134 results about "ESI mass spectrometry" patented technology

The invention relates to an analysis method for characterizing structures and interaction of non-denatured proteins and compounds thereof based on pulse extreme ultraviolet laser dissociation and mass spectrometry detection. Protein interacts with large and small molecules such as metal ions, drug small molecules, protein, nucleic acid or polysaccharide to form a protein compound. Natural protein and protein compound samples in a biocompatible neutral solution enter a gas phase through a non-denaturing electrospray ionization technology, then radiation excitation is performed on the natural protein and protein compound samples through pulse extreme ultraviolet laser, dissociation is induced to generate protein structure characteristic fragment ions, and finally detection and spectrogram recording are performed on the fragment ions through mass spectrum. According to the invention, the technology for characterizing the structure and interaction of the non-denatured protein and the compound of the non-denatured protein by the extreme ultraviolet band laser is realized for the first time internationally, and the method has the remarkable advantages of high sensitivity, high flux, single amino acid site resolution and the like in the aspect of researching fine structures and conformation dynamic changes of protein-protein and protein-micromolecule interaction interfaces.

The invention discloses an online floating electrochemical scanning and electrospray ionization mass spectrometry combined device, relates to the technical field of analytical chemistry, and can improve the electrochemical detection efficiency and detection accuracy. According to the device, a three-electrode probe is arranged in a reaction cavity and is used for containing a target solution to be detected; the floating type electrochemical controller comprises a high-voltage module, a power supply module, a floating electrochemical measurement and control circuit and a three-electrode probe, the high-voltage module raises the first potential of the floating ground end of the power supply module into a second potential; the power supply module is used for converting the voltage of the floating battery into a preset voltage and then supplying power to the floating electrochemical measurement and control circuit; the floating electrochemical measurement and control circuit is used for controlling the three-electrode probe to output a continuous high-voltage signal or a continuous current signal, the continuous high-voltage signal or the continuous current signal acts on a target solution to generate an electrochemical reaction and directly generate spray ions, and the three-electrode probe is used for detecting voltage and current in the electrochemical reaction process of the target solution; and detection voltage and detection current are obtained.

A position control system may obtain image data representing one or more images depicting an inlet of a mass spectrometer and an emitter positioned near the inlet, and adjust a position of the emitter relative to the inlet to an optimal position at or near a reference position relative to the inlet based on the image data.

An electrostatic separator or precipitator through which an air stream to be cleaned of particles flows in a longitudinal direction includes at least one electrospray ionization source, which is supplied with a positive potential and can be implemented, for example, by the tips of a graphite fiber bundle, and a collector unit arranged downstream for particle separation and having parallel collector and driver plates. The ion flow from the corona zone is additionally homogenized and spread by an upstream collector element, in particular a collector grid, upstream of the at least one electrospray ionization source, so that high particle separation rates can be achieved with minimal ozone emissions. Alternatively, or in addition, the ion flow from the corona zone can be homogenized downstream of the at least one spray ionization source by one or more border counter-electrodes.

The present invention relates to the field of analytical chemistry, and discloses a mass spectrum ionization element for macrolide antibiotic detection and a preparation method thereof, the mass spectrum ionization element comprises: a conductive substrate made of stainless steel; the adsorption layer is attached to at least part of the surface of the substrate, the adsorption layer is formed by a boric acid functionalized covalent organic framework, and the boric acid functionalized covalent organic framework is of a polycyclic structure composed of repeated units shown in the formula I in the specification. The mass spectrum ionization element is uniform in coating, high in selectivity on macrolide enriched antibiotics in a complex matrix and high in enrichment capacity, an eluent of the mass spectrum ionization element can be used for detection based on a liquid chromatography method and can also serve as a mass spectrum ion source solid substrate, mass spectrum detection is conducted through electrospray ionization, the detection steps are simple, and the mass spectrum ionization element is suitable for mass spectrum detection. And the detected background noise is low.

