CN115116819A - Electrospray extraction ionization source - Google Patents

Electrospray extraction ionization source Download PDF

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Publication number
CN115116819A
CN115116819A CN202210786530.8A CN202210786530A CN115116819A CN 115116819 A CN115116819 A CN 115116819A CN 202210786530 A CN202210786530 A CN 202210786530A CN 115116819 A CN115116819 A CN 115116819A
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CN
China
Prior art keywords
sample
pipeline
mass spectrum
sample inlet
ionization source
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Pending
Application number
CN202210786530.8A
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Chinese (zh)
Inventor
李雪
方明亮
张柯达
还涛
张玮
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Guangdong Zhipu Life Technology Co ltd
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Guangdong Zhipu Life Technology Co ltd
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Priority to CN202210786530.8A priority Critical patent/CN115116819A/en
Publication of CN115116819A publication Critical patent/CN115116819A/en
Pending legal-status Critical Current

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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00Particle spectrometers or separator tubes
    • H01J49/02Details
    • H01J49/10Ion sources; Ion guns
    • H01J49/16Ion sources; Ion guns using surface ionisation, e.g. field-, thermionic- or photo-emission
    • H01J49/165Electrospray ionisation
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00Particle spectrometers or separator tubes
    • H01J49/02Details
    • H01J49/04Arrangements for introducing or extracting samples to be analysed, e.g. vacuum locks; Arrangements for external adjustment of electron- or ion-optical components
    • H01J49/0422Arrangements for introducing or extracting samples to be analysed, e.g. vacuum locks; Arrangements for external adjustment of electron- or ion-optical components for gaseous samples

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  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)

Abstract

The invention discloses an electrospray extraction ionization source, which relates to the technical field of chemical analysis and comprises a sample feeding pipeline, an aerodynamic lens assembly, a capillary tube, an electrode assembly and a mass spectrometer, wherein one end of the sample feeding pipeline is provided with an aerosol sample inlet, the other end of the sample feeding pipeline is provided with an air outlet, and the pipe wall of the sample feeding pipeline is provided with a sample ion outlet; one end of the capillary extending into the sample introduction pipeline is positioned between the aerodynamic lens assembly and the sample ion outlet; the electrode assembly comprises a direct current power supply and an electrode plate fixedly arranged in the sample injection pipeline, and the electrode plate is electrically connected with the direct current power supply; the mass spectrometer is provided with a mass spectrum sample inlet which is connected and communicated with the sample ion outlet. The electrospray extraction ionization source provided by the invention can avoid collision of gas-phase ions and aerosol particles, and can prevent the aerosol particles from entering the mass spectrometer.

