3932 results about "Solid phase extraction" patented technology

Fluid-handling methods and devices for ultrasonic manipulation of fluid-borne particles comprise a fluid-handling manifold and an ultrasonic particle manipulator defining an ultrasonic cavity within the manifold. Fluid-borne particles introduced into the manifold are manipulated by controlling ultrasonic standing waves at the ultrasonic cavity. Cavities having non-uniform configurations, asymmetric standing waves and / or multiple ultrasonic cavities within the manifold are operative to control the movement of the fluid-borne particles, optionally including collecting and holding such particles, transferring particles through an intersection from one channel to another, etc. Solid phase extraction (SPE) particles, biological particles and other fluid-borne particles can be manipulated within the fluid-handling manifold.

The invention discloses hot pepper and a determining method for 96 pesticide residues in a product of the hot pepper. The determining method comprises the following steps: homogenously extracting residual pesticide in a sample with 1% acetic acid-acetonitrile solution, purifying the extracting solution with a Florisil solid phase extraction column, dispersing and purifying the extracting solution with ethylenediamine-N-propyl silane (PSA) and octadecyl silane bonded phase (C18) substrate, detecting 69 pesticide residuals in the purified concentrated liquid of the Florisil column by GC-MS (gaschromatographic mass spectrometry), detecting 27 pesticide residuals in the substrate dispersed purified liquid by liquid chromatography-tandem mass spectrometry (LC-MS / MS), using the black substrate solution dilution standard to construct the updated calibration curves, adopting an internal standard method to quantify when using GC / MS to detect the residuals, and adopting an external standard method to quantify when using LC-MS / MS to detect the residuals. The average recovery rate of the method is 70.7-118.6%; the average relative standard deviation (RSD) is 3.2-11.4%; the detection limit is 0.13-28.2 ug / kg. The determining method has the advantages of simplicity and convenience in operation, high speed, accuracy, high sensitivity and good repeatability.

The present invention provides an on-chip packed reactor bed design that allows for an effective exchange of packing materials such as beads at a miniaturized level. In accordance with the present invention, there is provided a method of concentrating an analyte within a microfluidic analysis system, comprising the steps of: a) providing a main channel having a trapping zone suitable for trapping packing material; b) providing a slurry of a reagent treated packing material prepared in a solution having a predetermined composition of a solvent; c) inducing a flow of said packing material into said trapping zone through a flow channel connected to said trapping zone so as to load said trapping zone and form a packed bed of said packing material; d) and flowing a sample containing analytes through said packed bed, said reagent acting to concentrate at least some of said analytes within said trapping zone. The present invention extends the function of microfluidic analysis systems to new applications including on-chip solid phase extraction (SPE) and on-chip capillary electrochromatography (CEC). The design can be further extended to include integrated packed bed immuno- or enzyme reactors.

Microliter scale solid phase extraction devices for preparing analytes in microliter volumes are disclosed. A re-useable device is provided in cartridge form that includes a central containment member with a containment bore that holds as little as 1 to 5 μl or less of a solid phase material that binds the analyte. The containment bore is enclosed on either side by a porous membrane that has an inner portion exposed for fluid flow and a peripheral portion that is sealed against fluid flow. The seal is formed by engaging the periphery of the porous membranes between sealing surfaces of the central containment member and corresponding sealing surfaces on first and second conduit assemblies that comprise the remainder of the cartridge. A non-reuseable device is provided in “chip” form, which includes a porous filter sandwiched between top and bottom wafers each having a plurality corresponding input and output conduits for a plurality of samples.

The present invention is directed to a system for pre-treatment of a sample to be introduced in a chromatograph, and a method for performing solid-phase extraction of a component present in a sample. The system uses a syringe having a needle being provided with a porous body having a monolithic structure along at least an appropriate length of the needle and across an overall diameter of the needle. The method includes the steps of inserting the needle into the sample, passing the sample through the needle to retain an analyte within the porous body, and desorbtion of the retained analyte from the porous body.

