40 results about "Amperometry" patented technology

A sensor, and methods of making, for determining the concentration of an analyte, such as glucose or lactate, in a biological fluid such as blood or serum, using techniques such as coulometry, amperometry, and potentiometry. The sensor includes a working electrode and a counter electrode, and can include an insertion monitoring trace to determine correct positioning of the sensor in a connector.

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.

<heading lvl="0">Abstract of Disclosure< / heading> A small volume sensor, and methods of making, for determining the concentration of an analyte, such as glucose or lactate, in a biological fluid, such as blood or serum, using techniques such as coulometry, amperometry, and potentiometry. The sensor includes a working electrode and a counter electrode, and can include an insertion monitoring trace to determine correct positioning of the sensor in a connector. In one embodiment, the sensor determines the concentration of the analyte by discharging an amount of charge into the sample, determining the time needed to discharge the charge, and determining the current used to electrolyze a portion of the analyte using the amount of charge and the amount of time.

The invention provides a preparation method and the application of an electrochemical micro-fluidic sensing chip. The preparation method comprises the following steps: directly coating an improved glass solution on a commercial standard printed electrode; and performing vacuum plasma treatment on a PDMS (Polydimethylsiloxane) chip with pre-designed pipelines and the printed electrode coated with the glass solution together, and directly bonding the PDMS chip on the commercial standard printed electrode to form a novel electrochemical microfluidic sensing platform. A sensor provided by the invention can perform ultrasensitive detection on various sample analytes in a biological fluid sample, taking the detection of a prostate cancer marker PSA (Prostate-specific Antigen) in human serum as an example, a coulomb amperometry is used for detection, and a result shows that the detection sensitivity can reach 0.84 pg / mL which is improved by two magnitudes than the standardized clinical testing requirement of 0.1 ng / mL, so that the sensor has superhigh detection sensitivity and accuracy, which are higher than those of other electrochemical detection devices, is convenient in operation, and can integrates sample processing, separation and the like on one micro electrochemical microfluidic sensing chip.

A method for determining a concentration of an analyte is disclosed. The method includes applying a potential excitation to a fluid sample containing an analyte and determining if a current decay curve associated with the fluid sample has entered an analyte depletion stage. The method also includes measuring a plurality of current values associated with the fluid sample during the analyte depletion stage and calculating an analyte concentration based on at least one of the plurality of current values.

This invention is a method for determining a concentration of an analyte. The steps include applying a potential excitation to a fluid sample containing an analyte, and measuring a current associated with the potential excitation at a plurality of time-points. The method also includes calculating an analyte concentration based on the measured current and a calibration curve, wherein the calibration curve is selected from a plurality of calibration curves and each calibration curve is associated with a time-segment selected from a plurality of time-segments.

In a method for calibrating a biosensor for the amperometric determination of creatinine in biological liquids, consisting of one electrode system each for measuring the concentrations of creatinine and creatine, with at least two calibration solutions being used, the electrode system for measuring the creatinine concentration is calibrated with a creatinine solution which, prior to the calibration measurement, was mixed in the form of an acidic solution with an alkaline buffer solution, and the electrode system for measuring the creatine concentration is calibrated with a solution in which creatinine and creatine are at a thermodynamic equilibrium.

This invention is a method for determining a concentration of an analyte. The steps include applying a potential excitation to a fluid sample containing an analyte, and measuring one or more currents associated with one or more time-segments. The method can also include calculating a final analyte concentration based on a first and second set of analyte concentrations, wherein each set of analyte concentration values is based on a first and second set of calibration data associated with first and second time-segments.

A sensor system, device, and methods for determining the concentration of an analyte in a sample is described. Gated amperometric pulse sequences including multiple duty cycles of sequential excitations and relaxations may provide a shorter analysis time and / or improve the accuracy and / or precision of the analysis. The disclosed gated amperometric pulse sequences may reduce analysis errors arising from the hematocrit effect, variance in cap-gap volumes, non-steady-state conditions, mediator background, under-fill, temperature changes in the sample, and a single set of calibration constants.

The invention discloses a two-dimensional metal organic framework nanosheet and a preparation method thereof. The preparation method comprises the following steps: adding a layered metal organic framework bulk material into a solvent, carrying out stripping under stirring, then carrying out standing to obtain a supernatant, and centrifuging the supernatant so as to obtain a precipitate, i.e., thetwo-dimensional metal organic framework nanosheet. The method provided by the invention can realize large-scale preparation of the two-dimensional metal organic framework nanosheet, and is convenientand practicable in operation. The two-dimensional metal organic framework nanosheet has a thickness of only 1 to 10 nm. The invention also discloses an application of the two-dimensional metal organicframework nanosheet in electrochemical detection of superoxide ions. Specifically, the two-dimensional metal organic framework nanosheet is made into a dispersion which is then subjected to drip-coating of an electrode, and then the superoxide ions are detected through a cyclic voltammetric method or / and an amperometric method. The two-dimensional metal organic framework provided by the inventionhas excellent electrocatalytic performance to the superoxide ions and is capable of converting the superoxide ions into water.