Description

Electrospray extraction ionization source
Technical Field
The invention relates to the technical field of chemical analysis, in particular to an electrospray extraction ionization source.
Background
The atmospheric aerosol has very complicated organic chemical composition, and the rapid analysis of organic components in the atmospheric aerosol, particularly the on-line analysis of low-content organic matters, is a difficult problem in the field of atmospheric chemical analysis. Electrospray ionization (EESI) is a new type of mass spectrometry ionization technology derived based on Electrospray ionization (ESI). The EESI source usually adopts a self-suction sample introduction mode, namely air flow in the atmosphere is sucked into a mass spectrum sample introduction port through the vacuum self-suction capacity in a mass spectrometer, then nanoliter spray introduced at a certain angle is adopted to collide with the sample introduction air flow containing aerosol, liquid drops generated by one-time spray immediately react with aerosol particles, and organic matter ions to be analyzed are formed. And finally, further sucking the airflow with the aerosol particles and the gas-phase ions into the mass spectrum, wherein redundant gas can be directly pumped out by a vacuum pump, and the gas-phase ions are finally detected by a mass analyzer so as to form a mass spectrum.
The existing EESI source has the advantages that the airflow direction is coaxial with the direction of a mass spectrum sample inlet, so aerosol particles can be sucked into a mass spectrum together when the mass spectrum sucks ions and remain in the mass spectrum, the aerosol deposits in a mass spectrum cavity to greatly pollute the inside of the mass spectrum after long-term continuous use, and the maintenance frequency of an instrument is improved; meanwhile, in the process that gas-phase ions formed by ionization of the aerosol are absorbed into the mass spectrum sample inlet, the gas-phase ions collide with aerosol substances still mixed in the instrument, so that ion loss is caused, and the sensitivity of the instrument is reduced; the EESI adopting the vacuum self-suction mode has the problems of small sample introduction flow and incapability of adjusting the sample introduction flow, so that the detection capability of low-content organic matters in the environment with small particle concentration is limited.
Disclosure of Invention
The invention aims to provide an electrospray extraction ionization source, which is used for solving the problems in the prior art, avoiding collision between gas-phase ions and aerosol particles and avoiding the aerosol particles from entering a mass spectrometer.
In order to achieve the purpose, the invention provides the following scheme:
the invention provides an electrospray extraction ionization source which comprises a sample introduction pipeline, an aerodynamic lens assembly, a capillary tube, an electrode assembly and a mass spectrometer, wherein the aerodynamic lens assembly is arranged in the sample introduction pipeline and is positioned between an aerosol sample inlet and a sample ion outlet; the aerodynamic lens assembly can focus the aerosol sample entering the sample feeding pipeline; the capillary is used for introducing nanoliter spray into the sample introduction pipeline, and one end of the capillary extending into the sample introduction pipeline is positioned between the aerodynamic lens assembly and the sample ion outlet; the electrode assembly comprises a direct current power supply and an electrode plate fixedly arranged in the sample injection pipeline, and the electrode plate is electrically connected with the direct current power supply; the mass spectrometer is provided with a mass spectrum sample inlet, the mass spectrum sample inlet is connected and communicated with the sample ion outlet, and gas-phase ions in the gas mixture can enter the mass spectrometer from the sample ion outlet through the mass spectrum sample inlet under the action of electric field force generated by the electrode slice.
Preferably, the aerodynamic lens assembly comprises a plurality of aerodynamic lenses which are positioned inside the sample introduction pipeline and are sequentially arranged at intervals.
Preferably, the capillary and the sample introduction pipeline are arranged at an angle, and the direction of the speed component of the nano-liter spray introduced into the sample introduction pipeline along the axis direction of the sample introduction pipeline is the same as the movement direction of the aerosol sample.
Preferably, the air exhaust device is further included, and the air exhaust device is connected and communicated with the air outlet.
Preferably, the air extracting device comprises an air extracting fan and an air extracting pipe, one end of the air extracting pipe is connected and communicated with the air outlet, and the other end of the air extracting pipe is connected and communicated with the air extracting fan.
Preferably, the mass spectrometer is provided with a mass spectrum sample inlet pipe, the end part of the mass spectrum sample inlet pipe is provided with the mass spectrum sample inlet, the mass spectrum sample inlet pipe passes through the mass spectrum sample inlet and is connected and communicated with the sample ion outlet, and the mass spectrum sample inlet pipe is perpendicular to the sample inlet pipeline.
Compared with the prior art, the invention has the following technical effects:
in the electrospray extraction ionization source provided by the invention, an aerosol sample can enter a sample inlet pipeline through an aerosol sample inlet, and is focused by an aerodynamic lens assembly to collide with nanoliter spray introduced by a capillary tube, the aerosol sample is ionized after colliding with the nanoliter spray to form gas-phase ions, when a gas mixture passes through an electrode assembly, the gas-phase ions can enter a mass spectrometer through a sample ion outlet under the action of electric field force generated by an electrode plate to complete mass spectrum detection and analysis, the rest gas mixture can be discharged from the sample inlet pipeline through a gas outlet, the gas-phase ions formed by ionization are shunted from the gas mixture, the gas-phase ions can be prevented from colliding with aerosol particles or other gas molecules, the loss of the gas-phase ions is avoided, the detection sensitivity is improved, and only the gas-phase ions enter the mass spectrometer, and other gas mixtures are removed, so that aerosol particles can be prevented from being deposited inside the mass spectrometer, and the maintenance period of the instrument is greatly shortened.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a schematic structural diagram of an electrospray extraction ionization source provided by the present invention;
