143 results about "Mass spectrography" patented technology

The invention relates to the technical field of nutritious food configuration, and discloses a system and a method for configuring personalized nutritious food, and the method for configuring personalized nutritious food comprises the following steps: collecting spectral characteristic data and chemical component data of a food material sample by adopting a hyperspectral imaging and mass spectrum combined technology, and obtaining holographic chemical fingerprint information; processing the collected spectral data by using a multi-scale feature extraction algorithm, extracting multi-level feature information of the food materials, and carrying out standardization and dimension reduction processing on the feature data; according to the method, high-precision prediction of the nutrient content of the food material is realized through combination of hyperspectral imaging and mass spectrometry technologies and a deep learning model, so that the nutrient content prediction accuracy and the configuration scheme accuracy are improved, the nutrient balance achievement rate is also improved, and meanwhile, the limitation of a static database is broken through; real-time nutritional ingredient analysis of any food material is achieved, the method can adapt to individual differences and freshness changes of the food materials, and accurate configuration based on actual food material characteristics is provided.

This invention discloses an AfBPP-based active molecular probe for thiostreptin, its preparation, and its application, belonging to the field of chemical biology. This invention introduces a bifunctional tag integrating a photocrosslinking group (bisacrididine) and a bioorthogonal reactive group (alkynyl group) into the structure of thiostreptin. While retaining the original biological activity of the parent compound, it endows the probe with highly efficient probe function, solving the technical problem of target loss during washing and purification of traditional non-covalent probes. After target labeling, the probe can specifically connect to reporter groups such as fluorescein or biotin through click-chemical reactions, achieving efficient enrichment of drug targets. Combined with mass spectrometry analysis, it enables global identification of potential targets in cells or complex biological samples at the omics level, such as chemical proteomics, providing a powerful molecular tool for in-depth revelation of the potential targets and pharmacological mechanisms of thiostreptin.

Methods for mass spectrometry, which include the following: Predictions of one or more first reaction products that may result from subjecting an analyte to one or more reactions of interest, Calculating one or more first masses or mass / charge ratios and one or more first ion mobility values, collision cross sections or interaction cross sections of at least some first reaction products that can be generated under first conditions using the one or more first reaction products, Calculating one or more second masses or mass / charge ratios and one or more second ion mobility values, collision cross sections or interaction cross sections of at least some second reaction products that can be generated under two different conditions using one or more first reaction products, Generating third ions from a sample and experimentally determining one or more third masses or mass / charge ratios and one or more third ion mobility values, collision cross sections or interaction cross sections of at least some of the third ions under the first conditions, Generating fourth ions from the sample and experimentally determining one or more fourth masses or mass / charge ratios and one or more fourth ion mobility values, collision cross sections or interaction cross sections of at least some of the fourth ions under the second conditions, and Comparing the first and second masses or mass / charge ratios with the third and fourth masses or mass / charge ratios and / or comparing the first and second ion mobility values, collision cross sections or interaction cross sections with the third and fourth ion mobility values, collision cross sections or interaction cross sections to confirm the presence and / or absence of one or more first reaction products in the sample.

The disclosure relates generally to compounds and methods for selective gas phase enrichment of modified peptides for reactive protein profiling.

A gas analysis apparatus and method are disclosed that can perform measurements in direct and collection modes without complex control. The gas analysis apparatus 100 according to this disclosure includes: a branching component 20 for branching a target gas; a mass spectrometer 80 for mass spectrometry analysis of one branch of the target gas; a collection component 60 for holding another branch of the target gas; a gas chromatograph 70 for analyzing the other branch of the target gas held by the collection component; and a controller 50 for controlling the flow paths of the one branch of the target gas and the other branch of the target gas. During thermal analysis, the branching component 20 is controlled to continuously branch the supplied target gas and discharge the one branch of the target gas and the other branch of the target gas, and after the thermal analysis is completed, the other branch of the target gas held by the collection component 60 is supplied to the gas chromatograph 70.

