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.

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.

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.

The invention discloses a microfluidic chip electrophoretic-electrochemical detecting device with adjustable pH after separation and use of the device in aminoglycoside antibiotics analysis. The analysis device comprises a double-T shaped sampling channel, a separating channel, two auxiliary channels, a W-shaped channel and an electrode placement channel. Through adding the two auxiliary channels and the W-shaped channel at the tail end of the separating channel in a microfluidic chip, an alkaline solution is added through the auxiliary channels after being electrophoretically separated, and the solution from the separating channel and the auxiliary channels is mixed evenly through the W-shaped channel, a pH value of the solution in a working electrode determining region is improved, so that the solution meets a strong alkaline condition needed by the detection of carbohydrates, simultaneously, electrophoretic separation under an acidic separation buffer solution is not influenced. By the device disclosed by the invention, a transition metal nano material is decorated on the surface of the electrode by using an electrodeposition method and by means of the relatively large specific surface area and the special catalytic property of the metal nano material, so that the working electrode with high performance is obtained, and aminoglycoside antibiotics are determined through the amperometry.

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 Deleted Texts multivariable 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 relates to a method for the electrochemical detection of sequence-specific nucleic acid oligomer hybridization events. To this end single DNA / RNA / PNA oligomer strands which at one end are covalently joined to a support surface and at the other, free end, covalently linked to a redox pair, are used as hybridization matrix (probe). As a result of treatment with the oligonucleotide solution (target) to be examined, the electric communication between the conductive support surface and the redox pair bridged by the single-strand oligonucleotide, which communication initially is either absent or very weak, is modified. In case of hybridization, the electric communication between the support surface and the redox pair, which is now bridged by a hybridized double-strand oligonucleotide, is increased. This permits the detection of a hybridization event by electrochemical methods such as cyclic voltametry, amperometry or conductivity measurement.

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 composite material modified electrode used for measuring glucose concentration and application thereof. According to the invention, firstly a polyamino acid modified electrode is prepared by virtue of a cyclic voltammetry, then the cyclic voltammetry is adopted for depositing metal nanoparticles on the surface of the polyamino acid film modified electrode, and a polyamino acid / metal nanocomposite material modified electrode is prepared. The obtained modified electrode is taken as a working electrode, a silver / silver chloride electrode is taken as a reference electrode, a platinum cylinder electrode is taken as an auxiliary electrode, and an amperometry is applied in a three-electrode system for realizing linear electrochemical response of glucose in a certain concentration range. The modified electrode has the characteristics of sensitive response and good stability.

A reagent composition containing GDH-PQQ as an enzyme-co-factor and screen-printed on working and counter electrodes of electrochemical biosensors, maintains activity of the enzyme reagents by proper selection of components. A preferred composition includes hydrophilic polymers, amorphous untreated silica, buffers, surfactants, and a mediator For example, the biosensor is useful in the amperometric determination of glucose.

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.

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.

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.

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 methods and systems according to the present invention overcome the high-frequency radiation and thermal interferences on an electrochemical sensor combined with long range radio communication. A Faraday cage is used to shield the sensor from the radiation in one embodiment. In another embodiment, a controller is installed between the sensor and the antenna to deactivate the antenna emission when the electrochemical sensor is conducting measurement. To control thermal interference, the temperature rise is controlled. The battery temperature is monitored and charging cycle is controlled. The temperature rises can also be avoided via intermittent use of the radio, heat sink strategies to direct heat away from the radio circuitry, and radio module construction designed to minimize heat emission. The present invention discloses an electrochemical sensor combined with a long range radio communication that has an improved accuracy due to having a better control of high frequency radiation and thermal interferences.

The invention relates to a polyrutin-silver nanoparticle-glassy carbon electrode and a preparation method thereof. The preparation method comprises the following steps: storing a glassy carbon electrode in an electrochemical electrolytic tank, wherein a supporting electrolyte of the electrochemical electrolytic tank is H2SO4 and contains rutin and AgNO3; and performing electrochemical deposition by adopting a timing ampere method to obtain the polyrutin-silver nanoparticle-glassy carbon electrode. The polyrutin-silver nanoparticle-glassy carbon electrode can be prepared by adopting an electrochemical deposition one-step preparation method, the steps are simple, and the operation is convenient; the electrode can rapidly detect various heavy metal ions in an environmental sample at the sametime, the heavy metals in different environmental samples (soil, water, hair and the like) can be rapidly detected, the sensitivity, the selectivity and the repeatability are good, the detection limitis low, the linear range is wide compared to the similar electrode in the prior art, and the significant difference does not exist in the detection of the heavy metals in the environmental samples compared to the widely-used inductively coupled plasma mass spectrometry analysis technology.

The invention relates to an electrochemical detection method for an endocrine disrupter on the basis of an enzyme nano-reactor. Through functionalized SiO2 as a template, graphene oxide is mixed therewith via hydrophobic-hydrophobic effect, then the materials are frozen and calcined to prepare graphene foam; then by means of electrostatic adsorption and covalent bond process at the same time, active enzyme is immobilized in pores in the graphene foam in order to establish a CYP3A4 / PNGF enzyme reactor. The invention discloses the electrochemical analysis method which is low in cost, has simpleoperations and is convenient and quick. The enzyme nano-reactor allows pore diameter to be adjusted, so that through amperometry, metabolic behavior of the endocrine disrupter can be quickly and accurately detected. The method has high sensitivity and stability and is suitable for promotion and application.

The invention belongs to the field of integrated circuit three-dimensional packaging, and particularly relates to a TSV electroplating filling additive constitutive model construction method and system. The method comprises the following steps: pretreating an electrode; preparing an electroplating basic solution and a to-be-tested additive, and injecting the diluted electroplating basic solution into a five-opening electrolytic tank; connecting an electrolytic tank circuit, and measuring a current-time curve of the electroplating basic solution before and after the addition of the additive under the action of different potentials by adopting a chronoamperometry method; performing normalization processing on the current density according to the current-time curve to obtain the coverage rate of the additive; and fitting the change rules of the additive coverage rate along with the additive concentration under different potentials, and constructing the constitutive equation according to the adsorption kinetics of the additive. The experimental steps are simple, the cost is low, and the obtained constitutive model is high in reliability.

The invention relates to a fructose nonenzymatic electrochemical sensor and a detection method thereof. Platinum-graphene oxide nanoflower is assembled on a working electrode to prepare a fructose sensor based on the processing; under a neutral solution condition, the fructose and the glucose have characteristics of different oxidation potentials under the effect of the platinum-graphene oxide nanoflower, and the fructose oxidation signal can be specifically recognized by using an electrochemical amperometry, thereby reaching an aim of detecting the fructose. The influence on a fructose detection result by an interferent is reduced when a self-reference recording method in a dual-working electrode mode is used for detecting fructose, and a faster method is provided for the detection of thefructose in the medical treatment and food industry.

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.