34 results about "Daughter Ion" patented technology

The invention discloses a method for detecting natural plant hormones and exogenous growth regulators of vegetables, efficient separation and accurate detection of the natural plant hormones and the exogenous growth regulators are realized through combination of hydrophilic interaction chromatography and mass spectrometry, a hydrophilic interaction chromatographic column is adopted, and conditions such as mobile phase composition and flow velocity are optimized; the selectivity of polar substances is improved by utilizing hydrophilic interaction, so that compounds with similar structures achieve baseline separation, and chromatographic peak overlapping interference is avoided; the mass spectrometric detection only responds to a specific ion signal by screening characteristic parent ion / daughter ion pairs of a target object, so that matrix impurities and non-target ion interference are effectively eliminated, the false positive risk is remarkably reduced, and the detection sensitivity and specificity are improved; the combined technology is combined with the efficient separation capacity of the hydrophilic interaction chromatographic column and a multi-reaction monitoring mode, synchronous separation of multiple compounds with similar polarities in single analysis is achieved, parallel detection of dozens of target objects is supported, and the analysis time is greatly shortened.

This invention discloses a method for determining the content and simultaneously identifying the source of polyglutamic acid (PCA) in fertilizers based on microwave digestion-high-resolution liquid chromatography-mass spectrometry (LC-MS), belonging to the field of analytical detection technology. The method includes: microwave-assisted acid hydrolysis of fertilizer samples to obtain a hydrolysate; injecting the hydrolysate into a liquid chromatography-high-resolution mass spectrometry (LC-MS) instrument, performing a single injection analysis in data-independent acquisition (DIA) mode, and simultaneously acquiring a mass spectrometry dataset containing a full-scan fingerprint of the parent ion and fragment information of the daughter ion by alternating between low and high collision energies; extracting the precise mass number of PCA from the dataset for accurate quantification, and calculating the PCA content using the difference method; simultaneously retrieving the total ion chromatogram and inferring the source of PCA based on the response of other amino acids. This invention is the first to introduce microwave digestion pretreatment and high-resolution mass spectrometry DIA acquisition mode into the field of PCA detection in fertilizers, requiring only a single injection to simultaneously complete accurate quantification and source identification, effectively avoiding false positives caused by background of plant and animal protein hydrolysates, and significantly improving the efficiency and confidence of PCA detection in complex matrix fertilizers.

The invention relates to the technical field of mass spectrum detection, particularly discloses a mass spectrum ionization source for detecting volatile substances in combination with radio frequency discharge, and solves the problems of tedious sample pretreatment steps, long analysis period, high instrument cost and the like when a traditional ion source is used for analyzing the volatile substances in the existing mass spectrum technology. The ionization source is used for ionizing molecules of a sample to be detected; the mass spectrometric detection method of the ionization source comprises the steps that stable low-temperature plasma is generated under the atmospheric pressure condition through radio frequency discharge, the low-temperature plasma directly interacts with an introduced to-be-detected sample, volatile substance molecules in the to-be-detected sample are efficiently ionized, and then generated ions are introduced into a mass spectrometer for analysis. The device has the advantages of being simple in structure, convenient to operate, free of complex sample pretreatment, high in analysis speed and the like, and an efficient and economical new way is provided for rapid and direct detection of volatile substances.

The invention relates to the technical field of tobacco chemical analysis, in particular to a multistage mass spectrometry identification method for chemical structures of sucrose esters in tobacco and tobacco products, which comprises the following steps: crushing and extracting a tobacco product sample; carrying out solid-liquid separation and filtration to obtain a liquid to be detected; separating the liquid to be detected by adopting hydrophilic interaction chromatography; performing triple quadrupole-ion trap tandem mass spectrometry analysis on the components separated in the step S2 by adopting an electrospray ion source in a positive ion mode to sequentially obtain mass spectrometry information of parent ions, daughter ions and grandchild ions; and determining the chemical structure of the sucrose ester based on the mass spectrum information of the parent ion, the daughter ion and the grandchild ion measured in the step S3. According to the method, complex pretreatment steps are not needed, sucrose esters with different configurations can be identified more efficiently, interference can be effectively eliminated, and substituent group structure information of a low-content target object can be scientifically confirmed.