The invention relates to the technical field of food safety detection, in particular to a method for detecting urea in bean sprouts and application thereof.The method comprises the following steps that smashed bean sprouts are subjected to two times of ultrasonic extraction and centrifugation, supernate is combined, and an extracting solution is obtained; fixing the volume and filtering to obtain a to-be-detected solution; detecting the liquid to be detected by using liquid chromatography-tandem mass spectrometry; an extraction solvent for ultrasonic extraction is a 5% formic acid-acetonitrile composite solution; the conditions of the liquid chromatography-tandem mass spectrometry are as follows: the chromatographic conditions are as follows: a chromatographic column is an HILIC column; the sample size is 10 [mu] L; a mobile phase is a mixed solution of a 0.02 mmol / L ammonium acetate buffer salt solution and acetonitrile, and isocratic elution is carried out; the flow rate is 0.3 mL / min; the column temperature is 40 DEG C; mass spectrum conditions are as follows: an electrospray ionization (ESI) positive ion mode, electrospray voltage of 4000 V, sheath gas pressure of 30 psi, auxiliary gas pressure of 5 psi, capillary heating temperature of 300 DEG C and scanning mode of MRM. The method disclosed by the invention is free from substance interference, high in sensitivity, accurate in result, low in cost and high in efficiency, and can be used as a standard detection method.

The invention provides a method for detecting the blood concentration of elacycline in serum. The method comprises the following steps: pretreating a human serum sample; then detecting by adopting liquid chromatography-mass spectrometry, wherein a liquid chromatography condition mobile phase comprises ultrapure water (a mobile phase A) containing 0.1% of formic acid and acetonitrile (a mobile phase B); the temperature of the chromatographic column is kept at 45 DEG C, and the sample size is 2L; the flow velocity of the mobile phase is set to be 0.3 mL / min, and the total operation time is 4.5 minutes; in mass spectrum conditions, a positive electrospray ionization mode is adopted, multiple reaction monitoring (MRM) is adopted, and multi-reaction monitoring is adopted as a scanning mode. The method is high in sensitivity, the lowest quantitative concentration can reach 50 ng / mL, and accurate, rapid and sensitive determination of the elacycline in the human serum can be realized.

The utility model discloses a droplet microextraction-flow type electrospray ionization device, which belongs to the technical field of chemical analysis and comprises a digital peristaltic pump, a direct-current high-voltage power supply, a stainless steel two-way connector and a conductive metal transmitting tube. A transmission hose is arranged on the digital peristaltic pump, one end of the conductive metal transmitting tube is connected with the transmission hose of the digital peristaltic pump through a stainless steel two-way connector, the other end of the conductive metal transmitting tube corresponds to a mass spectrometer inlet and is used for generating electrospray, and the direct-current high-voltage power supply is electrically connected with the conductive metal transmitting tube. The direct-current high-voltage power supply applies voltage to the conductive metal transmitting tube; according to the droplet microextraction-flow type electrospray ionization device adopting the structure, micro-droplet flow type sample injection and non-contact flow type sample injection are combined, and electrospray can be stably generated under the condition of not depending on gas assistance.

The invention relates to a spray head for electrospray ionization (ESI). The invention also relates to a method for producing a spray head according to the invention and to the use of a spray head according to the invention for electrospray ionization (ESI). The invention also relates to a chromatography column comprising a spray head according to the invention and to a device for carrying out electrospray ionization (ESI) comprising a spray head according to the invention or comprising a chromatography column according to the invention.

To provide a method and system for protein characterization using online chromatography and electrospray ionization mass spectrometry.SOLUTION: A method for protein characterization comprises the steps of: contacting a sample including protein to a chromatography system with a size exclusion chromatography resin; cleaning the size exclusion chromatography resin using a mobile phase to obtain an eluent containing the protein; and characterizing the protein in the eluent using an electrospray ionization mass spectrometer under non-denaturing conditions.SELECTED DRAWING: Figure 2

