59 results about "Isotachophoresis" patented technology

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.

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 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.

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 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 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.

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 kit for separating and concentrating nucleic acid and protein targets includes labeled reagents which affect simultaneous co-purification and concentration of a nucleic acid and a protein, a gel isotachophoresis separation unit to which a sample comprising the nucleic acid and the protein is added, a detection unit for the detection of the presence of the nucleic acid and the protein, and instructions for use. The gel electrophoresis includes a gel box having a negative electrode side and a positive electrode side, the negative electrode side being filled with a first buffer comprising 2-Hydroxy-N-(tris(hydroxymethyl)methyl)-3-aminopropanesulfonic acid buffer and the positive electrode side being filled with a second buffer being different than the first buffer. The gel isotachophoresis separation is configured to subject the sample to isotachophoresis using a voltage.

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 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.