224 results about "Isotopic labeling" patented technology

The invention discloses a river nitrogen pollutant source analysis method based on drainage basin nitrogen turnover and isotope, and particularly relates to the technical field of water treatment.The river nitrogen pollutant source analysis method comprises the following steps that a drainage basin to be researched is selected, river water and soil samples in the drainage basin are systematically collected, and physical and chemical indexes and isotope indexes # imgabs0 # of the collected samples are tested. Nitrate marked by nitrogen isotope delta 15N / delta 18O and # imgabs1 # are used as key indication marks to perform high-precision identification on nitrogen sources in a river and an environmental system, the contribution proportion of different nitrogen sources to the nitrate concentration in a water body is quantified through a stable isotope analysis model, and the concentration of the nitrate in the water body is calculated. And in combination with data, the rates of denitrification and anaerobic ammonia oxidation in environmental samples, sediments and soil are directly measured through combined application of an isotopic tracer technology and a membrane inlet mass spectrometer technology.

The invention relates to the technical field of dynamic tracking, in particular to a human dance dynamic tracking method and system, and the method comprises the following steps: selecting a target stable isotope as a marker according to atomic weight and chemical properties, mixing the target stable isotope with a proper amount of carrier, and smearing the mixture on key joints and muscle groups of a dancer to generate a key marker combination. According to the invention, through cooperation with specially developed isotope labeling detection equipment, the identification effect under various illumination and background conditions is optimized, the data accuracy and tracking continuity are ensured, and the accurate three-dimensional motion model is constructed, so that the real-time reaction speed and the motion response precision of the model are improved; in addition, key action nodes are allowed to be extracted from the model and used for dynamically tracking and evaluating the coherence of the actions, through deep action analysis, the dancer and the coach can obtain detailed technical evaluation and improvement guidance, and the quality of dance performance and the technical level of the dancer are effectively improved.

The invention provides a 13C and 15N stable isotope labeled polypeptide abundance determination method based on a high-resolution mass spectrum, and belongs to the technical field of high-resolution mass spectrum determination. The determination method comprises the following steps: selecting a certified standard substance to calculate the system deviation delta 1 of the high-resolution mass spectrometer; calculating a theoretical relative deviation delta 2 of 13C and 15N isotopes in the 13C and 15N stable isotope labeled polypeptide according to a formula 2; collecting and recording a mass spectrum signal of a to-be-measured sample, and calculating to obtain an actual measurement relative deviation delta 3 of the to-be-measured sample; and when delta2 > delta3 > delta1, calculating the abundance value of the corresponding isotope label according to a formula 3 and a formula 4. According to the method disclosed by the invention, the flow injection sample is directly detected by adopting the high-resolution mass spectrometry, so that the detection speed is high, the high resolution is ensured, and the detection time is saved; only the response intensity and the m / z value of a target ion peak are needed for the analysis of a mass spectrum, and the operation is simple and convenient.

The invention discloses a compound derivative represented by a formula I or an isotope labeled compound thereof, or an optical isomer, a geometric isomer, a tautomer or an isomer mixture thereof, or a pharmaceutically acceptable salt thereof. According to the application of a double protection strategy, diversified carrier fragments are introduced to 5-hydroxyl and hydroxylamine in N4-hydroxycytidine molecules, the N4-hydroxycytidine prodrug is invented, the affinity of lung cell membranes (phospholipid membranes) is improved, and the physicochemical properties of the drug are made to meet the requirements of the physiological environment of lung tissue. Therefore, the compound disclosed by the invention has a wide application prospect in the aspect of broad-spectrum respiratory virus resistance. # imgabs0 #