The application discloses a kind of based on plasma atomization gas auxiliary electric spray ionization method, comprising the following steps: a) sample solution is introduced into electric spray needle;B) open plasma initiation device, make plasma initiation device discharge and generate plasma in plasma atomization gas gas path;C) atomization gas is introduced into plasma atomization gas gas path, and the atomization gas under the action of plasma forms plasma atomization gas;D) open high-voltage power supply, and sample solution is under the action of high-voltage electricity and plasma atomization gas and generates spray and forms sample ion, and the sample ion formed enters mass spectrometer by mass spectrometry inlet channel.This application can improve sensitivity, and under the premise that compound fragmentation dissociation does not occur, it is used for electric spray unfriendly solvent and difficult to detect low polarity compound detection, which can be compatible with normal phase liquid chromatography commonly used solvent, and can also reduce the influence of common complex matrix effect in electric spray ionization.

The invention discloses a plasma electrospray fusion ionization source and mass spectrum combined system and a detection method. The plasma electrospray fusion ionization source and mass spectrum combined system comprises a coaxially nested electrospray needle, a sample injector, an ultrahigh voltage generator, a grounded metal grid mesh, a mass spectrometer and a detector thereof. A grounded metal grid is installed between a spray needle and a mass spectrum inlet, voltage is applied to the spray needle, carrier gas is excited to generate plasmas, the macroscopic plasmas at the front end of the spray needle are fused with electrospray, and the plasmas and micro-droplets at the tip of the spray needle are fused. According to the unique ionization source constructed by the plasma-micro-droplet fusion system, on one hand, the ionization efficiency is improved, mass spectrum signals are enhanced, the application range of analytes is widened, excellent sensitivity to high-polarity compounds is kept, and effective ionization and detection of low-polarity compounds are achieved; on the other hand, higher energy and active species are provided for the micro-droplet reaction, the energy barrier required by traditional synthesis is broken, and efficient spontaneous product generation of the micro-droplet chemical reaction is achieved.

The present disclosure relates to an apparatus and method to achieve electrospray ionization at femtoliter / minute to nanoliter / minute flow rates including relatively rapid alternation between such flow rates within the same device. These flow rates provide enhanced and relatively more uniform ionization of sprayed compounds for subsequent analytical evaluations.

The invention discloses an electrospray ionization mass spectrometry ion source based on a low-frequency alternating-current voltage strategy and a use method of the electrospray ionization mass spectrometry ion source. The ion source comprises a nanoliter electrospray needle used for loading a sample solution; the metal electrode is inserted into the nanoliter electrospray needle and is in direct contact with the sample solution; the signal generator has a plurality of signal output functions; and the high-voltage amplifier has a voltage amplifying function, a signal input end is connected with the signal generator, and an output end is connected with the metal electrode. Firstly, a signal generator is used for generating an alternating current signal with specific waveform, frequency, peak-to-peak value and duty ratio, and the signal is amplified by a high-voltage amplifier and then directly acts on a nanoliter electrospray needle to generate electrospray; meanwhile, the amplified signal is monitored in real time by an oscilloscope. The low-frequency alternating-current nano-liter electrospray ion source involved in the invention is named as LFAC-nESI. Compared with a conventional nanoliter electrospray (nESI) ionization method, the method provided by the invention has an online desalting function, can significantly improve the signal-to-noise ratio and analysis sensitivity of a to-be-detected object, and is more practical.

The invention discloses a high-beam ion soft landing device based on a multistage difference technology, and belongs to the technical field of surface scientific sample preparation. The device comprises an electrospray ionization source, an ion transmission device, an ion deposition device and a sample transfer device which are connected in sequence. The ionization source couples high voltage to the solution through the spray needle fixing mechanism integrating the three-dimensional displacement table and the metal conductive connecting piece, and electrified micro-droplets are generated. The transmission device adopts a combination of a four-stage differential air exhaust cavity and a replaceable ion lens with a gradually increased aperture, so that efficient focusing and transmission of ions are realized, and desolvation is completed through a heating capillary tube. The deposition device drives a multi-clamping-groove vertical sample frame through a magnetic coupling sample transfer rod, and applies a deceleration electric field to a sample support by using an external bias power supply, so that ions are softly landed on a substrate with low kinetic energy. According to the invention, an expensive mass spectrum assembly is abandoned, and through linkage of all parts, high-flux and high-integrity clean deposition of macromolecules and heat-sensitive samples is realized while the cost is remarkably reduced.