in the figure: 100-electrospray extraction ionization source; 1-a sample introduction pipeline; 11-aerosol sample inlet; 12-gas outlet; 13-sample ion outlet; 2-an aerodynamic lens assembly; 3-a capillary tube; 4-an electrode assembly; 41-electrode slice; 42-a direct current power supply; 5-a mass spectrometer; 51-mass spectrum sampling tube; 52-mass spectrum sample inlet; 6-air extraction device.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to provide an electrospray extraction ionization source, which is used for solving the problems in the prior art, avoiding collision between gas-phase ions and aerosol particles and avoiding the aerosol particles from entering a mass spectrometer.
In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, the present invention is described in detail with reference to the accompanying drawings and the detailed description thereof.
The invention provides an electrospray extraction ionization source 100, as shown in fig. 1, in this embodiment, the electrospray extraction ionization source comprises a sample introduction pipeline 1, an aerodynamic lens assembly 2 arranged inside the sample introduction pipeline 1 and positioned between an aerosol sample inlet 11 and a sample ion outlet 13, a capillary tube 3 capable of penetrating through the tube wall of the sample introduction pipeline 1 and extending into the sample introduction pipeline 1, an electrode assembly 4 and a mass spectrometer 5, wherein one end of the sample introduction pipeline 1 is provided with the aerosol sample inlet 11, the other end of the sample introduction pipeline 1 is provided with an air outlet 12, and the tube wall of the sample introduction pipeline 1 is provided with the sample ion outlet 13; the aerodynamic lens assembly 2 can focus the aerosol sample entering the sample introduction pipeline 1; the capillary 3 is used for introducing nanoliter spray into the sample introduction pipeline 1, and one end of the capillary 3 extending into the sample introduction pipeline 1 is positioned between the aerodynamic lens assembly 2 and the sample ion outlet 13; the electrode assembly 4 comprises a direct current power supply 42 and an electrode plate 41 fixedly arranged in the sample introduction pipeline 1, and the electrode plate 41 is electrically connected with the direct current power supply 42; the mass spectrometer 5 is provided with a mass spectrum sample inlet 52, the mass spectrum sample inlet 52 is connected and communicated with the sample ion outlet 13, and gas-phase ions in the gas mixture can enter the mass spectrometer 5 from the sample ion outlet 13 through the mass spectrum sample inlet 52 under the action of an electric field force generated by the electrode plate 41.
An aerosol sample enters the sample inlet pipeline 1 under the action of double air flow suction of an air extractor 6 and a mass spectrum sample inlet 52, then passes through an aerodynamic lens assembly 2 for focusing, the aerosol particles are finally focused to the axial position of the sample inlet pipeline 1 to form a narrow collimated particle beam, the beam width is about 1mm, and then has collision reaction with nano-liter spray introduced by a capillary tube 3, organic components in the aerosol particles are vaporized and ionized under the extraction action of liquid drops to form gas-phase ions, when a gas mixture passes through an electrode assembly 4, the gas-phase ions can deviate from the flow trajectory of the primary air flow under the action of electric field force generated by an electrode plate 41, simultaneously, under the action of suction generated at the mass spectrum sample inlet 52 of a mass spectrometer 5, the sample ions can enter the mass spectrometer 5, and the gas-phase ions entering the mass spectrum are detected under the action of an extraction lens and a high-resolution mass analyzer, form high-quality mass spectrum and be used for subsequent mass spectrometry, and other gas mixtures then can be taken out by air exhaust 6 through gas outlet 12, the gaseous phase ion that the ionization formed shunts from gas mixture, can prevent gaseous phase ion and aerosol particulate matter or other gas molecules from colliding, avoid gaseous phase ion's loss, the sensitivity of mass spectrometry detection has been improved, and simultaneously, only gaseous phase ion gets into in mass spectrograph 5, other gas mixtures then are got rid of, can avoid aerosol particulate matter at the inside deposit of mass spectrograph 5, the maintenance cycle of instrument has been reduced by a wide margin.
The electrode plate 41 can be arranged opposite to the sample ion outlet 13 and used for generating electric field force to push gas-phase ions to the mass spectrum sample inlet 52; meanwhile, the electrode plate 41 may also be disposed at the position of the sample ion outlet 13 for generating a suction force to suck the gas phase ions into the mass spectrum sample inlet 52.
The aerodynamic lens assembly 2 includes a plurality of aerodynamic lenses that are located sample introduction pipeline 1 inside and set up at interval in proper order, and the focus hole piece quantity in the aerodynamic lens is 1 at least, can be according to the particle size range adjustment size and the quantity of total kind of flow and particulate matter of advancing, can also be according to the requirement of total flow simultaneously, and the structure of nimble focus hole piece that changes has improved the flexibility of experiment.
Capillary 3 and appearance pipeline 1 angulation setting, let in to the direction of the velocity component of 1 axis direction of appearance pipeline 1 inside nanoliter spraying along the appearance pipeline 1 axis direction the same with aerosol sample motion direction by capillary 3, capillary 3 can be provided with a plurality ofly, uses a plurality of capillaries 3 to let in nanoliter spraying, can improve the ionization efficiency of aerosol sample.
In the alternative provided by the present invention, preferably, the electrospray extraction ionization source 100 further includes an air extractor 6, the air extractor 6 is connected and communicated with the air outlet 12, and the air extractor 6 is configured to perform additional air extraction, so that the sample injection flow rate entering the sample injection pipeline 1 is greatly increased, and the total amount of the analytes entering the system in unit time is effectively increased.
The air extracting device 6 comprises an air extracting fan and an air extracting pipe, one end of the air extracting pipe is connected and communicated with the air outlet 12, and the other end of the air extracting pipe is connected and communicated with the air extracting fan.
The mass spectrometer 5 is provided with a mass spectrum sample inlet pipe 51, a mass spectrum sample inlet 52 is formed in the end part of the mass spectrum sample inlet pipe 51, the mass spectrum sample inlet pipe 51 is connected and communicated with the sample ion outlet 13 through the mass spectrum sample inlet 52, and the mass spectrum sample inlet pipe 51 is perpendicular to the sample inlet pipeline 1.
The principle and the implementation mode of the invention are explained by applying a specific example, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims (6)

