents with the concentration of the different cations. The system includes a working electrode; a potentiostat; a counter electrode; a reference electrode; a solution comprising different cations to be analyzed; and a model for correlating the limiting currents with the concentration of the pair cations. The working electrode may be any electrode compatible with the media, including noble metals, carbon, or combinations thereof. In some embodiments, the working electrode is a rotating disk electrode (RDE).

Abstract: A method of microanalyzing ions, which includes: placing in a cavity having an internal volume, a volume of an ionic liquid that is smaller than the internal volume; placing in the cavity a solution containing the ions that are to be analyzed, a solvent of the solution and the ionic liquid being selected so as to be immiscible and so as to enable the ions to be transferred from the solution to the ionic liquid; and detecting a presence of the ions in the ionic liquid with an analyzer that analyzes at least one of cations or anions of the ions in the ionic liquid, in a free state or in a complexed state, the analyzer being in contact with the ionic liquid.

Abstract: A system and method for voltammetric analysis of a liquid sample solution.

Abstract: An automatic method for identifying biological samples that are collected using the wrong blood preservative for subsequent analytical testing. The method also provides for identification and/or suppression of certain analytical test results that are substantially or partly adversely affected. The invention is particularly suited for use in point-of-care medical diagnostic testing.

Abstract: The evaporation of the stripping liquid 6 changes the concentration of the standard electrolyte. This causes the quantification accuracy of the chemical substance to be lowered. In order to solve the above problem, this invention provides a method for quantifying a chemical substance contained in a sample solution, characterized by the following stripping gel. The stripping gel covers the stripping electrode, and contains a standard electrolyte and an ionic liquid; however, the stripping gel contains no water. Furthermore, the ionic liquid is hydrophobic and nonvolatile, and the standard electrolyte is consisted of the anion and a metallic ion.

Abstract: Methods for cleaning and regenerating a working electrode in an electrochemical cell; method for measuring the concentration of a metal in a liquid sample in an electrochemical cell having a working electrode, the method including a step for cleaning and/or regenerating the electrode; and an assembly having an ultrasonic device in sonic communication with an electrochemical cell.

Abstract: The present invention is directed to a reversible electrochemical sensor for polyions. The sensor uses active extraction and ion stripping, which are controlled electrochemically. Spontaneous polyion extraction is suppressed by using membranes containing highly lipophilic electrolytes that possess no ion-exchange properties. Reversible extraction of polyions is induced by constant current pulse of fixed duration applied across the membrane. Subsequently, polyions are removed by applying a constant stripping potential. The sensors provide excellent stability and reversibility and allow for measurements of heparin concentration in whole blood samples via protamine titration. The sensors can also monitor a polyion concentration and an enzyme activity, wherein the polyion decomposition is directly proportional to the enzyme activity in a sample. Additionally, the sensors can monitor an enzyme inhibitor activity.

Abstract: An apparatus for a continuous, automated quantitation of tin compounds in liquid samples and a method for quantitative analysis based on the said apparatus are provided herein. The inventive apparatus acidifies liquid samples and in case organotin compounds are present in the sample, a selective UV irradiation converts the organotin compounds into inorganic tin. The inventive apparatus quantitates this inorganic tin by means of electrochemical methods. The apparatus and method of the present invention allow quantitative analyses of trace amounts of organic and inorganic tin compounds present in liquid samples by converting organotin, a form unsuited for measurement, into inorganic tin, a form amenable to measurements and performing electrochemical analysis. Above all, the present invention affords the construction of an automated, continuous analysis system, making unnecessary additional manual operations and reducing labor costs.

Abstract: Electrochemical methods and materials for the detection of arsenic. In one aspect, arsenic is detected using a working electrode comprising particulate platinum. In another aspect, arsenic is detected using an electrode comprising indium tin oxide and particulate gold. Also provided are methods for the production of electrodes which involve the electrodeposition of gold onto indium tin oxide.

