59 results about "Isotachophoresis" patented technology

This invention provides methods and devices for spatially separating at least first and second components in a sample which in one exemplary embodiment comprises introducing the first and second components into a first microfluidic channel of a microfluidic device in a carrier fluid comprising a spacer electrolyte solution and stacking the first and second components by isotachophoresis between a leading electrolyte solution and a trailing electrolyte solution, wherein the spacer electrolyte solution comprises ions which have an intermediate mobility in an electric field between the mobility of the ions present in the leading and trailing electrolyte solutions and wherein the spacer electrolyte solution comprises at least one of the following spacer ions MOPS, MES, Nonanoic acid, D-Glucuronic acid, Acetylsalicyclic acid, 4-Ethoxybenzoic acid, Glutaric acid, 3-Phenylpropionic acid, Phenoxyacetic acid, Cysteine, hippuric acid, p-hydroxyphenylacetic acid, isopropylmalonic acid, itaconic acid, citraconic acid, 3,5-dimethylbenzoic acid, 2,3-dimethylbenzoic acid, p-hydroxycinnamic acid, and 5-br-2,4-dihydroxybenzoic acid, and wherein the first component comprises a DNA-antibody conjugate and the second component comprises a complex of the DNA-antibody conjugate and an analyte.

This invention provides methods and systems for injection of analytes into a separation channel for resolution and detection. Samples can be preconditioned and concentrated by isotachophoresis (ITP) before the injection is triggered by a detected voltage event. Separation of analytes from other sample constituents can be enhanced using skewing channel ITP.

A method of separating components having a given negative or positive charge and contained in a sample is disclosed. The method involves, in one embodiment, loading a microchannel with a sample, placed between a trailing-edge electrolyte having a selected concentration of a titratable species, and a leading-edge electrolyte. With the application of a voltage potential across the microchannel, charged components in the sample stack by isotachophoresis, and electrolytic hydroxyl or hydrogen ions formed by electrolysis at the upstream-end electrode migrate into the trailing-edge ion buffer, titrating the titratable species therein, where the concentration of the titratable species in the trailing-edge electrolyte is selected , in relation to the lengths of the upstream channel region and sample-loading volume, to permit the sample to stack into a relatively small sample volume before electrolytic-ion migration from the upstream electrode into and through the sample-volume region is effective to overtake the charge sample components. With continued application of an electric potential across the channel ends, charged sample components in the stacked sample volume separated by zone electrophoresis.

A method and system are presented for fast and efficient isolation, purification and quantitation of nucleic acids from complex biological samples using isotachophoresis in microchannels. In an embodiment, a sieving medium may be used to enhance selectivity. In another embodiment, PCR-friendly chemistries are used to purify nucleic acids from complex biological samples and yield nucleic acids ready for further analysis including for PCR. In another embodiment, small RNAs from biological samples are extracted, isolated, preconcentrated and quantitated using on-chip ITP with a high efficiency sieving medium. The invention enables fast concentration and separation (takes 10s to 100s of seconds) of nucleic acids with high selectivity and using lower volumes of reagents (order of 10s of μL to focus less than 1 pg / μL of nucleic acid).

A method of simultaneously co-purifying and concentrating nucleic acid and protein targets is described. The method includes automation of the entire sample preparation process, performed by having an analyst add a sample into a device that performs all of the steps necessary to prepare a sample for analysis. The method provides for samples that are not split during the sample preparation process and where common purification methods can be used for purifying multiple analytes.

The invention provides a method for performing off-line multi-dimensional separation and analysis of a heterogeneous biomolecular sample. The method includes separating the heterogeneous biomolecular sample into a plurality of fractions using an, at least partially, capillary isotachophoresis mechanism. The plurality of fractions are then transferred to a liquid chromatography apparatus where they are each separated into a plurality of sub-fractions. The sub-fractions are then analyzed to determine their constituent molecules.