The invention relates to the fields of analytical chemistry and food safety, in particular to a method for detecting the residual quantity of multiple alkaline drugs in animal derived food. Based on the vortex mixed extracting of acetonitrile, isopropanol and citric acid buffer solutions, the purification of a hydrophilic polystyrene-divinylbenzene solid phase extraction column and a cation exchange solid phase extraction column and the liquid phase chromatography-mass spectra determination, the method can detect the residual quantity of multiple alkaline drugs in pork, pork liver, eggs, shrimps and milk, such as beta-receptor agonists,sulfonamides, benzodiazepines, nitroimidazoles, benzimidazoles and triphenylmethanes. The method has the advantages of simple operation, fast and accurate detection and high efficiency.

The present invention provides an on-chip packed reactor bed design that allows for an effective exchange of packing materials such as beads at a miniaturized level. The present invention extends the function of microfluidic analysis systems to new applications including on-chip solid phase extraction (SPE) and on-chip capillary electrochromatography (CEC). The design can be further extended to include integrated packed bed immuno- or enzyme reactors. The system comprises two weirs (6, 7) in a channel to trap packing material (12). The packing material might be introduced through a side channel to the chamber formed between the two weirs (6, 7). A plug is positioned in the side channel to close it.

A composition, method and device for the preparation of biological samples for subsequent LC-MS analysis using a combined and concurrent protein precipitation and solid phase extraction (SPE) process is described. Through an integrated combination of protein precipitation, filtration, and SPE using a novel zirconia-coated chromatographic media, interfering compounds, such as proteins and phosphate-containing compounds, are eliminated from the biological samples, affording a higher degree of analyte response during LC-MS analysis.

The present invention is a disposable apparatus for the rapid, low-volume solid phase extraction of analytes from a variety of sources. The apparatus of the present invention is configured as a pipette tip and contains a loosely confined stationary phase. The mobility of the stationary phase particles enables rapid mixing and equilibration with a sample solution during agitation. The analyte may thereby be extracted in less time with less solvent, removing the need for a separate concentration step.

The present invention relates to a method of simultaneously detecting a plurality of agro-veterinary drug residues in bee products. The extracted liquid trichloroacetic acid or perchloric acid and the extracted liquid acetate, phosphate or borate solution are added into a sample; the pH value is controlled between 4.5 and 9.0; the mixed solution is centrifuged, the filtrate is added into a solid phase extraction column to be extracted, the extraction column is eluted and dried, the column is washed by oxalic acid-methanol solution, the volume of the eluent is defined by the aqueous solution of methanol, the eluent is added into liquid chromatography-tandem mass spectrometry to be analyzed and tested, the acquired chromatographic peak is contrasted with the known standard chromatographic peak of the drug, and according to the retention time and the abundance of the mass spectrum ions, the specific name of the detected drug is determined. The method only requires one pre-treatment of the sample, and thus can simultaneously extract 11 classes and more than 60 kinds of veterinary drug residues, such as sulfonamides, quinolones, macrolides, lincomycins, nitroimidazoles, beta-lactams, tetracyclines, chloromycetins, trinethoprims, chlordimeform, triadimenol and the like, the efficiency of analysis is high, and the detection cost is greatly reduced.

The invention relates to a method for measuring tobacco-specific nitrosamines (TSNAs for short) by using a super efficient liquid chromatogram-tandem mass spectrum combined method, and belongs to a method for detecting TSNAs. The method comprises the following steps of: adding internal standard-containing aqueous solution of ammonium acetate into a filter sheet after trapping smoke and cigarette filters smoked completely under standard conditions or tobacco shreds, performing ultrasonic extraction, transferring 1 to 2mL of extract into a small solid-phase extraction column taking N-vinyl pyrrolidone-benzene sulfonic acid copolymer as filler, flushing the small column by using aqueous solution of methanoic acid and methanol, finally eluting the small column by using solution of aqueous ammonia and methanol solution, analyzing the eluant by using an ultra performance liquid chromatography-mass spectrometer / mass spectrometer (UPLC-MS / MS), and quantifying according to the area ratio of a component peak to an isotope internal standard peak. The detecting method can be used for detecting the TSNAs in cured and hybrid cigarette mainstream smoke, cigarette side-stream smoke, filter tip intercepting smoke and tobacco shreds, and has the advantages of simple pretreatment, accurate quantification, high instrument analysis speed, low detection limit, high sample treatment flux and the like.

