A composite ionization source device for simultaneous mass spectrometry analysis of substances with different polarities

Abstract

The present invention discloses a composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities, comprising an electrospray extraction ionization source device and a dielectric barrier discharge device. The inlet of the dielectric barrier discharge device is connected to the outlet of the electrospray extraction ionization source device, which is used to connect to the inlet of a mass spectrometer. The solvent electrospray portion of the electrospray extraction ionization source device includes polar solvent electrospray and weakly polar solvent electrospray. In this solution, the two ionization source devices, the electrospray extraction ionization device and the dielectric barrier discharge device, are connected in series to achieve efficient ionization of polar substances and weakly polar and non-polar substances in sample spray droplets, respectively, thereby helping to improve the coverage of mass spectrometry analysis.

Description

Technical Field

[0001] The present invention relates to the technical field of mass spectrometry analysis, and in particular to a composite ionization source device for simultaneous mass spectrometry analysis of substances with different polarities. Background Art

[0002] A mass spectrometer is an instrument that separates and analyzes charged ions under the influence of an electromagnetic field. It primarily consists of an ionization source, a mass analyzer, and a detector. The ionization source, which ionizes the substance being analyzed into a charged state, is the first and most critical step in mass spectrometry analysis, and is therefore often referred to as the heart of the mass spectrometer.

[0003] A variety of ionization sources have been developed, but their ionization mechanisms lead to a bias in the substances they are suitable for. For example, commonly used electrospray ionization (ESI) and extractive electrospray ionization (EESI) are suitable for ionization analysis of polar molecules, while atmospheric pressure chemical ionization (APCI) and dielectric barrier discharge ionization (DBDI) are suitable for ionizing weakly polar and non-polar molecules. Most commercial instruments are equipped with multiple ion sources, such as ESI and APCI. Analyzing substances of different polarities often requires replacing the ion source, which is costly and cannot achieve simultaneous mass spectrometric analysis of polar, weakly polar, and non-polar substances in a single injection, thus presenting limitations.

[0004] To overcome the above limitations, composite ionization source devices have emerged. Existing composite ionization source technologies mostly combine atmospheric pressure photoionization with atmospheric pressure chemical ionization. However, existing composite ionization sources still have the following disadvantages:

[0005] 1. Both ionization techniques are suitable for the ionization of weakly polar and non-polar substances, but lack the ability to ionize and analyze polar substances. At the same time, polar substances are a very important part of mass spectrometry analysis and account for a high proportion.

[0006] 2. The sample must be atomized and heated into a gaseous state first, which requires a high level of sample purity. It is not suitable for the analysis of complex matrix samples and is not suitable for the ionization analysis of thermally unstable substances. Summary of the Invention

[0007] In view of this, the present invention provides a composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities. Through the series connection of two ionization source devices, an electrospray extraction ionization device and a dielectric barrier discharge device, efficient ionization of polar substances in sample spray droplets and weakly polar and non-polar substances is achieved respectively, thereby helping to improve the coverage of mass spectrometry analysis.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities, comprising an electrospray extraction ionization source device and a dielectric barrier discharge device;

[0010] The inlet of the dielectric barrier discharge device is connected to the outlet of the electrospray extraction ionization source device, and the outlet is used to be connected to the inlet of a mass spectrometer; wherein the solvent electrospray part of the electrospray extraction ionization source device includes polar solvent electrospray and weak polar solvent electrospray.

[0011] Preferably, the dielectric barrier discharge device comprises a dielectric tube, an electrode tube and a ring electrode;

[0012] The medium pipe is provided with an inlet for connecting to a gas delivery pipe to be ionized;

[0013] The first end of the electrode tube is inserted into the first end of the medium tube, and the second end is located outside the medium tube and connected to the outlet of the electrospray extraction ionization source device; the second end of the medium tube is used to be connected to the inlet of the mass spectrometer;

[0014] The ring electrode is sleeved on the outer wall of the dielectric tube and is electrically connected to the electrode tube via an AC high voltage power supply.

[0015] Preferably, the dielectric barrier discharge device further comprises:

[0016] The carbon fiber is located in the dielectric tube and is arranged on the outer wall of the first end of the electrode tube.