The invention discloses a method for extracting a p-phenylenediamine antioxidant in a liquid sample and application of the p-phenylenediamine antioxidant. The p-phenylenediamine antioxidant comprises N-(1, 2, 4-trimethyl-1, 3-pentanediol) the organic solvent is at least one of N, N '-diphenyl-1, 3-dimethyl butyl)-N'-phenyl p-phenylenediamine, N-cyclohexyl-N '-phenyl p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine, N, N '-diphenyl-1, 4-phenylenediamine, N, N'-di-2-naphthyl p-phenylenediamine and 2-((4-methylpentane-2-yl) amino)-5-(phenyl amino) cyclohex-2, 5-diene-1, 4-diketone. According to the method, liquid-liquid extraction which is simple and efficient to operate, low in cost and good in repeatability is adopted as a sample pretreatment method, and is combined with an isotope label method and an ultra-high performance liquid chromatography-tandem mass spectrometry technology, so that separation and qualitative and quantitative detection of six p-phenylenediamine antioxidants and quinone derivatives in a sample are realized; meanwhile, the sensitivity is high, the quantity of isotope internal standards is small, the solvent loss is small, and the actual detection requirement is met.

The invention discloses a soil microorganism carbon utilization efficiency determination method, and relates to the technical field of carbon utilization efficiency determination, and the method comprises soil sample pre-culture, multi-source 18O isotope gradient labeling, dynamic gas monitoring, microorganism respiration rate dynamic correction, and microorganism growth rate and carbon utilization efficiency acquisition. By labeling multi-source isotopes and quantifying contributions of different oxygen sources to microorganism DNA synthesis, underestimation of the carbon utilization efficiency caused by a traditional single labeling method is avoided, the problem of limitation existing in the current soil microorganism carbon utilization efficiency determination process is solved, the inhibition effect of too high local concentration on microorganism metabolism is reduced through gradient labeling, and the accuracy of soil microorganism carbon utilization efficiency determination is improved. The method has the advantages that marking uniformity is improved, multiple groups of soil samples are arranged, real-time change of microbial respiration is captured by means of dynamic monitoring, influence of isotope fractionation on carbon dioxide concentration calculation is eliminated, instantaneous errors of traditional static measurement are avoided, and accuracy of analysis results is improved to a certain extent.

The invention relates to preparation and application of a novel trifluoroalkyl sulfur-containing phenyl heterocyclic ring derivative. Specifically, the invention relates to a compound as shown in formula (I) containing a trifluoroalkyl thiophenyl heterocyclic derivative, an isotope labeled compound of the compound, an optical isomer, a geometric isomer, a tautomer or an isomer mixture of the compound, or a pharmaceutically acceptable salt of the compound, and application of the compound in preparation of insecticides for pest control. The compound can achieve a better pest control effect at a lower dosage, especially for pests and pest mites such as tetranychus cinnabarinus, tetranychus urticae and panonychus citri.

The invention discloses a soil-plant carbon element tracking method and system based on isotope labeling, particularly relates to the technical field of soil carbon cycle in-situ detection, and is used for solving the technical problem that a carbon migration path in a rice rhizosphere heterogeneous micro region cannot be distinguished in the prior art. The method comprises the following steps: arranging a spatial coding microprobe array on a rice root system and a soil interface of a rice field, synchronously applying a C13 labeled compound, and continuously obtaining a grid node oxidation-reduction potential and a carbon isotope abundance value; dividing the boundary of a root surface oxidation layer and an anaerobic layer based on day and night oscillation phase difference mutation; detecting peak displacement migration from carbonyl bonds to carbon-carbon bonds in a boundary transition region by adopting an in-situ Raman spectrum, and correcting a space boundary; partitioning and clustering carbon isotope abundance values according to the corrected boundary, and identifying hot spot boundaries of a root tip secretion active region, a microorganism enrichment region and a mineral binding region; calculating the carbon isotope flux gradient in each region and generating a spatial distribution map; in-situ analysis of a rhizosphere carbon migration path is realized, and rice field carbon cycle research precision is improved.

The present invention relates to a pyrazine derivative, an application thereof in inhibiting SHP2, and a compound of formula (I) or pharmaceutically acceptable salts, esters, isomers, solvates, prodrugs or isotope labels thereof. The structure of the compound of formula (I) is as follows. The novel pyrazine derivative provided by the present invention has excellent inhibition of SHP2 activity and can be used to prevent and / or treat non-receptor protein tyrosine phosphatase-mediated or dependent diseases or disorders.