1. An electrospray extraction ionization source, comprising: the method comprises the following steps:
the device comprises a sample feeding pipeline, a gas sampling pipeline and a gas outlet pipeline, wherein one end of the sample feeding pipeline is provided with an aerosol sample inlet, the other end of the sample feeding pipeline is provided with a gas outlet, and a sample ion outlet is formed in the pipe wall of the sample feeding pipeline;
the aerodynamic lens assembly is arranged in the sample introduction pipeline and positioned between the aerosol sample inlet and the sample ion outlet, and can focus the aerosol sample entering the sample introduction pipeline;
the capillary can penetrate through the tube wall of the sample injection pipeline and extend into the sample injection pipeline, the capillary is used for introducing nanoliter spray into the sample injection pipeline, and one end, extending into the sample injection pipeline, of the capillary is located between the aerodynamic lens assembly and the sample ion outlet;
the electrode assembly comprises a direct-current power supply and an electrode plate fixedly arranged in the sample injection pipeline, and the electrode plate is electrically connected with the direct-current power supply;
and the mass spectrometer is provided with a mass spectrum sample inlet, the mass spectrum sample inlet is connected and communicated with the sample ion outlet, and gas-phase ions in the gas mixture can enter the mass spectrometer from the sample ion outlet through the mass spectrum sample inlet under the action of electric field force generated by the electrode slice.
2. An electrospray extraction ionization source according to claim 1, characterized by: the aerodynamic lens assembly comprises a plurality of aerodynamic lenses which are positioned in the sample feeding pipeline and are sequentially arranged at intervals.
3. An electrospray extraction ionization source according to claim 1, characterized by: the capillary with advance kind pipeline angulation setting, by the capillary lets in to advance the inside nanoliter spraying of kind pipeline is followed the direction of the velocity component of advance kind pipeline axis direction is the same with aerosol sample direction of motion.
4. An electrospray extraction ionization source according to claim 1, characterized by: the air exhaust device is connected and communicated with the air outlet.
5. An electrospray extraction ionization source according to claim 4, characterized by: the air extracting device comprises an air extracting fan and an air extracting pipe, one end of the air extracting pipe is connected and communicated with the air outlet, and the other end of the air extracting pipe is connected and communicated with the air extracting fan.
6. An electrospray extraction ionization source according to claim 1, characterized by: the mass spectrometer is provided with a mass spectrum sample inlet pipe, the end part of the mass spectrum sample inlet pipe is provided with the mass spectrum sample inlet, the mass spectrum sample inlet pipe passes through the mass spectrum sample inlet and is connected and communicated with the sample ion outlet, and the mass spectrum sample inlet pipe is perpendicular to the sample inlet pipeline.
CN202210786530.8A 2022-07-04 2022-07-04 Electrospray extraction ionization source Pending CN115116819A (en)