The invention discloses a full-automatic modular multi-sample intelligent processing system, which comprises a liquid adding and homogenizing module, an automatic vacuuming and filtering module, an automatic nitrogen blowing and concentrating module, an automatic gelatum permeating and purifying module, an automatic slide phase extracting module, an automatic transmitting and heating module and an operation control module. Corresponding processing modules, experimental condition procedures and operation procedures are edited and selected by the operation control module according to the needs of different samples to be processed to carry out corresponding automatic processing. The full-automatic modular multi-sample intelligent processing system can synchronously process four samples, can continuously process fixteen samples, and carry out processing procedures of liquid adding, homogeneity extraction, filtration, gelatum purification, solid phase extraction, nitrogen blowing on the samples. The full-automatic modular food residual sample processing system realizes full automation of processing the samples, effectively improves the sample processing quantity, simplifies the operation process, improves the detection quality and improves the experimental safety.

The invention relates to a preparation method of covalent organic framework composite microspheres with core-shell structures. The method comprises the following steps: dissolving silicon dioxide microspheres, a first construction element and a second construction element in an organic solvent; and after adding a catalyst, rapidly synthesizing into the composite microspheres with core-shell structures at a certain temperature. In a preparation process, reaction conditions are gentle, the method is simple, and the yield is high; the prepared covalent organic framework composite microspheres have the advantages of good core-shell morphology, high specific surface area, ordered pore structures, good mechanical stability, thermal stability, chemical stability and the like, if the microspheres are used as a chromatographic stationary phase, the chromatographic mass transfer resistance can be reduced effectively, the theoretical plate height is improved, and finally, column efficiency and degree of separation are improved; and if the microspheres are used as solid-phase extracting filler, the enrichment effect can be improved remarkably. The covalent organic framework composite microspheres with core-shell structures have good application prospects in the aspect of separation and enrichment of small organic molecules.

The invention provides, inter alia, methods of extracting an analyte from a solution comprising the steps of: passing a solution containing an analyte through an extraction channel having a solid phase extraction surface, whereby analyte adsorbs to the extraction surface of said extraction channel; purging bulk liquid from said extraction channel; and eluting the analyte by passing a desorption solvent through the channel. The invention further provides reagents, columns and instrumentation related to this and other methods.

The invention discloses a triazine weedicide, and metabolite molecular engram polymer microspheres, a preparation method and an application thereof, which relate to molecular engram polymer microspheres and a preparation method and an application thereof and are used for solving the problem that the conventional molecular engram polymer can only specially absorb one kind of substance and realizing the effect of separating and enriching a plurality of triazine pesticide residues in a sample respectively. The molecular engram polymer microspheres are prepared by the following steps of: dissolving double template molecules and methacrylic acid into acetonitrile; oscillating; adding trimethylolpropane trimethylacrylate and azobisisobutyronitrile; performing ultrasonic treatment, charging nitrogen, removing oxygen and sealing; and heating in a constant-temperature water bath, cooling, grinding, sieving, eluting and drying. The molecular engram polymer microspheres are applied to a filling material of a solid phase extraction column. A product obtained in the invention has the advantages of high specificity, large absorption amount, wide application range, simple method and low cost. High specific separating and enriching characteristics on the triazine weedicide are achieved, the recovery rate is 65-110 percent, and the requirement of multiple residues can be met.

Solid phase extraction devices for sample preparation are disclosed, comprising a hollow conical tube having one narrower opening and one broader opening, wherein the narrower opening of the tube contains a solid phase extraction material comprising a functionalized monolithic sorbent, and wherein the solid phase extraction device is prepared by a combination of reduced pressure, positive pressure and mechanical compaction. The solid phase extraction devices are adapted for preparation of small sample volumes, and provide excellent recovery of analytes and good flow characteristics. Methods for preparing and using the solid phase extraction devices are disclosed.

The subject invention provides chemical compositions and synthesis strategies to create molecularly imprinted polymers (MIPs) via sol-gel processes. In a specific embodiment, the subject invention utilizes a(n) organic, inorganic, or metallic template analyte to create a hybrid organic-inorganic or inorganic three-dimensional network possessing cavities complementary to the shape, size, and functional orientation of the template molecule or ions. The subject invention further pertains to the use of the novel MIPs as selective solid phase extraction (SPE) sorbents for pre-concentration and clean-up of trace substances in biological and environmental samples. Synthesis of other molecularly imprinted polymers with environmental, pharmaceutical, chemical, clinical, toxicological, and national security implications can be conducted in accordance with the teachings of the subject invention.