The invention provides an electroactive biofilm for degrading enriched sulfonamide antibiotics and a method for identifying microorganisms, and relates to the technical field of environmental microorganisms and wastewater treatment. The method for degrading the electroactive biological membrane by enriching the sulfonamide antibiotics and identifying the microorganisms comprises two steps of directional enrichment of the electroactive biological membrane and identification and analysis of functional microbial communities, the directional enrichment of the electroactive biological membrane is carried out in a double-chamber bioelectrocatalysis system and comprises a single carbon source stage, a common carbon source stage, a single carbon source stage and a common carbon source stage, and the directional enrichment of the electroactive biological membrane is carried out in a double-chamber bioelectrocatalysis system. An isotope labeling stage; the sodium acetate in the single carbon source stage is the only carbon source; sodium acetate and sulfonamide antibiotics are used as a common carbon source in the carbon source sharing stage; in the isotope labeling stage, 13C-labeled antibiotics are used for replacing common antibiotics. According to the method, the effects of efficiently and directionally enriching, accurately identifying active degrading microorganisms and analyzing degrading genes and metabolic pathways are achieved, and technical support is provided for developing efficient degrading bacteria and bioremediation methods.

The invention belongs to the technical field of analysis and testing, and discloses an MALDI (matrix-assisted laser desorption ionization) mass spectrum imaging probe for quantifying amino acid and a method for quantifying the amino acid. The probe is simple to synthesize and can quickly and efficiently react with an amino compound, and a product is stable and strong in ionization. The detection method comprises the steps of probe characterization, standard curve making and Q-MSI strategy, and absolute quantification of amino acid is realized by adopting an isotope labeling internal standard method and combining MALDI mass spectrum imaging. According to the method, parameters such as probe spraying, incubation and matrix spraying are optimized, so that the problem that spatial distribution information is lost in tissue homogenization in the prior art is solved, spatial distribution and content difference information of amino acid can be obtained, the sensitivity is improved by several times compared with that of self-detection of amino acid, and the method has good linearity and practicability and is suitable for popularization and application. The quantitative mass spectrum imaging strategy can also be popularized and used for quantitative analysis of other endogenous compounds.

The invention discloses a kit and a method for detecting pepsin based on polypeptide, and belongs to the technical field of proteomics. The amino acid sequence of the polypeptide is as shown in SEQ ID No. 1. The polypeptide is obtained based on enzymolysis of pepsinogen PGA4 and screening, the polypeptide and isotope labeled polypeptide are utilized to establish a standard curve, a biological sample is further subjected to enzymolysis to obtain a peptide fragment sample, and pepsin in the biological sample can be quantified by detecting the content of the polypeptide in the peptide fragment sample. By utilizing the method disclosed by the invention, the pepsin in the biological sample can be rapidly quantified, so that pathological reflux and physiological reflux are diagnosed and distinguished, and the accuracy rate is high.

The invention relates to the technical field of molecular probes, and particularly discloses a molecular probe of a targeted tyrosine kinase receptor as well as a preparation method and application of the molecular probe, the molecular probe comprises radioisotope, targeted polypeptide and a chelating group, the targeted polypeptide specifically targets the tyrosine kinase receptor, the chelating group is connected with the targeted polypeptide to form a targeted precursor, and the chelating group is connected with the targeted polypeptide to form the targeted precursor. The radioactive isotope labeled precursor forms a molecular probe, and the sequence of the targeted polypeptide is shown as any one of SEQ ID No.1-8. The targeting polypeptide has good targeting property on a tyrosine kinase receptor coded by an RET gene, can realize specific high uptake in a cell line of NEPC, has relatively good biological safety, can realize accurate imaging aiming at NEPC, and clearly and durably visualizes NEPC tumors in PET imaging; meanwhile, the molecular probe can effectively delay the growth capacity of NEPC, can provide a new treatment choice for NEPC patients, and has good clinical transformation potential.