The invention relates to a novel analysis method for carrying out lipid gas phase dissociation by adopting pulse extreme ultraviolet laser and characterizing a lipid molecular structure by analyzing dissociated fragment ions through mass spectrometry. A lipid sample enters a gas phase through electrospray ionization, then lipid molecules with accurately selected mass are efficiently excited and dissociated by adopting extreme ultraviolet laser to generate fragment ions with sequence and structural characteristics, and finally the fragment ions are detected through mass spectrum. According to the method, efficient extreme ultraviolet light dissociation of lipid molecules can be achieved, structural characteristics such as head groups, sn positions, double bond positions and cis-trans isomerism of the lipid molecules can be accurately determined through fragment ion spectrogram analysis, and accurate identification and distinguishing of complex lipid isomers are achieved.

The invention relates to the technical field of analysis and test technologies and medical methods, and discloses a reagent and a method for molecular structure analysis of an estrogen isomer, which are based on cyclodextrin and are used for molecular structure analysis of an alpha / beta-E2 / E3 isomer. The reagent comprises gamma cyclodextrin (gamma-CD), beta-CD and a mixed aqueous solution of compounds containing different metal ion ligands, the molecular formula of the beta-CD is C42H70O35, the molecular weight of the beta-CD is 1134.98, and the compound containing the metal ions is salt of any metal ion or soluble alkali containing the metal ions. According to the method, an alpha / beta-E2 / E3 sample, CD, a compound containing metal ions, such as monovalent metal or divalent metal ions and the like are simply prepared into a mixed solution, then non-covalent compound ions of alpha / beta-E2 / E3-gamma-CD / beta-CD-containing metal ions are generated by utilizing electrospray ionization, and then the ion mobility spectrometry of the non-covalent compound ions is measured by utilizing an ion mobility spectrometry technology. And different position structure information of alpha / beta-E2 / E3 molecules can be obtained.

The invention relates to the field of detection, in particular to a method for determining the residual quantity of methoprene and methoprene in citrus through pre-column derivatization liquid chromatography-tandem mass spectrometry, and the method comprises the following steps: S1, preparation of a standard sample and a to-be-detected sample: S11, preparation of the standard sample, and S12, preparation of the to-be-detected sample; s2, preparation and derivation of a standard sample solution and a to-be-detected sample solution: S21, extraction, S22, purification and S23, derivation; s3, measuring; s4, establishing a linear equation; and S5, analyzing the sample to be detected. The technical problems that in the prior art, the ionization efficiency of methoprene and methoprene in the electrospray process is low due to the non-polar property of methoprene and methoprene, and electrospray ionization tandem mass spectrometry detection of methoprene and methoprene lacks the sensitivity required by trace analysis can be solved. The detection sensitivity of methoprene and methoprene in citrus fruits can be obviously improved.

This invention relates to the field of traditional Chinese medicine component research technology, specifically to a method for constructing fingerprint spectra based on the antioxidant active components of Ganoderma lucidum and its application. First, a method for ultrasonic-assisted acid hydrolysis of crude Ganoderma lucidum polysaccharides guided by free radical scavenging activity was constructed. This method is efficient, easy to operate, and can effectively reflect the free radical scavenging activity of the depolymerized Ganoderma lucidum polysaccharides. Hydrophilic chromatography-electrospray ionization detector-electrospray mass spectrometry was used to acid hydrolyze and analyze 52 batches of Ganoderma lucidum polysaccharides from different sources. Further, combined with grey relational analysis and partial least squares regression analysis, 12 common activity peaks were screened, establishing fingerprint spectra based on the antioxidant active components of Ganoderma lucidum. Finally, principal component analysis and partial least squares discriminant analysis were used to analyze the fingerprint spectra based on the antioxidant active components of Ganoderma lucidum for standard Ganoderma lucidum, Ganoderma sinense, Ganoderma applanatum, Ganoderma lucidum var. truncatum, and sample Ganoderma lucidum, respectively, achieving the identification of Ganoderma lucidum varieties.

