84 results about "Thermal ionization mass spectrometry" patented technology

A sample preparation method is disclosed for volatilization and mass spectrometric analysis of nonvolatile high molecular weight molecules. Photoabsorbing molecules having significant sublimation rates at room temperature under vacuum, and preferably containing hydroxy functionalities, are disclosed for use as matrices in matrix-assisted laser desorption / ionization mass spectrometry. The samples are typically cooled in the mass spectrometer to temperatures significantly below room temperature.

The invention discloses a detection method of a phthalate plasticizer, comprising the following steps: 1. pretreatment: putting a sample to be detected into an organic solvent, and then dissolving and treating to obtain the solution to be detected in which the plasticizer is dissolved; and 2. content determination of the plasticizer: utilizing a gas chromatogram method and a chemical ionization mass spectrometry method to detect the type and the content of the plasticizer in the detected solution, wherein, the chemical ionization reagent used in the chemical ionization mass spectrometry method is composed of isobutane, methane or ammonia. The detection method of the phthalate plasticizer provided by the invention has high qualitative and quantitative accuracy and high quantitative detection sensitivity.

A method and apparatus for conducting mass spectrometry. The mass spectrometry may be accomplished by ion drift-chemical ionization mass spectrometry. One embodiment includes a chemical ionization mass spectrometer comprising an ion drift zone having an ion conductor that transports positive or negative ions. The chemical ionization mass spectrometer further comprises an ion source that produces the positive or negative ions and a mass spectrometer.

A method for directly analyzing a lung cancer tissue sample based on the tissue electro-spray ionization mass spectrometry concretely comprises the steps that an electro-spray extraction ionization source in the tissue sample is set up; an extraction agent, namely, methyl alcohol is sucked through a micro-syringe connected with a quartz capillary, the extraction agent is dripped on the surface of the sample through the quartz capillary, and an injection pump controls the micro-syringe; the lung cancer tissue sample is cut into a piece of which the volume is 1 mm3 and placed at the tip of an acupuncture needle, and the needle tip is inserted into the sample and keep unexposed; the distance between the front end of the sample and an inlet of a mass spectrometer is adjusted, and the tail end of the acupuncture needle, the front end of the sample and the inlet of the mass spectrometer are adjusted to be in a horizontal coaxial state; DC voltage is applied on the acupuncture needle, so that extraction, desorption and ionization happen on the sample, and the sample generates spray which enters the mass spectrometer. According to the method, the information of molecules in the sample can be directly and quickly obtained, and the result shows that the method is a mass spectrometry method which has the advantages that the device is simple, manufacturing cost is low, ionization efficiency is high, and damage to the sample is small.

The invention provides a simple, rapid and cost-effective metal oxide-assisted laser desorption / ionization mass spectrometry (MOALDI MS) without the addition of light-absorbing organic-matrix, comprising the use of (a) an inorganic metal oxide with light absorbing capability as an assisting material to render desorption / ionization of samples in laser desorption / ionization mass spectrometry and (b) a citric acid buffer as the proton source for enhancing the ionization efficiency for analytes. Metal oxide assisting materials is not only restricted to the uses of films. Metal oxide nanoparticles are also suitable to be used as the assisting materials. Low matrix background, stable surface feature, homogeneous sample deposition, and wide detectable mass range are the merits of MOALDI MS.

The invention discloses a uranium isotope abundance measurement method by using carbon nanotubes as an ion emission agent, which comprises the following steps: (1) sample preparation: preparing a carbon nanotube suspension, and pretreating a rhenium strip; (2) sample coating: putting the evaporation rhenium strip on a sample coating device, dripping a uranium solution onto the evaporation rhenium strip, drying, and cooling to room temperature; coating the carbon nanotube suspension on the uranium sample, drying the evaporation rhenium strip, cooling to room temperature, and loading onto a rotary table; and (3) sample measurement: sending the rotary table into an ion source, starting a mass spectrometer, and after the ion current signal intensity reaches the maximum and the signal stays in the most stable state for 3-5 minutes, starting data acquisition of uranium isotope abundance measurement. By using the carbon nanotubes as the ion emission agent for uranium isotope abundance measurement, the invention improves the ion emission property of trace uranium sample in thermal ionization mass spectrometer measurement; and by optimizing the burning strip used by the carbon nanotubes as the emission agent as well as experimental conditions for sample preparation, testing and the like, the invention establishes a novel method for measuring the abundance of trace uranium isotope.