[0017] Preferably, it further comprises an insulating tube;

[0018] One end of the insulating tube is connected to the outlet of the electrospray extraction ionization source device, and the other end is connected to the second end of the electrode tube.

[0019] Preferably, it also includes a T-shaped transmission pipe and an air pump;

[0020] The first end of the T-shaped transmission tube is connected to the second end of the medium tube, the second end is used to be connected to the inlet of the mass spectrometer, and the third end is connected to the air inlet end of the vacuum pump.

[0021] Preferably, the electrospray extraction ionization source device comprises a sample spray device, a polar solvent electrospray device, a weak polar solvent electrospray device and an extraction ionization chamber;

[0022] The extraction ionization chamber is respectively provided with a sample spray droplet inlet, a polar solvent spray droplet inlet, a weak polar solvent spray droplet inlet and an outlet; an extension line of the sample spray droplet inlet to the inner cavity of the extraction ionization chamber intersects with an extension line of the polar solvent spray droplet inlet to the inner cavity of the extraction ionization chamber and an extension line of the weak polar solvent spray droplet inlet to the inner cavity of the extraction ionization chamber;

[0023] The sample spray droplet inlet of the extraction ionization chamber is connected to the outlet of the sample spray device, the polar solvent spray droplet inlet is connected to the outlet of the polar solvent electrospray device, the weak polar solvent spray droplet inlet is connected to the outlet of the weak polar solvent electrospray device, and the outlet is connected to the inlet of the dielectric barrier discharge device.

[0024] Preferably, the sample spray device comprises:

[0025] A high-frequency microporous oscillator is provided at the sample spray droplet inlet of the extraction ionization chamber and is used for injecting or dripping the sample.

[0026] Preferably, the electrospray extraction ionization source device further includes a DC high-voltage power supply and a high-frequency switching switch;

[0027] The polar solvent electrospray device includes a polar solvent spray body;

[0028] The weak polar solvent electrospray device comprises a weak polar solvent spray body;

[0029] The DC high-voltage power supply is communicatively connected to the high-frequency switching switch, and the high-frequency switching switch is electrically connected to the capillary of the polar solvent spray body and the capillary of the weak polar solvent spray body respectively.

[0030] Preferably, the polar solvent spray body includes a polar solvent injection pump and a polar electrospray capillary; the inlet end of the polar electrospray capillary is connected to the outlet end of the polar solvent injection pump, the outlet end is connected to the polar solvent spray droplet inlet, and is electrically connected to the high-frequency switch;

[0031] The weak polar solvent spray body includes a weak polar solvent injection pump and a weak polar electrospray capillary; the inlet end of the weak polar electrospray capillary is connected to the outlet end of the weak polar solvent injection pump, the outlet end is connected to the weak polar solvent spray droplet inlet, and is electrically connected to the high-frequency switching switch.

[0032] Preferably, the sample spray droplet inlet is opened at the top of the extraction ionization chamber, the polar solvent spray droplet inlet and the weak polar solvent spray droplet inlet are opened on the same side wall of the extraction ionization chamber, and the outlet is opened on the other side wall of the extraction ionization chamber and is respectively arranged opposite to the polar solvent spray droplet inlet and the weak polar solvent spray droplet inlet;

[0033] The outlet end of the polar electrospray capillary is tilted downward in the horizontal direction and connected to the polar solvent spray droplet inlet, and the outlet end of the weak polar electrospray capillary is tilted upward in the horizontal direction and connected to the weak polar solvent spray droplet inlet.

[0034] As can be seen from the above technical solution, the composite ionization source device provided by the present invention for simultaneous mass spectrometry analysis of substances of different polarities, through the series design of two ionization source devices, an electrospray extraction ionization device and a dielectric barrier discharge device, facilitates the efficient ionization of polar substances and weakly polar and non-polar substances in sample spray droplets, thereby helping to improve the coverage of mass spectrometry analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 A simplified structural diagram of a composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities provided by an embodiment of the present invention;

[0037] Figure 2 This is a flow chart of a composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities provided by an embodiment of the present invention.

