CN116297803A - Double-spray micro-sample detection ionization source - Google Patents
Double-spray micro-sample detection ionization source Download PDFInfo
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- CN116297803A CN116297803A CN202211612523.2A CN202211612523A CN116297803A CN 116297803 A CN116297803 A CN 116297803A CN 202211612523 A CN202211612523 A CN 202211612523A CN 116297803 A CN116297803 A CN 116297803A
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- electrospray ion
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- 239000007921 spray Substances 0.000 title claims abstract description 46
- 238000001514 detection method Methods 0.000 title claims abstract description 16
- 238000001212 derivatisation Methods 0.000 claims abstract description 58
- 239000003153 chemical reaction reagent Substances 0.000 claims abstract description 54
- 238000001819 mass spectrum Methods 0.000 claims abstract description 18
- 238000002347 injection Methods 0.000 claims abstract description 12
- 239000007924 injection Substances 0.000 claims abstract description 12
- 239000007788 liquid Substances 0.000 claims abstract description 11
- 230000001105 regulatory effect Effects 0.000 claims description 24
- 230000009977 dual effect Effects 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 6
- 239000003795 chemical substances by application Substances 0.000 claims description 4
- 238000006243 chemical reaction Methods 0.000 abstract description 5
- 150000001875 compounds Chemical class 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 230000033001 locomotion Effects 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 238000000065 atmospheric pressure chemical ionisation Methods 0.000 description 1
- 238000000451 chemical ionisation Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007787 electrohydrodynamic spraying Methods 0.000 description 1
- 238000000752 ionisation method Methods 0.000 description 1
- 239000002207 metabolite Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000005211 surface analysis Methods 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J49/00—Particle spectrometers or separator tubes
- H01J49/02—Details
- H01J49/10—Ion sources; Ion guns
- H01J49/16—Ion sources; Ion guns using surface ionisation, e.g. field-, thermionic- or photo-emission
- H01J49/165—Electrospray ionisation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/62—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating the ionisation of gases, e.g. aerosols; by investigating electric discharges, e.g. emission of cathode
- G01N27/64—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating the ionisation of gases, e.g. aerosols; by investigating electric discharges, e.g. emission of cathode using wave or particle radiation to ionise a gas, e.g. in an ionisation chamber
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- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
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- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
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- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
Abstract
The invention provides a double-spray trace sample detection ionization source. The invention comprises a spray ionization source supporting housing, wherein the spray ionization source supporting housing is connected with a mass spectrum detector, a derivatization reagent electrospray ion source and a nano-liter electrospray ion source are arranged on the spray ionization source supporting housing, the derivatization reagent electrospray ion source is used for ionizing a derivatization reagent into liquid drops in an electrospray mode, the nano-liter electrospray ion source is used for ionizing a sample to be tested, the sample is reacted with the derivatization liquid drops and enters the mass spectrum detector for full reaction, a preset inclination angle exists between a derivatization reagent electrospray needle and a sample inlet of the mass spectrum detector, and the derivatization reagent electrospray ion source and the nano-liter electrospray ion source are both provided with three-axis position regulators for self position adjustment. The invention provides an integrated device for observing ionization efficiency, which can realize cross sample injection of two paths of electrospray ion sources.
Description
Technical Field
The invention relates to the technical field of cell biology, in particular to a double-spray micro-sample detection ionization source.
Background
The application number 201420581801.7 discloses a sealing structure for connection between a discharge needle and a tail part. The function of this patent is to surface analyze an atmospheric pressure chemical ionization source. However, the device cannot realize mutual extraction of two electrosprays in the ionization process, and cannot improve the derivatization capability of the metabolite. The application number 201410528902.2 discloses an adjusting device for a surface analysis normal pressure chemical ionization source, which can accurately and quantitatively adjust a plurality of parameters such as the angle between the spray head position of the ion source and a mass spectrum sample inlet, the distance of the ion source and the like, so that the chemical analysis ionization source is more suitable for various environments. But this patent lacks precise regulation of the voltage flow rate of the ionization source, etc., which greatly affects the subsequent ionization effect. The application number 201811092981.1 of the closed electrospray extraction ionization source device adopts a closed structure, an ion source is positioned in a cavity of a sealed cavity, and the rotary motion of the ion source or a gas sample injection assembly can not cause the translation of the tip of the ion source or the head of the gas sample injection assembly, so that the large-angle adjustment of the ion source or the gas sample injection assembly is realized. But this patent lacks the function of adjusting the position of the ionization source. In view of the technical shortcomings of the above-mentioned patents, regarding the structure of dual spray in ionization sources, many patents cannot realize multiple ways of adjusting the positions and structures of two ionization sources at the same time. It is not possible to provide an integrated device for observing the ionization efficiency during use.