The invention discloses a method for valuing a human angiotensin II purity standard substance. The method comprises the following steps: (1) selecting human angiotensin II with the purity of more than or equal to 99% as the purity standard substance; (2) determining the value of the human angiotensin II purity standard substance by adopting a mass balance method; (3) hydrolyzing the human angiotensin II purity standard substance, taking isotope labeled phenylalanine, isoleucine and valine as internal standards, and determining the value of the human angiotensin II purity standard substance by liquid chromatography-isotope dilution mass spectrometry; and (4) calculating the average value of the fixed value results of the mass balance method and the isotope dilution mass spectrometry to obtain the fixed value result of the human angiotensin II purity standard substance. According to the method for determining the value of the human angiotensin II purity standard substance provided by the invention, the value of the human angiotensin II purity standard substance is determined by adopting a mass balance method and a liquid chromatography-isotope dilution mass spectrometry, and the finally obtained value determination result of the Ang II purity standard substance is 0.8734 g / g, so that the method has traceability.

The invention relates to a substituted arylthio thiazolidone derivative as well as preparation and application thereof. Specifically, the invention relates to a compound as shown in a formula (I), or an isotope-labeled compound, or an optical isomer, a geometric isomer, a tautomer or an isomer mixture, or an acceptable salt of the compound, which is used as a substituted arylthio thiazolidone derivative, and application of the compound in preparation of insecticides for pest control, the compound can achieve a better pest control effect at a lower dosage, especially for pests such as tetranychidae, microcosaridae, acaridae, tarsonidae, aleuridae and root-knot nematode, and can be used for controlling pests such as tetranychidae, microcosaridae, gall mite, tarsonidae, aleuridae and the like.

The invention designs a quantitative analysis method for evaluating the excitation effect of biochar on soil endogenous organic carbon, and the method combines a benzene polyacid molecular marker method and soil particle density grading to distinguish and quantify biochar and soil endogenous carbon. On the basis, a quantitative evaluation method for the excitation effect of biochar addition on the endogenous carbon in the soil is constructed, biochar information can be accurately recognized and quantified from the soil through the method, and the mineralization amount or accumulation amount of nSOC can be quantified. Specifically, according to the method, the biochar and the soil endogenous carbon are distinguished, and the time and economic cost caused by isotope labeling and CO2 detection is avoided.

The invention relates to the technical field of agricultural environmental protection, in particular to a carbon sequestration and emission reduction rice field straw returning method, which comprises the following steps: performing multistage crushing pretreatment on straws, mixing with red mud, performing gradient pyrolysis to prepare magnetic biochar, fixing specific strains, returning to the field, constructing a three-layer stubble burying structure to improve soil, and performing sensor monitoring and neural network regulation. And carbon sequestration emission reduction and intelligent management are realized, and the carbon flow direction can be tracked and a carbon sink voucher can be generated. According to the invention, through straw pretreatment, biochar preparation and fungus-carbon coupling returning, efficient carbon sequestration and emission reduction can be realized; the three-layer stubble burying structure is matched with humic acid, so that the soil structure is improved, the air permeability and water and fertilizer retention performance are improved, and crop growth is facilitated; by means of sensor monitoring and neural network regulation and control, precise management is achieved, carbon metering is conducted by combining isotope labeling with the block chain, data are accurate and safe, and powerful support is provided for carbon transactions and the like.

The present invention discloses a method for synchronously extracting and detecting 59 endocrine disruptors in amniotic fluid, belonging to the technical field of substance detection. The method includes the following steps: S1, adding β-glucuronidase to the amniotic fluid sample and incubating; S2, adding a stable isotope-labeled internal standard to the amniotic fluid sample to be detected in step S1; S3, adding the amniotic fluid sample to be detected in step S2 to an activated HLB extraction column to remove impurities and extract the target analyte; S4, eluting the extraction column to obtain an eluate, blowing it to near dryness, and adding a reconstitution solvent to obtain a sample to be detected; S5, using a liquid chromatography-mass spectrometry instrument to detect the sample to be detected obtained in step S4 to complete the detection and analysis of endocrine disruptors. The detection process is carried out simultaneously in positive ion mode and negative ion mode. This method realizes the synchronous extraction, detection and analysis of at least 59 typical environmental endocrine disruptors in amniotic fluid, which is simple and convenient, and solves the problems of large sample consumption and long time consumption.

Method for isotopic identification, allowing, where appropriate, a liquid to be linked to a site of growth or harvest or a sub-product derived from a determined liquid, via analysis of concentration or of ratios of stable isotopes, and comparison to isotopic codes generated beforehand in a manner unique to a set of liquids issued from a site of growth, harvest or conversion. The invention also relates to a method that makes it possible to give a unique code to liquids of a site of growth, harvest or conversion, and to a computer making it possible to store the unique codes generated in memory, to generate unique codes for new liquids of a site of growth, harvest or conversion and to perform comparisons.