A method for separating heavy oils by solid phase extraction comprises the step of the contact of the heavy oils with stationary phase, wherein the stationary phase consists of silica loaded with silver ions and alumina. In the method, solid extraction separation is used to separate the heavy oils to obtain saturated hydrocarbon, aromatic hydrocarbon, and colloid, and then the saturated hydrocarbon, the aromatic hydrocarbon and the colloid are prepared. By using the method, the separation efficiency and the handling capacity can be taken into account, and the rapid and efficient separation of the heavy oils is realized.

The invention discloses a molecularly imprinted polymer and a preparation method and application thereof. The molecularly imprinted polymer of the invention is the molecularly imprinted polymer, which is prepared by using ractopamine as a template, polymerizing the template with a functional monomer, a cross-linking agent, a pore-forming agent and an initiator to form a block polymer, grinding the block polymer, sieving the obtained powder, removing the template by using acetate methoxide and methoxide and carrying out vacuum drying on the obtained product and has high compatibility and obvious selectivity for the ractopamine. The molecularly imprinted polymer of the invention has high compatibility and selectivity for the ractopamine and has wide application prospect in analysis of a sample pretreatment solid phase extraction material of the ractopamine in substrates such as a feed, animal tissue or environment water and the like.

The invention belongs to the field of food inspection, relates to an assay determination method for endocrine disruptors in food, and particularly relates to a method for analyzing and determining a plurality of endocrine disruptors in milk powder and liquid milk. The method comprises the steps of dissolving a sample with water, adding an organic solvent mixable with water, extracting a to-be-detected material by ultrasonic, adding a sodium salt to make the organic solvent separated from a water phase to realize liquid-liquid extraction, taking an organic solvent containing quantitative to-be-detected material, purifying by extraction with a solid phase filled with C 18 materials, deriving by dansyl chloride, and analyzing and detecting four types of 26 endocrine disruptors in the food by using ultra-high performance liquid chromatography-quadrupole-time of flight-mass spectrometry at the same time. The method can overcome the disadvantages that a conventional technology cannot realize simultaneous analysis of the plurality of the endocrine disruptors in the food by once chromatographic sample injection, can increase sensitivity of the quadrupole-time of the flight-mass spectrometry, and realize accurate analysis of the endocrine disruptors in the food by using the quadrupole-time of the flight-mass spectrometry.

The invention discloses a preparation method of a magnetic metal organic framework material and an application of the magnetic metal organic framework material. The preparation method comprises the steps of synthesizing a nano magnetic material Fe3O4 by adopting a coprecipitation method, adding the nano magnetic material Fe3O4, FeCI3.6H2O and terephthalic acid into DMF, carrying out ultrasonic mixing, and synthesizing Fe3O4 / MIL-101(Fe) by adopting a hydrothermal method; separating a product by utilizing a magnetic field, washing with hot ethyl alcohol, and drying overnight so as to obtain the Fe3O4 / MIL-101(Fe). The Fe3O4 / MIL-101(Fe) obtained by the method is applied to separating and enriching organophosphorus in urine. The magnetic metal organic framework material is uniform in particle size, is relatively strong in magnetism, and is good in dispersibility; MIL-101(Fe) formed by the coordination of oxygen bearing carboxylate ligand and a metal ion F3<3+> is adopted as an adsorption separation medium and is combined with a magnetic solid phase extraction technique for being combined with chromatography so as to determine trace organophosphorus residues in urea, and the magnetic metal organic framework material is relatively high in flexibility.