Abstract: To reduce and homogenize the thickness of a semiconductor layer which lies on the surface of an electrically insulating material, the surface of the semiconductor layer is exposed to the action of an etchant whose redox potential is adjusted as a function of the material and the desired final thickness of the semiconductor layer, so that the material erosion per unit time on the surface of the semiconductor layer due to the etchant becomes less as the thickness of the semiconductor layer decreases, and is only from 0 to 10% of the thickness per second when the desired thickness is reached. The method is carried out without the action of light or the application of an external electrical voltage.

Abstract: A sampling system for measuring the presence and concentration of inorganic ion species, including, metals, metalloids and non-metals, in a liquid solution including a first sampling unit. The first sampling unit includes a potentiometric subsystem configured to gather environmental metrics of the liquid sample, a preparation subsystem, coupled to the potentiometric module, the preparation subsystem being configured to prepare and isolate contaminants of concern in a flow of a liquid sample into metal, metalloid, or non-metal ionic forms; and a voltammetric subsystem selectively coupled to the preparation subsystem, potentiometric subsystem and a sample source, the voltammetric subsystem being configured to identify and determine a concentration of metal, metalloid, or non-metal ionic species through stripping voltammetry. The system is configured to compare a value of a stripping signal of the sample with a predetermined value to determine if dilution of the sample is required.

Abstract: This invention provides an electrochemical analysis method for accurately detecting a harmful substance such as arsenic contained in a solution. In the electrochemical analysis method, a working electrode and a counter electrode are disposed in an object electrolytic solution. A negative potential is applied to the working electrode to electrodeposit the electrolyte onto the surface of the working electrode and thus to form an electrodeposit. Next, the potential of the working electrode is sweeped in a positive potential direction to allow the electrodeposit to elute into the solution and, at the same time, to detect a current change upon a potential change and thus to analyze an object substance dissolved as an electrolyte in the object electrolytic solution. A boron-doped electroconductive diamond electrode or an electrode with gold deposited on its surface is used as the working electrode.

Abstract: A method and device for the quantitative determination of an ion in a fluid which comprises subjecting the fluid to voltammetry using a sensing electrode which comprises an electrically conducting support having a surface which is coated with a support matrix, the support matrix containing an electroactive species capable of being oxidised or reduced to form a charged species, and an ionophore.

Abstract: An electrochemical suspended element-based sensor system includes a solution cell for holding an electrolyte comprising solution including at least one electrochemically reducible or oxidizable species. A working electrode (WE), reference electrode (RE) and a counter electrode (CE) are disposed in the solution. The CE includes an asymmetric suspended element, wherein one side of the suspended element includes a metal or a highly doped semiconductor surface. The suspended element bends when current associated with reduction or oxidation of the electrochemically reducible or oxidizable species at the WE passes through the suspended element. At least one measurement system measures the bending of the suspended element or a parameter which is a function of the bending.

Abstract: Methods and systems for simultaneously measuring concentration of two or more different cations in solution. The methods include the steps of applying a steady state polarization technique to a solution comprising two or more different cations; measuring the limiting currents of the solution; and correlating the limiting currents with the concentration of the different cations. The system includes a working electrode; a potentiostat; a counter electrode; a reference electrode; a solution comprising different cations to be analyzed; and a model for correlating the limiting currents with the concentration of the pair cations. The working electrode may be any electrode compatible with the media, including noble metals, carbon, or combinations thereof. In some embodiments, the working electrode is a rotating disk electrode (RDE).

Abstract: The present invention is directed to a reversible electrochemical sensor for polyions. The sensor uses active extraction and ion stripping, which are controlled electrochemically. Spontaneous polyion extraction is suppressed by using membranes containing highly lipophilic electrolytes that possess no ion-exchange properties. Reversible extraction of polyions is induced by constant current pulse of fixed duration applied across the membrane. Subsequently, polyions are removed by applying a constant stripping potential. The sensors provide excellent stability and reversibility and allow for measurements of heparin concentration in whole blood samples via protamine titration.

Abstract: Derivatised carbon is disclosed in which an amino acid or a derivative thereof is attached to the carbon. Derivatised carbon may be useful in the detection and removal of metal ions from liquid media.