The application belongs to the technical field of analytical chemistry, and discloses a qualitative analysis method of ethinyl estradiol and degradation products thereof, which comprises the following steps: determining an accurate mass database and a mass spectrum library of the ethinyl estradiol and degradation products thereof to be detected by using an ultra-high pressure liquid chromatography-quadrupole-electrical field orbitrap high resolution mass spectrometer; detecting the sample by using the ultra-high pressure liquid chromatography-quadrupole-electrical field orbitrap high resolution mass spectrometer; and comparing and analyzing the detection result of the sample with the established accurate mass database and mass spectrum library, so that when the detection result matches the information of the accurate mass database and mass spectrum library, it is determined that the ethinyl estradiol and degradation products thereof to be detected are detected in the sample. The application can realize high-precision qualitative analysis of the sample to be detected by searching for parent ions and daughter ions of the ethinyl estradiol and degradation products thereof by using the ultra-high pressure liquid chromatography-quadrupole-electrical field orbitrap high resolution mass spectrometer, and establishing a high-resolution database.

An ion source includes: an atomizer configured to continuously introduce a liquid sample and atomize the liquid sample; a heating and mixing chamber configured to vaporize the atomized liquid sample; and a charge supply unit configured to ionize the vaporized liquid sample. The charge supply unit has a positive pressure with respect to the heating and mixing chamber. The vaporized liquid sample and a gaseous seed ion supplied from the charge supply unit are mixed in the heating and mixing chamber. An auxiliary gas for adjusting a gas flow rate in the heating and mixing chamber can be introduced into the heating and mixing chamber. The heating and mixing chamber has a chamber outlet configured to introduce the ionized liquid sample into a mass spectrometer. The chamber outlet is connected to a first pore of the mass spectrometer.

This invention relates to the field of compound analysis and detection, and more specifically to a method for detecting NMP in soil. The method includes sample pretreatment, extraction, purification, concentration, and LC-MS / MS detection: soil samples are purified, coarsely separated using a quartering method, freeze-dried for dehydration, ground, sieved, and homogenized; extracted with deionized water, the supernatant is collected by low-speed shaking and high-speed centrifugation; purified using an HLB solid-phase extraction column activated with methanol and water, concentrated and diluted to volume with nitrogen blowing before detection. Chromatography uses a C18 column with a trapping column, eluted with formic acid-water and formic acid-acetonitrile gradients; mass spectrometry uses electrospray ionization in positive ion mode with multiple reaction monitoring, using a precursor ion of 100, a quantitative product ion of 58.1, and a qualitative product ion of 69.1 for qualitative and quantitative analysis. This method avoids target analyte loss, reduces matrix interference and background contamination, has high sensitivity, accurate qualitative analysis, and stable recovery rate (98.9% spiked recovery), filling the gap in domestic methods for the dedicated detection of NMP in soil, and is suitable for site investigations and environmental monitoring.

A data acquisition method and ion mobility spectrometry-mass spectrometer (100) capable of effectively adapting to DDA or DIA, the data acquisition method comprising a pre-acquisition step (S1), a parent ion selection step (S2) and a daughter ion acquisition step (S3), the pre-acquisition step (S1) obtaining an ion mobility spectrometry-mass spectrometry two-dimensional heat map, the daughter ion selection step (S2) obtaining a daughter ion two-dimensional heat map, and the daughter ion acquisition step (S3) obtaining a daughter ion two-dimensional heat map; in the parent ion selection step (S2), the ion mobility analyzer (2) is configured to be in a filtering mode, parent ions are selected according to the ion mobility spectrum-mass spectrum two-dimensional heat map, and the mobility selection range of the ion mobility analyzer (2) and the mass selection range of the quadrupole mass filter (3) are correspondingly set. The data acquisition method solves the problems that an existing data acquisition method is limited in dynamic range and low in scanning efficiency.