A sensor system, device, and methods for determining the concentration of an analyte in a sample is described. Gated amperometric pulse sequences including multiple duty cycles of sequential excitations and relaxations may provide a shorter analysis time and / or improve the accuracy and / or precision of the analysis. The disclosed gated amperometric pulse sequences may reduce analysis errors arising from the hematocrit effect, variance in cap-gap volumes, non-steady-state conditions, mediator background, under-fill, temperature changes in the sample, and a single set of calibration constants.

A method for measuring a concentration of an analyte in a bio-sample using an electrochemical bio-sensor according to an exemplary embodiment of the present invention is characterized by a step of obtaining predetermined features from induced currents obtained by applying a DC voltage according to chronoamperometry in which, after a whole blood sample is injected to the electrochemical bio-sensor, a concentration of an analyte is obtained from an induced current obtained by applying a DC voltage for a certain time and from all induced currents obtained by further applying several step-ladder perturbation potentials for a short time subsequent to the DC voltage for the certain time, and is also characterized by minimization of a measurement error caused by a hindering material by forming a calibration equation by combining the at least one feature in a function and optimizing various conditions of the bio-sample through DeletedTextsmultivariable analysis. With this configuration, a perturbation potential application method added to a conventional measurement method can maintain a bio-sensor and a measuring apparatus already used, a line used in the measuring apparatus, and calibration of amperometry as they are, improve accuracy in measurement by effectively minimizing a matrix interference effect of a background material in a bio-sample, particularly an inaccuracy caused by a change in hematocrit, and also remarkably improve accuracy in measurement by simply upgrading a measurement program of a conventional measuring apparatus.

The invention provides a preparation method and the application of an electrochemical micro-fluidic sensing chip. The preparation method comprises the following steps: directly coating an improved glass solution on a commercial standard printed electrode; and performing vacuum plasma treatment on a PDMS (Polydimethylsiloxane) chip with pre-designed pipelines and the printed electrode coated with the glass solution together, and directly bonding the PDMS chip on the commercial standard printed electrode to form a novel electrochemical microfluidic sensing platform. A sensor provided by the invention can perform ultrasensitive detection on various sample analytes in a biological fluid sample, taking the detection of a prostate cancer marker PSA (Prostate-specific Antigen) in human serum as an example, a coulomb amperometry is used for detection, and a result shows that the detection sensitivity can reach 0.84 pg / mL which is improved by two magnitudes than the standardized clinical testing requirement of 0.1 ng / mL, so that the sensor has superhigh detection sensitivity and accuracy, which are higher than those of other electrochemical detection devices, is convenient in operation, and can integrates sample processing, separation and the like on one micro electrochemical microfluidic sensing chip.

The invention discloses a preparation method of a graphene / graphene oxide microarray and application of the graphene / graphene oxide microarray used as a chemical and cell-based sensor. A graphene / graphene oxide microarray electrode is prepared on an ITO glass substrate by combining a micro processing technology and an electrochemical method. By utilizing the electrochemical catalytic oxidation of the microelectrode prepared by the invention on hydrogen peroxide, the in vitro and intravital quantitative analysis and detection of hydrogen peroxide are realized by a timing amperometry. The preparation method is simple and feasible, the sensitivity is high, the response time is short, the biocompatibility is good, and the concentration of hydrogen peroxide can be quickly detected.

The invention discloses a new method used for modifying a carbon fiber electrode with carbon nano tubes. The method comprises the step of depositing single-walled carbon nano tubes on a carbon fiber electrode by adopting an electrophoretic deposition method, wherein electrophoretic deposition is realized by virtue of a two-electrode system, and the method comprises the following specific steps: inserting the carbon fiber electrode and a Pt wire into single-walled carbon nano tube dispersion, applying a voltage of 1.9-2.5V by virtue of amperometry and performing electrophoretic deposition for 10-100s, thus the carbon fiber electrode modified by the uniformly deposited carbon nano tubes can be obtained. Before in vivo analysis is performed, high temperature and electrochemical simple treatment is performed on the carbon nano tube modified carbon fiber electrode, so that the electrode can have high selectivity and sensitivity on ascorbic acid and can be used for in vivo intracerebral in situ determination on change of concentration of ascorbic acid.