The invention relates to the technical field of biological medicine, and discloses a preparation method and application of a novel spironolactone derivative based on intestinal fungus biotransformation, and the method comprises the following steps: S1, screening an intestinal fungus Syncephalasetum monosporium as a transformation strain; s2, carrying out in-vitro fermentation culture on the screened strains; s3, extracting metabolites in the fermentation liquor; s4, identifying and separating the novel spirolactone derivative by combining mass spectrometry and a chromatographic separation technology; and S5, verifying the aldosterone receptor antagonistic activity of the derivative through molecular docking simulation. A novel spirolactone derivative is identified and separated through strain screening, fermentation condition optimization, multi-stage purification and mass spectrometry and chromatographic separation technologies, the enzyme activity of the strain is activated through shake culture in a culture medium to promote metabolism, the product purity is improved through inactivation, extraction and chromatographic purification, and the problems that a product is single and low in purity in a traditional method are solved.

Processes for quantitating the corrosivity of naphthenic acids in a sample comprising crude oil or a liquid fraction thereof by reacting the sample with a metal comprising iron to produce iron naphthenates that are then stabilized by a ligand. The stabilized iron naphthenates are then analyzed by mass spectrometry to accurately quantitate the percentage of total naphthenic acids in the sample that are iron-reactive naphthenic acids associated with metal corrosion.

The invention relates to the technical field of analytical chemistry sample pretreatment, in particular to an efficient sample injection system for improving liquid sample injection efficiency. Comprising an injection pump, an enrichment cavity, an organic filter membrane, a closed heating pipe and a capillary tube, the organic filter membrane is arranged in the enrichment cavity and divides the enrichment cavity into a chamber I and a chamber II, the injection pump injects a liquid sample into the chamber I through a first pipeline, and the liquid sample is enriched in the chamber II through the organic filter membrane; the chamber II is sequentially connected with a closed heating tube and a capillary tube through a second pipeline, an outlet of the capillary tube is connected with a time-of-flight mass spectrum, the chamber II injects purging gas through a first purging gas pipeline, an enriched sample in the chamber II is purged into the closed heating tube to be gasified and heated, and then the enriched sample is introduced into the time-of-flight mass spectrum through the capillary tube to be analyzed. The device has the characteristics of compact structure, high integration level and high enrichment and gasification efficiency, realizes efficient conversion and sample introduction from a liquid sample to gas, and remarkably improves the sensitivity and efficiency of mass spectrometry.

The application provides a construction method of Xiaoru Wan substance reference fingerprint and the fingerprint, and the construction method comprises the following steps: adopting high performance liquid chromatography combined with high resolution mass spectrometry to analyze a to-be-detected sample, and obtaining a Xiaoru Wan fingerprint. The liquid chromatography-mass spectrometry method adopted by the application is simple in operation, good in stability, high in precision, and good in reproducibility, the constructed fingerprint has rich chemical information, can make various effective components be well separated, and combined with a chromatogram of a reference solution, finally, 10 chemical components are identified, Xiaoru Wan and its pharmaceutical preparations can be effectively and comprehensively detected, the blank of the fingerprint in the quality control of the classic famous prescription Xiaoru Wan is filled, and the Xiaoru Wan and the related preparation research are provided with reference and basis.

The invention relates to the technical field of mass spectrometry, in particular to a coaxial type mass spectrum sampling device and a mass spectrum sampling method.The coaxial type mass spectrum sampling device comprises a sampling module, a crimping module and a puncture valve, the sampling module is provided with a puncture sampling cavity and a coaxial sampling cavity, and the coaxial sampling cavity is communicated with the puncture sampling cavity and externally connected with a mass spectrometer through a mass spectrum exhaust connector; a valve assembly is arranged in the coaxial sampling cavity, and a high-vacuum air exhaust channel and a micro-adjusting valve sample injection channel are formed alternately or simultaneously under the adjustment of the valve assembly. According to the invention, the high-vacuum pumping channel and the micro-regulating valve sample introduction channel are integrated in the same coaxial sampling cavity, seamless switching of two functions of vacuum pumping and micro-sample introduction is realized, the invalid volume of the sampling cavity and a connecting pipeline is obviously reduced, the dilution degree of limited sample gas released by a to-be-tested device is greatly reduced, and the sampling efficiency is improved. And the number of effective sample molecules entering a mass spectrometer in unit time is increased, so that the detection sensitivity and the signal-to-noise ratio of mass spectrometry are directly improved.