The invention belongs to the technical field of analysis and in particular relates to a device and method for combining electrochemistry with electrospray ionization mass spectrometry. The device is composed of an electrochemical reactor and an electrospray ionization ion source. The electrochemical reactor comprises a work electrode chamber and an auxiliary electrode chamber which are isolated from each other through a diaphragm, the diaphragm has the effects of preventing or delaying a neutral substance from exchanging between the electrode chambers and allowing an ion to exchange with an electric ion. A solution sample can be subjected to electromechanical reaction under the effect of an electrochemical voltage loaded between the work electrode and the auxiliary electrode when flowing in the work electrode chamber. An electrochemically reacted product is protected by the diaphragm and then forms an air-phase ion under the effect of the electrospray ionization work voltage, and the air-phase ion is analyzed by a mass spectrometer. According to the invention, the electromechanical reaction efficiency is higher, the electromechanically reacted product is simple, and the response speed is high, thus the device and method provided by the invention adapt to the rapid, accurate and high-flexible advantages of the quantitative analysis and the mass spectrum analysis.

The invention discloses a chemical ionization mass spectrometer for selectively controlling reaction ions, which comprises an ion source, a reaction ion selecting cavity, a chemical ionization reaction cavity and a mass spectrum detecting cavity, wherein the ion source is used for generating mixed ions; a certain ion in the mixed ions can selectively pass through the reaction ion selecting cavity; two parallel-plate electrodes are arranged in the reaction ion selecting cavity; and the parallel-plate electrodes are connected with a controllable radio-frequency power supply. According to the chemical ionization mass spectrometer provided by the invention, the mixed ions are separated by controlling radio-frequency voltage alternating current components loaded on the parallel-plate electrodes and a direct current component is utilized to select one ion, so as to realize the selective control on the passing of any ion; the ion enters the chemical ionization reaction cavity and is served as the reaction ion for chemical ionization, so as to realize the ionization on a to-be-detected object and detect in the mass spectrum detecting cavity; the chemical ionization mass spectrometer provided by the invention can work under atmosphere pressure and has the characteristics of simplicity in technology and low cost; various reaction ions are selectively controlled and the scope of materials detected by the chemical ionization mass spectrometer is expanded; and the identifying analytical capability of an instrument on unknown samples is increased.

Methods are described for detecting and quantifying occult blood in a biological sample using laser desorption mass spectrometry (LD MS). Biological samples that can be analyzed using various embodiments of the present invention include stool (fecal occult blood, FOB), and any bodily fluid including urine, cerebrospinal fluid and other bodily fluids. If the heme or heme metabolite is bound to protein, the sample is treated with acid before analysis to release the porphyrin. Some of the methods use LD MS with a time of flight analyzer (TOF) to detect and measure unbound heme, other hemoglobin metabolites and other molecules that have a porphyrin-based structure, e.g., bilirubin, biliverdin, protoporphyrin IX, and Zinc protoporphyrin in the biological sample. In other methods, matrix-assisted laser desorption / ionization mass spectrometry (MALDI MS) is used to detect and quantify the individual α- and β-polypeptide chains of hemoglobin.

Provided is a method that achieves both of soft ionization and high ionization efficiency of a substance to be analyzed at each measurement site without impairing a two-dimensional distribution state of the substance to be analyzed in desorption ionization mass spectrometry of a substance to be measured. By applying, to a substance to be analyzed, an ionization assisting reagent including an organic acid including a functional group represented by —(CF2)COOH and having a boiling point of 150° C. or more, and a polyhydric alcohol having a melting point of 20° C. or less and a boiling point of 150° C. or more at normal pressure, the organic acid, which is a component of the ionization assisting reagent, effectively donates a proton to the substance to be analyzed, thereby improving ionization efficiency, and the polyhydric alcohol, which is a component of the ionization assisting reagent, inhibits fragmentation.

A method and apparatus for probing the chemistry of a single droplet are provided. The technique uses a variation of the field-induced droplet ionization (FIDI) method, in which isolated droplets undergo heterogeneous reactions between solution phase analytes and gas-phase species. Following a specified reaction time, the application of a high electric field induces FIDI in the droplet, generating fine jets of highly charged progeny droplets that can then be characterized. Sampling over a range of delay times following exposure of the droplet to gas phase reactants, the spectra yield the temporal variation of reactant and product concentrations. Following the initial mass spectrometry studies, we developed an experiment to explore the parameter space associated with FIDI in an attempt to better understand and control the technique. In an alternative embodiment of the invention switched electric fields are integrated with the technique to allow for time-resolved studies of the droplet distortion, jetting, and charged progeny droplet formation associated with FIDI.