Disclosure of Invention
According to the technical problem, a dual-spray micro-sample detection ionization source is provided. The invention adopts the following technical means:
the utility model provides a dual spray trace sample detects ionization source, includes spray ionization source support dustcoat, spray ionization source supports the dustcoat and links to each other with mass spectrum detector, install derivatization reagent electrospray ion source and nano liter electrospray ion source on the spray ionization source supports the dustcoat, derivatization reagent electrospray ion source is used for ionizing derivatization reagent into the liquid droplet through the mode of electrospray, nano liter electrospray ion source is used for the sample ionization that awaits measuring, through with derivatization liquid droplet reaction, enter into mass spectrum detector and carry out abundant reaction, derivatization reagent electrospray needle and mass spectrum detector sample inlet have a preset inclined angle, derivatization reagent electrospray ion source and nano liter electrospray ion source all possess self position adjustment's triaxial position regulator.
Further, the derivatization reagent electrospray ion source has a constant inclination angle of 40-60 degrees.
Further, the ionization of the derivatizing agent is accelerated by a sheath flow gas based on current carrying in the process of injecting the derivatizing agent, and the flow rate of the sheath flow gas is 0.5-2L/min.
Further, the three-axis position regulator of the derivatization reagent electrospray ion source comprises an X-axis regulating mechanism, a Y-axis regulating mechanism and a Z-axis regulating mechanism, the height difference between the derivatization reagent electrospray ion source and the sample inlet of the mass spectrum detector is regulated based on the Z-axis regulating mechanism, after the inclination angle of the derivatization reagent electrospray ion source is confirmed, the position is regulated along the established inclination angle through the X-axis regulating mechanism and the Y-axis regulating mechanism, and the regulating precision of the position distance is +/-10 um.
Further, the sample to be measured is fixed on a three-dimensional adjusting support frame of the nano-liter electrospray ion source, the support frame is fixed on a linear slide rail, a first positioning part and a second positioning part are arranged on the slide rail, the first positioning part is used for determining the optimal position of sample introduction of the sample to be measured, and the second positioning part is used for calibrating and changing the optimal position of a spray needle for sample introduction electrospray.
Further, the electric spray of the derivatization reagent and the electric spray of the sample to be tested are driven in an external high-voltage mode, wherein the electric spray of the derivatization reagent is direct-current high voltage, and the electric spray of the sample to be tested is alternating-current square wave high voltage. The two sets of high-voltage systems are respectively isolated in power supply potential, the applied direct-current high voltage and voltage output are adjustable, the range of the voltage output is 0.5-3kV, the range of the alternating-current high voltage adjustment is 0.5-4kV, and the frequency is 10-1000Hz.
Further, the output ends of the derivatization reagent electrospray ion source and the nanoliter electrospray ion source are respectively provided with an image acquisition device, and the optimal value of the ion flow signal after the position adjustment of the derivatization reagent electrospray ion source and the nanoliter electrospray ion source is confirmed based on the two-path spray plume conditions acquired by the image acquisition devices.
The invention provides a double-spray trace sample detection ionization source, wherein one path of the double-spray trace sample detection ionization source is used as electrospraying of a sample to be detected, and the double-spray trace sample detection ionization source has the characteristics of high ionization efficiency and low sample injection quantity. The other path is derivatization reagent electrospray, which aims to form small liquid drops by generating liquid drop electrospray in the sample analysis process, and react with certain compounds in the sample to be detected as derivatization reagent, and react with the sample to be detected by on-line derivatization, so that the detection sensitivity of the specific compounds is improved. The invention can realize the cross sample injection of two paths of electrospray ion sources. One path of sample is parallel to the position of the sample inlet. The invention can rapidly move the sliding rail by utilizing the sliding rail connection mode. Meanwhile, the two positions of sample injection and needle replacement are extremely accurate.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings may be obtained according to the drawings without inventive effort to a person skilled in the art.
FIG. 1 is a schematic diagram of the overall structure of the present invention.
Fig. 2 is a top view of the present invention.
Fig. 3 is a top cross-sectional view of the present invention.
Fig. 4 is a schematic view of the sliding rail movement of the present invention.