To provide a system for performing multiplexed ion pre-separation for mass spectrometry.SOLUTION: The system includes a pre-separation device for separating the precursor ions into a set of discrete fractions of precursor ions based on a physical property of the precursor ions and for sequentially transmitting a first subset of the discrete fractions of precursor ions included in the set of discrete fractions of precursor ions. The system further includes a mass spectrometer positioned downstream of the pre-separation device for receiving the first subset of the discrete fraction of precursor ions. The mass spectrometer includes an ion storage for accumulating a first population of product ions generated from each discrete fraction of precursor ions included in the first subset of discrete fractions of precursor ions and a mass analyzer for performing mass analysis of the first population of product ions.SELECTED DRAWING: Figure 1

The invention discloses a digoxin drug concentration detection method, which comprises: S1, determining a to-be-detected drug, and carrying out working curve preparation on a detection object, the to-be-detected drug being digoxin; s2, taking out the to-be-detected sample, the calibration product, the quality control product and the internal standard extraction liquid, placing at room temperature, and uniformly mixing; s3, respectively taking a to-be-detected sample, a calibration product, a quality control product and a blank sample, putting into an EP tube, adding the internal standard intermediate solution, adding methanol, uniformly mixing by vortex, and centrifuging; s4, putting the supernate into a 96-well plate, adding ultrapure water, and putting the 96-well plate on a microwell plate oscillator for shaking; and S5, centrifuging in a multi-tube rack automatic balancing centrifuge, detecting and verifying by using liquid chromatogram-tandem mass spectrum, and collecting a mass spectrum signal. According to the present invention, the high performance liquid chromatography separation and the mass spectrometry are combined, such that the complex background interference in the blood sample is overcome, the cost performance is improved, and the high sensitivity, the high accuracy and the convenient detection can be achieved for the digoxin sample with the low in-vivo concentration.

This invention relates to a pufferfish TRPV1 inhibitory peptide, its preparation method, and its application. The amino acid sequence of the peptide is LDIF. The preparation method includes: 1. Enzymatically hydrolyzing pufferfish skin, then inactivating the enzyme, and screening for peptides with a molecular weight not greater than 1 kDa from the hydrolysate, followed by freeze-drying to obtain the pufferfish skin enzymatic hydrolysate peptide; 2. Performing mass spectrometry analysis on the pufferfish skin enzymatic hydrolysate peptide, using mass spectrometry analysis software, and selecting multiple non-repeating peptide sequences based on the criteria of confidence level -10lgP > 20 and amino acid count < 10; 3. Molecularly docking the selected peptide sequences with the TRPV1 receptor using software to select peptide sequences with strong binding affinity to the TRPV1 receptor; 4. Solid-phase synthesis of the selected peptide sequences to obtain the peptide LDIF. This invention uses pufferfish skin as raw material to obtain a peptide with good inhibitory effect on TRPV1, which can be used to prepare skin care products for soothing sensitive skin.

Methods and compositions for detecting isoaspartate residues in polypeptides using mass spectrometry, and for distinguishing isoaspartate residues from aspartate and / or asparagine residues in a polypeptide using MS analysis. Polypeptides containing one or more isoaspartate residues, or suspected of containing one or more isoaspartate residues, are treated with L-isoaspartyl methyltransferase (PIMT), which is able to selectively modify isoaspartate and impart a mass change to the amino acid residue. The polypeptide is then analysed using mass spectrometry, where a mass change caused by the PIMT reaction is detected and characterized. Preferably, these methods are able to be performed without the use of liquid chromatography or other similar separation techniques prior to mass spectrometry analysis.