The invention discloses a Nd and Sm separation method applied to Nd isotopc analysis of a thermal ionization mass spectrum. The method comprises the following steps of sample dissolving, in which a sample is dissolved to obtain a 3mol / L of HNO3 medium sample solution; and chemical separation, in which the sample solution is loaded onto an exchange column which is filled with 1.0ml of TODGA levextrel resin, 10ml 3mol / L of HNO3 is used to wash out basic elements including Fe, Mg, Al, K, Na, Cr, Ti and Ba, 10mL 11mol / L HNO3 is used to wash out Ca, 15ml 2.5mol / L HCl is used to wash out interference elements including La, Ce and Pr, 6mL 2mol / L of HCl is used to analyze Nd, and 5mL 0.5mol / L HCl is used to analyze Sm. According to the method, neodymium and samarium can be separated from a geologic sample by one column, Nd and Sm obtained by separation are high in purity and recovery rate, the method is rapid and efficient, and the flow background is low.

The invention discloses an electrospray ionization mass spectrometry combined system used for radioactive substances and a using method for the electrospray ionization mass spectrometry combined system, and aims to solve the problems that when radioactive protective study is performed on actinide elements, a mass spectrometer is required to be integrally sealed in a glove box, the mass spectrometer is large in size, and is connected with various accessories, and the encapsulation difficulty is relatively large. Through analysis and research, the invention discloses a brand-new device which can effectively avoid the potential risk caused by that a sample is dissipated into the air. The electrospray ionization mass spectrometry combined system can be used for a mass spectrometric study on radioactive substances such as the actinide elements, is relatively wide in scope of application, and capable of avoiding the potential risk caused by that the radioactive substances are dissipated into the air to generate radioactive contamination. Meanwhile, reactive substances further can be introduced through a capillary tube connector, so that the electrospray ionization mass spectrometry combined system can be used for researching ion-molecule reaction. The possible problem of an existing device can be effectively solved, the application prospect is relatively good, and the large-scale popularization and application are deserved.

There is disclosed a method of performing laser desorption / ionization mass spectrometry based on ions generated by exposing a sample supported on a substrate to laser light, the sample being to be subjected to spectrum analysis. The method includes the steps of (a) causing a part of the ions to be generated through one of an interaction between the laser light and a surface of the substrate and an interaction between the laser light and an interface between the substrate and the sample; and (b) determining the generated part of the ions to be index ions and identifying a signal to become noise in the laser desorption / ionization mass spectrometry using a signal of the index ions, thereby performing the spectrum analysis without an effect of the noise.

A method and apparatus for conducting mass spectrometry. The mass spectrometry may be accomplished by ion drift-chemical ionization mass spectrometry. One embodiment includes a chemical ionization mass spectrometer comprising an ion drift zone having an ion conductor that transports positive or negative ions. The chemical ionization mass spectrometer further comprises an ion source that produces the positive or negative ions and a mass spectrometer.

Provided is a substrate for mass spectrometry, which enables a detection of a high molecular weight compound to be conducted at a high sensitivity, and can avoid the fragmentation so that there is substantially no obstacle to the analysis of a low molecular weight region. The substrate is a substrate for mass spectrometry for use in laser desorption / ionization mass spectrometry, containing a metal and having a porous structure on a surface thereof, wherein at least one functional group selected from the group consisting of a carboxyl group, a sulfonic group and an ammonium chloride group is covalently bonded to the surface of the substrate.

The invention relates to a method for dating the isotope of limestone Re-Os, and belongs to the technical field of isotope geochronology. The problems that the sampling method is unscientific, the dating samples are blindly selected, the success rate of dating is low, the sample digestion is incomplete and takes a long time, and the impurity interference caused by a dissolution scheme causes the poor accuracy and precision of the limestone Re-Os isotope age results. The method comprises the following steps: collecting a limestone sample and crushing the sample; selecting a limestone dating sample deposited in a reducing environment; pre-digesting the limestone dating sample, and dissolving a pre-digesting solution of the limestone dating sample with a mixed solution of hydrochloric acid and hydrogen peroxide; separating and purifying a dissolution solution Re-Os of the limestone dating sample; performing the Re-Os isotope thermal ionization mass spectrometry; processing the Re-Os isotope data to obtain the final limestone Re-Os isotopic age. The analysis method provided by the invention has the advantages of improving the success rate, accuracy, precision and the operation efficiency of the experimental process of the limestone Re-Os isotope dating.