This invention relates to a method for quantifying mRNA capping efficiency, the method comprising mixing a sample, an enzyme mixture, and an isotope standard solution in a buffer solution to produce an incubation mixture, the enzyme mixture comprising a nonspecific single-stranded nuclease and an acid phosphatase, and the isotope standard comprising isotopically labeled m7G and isotopically labeled 2'-O-methylated nucleoside; incubating the mixture; and analyzing the mixture using liquid chromatography-mass spectrometry to determine at least one of capping efficiency and 2-O-methyltransferase efficiency.

The invention discloses a device and a method for testing a steam oxidation mass transfer mechanism of a metal material. The device comprises a reaction chamber, and a sample holder is arranged in the reaction chamber; the gas inlet end of the reaction chamber is simultaneously connected with an 18O2 storage piece, an inert gas storage piece, an H216O storage piece and a D218O storage piece; a first heating assembly is arranged outside the reaction chamber, a second heating assembly is arranged outside the H216O storage part, and a third heating assembly is arranged outside the D218O storage part. According to the method disclosed by the invention, an invisible ion diffusion path is converted into a detectable signal gradient through isotope labeling, and experimental verification of an oxygen ion / metal cation diffusion dominant mechanism, visual proving of a hydroxyl participation oxidation process and quantitative analysis of a dissolved oxygen effect are realized for the first time; and a direct experimental criterion is provided for optimization of the oxidation resistance of the metal material.

The present invention discloses a method for synchronous detection of perfluorinated and polyfluoroalkyl substances in urine. It relates to the technical field of pollutant detection. The above-mentioned method for synchronous detection of perfluorinated and polyfluoroalkyl substances in urine is characterized in that it comprises the following steps: sample pretreatment: S1 adding a stable isotope-labeled internal standard compound to the urine sample to be tested; S2 adding an extractant to the sample of step S1 to extract the target analyte in the sample; S3 repeating step S2 1-3 times, and obtaining the sample to be tested after re-dissolving; detection of the sample to be tested: using ultra-high performance liquid chromatography-tandem mass spectrometry to detect the sample to be tested, so as to analyze at least 40 perfluorinated and polyfluoroalkyl substances in urine. The present invention realizes the synchronous extraction and analysis of at least 40 new and traditional PFASs in urine by improving the sample pretreatment and instrumental analysis methods, which is simple and convenient and saves solvents.

This invention discloses a method for the synergistic metabolic analysis of multiple components of traditional Chinese medicine (TCM) integrated with the gut microbiota. After initializing the microbiota ecosystem, a solution of multi-component TCM extracts is continuously injected into a microfluidic chip. Stable isotope-labeled precursors are pulsed into a specific simulation region to perform spatial isotope encoding. A standing wave acoustic field is applied at the sampling node of the microfluidic chip, and multiphase fluid spatial splitting is performed using the difference in the primary acoustic radiation force experienced by the particles to derive cell-free TCM metabolites. The cell-free TCM metabolites are separated by chromatography and gas phase drift separation. A four-dimensional metabolic feature array is constructed, and the absolute value of the mass shift is calculated for spatial inverse decoding. Closed-loop feedback is triggered based on the rate of change of target metabolite ion abundance, increasing the amplitude of the standing wave acoustic field pressure to confine intestinal bacteria and performing in-situ enrichment of synergistic metabolic intermediates. This invention realizes the spatial metabolic trajectory tracing and network reconstruction of multiple components of TCM in a complex gut microbiota ecosystem.

The invention relates to a method for simultaneously detecting polymyxin B and polymyxin E. The method comprises the following steps: (1) taking isotope labeled polymyxin B1, B2, E1 and E2 as internal standards, dissolving, and diluting with methanol containing formic acid to prepare a sample releasing agent; and (2) mixing a detection sample with the sample releasing agent, carrying out vortex, standing and centrifugation, taking a supernatant, carrying out sample introduction, and carrying out detection by adopting a liquid chromatography-tandem mass spectrometry method. The method can be used for synchronously detecting the patient sample containing the polymyxin B and the polymyxin E.