The invention discloses a method for detecting the impurity content of ticagrelor, the impurity is N-nitrosoticagrelor, and the detection method comprises the following steps: diluting an initial sample, and preparing to obtain a detection sample; a detection sample enters a mobile phase through a sample injector, a chromatographic column with phenyl-hexyl bonded silica gel particles as a filler is adopted to carry out gradient elution treatment on the detection sample to obtain an eluted sample, the mobile phase comprises an organic phase and a water phase, and the gradient elution conditions comprise that in the first stage, the ratio of the organic phase to the water phase is in direct proportion to the duration; in the second stage, the ratio of the organic phase to the water phase is the ratio at the end of the first stage; in the third stage, in the mobile phase, the ratio of the organic phase to the water phase is inversely proportional to the duration; a fourth stage, in the mobile phase, the ratio of the organic phase to the water phase is the ratio at the end of the third stage, and the ratio of the organic phase to the water phase in the fourth stage is smaller than the ratio of the organic phase to the water phase in the second stage; and performing mass spectrometry analysis on the eluted sample to determine the components of the eluted sample.

A quantitative analysis method and quantitative analysis device speeding detection and resistant to the effect of the condition of the device (fluctuations in sensitivity) in mass spectrometry using a mass spectrometer, i.e., a quantitative analysis method of a measured object using a mass spectrometer, which quantitative analysis method comprising a gas introduction step of mixing a gas of the measured object and a carrier gas different from the gas of the measured object and having two or more natural isotopes and introducing them to a mass spectrometer, a mass spectrometry step of mass spectrometry of the gas of the measured object and the two or more natural isotopes in the carrier gas at the mass spectrometer, and a gas concentration calculation step of calculating a concentration of the gas of the measured object using analyzed values of the two or more isotopes of the carrier gas obtained by the mass spectrometry step as calibration standards.

The invention belongs to the technical field of pesticide residue detection, and relates to a method for detecting residues of four herbicides in farmland soil through QuEChERS pretreatment-high performance liquid chromatography-tandem mass spectrometry. The method comprises the following specific steps: (1) drawing a standard curve: preparing a mixed standard solution of four pesticides including topramezone, bicyclopyrone, isoxaflutole and dicarfentrazone, carrying out high performance liquid chromatography-tandem mass spectrometry analysis, and drawing the standard curve according to the concentrations of the four pesticide standard solutions and quantitative ion pair peak areas; (2) QuEChERS pretreatment: performing solvent extraction, salt extraction and purifying agent treatment on to-be-detected soil to obtain a to-be-detected sample solution; and (3) analyzing the concentration of the pesticide residues: performing high performance liquid chromatography-tandem mass spectrometry analysis on the sample solution to be detected, and calculating to obtain the concentration of the four pesticide residues in the soil to be detected. The method is simple in pretreatment, high in detection recovery rate, good in detection result repeatability and high in detection sensitivity.

The present disclosure provides isotopic mass tags for labelling peptides and other biomolecules, as well as methods of detecting an analyte by identifying by mass spectrometry one or more of the mass labels, or combinations thereof, described herein.

This invention provides a method for detecting free fatty acids in human serum. The method comprises: adding multiple fatty acid standards and a condensing agent to a solvent to obtain a fatty acid solution with activated carboxyl groups; adding an isotopic compound to the fatty acid solution, where the carboxyl groups of the fatty acids undergo a condensation reaction with the amino groups of the isotopic compound to obtain a derivatized isotopic internal standard solution; adding the condensing agent and a non-isotopic compound of the same type as the isotopic compound to a serum sample, where the carboxyl groups of the fatty acids in the serum sample undergo a condensation reaction with the amino groups of the non-isotopic compound to obtain a reacted solution; adding the isotopic internal standard solution and sending the sample to a mass spectrometer for detection to obtain the fatty acid content in the serum sample. This invention has the advantages of low detection difficulty and high accuracy.

The application discloses a shrimp head hydrolysate with anti-freezing activity and a preparation method and application thereof, and belongs to the technical field of biology. The shrimp head is treated by fermentation with the aid of a magnetic field and Pediococcus pentosaceus, and a shrimp head hydrolysate with high anti-freezing effect is prepared. Six polypeptides with high anti-freezing activity are identified from the shrimp head hydrolysate through mass spectrometry analysis. The polypeptides have high ice recrystallization inhibition activity, can inhibit the formation of ice crystals and the migration of water during the food freezing process, reduce the mechanical damage of ice crystals to food, inhibit the protein denaturation caused by ice crystals, and can also reduce the thawing loss and cooking loss of food, and has great application value in food frozen storage.