Abstract: A device for use in assessing a flow condition of a fluid, or a fluid in a flow path, is provided. The device comprises at least one electrochemical cell, comprising a working electrode and at least one other electrode, sufficient for communication with the fluid, or sufficient for communication with a flow path, such that when sufficient fluid is in the flow path, the cell is in communication with the fluid. The fluid comprises a component sufficient to affect a mass-transport limited electrochemical reaction at the working electrode. The device also comprises at least one microcontroller operably connected to the at least one electrochemical cell for providing a potential or a current to the working electrode and for assessing the electrochemical reaction. A method of assessing a flow condition of a fluid, or a fluid in a flow path, is also provided. The device and the method of the present invention may be used in connection with the delivery of a fluid-borne or fluidized drug or medicament to a subject.

Abstract: Methods for studying ion channels comprise incorporating an ion channel onto the surface of a solid-supported membrane; applying a potential to the solid-supported membrane; and measuring an electrical signal of the ion channel. Methods for identifying or screening compounds that bind to ion channels employ an ion channel incorporated onto a solid-supported membrane.

Abstract: An electrode for use in analytical voltammetry, wherein the electrode has a uniform composition and contains an alloy in a solid state, the alloy containing a pure metal or compound having a low overvoltage for hydrogen and a few percent of at least one second metal or compound, wherein the electrode is a non-toxic electrode with a sufficiently high overvoltage for hydrogen allowing detection of a metal or compound to be detected. Also provided is an apparatus containing the electrode for performing analytical voltammetry involving a redox reaction at an electrode surface, and a method for increasing the utility of voltammetric analyses, by conducting the analyses with an electrode system containing the electrode.

Abstract: A sensor comprises: a pump cell comprising an inner pump electrode, an outer pump electrode, a pump cell electrolyte layer interposed between the inner pump electrode and the outer pump electrode and a cell isolation layer disposed on the inner pump electrode on a side opposite the pump cell electrolyte, wherein the outer electrode is in fluid communication with a reducing gas. A reference cell is in operable communication with the pump cell, the reference cell comprising an outer reference electrode and an inner reference electrode, and a reference cell electrolyte interposed between the outer reference electrode and the inner reference electrode.

Abstract: The present invention relates to methods for removing the matrix effects caused by variance in copper concentration and acidity during measurement of the organic additive concentration in a sample copper plating solution.

Abstract: The present invention relates to methods and apparatus for determining concentrations of various inorganic or organic components in solder plating solutions, which include titration or parallel titration methods, direct potentiometry methods, calibration methods, and/or UV-Vis absorption analysis.

Abstract: The present invention concerns a method for improving the sensitivity in measurements when performing electrochemical analysis containing low metal concentrations and a means for performing electrochemical analysis. Ordinary stirring has to be avoided during the voltammetric scanning due to the low reproducibility when stirring takes place. A sound exposure, however, can be performed during the entire measurement, increasing the sensitivity. Further it is concluded that sound exposure close to the resonant frequency, has improvement effects at least comparable to stirring, and thus all mechanical stirring can be avoided. It is found that audible sound in the low frequency range, around 100 Hz is very effective for this purpose, with an increase of the analytical signal up to about 300%, without any significant increase in the corresponding noise level.

Abstract: A hand-held portable drug monitoring system to detect and quantitate cocaine and other organic drugs in saliva, sweat, and surface wipes by using an ion selective electrode or an array of ion selective electrodes. The ion selective electrode has a cast membrane reference electrode and a sensing electrode with a hydrophobic polymer, a plasticizer, and an ionophore selective for the organic drug to be tested. The ion selective electrode can be connected to a converter that coverts a voltage reading from the ion selective electrode to a quantitative drug concentration level. Also disclosed is the related method of using an ion selective electrode to detect an organic drug in saliva, sweat, and surface wipes, the method of testing electrical contact in an ion selective electrode, and the method of making a cast membrane reference electrode.

Abstract: The present invention relates to methods and apparatus for determining concentrations of various inorganic or organic components in solder plating solutions, which include titration or parallel titration methods, direct potentiometry methods, calibration methods, and/or UV-Vis absorption analysis.

