241 results about "Mass spectrography" patented technology

Provided herein are methods for analyzing a biological sample that include contacting the biological sample with a non-conductive substrate; and contacting a matrix to a surface of the biological sample. Further methods optionally include performing mass spectrometry analysis; determining presence of a first analyte in the biological sample; and / or analyzing a second analyte on the surface of the biological sample to determine presence of the first and the second analyte in the biological sample.

The invention provides a rapid quantitative analysis method for an outer vesicle proteome, and belongs to the technical field of quantitative analysis of the outer vesicle proteome. According to the rapid quantitative analysis method for the outer vesicle proteome, firstly, a high-quality outer vesicle sample is obtained through low-speed centrifugation, ultra-speed centrifugation and membrane filtration; and obtaining proteome data by utilizing two-dimensional electrophoresis and mass spectrometry. Then, a mathematical model equation set is constructed for preliminary analysis, a protein interaction network is optimized through an embedded game optimization index model, and feature extraction and quantitative analysis are conducted through a convolution parameter adaptive function and a residual network deep learning model; finally, a quantitative analysis result containing the protein expression level and the function importance is generated in combination with the multi-dimensional protein expression contribution index, and the technical problem that in the prior art, in the rapid quantitative analysis process of the outer vesicle proteome, the protein component complexity is high, and consequently the quantitative precision is low is solved.

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.

The invention discloses a white spirit flavor recognition method based on machine learning, and belongs to the technical field of food detection and artificial intelligence. Aiming at the problems of high subjectivity of manual evaluation, low efficiency of mass spectrometry, noise sensitivity of a machine learning model and the like in the prior art, the method provides a solution integrating solvent background deduction and feature weight screening. The method specifically comprises the following steps: diluting a white spirit sample with methanol according to a volume ratio of 1: 10, collecting mass spectrum data through GC-MS, and dynamically deducting a methanol background peak; a BP neural network (GABP) optimized by a genetic algorithm is utilized to automatically analyze a weight coefficient of each molecular peak to flavor classification, and key features are screened; a classification model is constructed based on XGBoost, and parameters are optimized through cross validation, so that automatic judgment of the flavor type, authenticity and quality of the white spirit is realized. According to the method, through data dimension reduction and model collaborative optimization, the overfitting problem caused by high noise and high redundancy of mass spectrum data is solved, the classification accuracy is remarkably improved, and the method can be extensively applied to white spirit brand identification, process optimization and market quality supervision.

The invention belongs to the technical field of textile organic matter detection, and relates to a PTR-MS-based rapid mass spectrometry system and method for volatile organic compounds in textiles. Through the synergistic effect of the temperature-adjustable constant-temperature heater, the optimally designed gas exchange chamber and the mass flow controller, the limitation of complex background interference and a single temperature mode is effectively solved; the temperature-adjustable constant-temperature heater can gradually adjust the temperature according to the boiling point characteristics of VOCs, the release efficiency of substances with different boiling points is optimized, interference caused by too fast release of substances with low boiling points is avoided, and therefore the detection accuracy is improved; the optimally designed gas exchange chamber is used for clamping a textile sample through two semi-spindle-shaped cavities to form a closed space, so that the contact area and time of the sample and carrier gas are effectively controlled, the interference of environmental pollutants is reduced, and the detection sensitivity is improved; and meanwhile, the mass flow controller accurately controls the flow velocity of the carrier gas, so that VOCs are fully carried into a mass spectrum acquisition instrument, and detection errors caused by improper flow velocity of the carrier gas are avoided.

Methods and systems for multi-beam, parallel-beam, deterministic, or super mass spectrometry that include an ion source that produces ions, and two or more ion trapping devices or mass spectrometers, each having an independent sampling inlet. The two or more ion trapping devices or mass spectrometers receive the ions from the ion source via the sampling inlet of each of the ion trapping devices or mass spectrometers such that each sampling inlet provides an ion beam to each corresponding ion trapping device or mass spectrometer.

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.

The invention relates to the technical field of floridoside and an isomer monomer thereof, and discloses a method for preparing high-purity floridoside and an isomer monomer thereof on a large scale, which is used for carrying out large-scale preparation and purification research on the high-purity floridoside and the isomer monomer thereof and preparing the floridoside and the isomer monomer thereof from a porphyra haitanensis crude extract. And the structure and purity of the compound are identified. The method comprises the following steps: firstly, by utilizing a DART-MS technology, through a single factor experiment, optimizing experiment parameters such as extraction times and elution, and obtaining optimal extraction efficiency; and secondly, based on a two-step purification method of a prep-HPLC (Prep-High Performance Liquid Chromatography) technology, enriching the target compound by using a reversed-phase (C18) mode stationary phase in the first step, and separating the pair of isomers by using a normal-phase (NH3) mode stationary phase in the second step. The obtained floridoside and isomer monomers thereof are subjected to structure and purity identification by mass spectrometry (MS) and nuclear magnetism (NMR). Results are as follows: the two compounds are identified as floridoside and isomers thereof through high-resolution mass spectrometry, and the purities of the floridoside and the isomers thereof are up to 99.5% or above.