The application relates to the technical field of analytical instruments, in particular to a mixing unit, a mixing module, a chromatographic analysis device and a method, wherein the mixing unit comprises: at least one mixing layer and at least one diffusion layer arranged in sequence along a fluid flow direction; the mixing layer comprises: at least one flow splitting structure configured to split the fluid flowing into the mixing layer into multiple flow paths; and the diffusion layer comprises: at least one special-shaped micro-flow channel configured to make the fluid flowing through the special-shaped micro-flow channel change in flow direction and / or flow rate. The mixing unit of the application first disperses a single fluid into multiple flow paths through the flow splitting structure, thereby increasing the contact area between the sample solution and the mobile phase; the fluid split by the flow splitting structure is forced to change in flow direction or flow rate by the special-shaped micro-flow channel in the diffusion layer, so that the fluid generates turbulent flow, thereby realizing molecular-level mixing of the sample solution and the mobile phase and improving the accuracy of quantitative results of chromatographic analysis and mass spectrometric analysis.

The invention relates to the technical field of food chemistry, and particularly discloses an oxidized triglyceride mass spectrum analysis method based on a thermal oxidation reaction mechanism and a mass spectrum fragmentation rule prediction spectrum library, which comprises the following steps: P1, constructing possible oxidized acyl chains based on the types of unsaturated fatty acids in common vegetable oil and oxidation mechanisms of different double bond sites of molecules of the unsaturated fatty acids, predicting the molecular structure of the oxidized triglyceride according to the acyl chain composition and the Cartesian product, and calculating the molecular formula, molecular mass and adduct ion mass of the oxidized triglyceride; p2, calculating mass spectrum collision induced dissociation core fragments according to general laws of different types of oxidized triglyceride, and constructing primary and secondary prediction spectrum libraries of oxidized triglyceride; p3, collecting sample data based on a non-targeted liquid chromatography-mass spectrometry method; p4, annotating and identifying oxidized triglyceride molecules in the vegetable oil sample; according to the method, high-throughput detection of oxidized triglyceride molecules in vegetable oil can be realized without complicated pretreatment and enrichment methods.

A system comprising pipemidic acid-1,3,4-thiadiazole hybrid derivatives with a thiadiazole group at position C-6 of the pipemidic acid skeleton, synthesized and structurally determined by IR-, 1 H-NMR-, 13 Confirmed by C-NMR and mass spectrometry.

The invention discloses a sample pretreatment method for low-molecular-weight protein in plasma, which comprises the following steps: diluting the plasma with an ammonium formate solution, loading the diluted plasma to a C18 solid-phase extraction column, sequentially carrying out gradient elution and resolution on a complex sample by using seven ACN / AmF solutions with different proportions from low to high, with the volume ratio of ACN being 15-90%, the volume ratio of AmF being 1-10%, the volume ratio of AmF being 1-10%, and the volume ratio of AmF being 1-10%. And combining subsequent reductive alkylation, enzymolysis and mass spectrometry to finally realize efficient enrichment and accurate identification of the low-molecular-weight protein in the plasma. According to the method, the experiment workload and the identification effect are balanced, the identification number and the coverage degree of the plasma low-molecular-weight protein are remarkably improved, the defects in the prior art are overcome, a more practical pretreatment means is provided for plasma proteomics research, and meanwhile due to the fact that the low-molecular-weight protein is a key biomarker resource for disease diagnosis, the application prospect is wide. The method also lays an important foundation for mining biomarkers related to diseases and assisting clinical diagnosis and medical research.