The present invention provides a method of indirectly detecting at least one directly undetectable analyte of interest. According to the method, a leading electrolyte and a trailing electrolyte are provided. In addition, a mixture of the at least one directly undetectable analyte and at least two directly detectable spacer molecules is provided. The directly detectable spacer molecules and the directly undetectable analyte are then concentrated and separated into zones using isotachophoresis. A displacement between the zones of directly detectable spacer molecules is then used to determine the presence of the directly undetectable analyte.

The invention relates to an operation mode of electrophoresis, which separates and / or fractionates particles of differentiated electrophoretic mobility. More specifically, the invention relates to isotachophoresis (ITP), including free-flow and capillary isotachophoresis, and provides novel electrophoresis methods, as well as kits and devices for carrying out such methods.

A method of simultaneously co-purifying and concentrating nucleic acid and protein targets into a single volume is described. The method includes automation of the entire sample preparation process, performed by having an analyst add a sample into a device that performs all of the steps necessary to prepare a sample for analysis. The method provides for samples are not split during the sample preparation process and where common purification methods can be used for purifying multiple analytes.

A method of simultaneously co-purifying and concentrating nucleic acid and protein targets into a single volume is described. The method includes automation of the entire sample preparation process, performed by having an analyst add a sample into a device that performs all of the steps necessary to prepare a sample for analysis. The method provides for samples are not split during the sample preparation process and where common purification methods can be used for purifying multiple analytes.

The invention discloses a functionalized microflow controlled chip and a method using the functionalized microflow controlled chip to analysis the PCR products. The chip comprises a buffering liquid pool, a waste liquid pool of buffering liquid, a sample injection waste liquid pool, a sample pool, a separating channel and a sample injection channel. Two ends of the separating channel are respectively connected with the buffering liquid pool and the waste liquid pool of buffering liquid. Two ends of the sample injection channel are respectively connected with the sample pool and the sample injection waste liquid pool. The length of the effective sample injection channel is 0.5cm to 20cm. the invention combines the isotachophoresis pre concentration and the screening electrophoresis separation. The buffering liquid contains a liac dielectric medium and a DNA screening medium. The method uses the chloride ion self contained in PCR products as a leading ion. The chip is only needed to be introduced in one type of buffering liquid, which reduces the number of the needed electrode and simplify the operation and has the advantages of sensitive and fast analyzing. The chip can effectively shorten the PCR reaction time through enhancing the detecting sensitivity. The invention can sensitively, fast and simply analyze the PCR products.

A method of simultaneously co-purifying and concentrating nucleic acid and protein targets is described. The method includes automation of the entire sample preparation process, performed by having an analyst add a sample into a device that performs all of the steps necessary to prepare a sample for analysis. The method provides for samples that are not split during the sample preparation process and where common purification methods can be used for purifying multiple analytes.

The present disclosure relates to devices and methods for performing isotachophoretic concentration of analytes using a porous matrix, for example, for use in diagnostic assays such as lateral flow assays. For example, the disclosure provides a method of concentrating an analyte in a sample. The method includes providing a device comprising a porous matrix having a first fluid pathway having a first end and extending to a second end, a first electrode, and a second electrode; introducing to the first pathway a first fluid comprising a trailing electrolyte, a second fluid comprising a leading electrolyte and the analyte; and applying a voltage across the first electrode and the second electrode for a time sufficient to provide an ITP plug. As described herein, the devices and methods described herein can be used in conjunction with lateral flow assay techniques to detect and quantify a variety of biochemical and biological analytes, such as nucleic acids, proteins, cells and metabolites.

The invention relates to a method and apparatus for carrier-free deflection electrophoresis, in which a separating media and a sample to be examined flow through a separating chamber between a pair of electrodes in a series of reversing bulk fluid flow along the direction of the electrodes, thereby separating the sample into zones which are to be collected into fractions for analysis or further processing. Among other things, the apparatus and method enable high-resolution separation of particles that can be performed in miniaturized chambers in electrophoresis modes including isoelectric focusing, zone electrophoresis, and isotachophoresis.