The invention discloses a detection method of a monacolin compound. According to the application, a non-targeted screening thought is adopted, four key daughter ions of the monacolin compound are found for the first time, and non-targeted screening methods of the monacolin compound based on key daughter ion detection are respectively established in a high-resolution mass spectrum and a triple quadrupole mass spectrum by utilizing the property that the compound is easy to crack in a source in a mass spectrum; the distribution and the content of the monacolin compound can be exclusively presented. Compared with a basic analysis method of original substances, the method has the advantages that secondary mass spectrum analysis is not needed, the retention time of the compounds can be quickly locked, and the monacolin compounds are subjected to non-targeted screening; compared with the original analysis method of the monacolin compound, the method can filter out a large part of interference of other compounds, and specifically shows the distribution and content of the monacolin compound. The method can be applied to fermentation products of monascus, aspergillus terreus and other monacolin compound producing strains and products of the fermentation products to detect distribution and relative content of the monacolin compounds, and can also be applied to quality control methods such as establishment of monacolin compound fingerprints, content determination and the like in the matrix.

The invention discloses an in-source cracking controllable pulse direct-current arc induced nano-liter electrospray ionization source and mass spectrum combined system and a detection method. The system comprises a mass spectrum, a quartz capillary tube, a metal coil, a positive wire, a negative wire and a direct-current arc generator. The high charge density characteristic of pulse direct-current arc plasma and the solution polarization effect induced by a metal coil are combined to construct a dual-drive ionization system. Under low voltage, molecular ion integrity is maintained; under high voltage, the characteristic fragment ion strength is obviously enhanced, the compound structure information can be obtained without depending on tandem mass spectrometry, and the problems of time consumption and sample consumption of nanoliter electrospray ionization source analysis are effectively solved. The pulse direct-current arc provides high-density positive and negative charges, the metal coil strengthens directional migration of charged species to the tip of the capillary tube through potential difference, and ionization stability and efficiency are remarkably improved.

The application provides an animal brain metabolite identification method based on mass spectrometry imaging technology and application, and establishes a mouse brain tissue slice endogenous metabolite DESI-MSI analysis method based on mass spectrometry imaging technology, which comprises the following steps: after preparing metabolite control sample imaging samples and brain tissue slice imaging samples, multiple animal brain tissues are attached to the same glass slide, mass spectrometry imaging condition optimization is carried out by using the control sample imaging samples, and mass spectrometry imaging analysis is carried out by using the brain tissue slice imaging samples; the image of the biological sample is divided into multiple structure regions in combination with tissue morphological characteristics; for the structure regions, multivariate statistical analysis is carried out to obtain different metabolites in different structure regions; metabolite identification is carried out based on parent ions and characteristic daughter ion profiles; and the method is used for disease mechanism research and drug intervention effect evaluation on diseases.

The invention discloses a desorption electrospray and secondary photoionization mass spectrometry imaging device combined with an ion funnel, which comprises a double-light-source secondary ionization component, a two-stage ion funnel, a desorption electrospray ionization source and a three-degree-of-freedom displacement imaging platform for carrying a glass slide of a measured object, the desorption electrospray ionization source is arranged above the three-degree-of-freedom displacement imaging platform and located on one side of the glass slide, an electrospray sampling pipe for sampling molecule-ion droplet clusters is arranged at an inlet of the double-light-source secondary ionization assembly, and the electrospray sampling pipe is arranged above the three-degree-of-freedom displacement imaging platform and located on the other side of the glass slide; an outlet of the double-light-source secondary ionization assembly is connected with an inlet of the two-stage ion funnel, and an outlet of the two-stage ion funnel is externally connected with mass spectrometry equipment. Through the integrated design of double-light-source same-cavity secondary ionization, gas phase doping and the two-stage ion funnel, the ionization efficiency and the ion transmission efficiency of the to-be-analyzed object can be remarkably improved.

The invention discloses a thermal mass spectrometry-based metal precursor pyrolysis characteristic detection method, relates to the technical field of precursor pyrolysis characteristic detection, and aims to solve the problem that the comprehensive purity and impurity content of a product cannot be comprehensively evaluated by a current metal precursor characterization method. A metal precursor is promoted to volatilize in a constant-temperature or temperature-rising heating mode under the protection of inert gas, a thermal weight loss curve is drawn according to the correlation between residual weight and time and temperature, meanwhile, along with decomposition of substances, the weight loss curve jumps, different types of molecular ion fragments can be detected through the combined mass spectrum, and qualitative analysis is achieved. The volatilization rate and the decomposition characteristic of the precursor are represented through a curve and a molecular ion peak, volatilization and decomposition products are quantified through the thermal weight loss proportion and the acquisition proportion of molecular ion fragments, and finally, non-volatile evaporation residues remaining are used as the non-volatile matter impurity content of ultra-pure chemicals. Qualitative and quantitative detection of the purity, impurity components and decomposition characteristics of the metal precursor is realized.