The invention discloses a method for carrying out online measurement on OH and HO2 free radicals in the atmosphere, particularly relates to implementation of real-time online analysis on the OH and HO2 free radicals in the atmosphere on the basis of high-sensitivity chemical ionization time-of-flight mass spectrometry. A device comprises a free radical sampling device, a chemical ionization sourceand a time-of-flight mass spectrometer; the free radical sampling device implements sampling of the OH and HO2 free radicals; and the chemical ionization source and the time-of-flight mass spectrometer implement measurement of the OH and HO2 free radicals. The main measurement principle is that: by titrating a proper amount of SO2, the OH and HO2 free radicals are all transformed into H2SO4; H2SO4 is ionized into HSO4- ions by NO3- through a chemical ionization method; and finally, by utilizing strength of NO3- and HSO4- ions, which is obtained by measurement, calculation and analysis on real-time concentration of the OH and HO2 free radicals are completed. The instrument and method utilized by the invention have the advantages of high sensitivity, high stability, quick response and the like, meet analysis requirements of free radicals in the atmosphere for real time performance, online performance, dynamic changes and the like, and have wide application prospect in the fields of environmental monitoring and the like.

The invention discloses a low-temperature conversion and measurement method of chlorine isotope in chlorohydrocarbon. The method comprises the steps of A. carrying out oxidation dechlorination treatment on organic matters, namely A-1. injecting pure water into a closed reaction vessel, sequentially feeding ferrous sulfate powder and sodium persulfate solution, shaking up, and standing still; A-2. injecting chlorohydrocarbon into the reaction vessel below the liquid level, then feeding hydrogen peroxide, and rapidly covering an airtight cover of the reaction vessel; A-3. putting the reaction vessel into an ultrasonic apparatus, and carrying out an ultrasonic reaction for 5-12 hours within the temperature range of 50-65 DEG C, wherein the power of the ultrasonic apparatus is 750W or higher; and A-4. putting the reaction vessel onto an ultraviolet analyzer, opening short wave and long wave at the same time, and irradiating for more than 3 hours under the power of 25-35W; B. carrying out inorganic chlorine extraction and purification; and C. carrying out ion exchange preparation and thermal ionization mass spectrometry measurement and correction. According to the low-temperature conversion and measurement method, chlorohydrocarbon can be efficiently converted and purified under the lower temperature condition, and the contrast correction of the constant value of the organic monomer chlorine isotope of the chlorohydrocarbon and international SMOC can be finally realized conveniently and speedily.

The invention belongs to the field of measurement of molybdenum isotope abundance, and more particularly relates to a method for measuring the negative thermal ionization mass spectrometry of molybdenum isotope abundance. The method comprises the three steps of rhenium strip sample coating, temperature raise measurement and data correction. According to the method disclosed by the invention, a negative thermal ionization mass spectrometry measuring method is adopted, a double-rhenium-strip assembly is used, and a SrCl2 solution is used as a cast charge. The method disclosed by the invention solves the technical problems of large sample coating amount, long measuring time and larger relative standard deviation of a measuring result in the prior art. According to the method disclosed by the invention, all index parameters are relatively balanced, thus the technical effects of smaller sample coating amount, short measuring time and smaller relative standard deviation of the measuring result are achieved; and the method is particularly suitable for measuring requirements of a radioactive sample and a biological sample with low cost.

The invention relates to a method for determining boron isotopic composition with static double-receiving method by a positive thermal ionization mass spectrometry, wherein the 309 and 308 ion peaks are statically received simultaneously by two Faraday cups by adjusting the two parameters of FocusQard and DispersionQuad in a focusing optical system, and the determination of high-accuracy boron isotopic composition is finished. The method comprises the following steps: (1) determining the FocusQard and DispersionQuad parameters in ion source optical focusing; (2) determining the two parallel cups and cup parameters of a Faraday receiver; (3) and determining the receiving mass number of the central cup of the Faraday receiver. The method establishes a method for determining boron isotopic composition using double-Faraday-cup static receiving method without changing high-pressure parameter and Faraday cup hardware setting; compared with dynamic peak skip-scanning method, the data acquisition time is greatly shortened, and the sensitivity and inner and outer accuracies of the determination of boron isotopic composition using positive thermal ionization method are improved.

The invention relates to a vehicle-mounted chemical ionization mass spectrometry cruising detection device and method for atmospheric VOCs (volatile organic compounds). The device comprises a navigation vehicle, a chemical ionization mass spectrometer, a shock absorption base, an external sampling head, an internal sampling tube, a GPS, an exhaust pipe, an expanded battery pack, an uninterruptiblepower supply and a data monitoring unit. According to the detection method, atmospheric VOCs are measured through chemical ionization mass spectrometry on a cruising vehicle while the cruising vehicle walks, and a cruising detection result is displayed on an electronic map in real time by fusing mass spectrometry data, GPS position information and the electronic map. The defect that low-concentration large-scale investigation cannot be conducted with conventional technology is overcome, and rapid large-scale investigation of atmospheric VOCs pollution sources is realized.