Abstract: An ammonium selective ionophore for use in ion selective electrodes.

Abstract: Method and apparatus for trace metal detection and analysis using bismuth-coated electrodes and electrochemical stripping analysis. Both anodic stripping voltammetry and adsorptive stripping analysis may be employed.

Abstract: The present invention relates to methods for removing the matrix effects caused by variance in copper concentration and acidity during measurement of the organic additive concentration in a sample copper plating solution.

Abstract: Improved dry-operative ion-selective electrodes and their use are described. The dry-operative ion-selective electrodes include an internal reference electrode comprising a water-soluble salt dispersed in a polymer binder consisting essentially of a monomer having at least one carboxyl group and a hydrophobic monomer. The polymer provides reduced brittleness, good interlayer adhesion and high salt tolerance.

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: A method of producing a silver halide photographic emulsion in which a silver ion concentration in precipitation of a silver halide emulsion in a precipitation bath is controlled, wherein a precipitation bath in which stirring is conducted rapidly and uniformly, and crystal formation and crystal growth are uniformly performed is used, the method comprises the steps of: in a start period of precipitation, quantitavely adding a silver nitrate solution and a halogen salt solution at a constant ratio flow rate; when an EAg value reaches a designated EAg value region in the vicinity of a preset target EAg value, starting a control of an adding rate of the halogen salt solution by using a controller which has an operation period equal to or shorter than 1 sec.

Abstract: A composite ion selective electrode comprising a calcium ion selective electrode member and a hydrogen ion selective electrode member which is characterized in that a calcium ion selective membrane of the calcium ion selective electrode member has a thickness of 5 to 30 &mgr;m, and the hydrogen ion selective membrane of the hydrogen ion selective electrode member contains tri-n-dodecyl-amine and trisethylhexyl trimellitate. Each of the calcium ion selective electrode member and the hydrogen ion selective electrode member can be employed singly.

Abstract: A method of screening a water soluble gold complex for use as a sensitizer in a silver halide photographic element comprised of experimentally measuring the electrochemical potential of the gold complex and then determining if the electrochemical potential falls within a predetermined utility window.

Abstract: An apparatus and method for the indirect determination of concentrations of additives in metal plating electrolyte solutions, particularly organic additives in Cu-metalization baths for semiconductor manufacturing. The apparatus features a reference electrode housed in an electrically isolated chamber and continuously immersed in the base metal plating solution (without the additive to be measured). An additive concentration determination method comprises electroplating a test electrode at a constant or known current in a mixing chamber wherein the base metal plating solution is mixed with small volumes of the sample and various calibration solutions containing the additive to be measured. Plating potentials between the electrodes are measured and plotted for each of the solution mixtures, and data are extrapolated to determine the concentration of the additive in the sample.

Abstract: An electrochemical sensor with a gelled membrane for prolonging the useful life of an ion-selective electrode. The gelled membrane is a hydrophilic membrane having a specially-formulated gel layer coated on one side. The gel-coated side of the gelled membrane is in intimate contact with the ion-selective membrane and separates the ion-selective membrane from the test samples and the calibration and cleaning fluids. The gelled membrane is a semi-permeable barrier which allows passage of the species to be measured while inhibiting the passage of surfactant and proteinaceous material into the polymeric ion-selective membrane.

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 first solution is brought into contact with a surface of a sample so that impurities, which exist in the sample or on the surface of the sample, and the sample are dissolved in the first solution, and a voltage is applied across electrodes by putting the electrodes into the first solution so that substances including the impurities are deposited on the surface of the electrodes, and the deposited impurities are dissolved in a second solution so that impurities dissolved in the second solution are measured. As a result, an impurity measuring method and an impurity measuring device, which are capable of measuring a very small amount of impurities with high sensitivity, which exist in the sample or on the surface of the sample, are provided.

Abstract: The accuracy and temperature-independence of ion-selective electrode meters having a logarithm resistance temperature correction incorporated therein is enhanced by using a microprocessor controlled and measured circuit with switched reference and switched capacitor filter, and by adding a linear membrane resistance term to the algorithm to improve accuracy across a wide temperature range.