Disclosed is a method, and a system that executes such a method, for elucidation of molecular structures from raw liquid chromatography tandem mass spectrometry (LC-MS / MS) data. The method involves obtaining mass spectrum data, comprising MS1 and MS2 data, from the raw LC-MS / MS data. Compound peaks are then detected by denoising and deconvoluting individual compound fingerprints from the MS1 data. A type of charged adduct corresponding to each precursor molecular ion represented in the MS1 data is determined, and MS1 intensities of an isotope distribution signature for each charged adduct are then obtained. MS2 spectra can subsequently be extracted for each compound corresponding to a compound peak, based on each detected compound peak, charged adduct and MS1 intensities. From this information, a molecular structure can be elucidated from the MS2 spectra by comparing the MS2 spectra to a reference library of reference MS2 spectra and corresponding molecular structures.

The application discloses a kind of carbon positive ion mass spectrometer device based on C + Ion is carried out 14 C analysis method belongs to the technical field of nuclide analysis.The method comprises the following steps: eliminating C-H molecular ion interference by stripping target using specific gas through the way of sectional stripping and charge exchange, then forming C ‑ Ion by charge exchange target of non-metal gas, cooperating with pre-focusing, post-focusing and magnet analysis, to obtain high-intensity C ‑ Ion current intensity;C + Ion current intensity reaches 6-7 mA, C ‑ Ion current intensity after charge exchange reaches 260 μA; the specific gas is any one or more of He gas, Ar gas and N2 gas, and the non-metal gas is any one or more of H2, CH4, C2H4 and C4H 10 . In the application, the C + Ion current intensity generated by ion source is several times higher than that of C 2+ , and the efficiency of generating C + by charge exchange using C 2+ and C ‑ is close, so the efficiency of C + analysis based on C 14 can be several times higher than that of using C 2+ .

The invention discloses a mass spectrometric analysis method for synchronous screening of antibiotics and conversion products in water, and relates to the technical field of environmental analytical chemistry, and the mass spectrometric analysis method comprises the following steps: acquiring and processing a sample to obtain a separated chromatographic fraction and generate initial mass spectrometric data; and executing full-scanning and data-dependent mass spectrum acquisition to obtain a three-dimensional mass spectrum data set. And performing feature matching based on a preset database to generate a candidate compound list. And performing dynamic time alignment correction by using the correlation between the candidate compound retention time deviation and the internal standard substance retention time. And carrying out similarity scoring on the experimental sub-ion spectrogram and the theoretical sub-ion spectrogram. And performing score assignment sorting and false positive filtering in combination with the correction result and the spectrogram score to generate a final identification result. And calculating the quantitative concentration according to the mass spectrum response intensity. According to the method, through dynamic correction of retention time and multi-dimensional assignment verification, the accuracy and reliability of compound identification in a complex water body matrix are improved.

This invention discloses a method for determining polyamines in breast milk and dairy products by gas chromatography-tandem mass spectrometry (GC-MS / MS), comprising: taking 20–200 μL of breast milk or dairy products, adding an isotope mixed standard solution, mixing well, then adding lysis buffer, vortexing thoroughly, centrifuging, taking the supernatant, centrifuging to concentrate and drying, resuspending the dried sample in a mixture of ethyl acetate and trifluoroacetic anhydride, then derivatizing in a water bath at 40–80 °C for 0.5–3 hours, continuing centrifugation to concentrate and dry after derivatization, redissolving in dichloromethane, performing solid-phase extraction purification, blowing the purified solution to near dryness with nitrogen, adding 20–200 μL of a mixture of isopropanol and ethyl acetate to redissolve, and performing GC-MS / MS detection; qualitatively identifying the polyamines based on the qualitative ion pairs and retention times; substituting the ratio of the peak area of ​​the quantitative ion of the polyamine to the peak area of ​​the quantitative ion of the deuterated isotope internal standard into the matrix-matched internal standard curve of the polyamine to obtain the concentration of the polyamine.