Gradient elution isotachophoretic apparatus, and systems for performing gradient elution isotachophoresis to separate, purify, concentrate, quantify, and / or extract charged analytes from a sample. The isotachophoretic apparatus include an electrophoretic assembly, a sampling assembly connected to the electrophoretic assembly, and / or a support structure connected to the electrophoretic assembly and / or to the sampling assembly. The system includes an isotachophoretic apparatus, and a controller communicatively coupled to the isotachophoretic apparatus. The controller includes a storage medium and a processor for executing computer readable and executable instructions.

Isotachophoresis (ITP) is exploited to control various aspects of chemical reactions. In a first aspect, at least one of the reactants of a chemical reaction is confined to an ITP zone, but the resulting product of the chemical reaction is separated from this ITP zone by the ITP process. In a second aspect, one or more reactants of a chemical reaction are confined to an ITP zone, and one or more other reactants of the chemical reaction are not confined to this ITP zone. In a third aspect, ITP is employed to confine at least one reactant of a chemical reaction to an ITP zone, and at least one reactant of the chemical reaction is delivered to the ITP zone in two or more discrete doses. These aspects are especially relevant to performing polymerase chain reactions using chemical denaturants as opposed to thermal cycling.

Method and materials to carry out preparative-scale electrophoretic separations based on the principle of dynamically created non-co-directional effective electrophoretic mobilities are disclosed. The primary application areas of the method are in the separation, purification, enrichment, concentration or conditioning of both small and large molecular weight, weak and strong electrolyte compounds, such as pharmaceuticals, oligo- and polypeptides, proteins, oligonucleotides, etc. These objectives can be achieved based on the use of a secondary chemical equilibrium, alone or in combination with multiple protic and other secondary chemical equilibria. Though such electrophoretic operations could be achieved by other means, such as by conventional zone electrophoresis or isotachophoresis, the method disclosed here can provide greater separation power, simplicity and higher production rates.

A paper-based micro fluidic device suitable for electrokinetics and particularly isotachophoresis (ITP) and a kit comprising same is provided. Further, a method for the preparation of said paper-based micro fluidic device and a method of use thereof for the detection and / or separation of molecules of interest are provided.

A DNA detection method combines DNAzyme reactions and on-chip isotachophoresis (ITP). A mixture of sample containing a target DNA and a DNAzyme sensor which is either (1) a catalytic molecular beacon or (2) a binary DNAzyme and a probe is loaded into a trailing electrolyte (TE) reservoir of a microfluidic chip. In the presence of the target DNA, the catalytic molecular beacon or the probe is cleaved to generate a fluorescent fragment. Enhanced DNAzyme reaction occurs at the TE-to-LE interface. Fluorescent signal from cleaved catalytic molecular beacon or probe is detected either at the location where DNAzyme reaction occurs or at a separate location. In the latter case, the microfluidic chip has a separation region containing a capture gel or a sieving matrix which allows the fluorescent fragment to pass through but captures or traps the uncleaved catalytic molecular beacon or probe.

An isotachophoresis method for preconcentrating and isolating a plurality n of charged analytes (Ai, with i=1 to n) contained in a sample is disclosed, wherein each one of the analytes Ai has an effective electrophoretic mobility μAi obeying the fully ordered relationship μA1>μA2>etc.>μAn, comprising the step of preparing a mixture of said sample and a number n−1 of spacer compounds (Sk, with k=1 to n−1) wherein each one of said spacer compounds (Sk) has an effective electrophoretic mobility μSk obeying the fully ordered relationship μAk>μSk>μAk+1. An axial electric field is applied along the longitudinal axis of a separation channel, thereby causing a preconcentration and separation of the analytes and spacers forming respective focused spacer zones and focused analyte zones that flow along the longitudinal axis. Each one of the spacer compounds (Sk) has an initial concentration (c0,Sk) selected in such manner as to substantially correspond, at its preconcentrated concentration (cSk) in the respective focused spacer zone, to a volume of the main separation channel enclosed between an associated pair of adjacent extraction channels (Ek) and (Ek+1). Through this spatial displacement of analytes Ai by spacers Sk, the analytes can be selectively extracted into the extraction channels Ei.