The application relates to a flame ionization device and a mass spectrometry method, which comprises a combustion chamber, an ionization assembly, an electrode and a fairing, the combustion chamber is provided with an opening and an ionization outlet, the ionization outlet is communicated with an inlet of a mass spectrometer, the ionization assembly comprises an ionization flame, the ionization flame can be combusted in the combustion chamber, the ionization flame can generate plasma, the electrode is installed in the combustion chamber and is oppositely arranged with the ionization outlet, the fairing is oppositely arranged with the opening, so that a plasma area is formed between the ionization flame and the fairing, and the plasma area ionizes and gasifies a sample to be detected. The combustion chamber and the fairing are arranged, so that the ionization flame is prevented from being affected by the environment, and a high-density plasma area is formed; the electrode is oppositely arranged with the ionization outlet, so that the plasma area is in an electric field generated by the electrode, positive and negative charge particles in the plasma move in opposite directions, neutralization is prevented, the quantity of the plasma is improved, the ionization efficiency is improved, the detection signal is more stable, and the detection result repeatability is improved.

The present invention generally pertains to methods of preventing disulfide scrambling in non-reducing liquid chromatography-mass spectrometry analysis of a protein of interest. In particular, the present invention pertains to the addition of maleimide to a non-reducing liquid chromatography-mass spectrometry analysis of a protein to prevent disulfide scrambling.

This invention relates to a method for preparing a plasma sample containing amyloid β-peptides for mass spectrometry analysis, comprising the following steps: a) contacting the plasma sample with a denaturing agent; b) performing a first solid-phase extraction step on the solution obtained in step a) to recover a first eluent; c) performing a second solid-phase extraction step on the first eluent obtained in step b) to recover a second eluent; and d) drying the second eluent obtained in step c) and processing it for mass spectrometry analysis, wherein the solution obtained in step d) contains intact amyloid β-peptides Aβ40 and Aβ42.

This invention discloses a method and apparatus for optimizing the extraction and characterizing the components of plant polyphenols, relating to the field of natural product extraction and component analysis technology. The method includes: selecting plant raw materials, drying, pulverizing, and sieving to obtain fine powder; determining the appropriate value range for ethanol concentration, material-to-liquid ratio, extraction time, and ultrasonic power through single-factor experiments, and detecting the total polyphenol content; based on this range, using response surface methodology to fit a regression model, and optimizing the extraction process parameters with the total polyphenol content as the response value; obtaining the plant polyphenol extract through ultrasonic extraction under optimal conditions; and then using UPLC-MS / MS to qualitatively and quantitatively characterize the polyphenolic components in the extract, thereby completing the entire process of efficient extraction and systematic component analysis of plant polyphenols. This invention achieves accurate qualitative and quantitative analysis of polyphenol components through high-sensitivity mass spectrometry analysis, solving the problem of insufficient data support for extract quality evaluation.

The invention belongs to the technical field of petroleum development, and relates to a heavy oil thermal recovery high and low temperature oxidation state judgment method and device and a storage medium. Carrying out dehydration operation on the crude oil sample; separating non-hydrocarbon and asphaltene mixed components in the crude oil sample; esterifying the organic fatty acid in the non-hydrocarbon and asphaltene mixed component; extracting organic fatty acid methyl ester in the crude oil sample; performing chromatography-mass spectrometry analysis on the organic fatty acid methyl ester; and judging the heavy oil thermal recovery high-low temperature oxidation state according to an analysis result. The heavy oil thermal recovery high-low temperature oxidation state judgment method and device and the storage medium have the advantages of being simple, short in period and the like, other unnecessary components are not prone to being mixed in when non-hydrocarbon and asphaltene mixed components are separated, the analysis precision is high, and the judgment result is accurate.

A toner which has a toner particle and silica fine particle A on a surface of the toner particle, wherein a weight average particle diameter of the toner is 4.0 to 15.0 μm, a carbon loss ratio when the silica fine particle A is washed with hexane is 5 to 70%, and a temperature at which a differential coefficient of a nine-point moving average of integrated values integrated from 35° C. reaches 4000 or more for an intensity of an obtained ion having a mass number (M / z) of 207 is 270° C. or higher, when mass spectrometry is carried out at a sampling interval of 0.4 seconds while heating the silica fine particle A under specific conditions.