The invention relates to a method for analyzing a sample comprising one or more molecules of interest by a mass spectrometer, comprising ionizing a multitude of molecules and / or fragments thereof comprised within a sample to obtain a multitude of molecule ions (source ions), and performing mass spectrometry (MS) analysis comprising a. analyzing the molecule ions and / or fragments thereof in a MS1 measurement, thereby acquiring ion mass spectral data of at least a fraction of the molecule ions and / or fragments thereof (source ions) comprising their mass to charge ratio (m / z), b. / c. isolating a first fraction and a second of the molecule ions (precursor ions) having a m / z within a first m / z range (mz1; isolation window) and a second m / z range (mz2; isolation window), using a mass filter device, wherein the first m / z range is selected based on the ion mass spectral data acquired in step a. or one or more iterations of step a. and / or e., and wherein the second m / z range (mz2) overlaps with the first m / z range (mz1), d. fragmenting at least a fraction of the molecule ions (precursor ions) isolated in steps b. and c., separately, to obtain a multitude of biomolecule fragment ions from each of the respective fragmented molecule ions (precursor ions), and e. analyzing the multitude of biomolecule fragment ions in one or more MS2 measurement, thereby acquiring ion mass spectral data of the analyzed biomolecule fragment ions.

Inductively coupled plasma (ICP) analyzers use an ICP torch to generate plasma in which the sample is atomized and ionized. Analysis of the atomic ions can be performed using atomic analysis, such as mass spectrometry (MS) or atomic emission spectrometry (AES). Particle-based ICP analysis involves analyzing particles (e.g., cells, magnetic beads, or laser ablation plumes) by atomizing and ionizing them in an ICP torch chamber followed by atomic analysis. In mass cytometry, the mass tags of the particles are analyzed using mass spectrometry, such as ICP-MS. The systems and methods of this application include one or more of the following: a removable ICP torch holder assembly, an external ignition device, an ICP induction coil including annular fins, a particle-suspended sample introduction jet, and its ICP analyzer.

The invention discloses a laser ablation ionization source Fourier transform ion cyclotron resonance mass spectrometer for gas phase ion molecule reaction. The mass spectrometer comprises a laser ablation ion source module, a single focusing lens module, a Fourier ion cyclotron resonance module, a reaction gas molecule sample introduction module and a reverse ion excitation system module which are connected in sequence. According to the mass spectrometer, the switchable laser stripping ion source can provide ions in different energy states, the ion molecule reaction module provides target reactant molecules, and the ion cyclotron resonance reaction tank can analyze mass-to-charge ratio information and concentration information while providing an ion molecule reaction place. The comprehensive analysis with high sensitivity, high flux and high resolution is realized, the comprehensive analysis of ion molecule reaction is assisted, and a brand new tool is provided for increasing analysis requirements.

The application discloses a radio frequency enhanced and convergent ion source for mass spectrometry, comprising a VUV light source, an ion source cavity, an auxiliary gas sampling tube, a push-pull electrode, a lamp electrode, a sample sampling tube, an enhanced reaction zone, an ion convergent zone and an ion extraction electrode. The reagent ion generation method determines the reagent ion species and purity, the molecular ion reaction efficiency and the ion transmission efficiency in the source determine the detection sensitivity of the chemical ionization source. In order to further improve the detection performance of the chemical ionization mass spectrometry, the application designs a radio frequency enhanced and convergent ion source, the reagent ions are generated by the vertical irradiation of the VUV light source, the selection of the reagent ions is facilitated and the influence of photoelectrons can be eliminated; in addition, the radio frequency enhanced reaction zone and the radio frequency ion convergent zone are introduced to improve the molecular ion reaction efficiency and the ion transmission efficiency. The application can effectively improve the detection sensitivity and the universality of the chemical ionization mass spectrometry, and has wide application prospects in the fields of atmospheric environment monitoring, industrial processes, medical diagnosis and the like.