The invention relates to a method for macrosegregation numerical simulation of a casting, aiming at solving the problems of long computation time, low precision and unsuitability for predication of castings with large size or complex shapes in the traditional macrosegregation. The method comprises the following steps of: performing mesh generation on a selected dendritic crystal growth microcosmic computation field; computing dendritic crystal growth shapes during alloy solidification under different maximum nucleation densities from a microcosmic scale, and outputting a solid phase fraction-average dendritic crystal solid phase feature diameter curve; performing macro-scale mesh generation on the casting; computing a mass, momentum, energy and composition conservation equation from a macrocosmic scale; computing a solid phase fraction by using a Newton downhill method; and computing a pasty zone permeability model from a macrocosmic scale by adopting a linear interpolation technologybased on the solid phase fraction-average dendritic crystal solid phase feature diameter curve under a given nucleation density. The method disclosed by the invention is suitable for macrosegregationnumerical simulation in sand casting and metal mold casting of various sizes and complex shapes.

The invention relates to a method for detecting a plurality of mycotoxins in a sesame paste, and particularly relates to a method which carries out pre-treatment by an optimized dispersive solid-phase extraction method (QuEChERS), and simultaneously detects 26 mycotoxins in sesame paste by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS / MS). The method particularly comprises: extracting a sample twice with acid-containing acetonitrile-aqueous solutions with different concentrations, adding magnesium sulfate and sodium chloride into the sample extract for salting out, performing centrifugation, adding n-hexane into the obtained supernatant, performing vortex oscillation and degreasing, purifying the product with C18 and magnesium sulfate, performing vacuum concentration, dissolving the residues again with methanol and water in order to obtain a sample analytic solution, and detecting the solution by a multi-reaction monitoring mode of ultra-high performance liquid chromatography-tandem mass spectrometry. The method improves the detection efficiency, saves detection cost, is high in sensitivity, high in repeatability, and high in adding standard recovery rate, and can be extended to detection of other samples with a high grease content.

This invention concerns a method, devices, instrument and program for extraction an ingredient from a liquid sample by bidirectional transfer of an aliquot of fluid between compartments, the method can be applied to a wide variety of laboratory techniques such as; solid phase extraction by filter disc, column chromatography, magnetic separation, diagnostic tests and others, the system is suitable for single or multi sample handling, manual operation or integrated into an automated system, can be used in a lab or in field.

The invention discloses a method for simultaneously measuring multiple residues of organic chloride and pyrethroid pesticides. The method comprises the following working procedures: crushing a tobacco sample until grain diameters are less than 450 mu m; adding 10 to 20ml of extracting solution and internal standard solution into every program of tobacco sample; extracting the mixed solution by using ultrasonic wave; filtering the mixed solution by using a funnel filled with anhydrous sodium sulfate to obtain the extracting solution; adding the extracting solution into a Florisil solid extraction column for extracting and eluting; collecting an eluent; analyzing the eluent by using a gas chromatograph, wherein the analysis comprises the following conditions: adopting an Elite 5MS capillary column, high-purity N2 as a carrier gas, a constant flow mode in which the flow rate is 0.5 to 1.5 ml / min, a sample inlet temperature of between 280 and 320 DEG C, a detector temperature of between 330 and 370 DEG C, splitless sampling in which the sampling volume is between 1 and 2 mu L, and an initial temperature of 100 DEG C which rises from 100 to 180 DEG C at a speed of 8 DEG C / min, is kept for 4 minutes, rises from 180 to 270 DEG C at the speed of 5 DEG C / min and is kept for 15 minutes until all sample flows out completely; and determining the nature of the sample by using the retaining time of a standard sample and quantifying by using an internal standard method. In the method, ultrasonic wave is adopted for extracting and a solid extraction column is adopted for purifying, so that the method has the advantages of operating step simplification, high work efficiency, good purification effect, capability of simultaneously measuring multiple residues of 25 kinds of pesticides including 17 organic chloride pesticides of hexachlorocyclohexane, DDT and the like, seven pyrethroid pesticides such as fenpropathrin and the like, and one plant growth regulator.

The invention relates to a solid phase extract sampling bottle and heat analysis device in the field of sample measuring technology. It is a liquid-solid extraction and gas-solid absorption technology, which is used to pre-treat gas sample, liquid sample and isotropy sample and to extract and collect the objecting component, especially in color analysis and instrumental analysis. The solid phase extract sampling bottle and heat analysis device comprises an extract sampling bottle which is like a cylinder with one open end and one sealed end as bottom, and a casing and one layer extracting fixed phase on the middle part of the cylinder's inner wall, a heat analysis device and an extract sampling bottle cleaning device.