The invention relates to the technical field of chromatographic detection, in particular to a detection method for simultaneously detecting glutamic acid, citric acid and beta-citrylglutamic acid, and the detection method comprises the following steps: adding an internal standard solution into plasma to be detected, mixing, and carrying out pretreatment to obtain a solution of a product to be detected; carrying out series detection on the solution of the product to be detected by adopting an ultra-high performance liquid chromatograph-triple quadrupole tandem mass spectrometer to obtain the contents of glutamic acid, citric acid and beta-citryl glutamic acid in the solution of the product to be detected, wherein the internal standard solution comprises isotope markers of glutamic acid, citric acid and beta-citryl glutamic acid. According to the detection method, glutamic acid, citric acid and beta-citryl glutamic acid can be accurately measured at the same time, the detection efficiency is high, and the sensitivity and the specificity are high.

Provided in the present application is a compound as represented by formula (0), or a stereoisomer thereof, or a tautomer thereof, or a geometric isomer thereof, or an enantiomer thereof, or a diastereomer thereof, or a racemate thereof, or a polymorph thereof, or a solvate thereof, or a hydrate thereof, or an N-oxide thereof, or an isotope-labelled compound thereof, or a metabolite thereof, or an ester thereof, or a prodrug thereof, or a pharmaceutically acceptable salt thereof:

Various methods and compositions of treating 4-hydroxyphenylpyruvate dioxygenase-like (HPDL)-related diseases or disorders are presented herein. Also presented herein are methods of increasing CoQ10 biosynthesis, and methods of determining whether a subject will benefit from a CoQ10 or CoQ10 alternative treatment. Also presented herein are pharmaceutical compositions and dosage forms comprising 4-hydroxymandelic acid (4-HMA), and / or its metabolites. Further presented herein are compounds that inhibit 4-hydroxyphenylpyruvate dioxygenase-like (HPDL). Further presented herein are methods of identifying and / or assessing modulators of HPDL. Yet further presented herein are example methods and systems for isotopic labelling in cells by metabolizing cells in the presence of gaseous isotopic tracer.

The present invention relates to a compound of formula Xm-(Y-L-T) n and a method for the detection or prognosis of a disease in exhaled breath of a subject. X, in the presence, is a moiety operable to target the compound to a target site in vivo; m is 0 or at least 1, Y is a breakable group; l is a self-sacrifice linker, T is a capping portion, and n is 1 when m is 0 or n is at least 1 when m is at least 1, L is a self-sacrifice linker. The capping moiety T may include an isotopically labeled reporter molecule or a precursor thereof. The reporter molecule is operable to be released upon cleavage of the cleavable group Y; and the reporter molecule is a volatile compound upon release. # imgabs0 #

The present application belongs to the technical field of analysis and identification of fermented food, and particularly relates to a method for distinguishing and identifying fermented food of different processes based on chemical isotope labeling liquid chromatography-mass spectrometry (CIL-LC-MS) technology analysis of carboxylic acid. In order to accurately and simply identify the type and content of carboxylic acid, and thus based on carboxylic acid panorama analysis, efficiently and conveniently distinguish and identify fermented food of different processes, the present application introduces CIL-LC-MS technology to analyze carboxylic acid and thus distinguish and identify fermented food of different processes. The technology can significantly enhance the response value and detection sensitivity of carboxylic acid through chemical labeling strategy, and effectively overcome the ion suppression interference of the matrix by using isotope internal standard, so as to realize accurate quantification. Combined with its inherent three-level identification process, the present application can efficiently and conveniently distinguish and identify fermented food of different processes.

The invention relates to a carbon 13 isotope labeling internal standard substance of PMMA (polymethyl methacrylate) and metabolite thereof. The invention further provides a corresponding preparation method and application. The invention fills the technical blank of PMMA / PMA exclusive isotope internal standard, promotes the mental active substance detection to develop towards the direction of higher sensitivity, lower error and stronger judicial credibility through the precise design and application of the carbon 13 labeled standard substance, and has great social value for public safety and health management.