[0038] Among them, 1 is a high-frequency microporous oscillator, 2 is an extraction ionization chamber, 3 is a sample solution capillary, 4 is a polar electrospray capillary, 5 is a weak polar electrospray capillary, 6 is an insulating tube, 7 is an electrode tube, 8 is a carbon fiber, 9 is a dielectric tube, 10 is a ring electrode, 11 is a gas delivery tube to be ionized, 12 is a T-type transmission tube, 13 is an exhaust pump, and 14 is a mass spectrometer. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] The embodiment of the present invention provides a composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities, such as Figure 1 As shown, it includes an electrospray extraction ionization source device and a dielectric barrier discharge device;

[0041] The inlet of the dielectric barrier discharge device is connected to the outlet of the electrospray extraction ionization source device, and the outlet is used to be connected to the inlet of the mass spectrometer 14; wherein the solvent electrospray part of the electrospray extraction ionization source device includes polar solvent electrospray and weak polar solvent electrospray.

[0042] It should be noted that the electrospray extraction ionization source also includes a sample spray section. More specifically, the sample spray droplets formed by the sample spray section undergo collision extraction and charge transfer reactions with the solvent spray droplets formed by two electrosprays of solvents of different polarities. The polar solvent electrospray extracts and ionizes polar analytes in the sample spray droplets, while the weakly polar solvent electrospray extracts weakly polar or non-polar analytes in the sample spray droplets. However, due to the limited charge of the weakly polar solvent electrospray, the weakly polar or non-polar analytes are not ionized at this time. To address this issue, the present solution utilizes a series design of two ionization source devices, an electrospray extraction ionization device and a dielectric barrier discharge device. This allows the droplets that have extracted the weakly polar or non-polar analytes to enter the dielectric barrier discharge device for further ionization. The plasma triggers a molecular ion reaction between water molecules in the air and the analytes, ionizing the weakly polar or non-polar analytes. This facilitates the simultaneous ionization of polar, weakly polar, and non-polar substances in the sample.

[0043] That is to say, the electrospray extraction and ionization device and the dielectric barrier discharge device of this scheme are designed in series. The electrospray extraction and ionization device can first be used to extract and ionize the polar analytes that account for a relatively high proportion in the sample electrospray droplets, and then the dielectric barrier discharge device can be used to further ionize the weakly polar and non-polar analytes that account for a relatively small proportion in the sample electrospray droplets and that have only been extracted but not ionized in the electrospray extraction and ionization stage, thereby helping to achieve the simultaneous ionization of polar, weakly polar and non-polar substances in a single injection.

[0044] As can be seen from the above technical solution, the composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities provided in the embodiment of the present invention, through the series design of two ionization source devices, an electrospray extraction ionization device and a dielectric barrier discharge device, facilitates the efficient ionization of polar substances and weakly polar and non-polar substances in the sample spray droplets, thereby helping to improve the coverage of mass spectrometry analysis.

[0045] Specifically, if Figure 1 As shown, the dielectric barrier discharge device includes a dielectric tube 9, an electrode tube 7 and a ring electrode 10;

[0046] The medium pipe 9 is provided with an inlet for connecting to a gas delivery pipe 11 to be ionized; wherein the gas to be ionized may be helium;

[0047] The first end of the electrode tube 7 is inserted into the first end of the medium tube 9, and the second end is located outside the medium tube 9 and connected to the outlet of the electrospray extraction ionization source device; the second end of the medium tube 9 is used to connect to the inlet of the mass spectrometer 14;

[0048] Ring electrode 10 is sleeved onto the outer wall of dielectric tube 9 and electrically connected to electrode tube 7 via an AC high-voltage power supply. The dielectric barrier discharge device of this embodiment is designed to achieve a flow-through dielectric barrier discharge effect, resulting in better ionization of weakly polar and non-polar substances in the sample electrospray droplets. Furthermore, the device features a simple structure and ease of design. Preferably, dielectric tube 9 can be a quartz tube, electrode tube 7 can be a stainless steel tube, and ring electrode 10 can be a copper ring electrode.

[0049] Furthermore, if Figure 1 As shown, the dielectric barrier discharge device further includes:

[0050] Carbon fibers 8 are located within the dielectric tube 9 and are disposed on the outer wall of the first end of the electrode tube 7. In other words, in this embodiment, the outer wall of the first end of the electrode tube 7 is modified with carbon fibers 8 to improve discharge efficiency and generate more plasma, thereby helping to improve the ionization efficiency of the dielectric barrier discharge device.