The invention provides a method for synchronously measuring main components of herba epimedii in a sample based on an LCMS / MS (Liquid Chromatography Mass Spectrometry / Mass Spectrometry) technology. Performing LC-MS / MS analysis on the reference substance mother liquor, recording the retention time, parent ion, characteristic daughter ion and characteristic fragment ion information of each reference substance, and establishing a qualitative recognition database; preparing a test solution of the sample; wherein the sample is at least one of a herba epimedii raw material medicine, a traditional Chinese medicine preparation containing herba epimedii and a biological sample; performing LC-MS / MS analysis on the test solution to obtain a mass spectrum ion chromatogram; comparing the mass spectrum ion chromatogram with a qualitative identification database, and qualitatively judging whether the test solution contains a target component corresponding to the reference substance or not. The method can be used for synchronously and qualitatively detecting preparations such as herba epimedii raw material medicine, GuShukang capsules and Xintong oral liquid as well as in-vivo biological samples such as serum, liver tissue and kidney tissue, and in-vitro-in-vivo full-chain component identification is realized.

The invention relates to an ion processing method and device of a collision pool device, computer equipment, a storage medium and a computer program product. The method comprises the following steps: under the condition that ions are detected to enter a collision pool device, controlling the ions to be enriched on an axis in the collision pool device; based on the traveling wave driving force and the airflow dragging force on the axis, cooperatively screening out target ions from the ions; controlling the target ions to collide and crack with the collision gas to obtain daughter ions of the target ions; when it is detected that the daughter ions move to an axial bound electric field in the collision pool device in the axial direction, the daughter ions are bound through the axial bound electric field; the axial bound electric field is constructed through reverse direct-current voltage; the axial bound electric field is controlled to release daughter ions through the first alternating voltage, and the released daughter ions are led out of the collision pool device. By adopting the method, the enrichment effect, the screening effect, the separation effect and the extraction effect of ions can be improved.

The invention relates to the technical field of polypeptide detection, in particular to a method for rapidly distinguishing and determining leucine and isoleucine in a polypeptide sequence based on tandem multistage high-resolution mass spectrometry. The method comprises the following steps: (1) performing HCD fragmentation on parent ions or daughter ions of polypeptide to generate imine ions related to leucine and / or isoleucine; (2) carrying out CID fragmentation on the imine ions, and detecting relative peak intensities of m / z 44 + / -0.2 and m / z 69 + / -0.2 generated by fragmentation in a mass axis range of m / z 40-90; and (3) judging the types of leucine and isoleucine in the polypeptide according to the relationship between the relative peak intensities of m / z 44 + / -0.2 and m / z 69 + / -0.2. The method provided by the invention is higher in fragmentation efficiency and confidence degree, and provides a basis for rapid and accurate identification of leucine and isoleucine.

The invention discloses a method for detecting N-nitroso bisoprolol impurities in bisoprolol amlodipine tablets, and belongs to the field of drug impurity detection. The method comprises the following steps: preparing a reference substance solution and a test sample aqueous solution (ultrasonic dispersion and constant volume centrifugation), and then detecting by adopting HPLC-MS / MS: a chromatographic column is a C18 column (the particle size is 2-3 microns, the inner diameter is 2.1-4.6 mm, and the length is 100-250 mm), a mobile phase contains 0.1-0.5% of formic acid, 5-20 mM of an ammonium acetate aqueous solution and methanol / acetonitrile, and gradient elution is carried out; the mass spectrum is in an ESI positive ion mode, MRM scanning is carried out, and characteristic ion pairs (parent ions 372 + / -1amu, daughter ions 145 + / -1amu and the like) are monitored. The method is simple and convenient in pretreatment, environment-friendly in solvent, high in sensitivity and good in durability, trace impurities can be accurately detected, and reliable support is provided for quality control of bisoprolol amlodipine tablets.

The invention discloses a method and a system for detecting carbon-13 isotope abundance in carbon dioxide. The method comprises the following steps: preparing a 13C-benzoic acid sample by using carbon dioxide containing 13C; the method comprises the following steps: dissolving a < 13 > C-benzoic acid sample in a solvent to prepare a solution to be detected; and carrying out liquid chromatography separation on the solution to be detected, and carrying out ion monitoring in a negative ion mode by adopting mass spectrum so as to obtain the < 13 > C isotope abundance. According to the invention, gaseous 13CO2 is converted into solid benzoic acid which is easy to analyze by LC-MS through a specific chemical derivatization reaction, so that abundance measurement of gas isotopes is converted into intensity ratio measurement of specific molecular ion peaks in a liquid sample, and a new path for isotope abundance detection by using conventional analysis equipment is opened up; the method gets rid of dependence on expensive and special IRMS instruments, can be implemented in any laboratory equipped with conventional LC-MS, and greatly reduces the analysis threshold and cost.