Disclosed herein is a device for separation and analysis of trace and ultra-trace ionogenic compounds by isotachophoresis-zone electrophoresis on a chip with online detection and method of its use, concentrating trace and ultra-trace analytes by isotachophoretic migration in a wide separation channel when a manifold of auxiliary electrodes is employed. Then the isotachophoretic zones of trace and ultra-trace analytes are transferred by isotachophoretic migration through a tapered channel, while corresponding auxiliary electrodes are progressively disconnected from the power supply. When the isotachophoretic zones enter the analytical capillary channel, the mode switches to zone electrophoresis and an online detector detects analytes for qualitative and quantitative analysis.

A method for separating electrically charged species contained in a solution by an isotachophoresis method applied in an electrophoresis device, the isotachophoresis method being coupled to isotopic measurement using a mass spectrometer. The method notably comprises a step of stopping the voltage applied to the terminal of the electrophoresis capillary and transient application of a counter-pressure making it possible to utilize the length of the capillary several times and extend the separation distance artificially.

A method for determining the molar concentration of specific lipoprotein particles present in a bodily fluid is presented. Multipixel Capillary Isotachophoresis Laser Induced Fluorescence is applied to fluorescently-labeled lipoproteins or immunologically-labeled apolipoproteins, facilitating quantification of lipoproteins and / or lipid particles and / or their associated apolipoproteins in a sample. The measurements are used to predict the risks of developing, progressing in severity of diseases related to lipoprotein particles, including cardiovascular and metabolic disorders.

A method for isotope measurement of charged species contained in a solution to be analyzed, particularly charged species having an isobaric interference, has the following consecutive steps:a) in the capillary of a capillary electrophoresis device, the solution to be analyzed is inserted contiguously between a terminating electrolyte and a leading electrolyte that, respectively, are placed after the inlet and before the outlet of the capillary and contain ions of the same charge but with mobility inferior and superior to those of said species;b) separating the species by using the capillary electrophoresis device according to the isotachophoresis mode; thenc) in the continuity of the preceding step, performing an isotope measurement of the species detected in the form of a substantially constant amplitude signal by using an inductively coupled plasma mass spectrometer (ICPMS) connected by direct coupling with the capillary electrophoresis device.

The invention relates to a method for trapping an organic compound in aqueous solution, which comprises the following steps of: taking inert metal materials as electrodes; adding precursor electrolyte aqueous solution, aqueous solution containing an organic matter to be trapped, ionic surfactant aqueous solution and following electrolyte aqueous solution into an electrolytic bath in turn, wherein the mobility of the ionic surfactant aggregate is less than that of the precursor ions in the precursor electrolyte and more than that of the following ions in the following electrolyte aqueous solution and the isotachophoresis condition is met as required; applying the DC voltage of 10V to 30kV; and when the ionic surfactant aggregate migrates to pass through the aqueous solution containing the organic matter to be trapped under the driving of an electric field, rapidly taking the surfactant-enriched solution out, namely trapping the organic compound in the aqueous solution. The method for trapping the organic compound in the aqueous solution has the application characteristics of avoiding combustible and toxic organic solvent, along with simple and convenient operation and low cost.

The present disclosure relates to fluidic systems and devices for processing, extracting, or purifying one or more analytes. These systems and devices can be used for processing samples and extractingnucleic acids, for example by isotachophoresis. In particular, the systems and related methods can allow for extraction of nucleic acids, including non-crosslinked nucleic acids, from samples such astissue or cells. The systems and devices can also be used for multiplex parallel sample processing.