The present disclosure relates to integrated electrospray emitters and methods of manufacturing the same. An electrospray ionization emitter according to various aspects described herein can include an emitter body formed using fused silica. The emitter body can include a fluid conduit segment including a liquid connection end that has been coated with polyether ether ketone (PEEK) over at least a portion of the liquid connection end. The liquid connection end can have a first outer diameter configured to connect to a sample source to receive a sample liquid for ionization from the sample source. The emitter body can also include an ionization discharge segment fluidically connected to the fluid conduit segment. The ionization discharge segment can have an ionization discharge end coated with a conductive material over at least a portion of the ionization discharge end and configured to have a second outer diameter that allows for ionization of the liquid sample.

The application provides a mass spectrum interface structure and a mass spectrum analyzer, the mass spectrum interface structure comprises a metal electrode, an electrospray ionization needle, a metal plate and an analyzer, the metal electrode is connected to the tail end of the electrospray ionization needle, the head end of the electrospray ionization needle is provided with a nozzle and faces the metal plate, the metal electrode and the metal plate have a positive voltage difference, so that the ions in the electrospray ionization needle are sprayed from the nozzle and generate a blocking current pulse, the electrospray ionization needle is electrically connected with the analyzer, so that the analyzer analyzes the blocking current pulse and obtains the size of the ions. The mass spectrum interface structure and the mass spectrum analyzer provided by the application, the ions in the electrospray ionization needle are sprayed from the nozzle under the action of the voltage, when the ions with a size corresponding to the size of the nozzle are sprayed, a blocking current pulse is generated, the length and the width of the ions can be calculated through the signal amplitude and the blocking time of the blocking current pulse, so that the specific size of the ions is obtained.

The present invention discloses a kit for rapid determination of brucine and strychnine by mass spectrometry, which relates to the technical field of biological detection. The kit for rapid determination of mass spectrometry includes an MCX mixed cationic adsorbent and a pyrrolidone-styrene polymer adsorbent. The kit for rapid determination of mass spectrometry effectively improves the accuracy and sensitivity of detection. Through the method of extraction by multi-well plate - liquid chromatography - tandem mass spectrometry, on a silica-based C18 reversed-phase chromatography column, under specific mobile phase composition and flow rate conditions, the separation of brucine and strychnine from interfering impurities in blood on the silica-based C18 reversed-phase chromatography column and the multi-reaction monitoring (MRM) mass spectrometry detection in the positive ion mode of the electrospray ionization source are realized, and finally the rapid, accurate and highly sensitive detection of brucine and strychnine in blood is achieved.

The invention belongs to the technical field of pharmaceutical analysis, and particularly relates to a biological analysis method for detecting the concentration of hydrocortisone butyrate in blood plasma, which is used for analyzing a compound to be detected in the blood plasma through an LC-MS / MS (Liquid Chromatography-Mass Spectrometry / Mass Spectrometry) method. According to the detection method, a liquid-liquid extraction pretreatment method is preferably adopted, finasteride serves as an internal standard substance, a Shim-pack Velox SP-C18 chromatographic column is adopted, gradient elution and electrospray ionization source tandem mass spectrometry detection are carried out, and the detection method is high in sensitivity, precise, accurate, high in analysis speed, high in sensitivity, high in sensitivity, high in sensitivity, high in sensitivity, high in sensitivity, high in sensitivity, high in sensitivity, high in sensitivity and high in sensitivity. The sample analysis requirement in the clinical research of the hydrocortisone butyrate is met.