[0051] Furthermore, in order to achieve electrical isolation between the electrospray extraction and ionization device and the electrode tube 7 and ensure safe cooperation between the electrospray extraction and ionization device and the dielectric barrier discharge device; accordingly, as Figure 1 As shown, the composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities provided by the embodiment of the present invention further includes an insulating tube 6;

[0052] One end of the insulating tube 6 is connected to the outlet of the electrospray extraction ionization source device, and the other end is connected to the second end of the electrode tube 7.

[0053] In order to further optimize the above technical solution, Figure 1As shown, the composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities provided by the embodiment of the present invention further includes a T-shaped transmission tube 12 and an air pump 13;

[0054] The first end of the T-shaped transmission tube 12 is connected to the second end of the medium tube 9, the second end is connected to the inlet of the mass spectrometer 14, and the third end is connected to the air inlet of the vacuum pump 13. In this solution, the vacuum pump 13 removes excess gas from the ions, thereby preventing ion loss due to gas diffusion and improving ion transmission efficiency.

[0055] In this program, if Figure 1 As shown, the electrospray extraction ionization source device includes a sample spray device, a polar solvent electrospray device, a weak polar solvent electrospray device and an extraction ionization chamber 2;

[0056] The extraction ionization chamber 2 is respectively provided with a sample spray droplet inlet, a polar solvent spray droplet inlet, a weak polar solvent spray droplet inlet and an outlet; wherein, the extension line of the sample spray droplet inlet to the inner cavity of the extraction ionization chamber 2 intersects with the extension line of the polar solvent spray droplet inlet to the inner cavity of the extraction ionization chamber 2 and the extension line of the weak polar solvent spray droplet inlet to the inner cavity of the extraction ionization chamber 2 respectively;

[0057] The sample spray droplet inlet of the extraction ionization chamber 2 is connected to the outlet of the sample spray device, the polar solvent spray droplet inlet is connected to the outlet of the polar solvent electrospray device, the weak polar solvent spray droplet inlet is connected to the outlet of the weak polar solvent electrospray device, and the outlet is connected to the inlet of the dielectric barrier discharge device.

[0058] It should be noted that the inner extension line of the sample spray droplet inlet intersects with the inner extension line of the polar solvent spray droplet inlet and the inner extension line of the weak polar solvent spray droplet inlet, respectively, so that the sample spray droplets and the two solvent spray droplets of different polarities can form an intersection point in the extraction ionization chamber 2, thereby causing the three types of spray droplets to undergo collision extraction and charge transfer in the extraction ionization chamber 2, extracting and ionizing the corresponding analytes in the sample. Among them, the polar solvent electrospray extracts and ionizes the polar analytes in the sample spray droplets, and the weak polar solvent electrospray extracts and ionizes the weak polar and non-polar analytes in the sample spray droplets. In other words, the electrospray extraction ionization of this scheme occurs in the extraction ionization chamber 2, which can avoid being affected by external factors such as ambient airflow, and the angles of the two solvent spray droplets of different polarities and the spatial positions between them and the outlet of the electrospray extraction ionization source device are fixed, thereby helping to improve the stability and repeatability of the electrospray extraction ionization.

[0059] Specifically, if Figure 1 As shown, the sample spray device includes:

[0060] A high-frequency microporous oscillator 1 is provided at the sample spray droplet inlet of the extraction ionization chamber 2 and is used to inject or drip the sample. The sample is applied to the high-frequency microporous oscillator 1, and under the action of high-frequency oscillation, the sample quickly passes through the microporous plate of the high-frequency microporous oscillator 1 and is broken into micron-sized droplet sprays, and then enters the extraction ionization chamber 2. In addition, this solution uses the high-frequency microporous oscillator 1 as a sample spray device to facilitate atomizing the sample into a micron-sized droplet plume, which is not only suitable for continuously flowing solution samples, but also for droplet samples, cell samples, etc., and the microporous oscillation cutting atomization can break up cell samples and release intracellular substances into the sample droplets, so that the composite ionization source device can complete the broad-spectrum mass spectrometry analysis of polar, weakly polar, and non-polar substances in single cells.