In the figure: 001: a high resolution mass spectrum detector; 002: derivatizing agent electrospray needle; 003: electrospray needle of sample to be measured; 004: an electrode sheet; 005: an electrospray needle fastener of a sample to be tested; 006: an electrospray needle fixing piece of a sample to be tested; 007: connecting rod of electrospray needle of sample to be measured; 008: a slide rail support; 009: an orthogonal triaxial adjuster; 010: a slider fastener; 011: moving the slide block; 012: a linear slide rail; 013: a slider positioning member; 014: the dual spray ionization source supports the cover; 015: spray shape observation camera; 016: a reagent electrospray X-direction adjusting member; 017: a reagent electrospray diagonal direction adjusting member; 018: a reagent electrospray Y-direction adjusting member; 019: a sample electrospray Y-direction adjusting member; 020: a sample electrospray Z-direction adjusting member; 021: sample electrospray X-direction adjuster.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
As shown in fig. 1 to 4, the embodiment of the invention discloses a dual-spray micro-sample detection ionization source, which comprises a spray ionization source support housing, wherein the spray ionization source support housing is connected with a mass spectrum detector 001, a derivatization reagent electrospray ion source 002 and a nano-liter electrospray ion source 003 are arranged on the spray ionization source support housing 014, and the derivatization reagent electrospray ion source is used for ionizing the derivatization reagent into liquid drops in an electrospray manner, so that the reaction efficiency of the liquid drops can be sufficiently improved; the nano-liter electrospray ion source is used for ionizing a sample to be detected, the sample to be detected is reacted with the derivatization liquid drops, the sample enters the mass spectrum detector to fully react, a preset inclined angle exists between the derivatization reagent electrospray needle and a sample inlet of the mass spectrum detector, the derivatization reagent electrospray ion source and the nano-liter electrospray ion source are both provided with three-axis position regulators with self-position regulation, and after the position is determined, the sample to be detected is fixed through the electrospray needle fastener 005 of the sample to be detected and the electrospray needle fixing piece 006 of the sample to be detected.
The angle of inclination of the derivatization reagent electrospray ion source is a constant value of 40-60 degrees.
The injection process of the derivatization reagent is based on the ionization of the current-carrying sheath flow gas, and the flow speed of the sheath flow gas is 0.5-2L/min.
The three-axis position regulator 009 of the derivatization reagent electrospray ion source comprises an X-axis regulating mechanism 016, a Y-axis regulating mechanism 018 and a Z-axis regulating mechanism (reagent electrospray oblique direction regulating piece 017), after the inclination angle of the derivatization reagent electrospray ion source is confirmed based on the height difference between the derivatization reagent electrospray ion source and a sample inlet of a mass spectrum detector regulated by the Z-axis regulating mechanism, the angle of the spray needle is relatively fixed, and under the specific angle, the position regulation is carried out along the established inclination angle through the X-axis regulating mechanism and the Y-axis regulating mechanism, and the regulation precision of the position distance is +/-10 um. When the position is adjusted, the spray needle is slightly far away from the sample inlet of the mass spectrum, so that the derivatization reagent is prevented from influencing the spray flow of the sample to be measured.
The sample to be measured is fixed on a three-dimensional adjusting support frame of a nano-liter electrospray ion source, the support frame is fixed on a linear slide rail 012, the slide rail 012 is connected with the support frame through a slide rail support member 008, a slide block positioning member 013 is arranged on the slide rail, the sample to be measured specifically comprises a first positioning part and a second positioning part, the first positioning part is used for determining the optimal position of sample introduction of the sample to be measured, the ionization efficiency at the position is highest, and meanwhile, the efficiency of the sample introduction reaction with the derivatization electrospray is also optimal. The second positioning part is used for calibrating and changing the optimal position of the injection needle for the injection electrospray. The length of the movement in the sliding rail is selected to be 100-200mm from one end to the field end, and the long distance can cause deformation of the eating support in the moving process.
In this embodiment, the entire sliding system is a single body, which includes: the sample electrospray component to be tested, a three-dimensional adjusting piece, a movable slider 011 and a slider fastener 010 at the bottom end thereof. The three-dimensional adjusting piece comprises a sample electrospray Y-direction adjusting piece 019, a sample electrospray Z-direction adjusting piece 020 and a sample electrospray X-direction adjusting piece 021, wherein the fastening piece of a sliding block is very critical, and the working mode is that the position of a movable sliding block and the position of a linear sliding rail are kept relatively fixed through a jackscrew, and particularly, a sample electrospray needle connecting rod 007 to be measured of a sample to be measured is fixed at the position of an ionization source, so that the position of the electrospray needle of the sample to be measured is fixed; and when the spray needle moves to the tail end, the sliding system is fixed in position, so that the spray needle can be conveniently replaced.
The method comprises the steps of driving the electrospray of the derivatization reagent and the electrospray of the sample to be tested in an external high-voltage mode, wherein the electrospray of the derivatization reagent is direct-current high voltage, and the electrospray of the sample to be tested is alternating-current square wave high voltage. The two sets of high-voltage systems are respectively isolated in power supply potential, the voltage output is adjustable through the direct-current high voltage applied by the electrode plate 004, the range of the voltage output is 0.5-3kV, the range of the alternating-current high voltage adjustment is 0.5-4kV, and the frequency is 10-1000Hz.