Method for the determination of the conformation of at least one biopolymer by using hyphenating mass spectroscopy with chromatographic or electrophoretic separation, wherein a) downstream of the chromatographic or electrophoretic separation electrospray ionization (ESI) is used for generating native or essentially native conformation ions of said of at least one biopolymer in the gas phase; b) these ions, or precursors based on these ions, are selected, preferably based on at least one of mobility, charge state, or a combination thereof, c) these selected ions or precursors are fragmented using a non-ergodic or essentially non-ergodic dissociation to form fragments; d1) the resulting fragments are on the one hand analyzed for their distribution as a function of mass to charge in a survey spectrum, preferably using a selection based on at least one of mobility, charge state, or a combination thereof; d2) the resulting fragments are on the other hand collision activated and then analyzed for their distribution as a function of mobility to charge in at least one spectrum as a function of said collision activation, preferably analyzed using a selection based on at least one of mobility, charge state, or a combination thereof, e) using differential information from d1) and d2) about the fragments to determine which of the fragments resulting from step c) are in a native or essentially native conformation, and using information from the fragments having native conformation for the determination of the conformation of said at least one biopolymer.

The invention provides an analysis method for measuring negative ions in urine based on gas phase ion chromatography, and belongs to the technical field of urine analysis. One of the urine analysis methods based on gas phase ion chromatography can comprise the following steps: injecting a chelating ligand into an analyzer through a continuous sample injector electrospray to obtain a background signal; a to-be-detected urine sample is fed one by one through an online six-way valve automatic sampler, a chelating ligand solution and the urine sample can be fully mixed through an online mixer, electrospray ionization is realized, the mixture enters an analyzer, an ion chromatograph records a sample signal, and a background is deducted to obtain a urine analysis result; wherein the ionization technology is an electrospray ion source. According to the method disclosed by the invention, separation of various ions on the gas phase ion chromatography can be realized; the kit can also be used for qualitatively and quantitatively detecting trace inflammatory factors, trace proteins and other proteins in urine, and can be applied to prevention and treatment of kidney stone.

The invention discloses a bacterial subtype analysis method based on nano electrospray ionization mass spectrometry, and belongs to the field of detection technologies. Detecting the known bacterial liquid by mass spectrometry to obtain a mass spectrum fingerprint spectrum of the bacterial liquid; screening out predicted metabolites according to the mass spectrum fingerprint spectrum of the bacterial liquid; performing mass spectrum detection on the standard substance for predicting the metabolite to obtain a mass spectrum fingerprint spectrum of the standard substance; metabolites corresponding to different bacteria types are checked; then screening out key biomarkers from metabolites corresponding to bacterial types according to importance values of the projection variables; the method comprises the following steps: carrying out discriminant analysis on bacteria on the basis of SPSS software by taking a metabolite-to-charge ratio and mass spectrum peak intensity corresponding to known bacteria varieties as independent variables and the bacteria varieties as grouping variables, so as to obtain a scatter diagram of known sample bacteria, carrying out SPSS analysis on an unknown sample, and comparing with the scatter diagram, so as to confirm the bacterial subtype in the unknown sample. The method can be used for quickly distinguishing bacterial subtypes by using a blood sample.

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 position control system may obtain image data representative of one or more images that depict an inlet of a mass spectrometer and an emitter positioned near the inlet and adjust, based on the image data, a position of the emitter relative to the inlet to an optimum position that is at or near a reference position relative to the inlet.

1. Name of the product in this design: Cryo-electron microscopy sample preparation machine (electrospray ionization technology). 2. Purpose of this design: For preparing frozen electron microscope samples. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: 3D rendering 1.

The invention relates to a spray head for electrospray ionization (ESI). The invention also relates to a method for producing a spray head according to the invention and to the use of a spray head according to the invention for electrospray ionization (ESI). The invention also relates to a chromatography column comprising a spray head according to the invention and to a device for carrying out electrospray ionization (ESI) comprising a spray head according to the invention or comprising a chromatography column according to the invention. The invention further relates to the use of selective laser-induced etching (SLE) or two-photon polymerization (2PP) for producing a spray head according to the invention for electrospray ionization (ESI).