The invention relates to a sample preparation device for mass spectrometry (MS), and provides an on-line sample preparation device for MALDI-MS. The device comprises two levels of T-shaped orthorhombic microfluidic chips, a matrix reagent injection pump and a target plate. The inlet of a vertical arm of a first level of the T-shaped orthorhombic microfluidic chip is connected with the outlet of an aqueous phase leacheate of a liquid chromatogram, the left cross arm is connected with an oil phase outlet, and the right cross arm is a sample liquid drop outlet. The inlet of a vertical arm of a second level of the T-shaped orthorhombic microfluidic chip is connected with the outlet of the matrix reagent injection pump, the left cross arm is connected with the sample liquid drop outlet of the first level of the T-shaped orthorhombic microfluidic chip, and the right cross arm is the outlet of collected liquid drop samples, namely target liquid drops. The target plate is arranged under the target liquid drop outlet. The on-line sample preparation device for the MALDI-MS is simple and reliable, and analysis of liquid chromatography-mass spectrometry can be worked efficiently.

The invention relates to a novel method for analyzing the isotope ratio of fissile nuclide particles by virtue of FT-TIMS (fission track-thermal ionization mass spectrometry). The method is characterized by comprising the following steps of processing nuclide particles to be detected to prepare an irradiation sample; irradiating the irradiation sample; etching the irradiation sample which is irradiated; performing sample preparation and measurement on the irradiation sample which is etched. Compared with the prior art, the method has the benefits that an operating process is simple, the particles are difficult to lose in an etching process, fission tracks on two detectors can be mutually verified to reduce the missing rate of the particles, and the particles are difficult to lose in a transfer process; furthermore, the recovery rate of the particles to be detected is high, and the recovery efficiency of the method is higher than that of a conventional recovery mode.

Provided is a substrate for mass spectrometry, which enables a detection of a high molecular weight compound to be conducted at a high sensitivity, and can avoid the fragmentation so that there is substantially no obstacle to the analysis of a low molecular weight region. The substrate is a substrate for mass spectrometry for use in laser desorption / ionization mass spectrometry, containing a metal and having a porous structure on a surface thereof, wherein at least one functional group selected from the group consisting of a carboxyl group, a sulfonic group and an ammonium chloride group is covalently bonded to the surface of the substrate.

The invention relates to an electro-spray ionization mass spectrometry device based on a conductive nano-material. The device comprises a sample introducing channel and an electro-spray generation base. The electro-spray generation base comprises a mass spectrometry high-voltage power supply and an electro-spray nozzle. The sample introducing channel is contacted with the electro-spray nozzle; the electro-spray nozzle is made of the conductive nano-material; the mass spectrometry high-voltage power supply is connected with the electro-spray nozzle through a high-voltage line; the front end of the electro-spray nozzle is of an acute-angle tip-end structure; and the front end of the electro-spray nozzle faces to a mass spectrometry entryway. The invention also discloses a method for realizing the electro-spray ionization mass spectrometry through the device. The electro-spray ionization mass spectrometry device has the advantages of not only meeting the requirement of mass spectrometry of a compound dissolved in an electro-spray-friendly solvent, but also meeting the requirement of mass spectrometry of compounds dissolved in the electro-spray-friendly solvent and an electro-spray-unfriendly solvent, such as a low polar solvent. The method is simple; the cost is low; adjustable parameters are few, ionization efficiency is high; introduction of extra auxiliary solvents is not need; and matrix interference of the extra solvents does not exist.

The invention relates to the technical field of mass spectrometry, in particular to an ion transmission system. The ion transmission system comprises an octopole rod device and a power supply controller, wherein the octopole rod device comprises two insulating supports and eight conical rods, wherein the eight conical rods are arranged at equal intervals to form a conical form; two ends of each of the eight conical rods are fixed through the insulating supports and are used for being connected to a mass spectrometer inlet and a mass analyzer inlet respectively; four spaced conical rods are connected through a guide wire to form an electrode; the eight conical rods form two electrodes in all; radio-frequency voltage which is equal in amplitude value, but opposite in phase is applied to the two electrodes through the power supply controller respectively; and meanwhile, DC voltage which is equal in polarity and numerical value is superposed on the two electrodes respectively. The ion transmission system can be applied to a chemical ionization mass spectrometry; ion cleavage caused by a strong electric field can be prevented to the minimum extent; and the focusing capability of ions is effectively improved. The overall system is relatively easy to manufacture and low in cost.