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CN202210786530.8A CN115116819A (en) 2022-07-04 2022-07-04 Electrospray extraction ionization source

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Application Number Priority Date Filing Date Title
CN202210786530.8A CN115116819A (en) 2022-07-04 2022-07-04 Electrospray extraction ionization source

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115938909A (en) * 2022-11-22 2023-04-07 广东智普生命科技有限公司 Laser-coupled electrospray extraction ionization source and analysis system

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Publication number Priority date Publication date Assignee Title
WO2006060130A2 (en) * 2004-11-09 2006-06-08 E.I. Dupont De Nemours And Company Ion source for a mass spectrometer
CN101281165A (en) * 2008-05-15 2008-10-08 复旦大学 Method and apparatus for ionizing mass spectrographic analysis sample
CN102854240A (en) * 2011-06-28 2013-01-02 中国科学院生态环境研究中心 Ion trap mass spectrometer for organic aerosol ionized by vacuum ultraviolet light
CN104792854A (en) * 2015-03-31 2015-07-22 广州禾信分析仪器有限公司 System and method for real-time and on-line rapid mass spectrometry analysis on chemical compositions of sub-micron aerosol
CN108630517A (en) * 2018-05-10 2018-10-09 中国科学院大气物理研究所 The plasma ionization method and device of Atmospheric particulates
CN112614773A (en) * 2020-12-28 2021-04-06 广州禾信仪器股份有限公司 Mass spectrum ion source sampling device
CN113871285A (en) * 2020-06-30 2021-12-31 广州禾信仪器股份有限公司 Aerosol mass spectrum sampling device with wide particle size range and aerosol mass spectrometer

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006060130A2 (en) * 2004-11-09 2006-06-08 E.I. Dupont De Nemours And Company Ion source for a mass spectrometer
CN101281165A (en) * 2008-05-15 2008-10-08 复旦大学 Method and apparatus for ionizing mass spectrographic analysis sample
CN102854240A (en) * 2011-06-28 2013-01-02 中国科学院生态环境研究中心 Ion trap mass spectrometer for organic aerosol ionized by vacuum ultraviolet light
CN104792854A (en) * 2015-03-31 2015-07-22 广州禾信分析仪器有限公司 System and method for real-time and on-line rapid mass spectrometry analysis on chemical compositions of sub-micron aerosol
CN108630517A (en) * 2018-05-10 2018-10-09 中国科学院大气物理研究所 The plasma ionization method and device of Atmospheric particulates
CN113871285A (en) * 2020-06-30 2021-12-31 广州禾信仪器股份有限公司 Aerosol mass spectrum sampling device with wide particle size range and aerosol mass spectrometer
CN112614773A (en) * 2020-12-28 2021-04-06 广州禾信仪器股份有限公司 Mass spectrum ion source sampling device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115938909A (en) * 2022-11-22 2023-04-07 广东智普生命科技有限公司 Laser-coupled electrospray extraction ionization source and analysis system
CN115938909B (en) * 2022-11-22 2024-04-19 广东智普生命科技有限公司 Laser-coupled electrospray extraction ionization source and analysis system

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