The present application belongs to the field of analysis and detection, and particularly relates to a method for analyzing the content of quercetin-3-ol in a biological matrix. The method comprises: mixing a biological matrix sample with a precipitant for protein precipitation treatment, separating to obtain a supernatant, and taking the supernatant as a test solution; and using liquid chromatography-tandem mass spectrometry to analyze the concentration of quercetin-3-ol in the test solution. Through sample separation pretreatment and optimization of liquid chromatography and mass spectrometry parameters, the lower limit of quantification of the method can reach 20 ng / mL, which can meet the detection requirements of trace quercetin-3-ol in vivo; the standard curve is linear in a wide concentration range, and is suitable for sample analysis at different concentration levels; in mass spectrometry detection, the MRM detection mode is used, and the dual selectivity of parent ions and daughter ions is used to effectively eliminate the interference of complex components in the biological matrix, and the method has high selectivity and accuracy.

This application relates to the field of analytical chemistry technology and provides a method for detecting perfluorinated and polyfluoroalkane (PFAS) compounds in petroleum-contaminated soil. The method includes: freeze-drying, pulverizing, and sieving the petroleum-contaminated soil; mixing the sieved soil with diatomaceous earth, placing it in an extraction cell for extraction, and collecting the extract; drying the extract, redissolving it with methanol, filtering, and diluting to obtain the sample to be tested; detecting the sample using high-performance liquid chromatography-high-resolution mass spectrometry (HPLC-MS / MS) in negative ion electrospray ionization mode; and identifying compounds based on molecular ion mass, retention time, and peak shape. This application provides a standardized detection method adapted to petroleum-based soil matrices, integrating targeted precise qualitative analysis and non-targeted broad-spectrum screening of PFAS based on rapid solvent extraction and HPLC-MS / MS, solving the problems of low extraction efficiency, poor purification effect, and inaccurate qualitative analysis of PFAS trace detection under strong interference from petroleum hydrocarbons.

The application belongs to the technical field of environmental monitoring and analytical chemistry, and discloses a detection method for the content of methyl tert-butyl ether in soil. The method uses surface functionalized mesoporous silica adsorbent for solid phase extraction, combines ultrasonic assisted extraction with gas chromatography-mass spectrometry analysis, the adsorbent has a pore size of 2.5-4.0 nm, and a surface grafted with bifunctional ligands containing tertiary amine groups and short chain alkyl groups, and has high selectivity and adsorption capacity for methyl tert-butyl ether; the mass spectrometry detection adopts double ion confirmation and intensity ratio criterion, effectively eliminating the interference of structural analogues. Through the design of special adsorption materials, the optimization of the pretreatment process and the construction of the mass spectrometry confirmation logic, the application realizes high sensitivity, high selectivity and high reproducibility detection of trace methyl tert-butyl ether, and can be widely applied to industrial pollution site investigation, farmland soil safety evaluation, groundwater pollution tracing and emergency monitoring of environmental incidents.

The invention discloses a method for detecting a lanthanide metal-1, 3-dione complex based on MALDI-TOF MS. The method comprises the following steps: preparing a detection sample of the lanthanide metal-1, 3-dione complex, then detecting by adopting a reflection mode, and detecting the lanthanide metal-1, 3-dione complex by adopting an MALDI-TOF MS under the conditions that the laser intensity is 45-55%, the voltage multiple is 13.9 * and the room temperature. After sample application, MALDI-TOF MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry) is adopted for detection to obtain relative molecular mass and isotope distribution results. According to the method provided by the invention, the MALDI-TOF MS detection of the lanthanide metal-1, 3-dione complex can be realized, the molecular ion peak of the lanthanide metal-1, 3-dione complex molecule is obtained, the error of the detection result is less than 5ppm, and the detection requirement of high-resolution mass spectrum is met.