The image acquisition devices 015, in particular to external cameras, are arranged at the output ends of the derivatization reagent electrospray ion source and the nanoliter electrospray ion source, and after the position adjustment of the derivatization reagent electrospray ion source and the nanoliter electrospray ion source is confirmed based on the two paths of spray plume conditions acquired by the image acquisition devices, the relative positions of the two sets of ionization sources are respectively adjusted, and the optimal value of an ion flow signal is obtained.
The adjusting step is to ensure that the whole ion flow signal of the sample to be measured is strong. And then adjusting the electrospray of the derivatization reagent to observe the increase of the signal intensity of the target compound after derivatization. After two approximate positions are determined, the two paths of fine adjustment enable the overall ion flow signal to be strong and the specific target compound signal to be strong.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (7)
1. The utility model provides a dual spray trace sample detects ionization source, its characterized in that includes spray ionization source support dustcoat, spray ionization source supports the dustcoat and links to each other with mass spectrum detector, install derivatization reagent electrospray ion source and nano liter electrospray ion source on the spray ionization source supports the dustcoat, derivatization reagent electrospray ion source is used for ionizing derivatization reagent into the liquid droplet through the mode of electrospray, nano liter electrospray ion source is used for with the sample ionization that awaits measuring, through reacting with derivatization liquid droplet, enter into mass spectrum detector and fully react, derivatization reagent electrospray needle and mass spectrum detector sample inlet have a preset inclination angle, derivatization reagent electrospray ion source and nano liter electrospray ion source all possess self position adjustment's triaxial position regulator.
2. The dual spray micro-sample detection ionization source of claim 1 wherein said derivatizing agent electrospray ion source is tilted at a constant angle of 40-60 degrees.
3. The dual spray trace sample detection ionization source according to claim 1, wherein the derivatization reagent injection process is based on ionization of a current carrying sheath flow gas to accelerate ionization of the derivatization reagent, the sheath flow gas having a flow rate of 0.5-2L/min.
4. The dual spray trace sample detection ionization source according to claim 1 or 2, wherein the three-axis position regulator of the derivatization reagent electrospray ion source comprises an X-axis regulating mechanism, a Y-axis regulating mechanism and a Z-axis regulating mechanism, wherein the position regulation is performed along a predetermined inclination angle by the X-axis regulating mechanism and the Y-axis regulating mechanism after confirming the inclination angle of the derivatization reagent electrospray ion source based on the height difference between the derivatization reagent electrospray ion source and the sample inlet of the mass spectrum detector regulated by the Z-axis regulating mechanism, and the regulation precision of the position distance is +/-10 um.
5. The dual spray trace sample detection ionization source according to claim 1, wherein the sample to be detected is fixed on a three-dimensional adjustment support frame of the nano-liter electrospray ion source, the support frame is fixed on a linear slide rail, a first positioning part and a second positioning part are arranged on the slide rail, the first positioning part is used for determining the optimal position of sample introduction of the sample to be detected, and the second positioning part is used for calibrating the optimal position of a needle for replacing electrospray injection.
6. The dual spray trace sample detection ionization source according to claim 1, wherein the electrospray of the derivatization reagent and the electrospray of the sample to be detected are driven by an external high voltage, wherein the electrospray of the derivatization reagent is a direct current high voltage, and the electrospray of the sample to be detected is an alternating current square wave high voltage. The two sets of high-voltage systems are respectively isolated in power supply potential, the applied direct-current high voltage and voltage output are adjustable, the range of the voltage output is 0.5-3kV, the range of the alternating-current high voltage adjustment is 0.5-4kV, and the frequency is 10-1000Hz.
7. The dual spray trace sample detection ionization source according to claim 1, wherein the image acquisition device is installed at the output end of the derivatization reagent electrospray ion source and the nano-liter electrospray ion source, and the preferred value of the ion flow signal after the position adjustment of the derivatization reagent electrospray ion source and the nano-liter electrospray ion source is confirmed based on the two-path spray plume conditions acquired by the image acquisition device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211612523.2A CN116297803A (en) | 2022-12-14 | 2022-12-14 | Double-spray micro-sample detection ionization source |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211612523.2A CN116297803A (en) | 2022-12-14 | 2022-12-14 | Double-spray micro-sample detection ionization source |
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| Publication Number | Publication Date |
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| CN116297803A true CN116297803A (en) | 2023-06-23 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211612523.2A Pending CN116297803A (en) | 2022-12-14 | 2022-12-14 | Double-spray micro-sample detection ionization source |
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| CN (1) | CN116297803A (en) |
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- 2022-12-14 CN CN202211612523.2A patent/CN116297803A/en active Pending
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