A data-dependent analysis (DDA) mass spectrometry technique involves ionizing a sample to generate sample ions, analyzing the sample ions by performing one or more MS1 mass analysis scans to obtain MS1 ​​data, identifying one or more precursor ions from the MS1 data, and subsequently analyzing the sample ions by performing one or more MS2 mass analysis scans. Each MS2 scan targets one of the one or more precursor ions identified from the MS1 data.The procedure further includes, for each of the one or more precursor ions identified from the MS1 data: determining a value from the MS1 data that is indicative of a collision cross section (CCS) of that precursor ion; and selecting, based on the CCS-indicative value(s), which precursor ion(s) the one or more MS2 bulk analysis scans should target, and / or determining, based on the CCS-indicative value(s), an order in which the one or more MS2 bulk analysis scans should target the precursor ions.

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 application discloses an analysis method of non-volatile organic acids in electronic cigarette liquid, comprising the following steps: adding a to-be-tested sample of electronic cigarette liquid into an internal standard stock solution and a formic acid-methanol aqueous solution, sealing and oscillating, diluting with an internal standard solution to obtain a to-be-tested sample solution; mixing single standard stock solutions prepared by different target standard samples, diluting into a mixed standard intermediate solution, taking different volumes of the mixed standard intermediate solution, adding an internal standard stock solution and a formic acid-methanol aqueous solution, and configuring into standard working solutions with different concentrations; respectively performing ultra-high performance liquid chromatography-tandem mass spectrometry analysis on the to-be-tested sample solution and the standard working solution; and according to the analysis result, the content of the target in the to-be-tested sample is calculated by using an internal standard standard curve method. The application can realize simultaneous analysis and chromatographic separation of six non-volatile organic acids in electronic cigarette liquid, has the advantages of accurate quantification, high flux, good separation degree, simple operation, high sensitivity, good recovery rate and good repeatability, etc.

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 present invention relates to the field of component detection technology, and in particular to a method for detecting benzethonium chloride in food using ultra-high performance liquid chromatography-tandem mass spectrometry. The method comprises the following steps: extracting a food sample from the food to be tested, and pre-treating the food sample using liquid-liquid extraction and solid-phase extraction methods to obtain a pre-treated liquid sample; concentrating and dissolving the pre-treated liquid sample to obtain a sample mixed solution; performing mass spectrometry analysis on the sample mixed solution using ultra-high performance liquid chromatography-tandem mass spectrometry to obtain state information of characteristic ion signals of benzethonium chloride; obtaining an estimated concentration of benzethonium chloride based on the state information of the characteristic ion signals of benzethonium chloride; and obtaining a final benzethonium chloride concentration by introducing a dynamic ion response model and combining a recursive optimization algorithm. The method solves the technical problem that the traditional method for detecting harmful substances in food has low detection accuracy and poor sensitivity for benzethonium chloride components in food testing.

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.

The present invention relates to a method for preparing a sample for liquid chromatography and mass spectrometry, and the use of hydrophilic surface magnetic beads for preparing a sample for liquid chromatography and mass spectrometry. The method includes contacting hydrophilic surface magnetic beads and a precipitant with a sample to form precipitate-magnetic bead aggregates, and applying a magnetic field to remove the precipitate-magnetic bead aggregates. This sample processing method can be used for preparing or pretreating samples for mass spectrometry or liquid chromatography, particularly liquid chromatography-tandem mass spectrometry.

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.

In one aspect, a method of performing mass spectrometry is disclosed, which comprises ionizing a plurality of oligonucleotides to generate a plurality of negatively charged oligonucleotide ions, and interacting a plurality of charged reagent ions with the negatively charged oligonucleotide ions to reduce the negative charge state of the negatively charged oligonucleotide ions.

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.

To provide an analysis method for estimating the chemical structure of a compound with which the structure of the C=C position on a carbon chain can be estimated even for a cyclic compound.SOLUTION: An analysis method for estimating the chemical structure of a compound includes: a) a pre-processing step of performing pre-processing on a target compound so that a cyclic compound has a linear shape; and b) a mass spectrometry step of irradiating ions of the compound after the pre-processing, with at least one selected from radicals having oxidizing ability, radicals having reducing ability, and ozone to dissociate the ions, and performing mass analysis of fragment ions generated thereby to collect mass information of the fragment ions, wherein information on the ions estimated in a specific fragment ion estimation step is used for estimating the structure of the compound.SELECTED DRAWING: Figure 1