[0061] In addition, if Figure 1 As shown, the sample spray device further includes a sample solution injection pump and a sample solution capillary 3;

[0062] The inlet end of the sample solution capillary tube 3 is connected to the outlet end of the sample solution injection pump, which is used to align with the high-frequency microporous oscillator 1. That is, the outlet end of the sample solution capillary tube 3 forms an aligned fit with the microporous plate of the high-frequency microporous oscillator 1. This design facilitates automatic injection of the sample solution into the high-frequency microporous oscillator 1. Furthermore, a non-nebulizing gas-assisted sample solution injection pump is used to power the sample solution transmission. This means that the sample spray device is non-nebulizing gas-assisted, thus eliminating the limitation of using cylinder gas, reducing operating costs, and making the device portable, integrated, and portable.

[0063] Furthermore, the electrospray extraction ionization source device also includes a DC high-voltage power supply and a high-frequency switching switch;

[0064] The polar solvent electrospray device comprises a polar solvent spray body;

[0065] The weak polar solvent electrospray device comprises a weak polar solvent spray body;

[0066] The DC high-voltage power supply is communicatively connected to the high-frequency switching switch, and the high-frequency switching switch is electrically connected to the capillary of the polar solvent spray body and the capillary of the weak polar solvent spray body, respectively. This solution is designed so that the high-voltage electricity provided by the DC high-voltage power supply can be switched and output to the capillaries of the polar solvent spray body and the weak polar solvent spray body through the high-frequency switching switch, thereby realizing the alternating occurrence of polar and weak polar solvent electrospray, thereby facilitating the extraction and ionization of polar and weak polar substances in the sample droplets. In other words, this solution uses a dual-solvent electrospray device with different polarities to facilitate the alternating electrospray of polar and weak polar solvents, thereby facilitating the extraction and ionization of polar and weak polar substances in the sample droplets, thereby maximizing the simultaneous ionization analysis of multiple substances. In addition, it is not difficult to see that the polar solvent electrospray device and the weak polar solvent electrospray device of this solution share the same DC high-voltage power supply.

[0067] Furthermore, if Figure 1 As shown, the polar solvent spray body includes a polar solvent injection pump and a polar electrospray capillary 4; the inlet end of the polar electrospray capillary 4 is connected to the outlet end of the polar solvent injection pump, the outlet end is connected to the polar solvent spray droplet inlet, and is electrically connected to the high-frequency switching switch;

[0068] The weakly polar solvent spraying body includes a weakly polar solvent injection pump and a weakly polar electrospray capillary 5; the inlet end of the weakly polar solvent injection pump is connected to the outlet end of the weakly polar solvent injection pump, and the outlet end is connected to the weakly polar solvent spray droplet inlet and is electrically connected to a high-frequency switching switch. This solution is designed so that both solvent spraying bodies with different polarities use solvent injection pumps without the assistance of atomizing gas to provide power for electrospray solvent transmission. This means that both solvent electrospraying devices are non-atomizing gas-assisted solvent electrospraying devices, thus eliminating the limitation of using cylinder gas, reducing usage costs, and making the device easy to integrate and move.

[0069] Specifically, if Figure 1 As shown, the sample spray droplet inlet is opened at the top of the extraction ionization chamber 2, so that the sample spray droplets can fall vertically and naturally into the extraction ionization chamber 2, wherein the bottom end of the high-frequency microporous oscillation plate 1 is connected to the top of the extraction ionization chamber 2; the polar solvent spray droplet inlet and the weak polar solvent spray droplet inlet are opened on the same side wall of the extraction ionization chamber 2, and the outlet is opened on the other side wall of the extraction ionization chamber 2, and is respectively arranged opposite to the polar solvent spray droplet inlet and the weak polar solvent spray droplet inlet;

[0070] like Figure 1As shown, the outlet end of the polar electrospray capillary 4 is tilted downward in the horizontal direction and connected to the polar solvent spray droplet inlet, and the outlet end of the weak polar electrospray capillary 5 is tilted upward in the horizontal direction and connected to the weak polar solvent spray droplet inlet. In other words, the polar and weak polar solvent electrosprays of this solution are successively introduced from the side wall of the extraction ionization chamber 2 at a certain angle in the horizontal direction, and interact with the vertically falling sample spray droplets in the extraction ionization chamber 2 to extract and ionize the polar and weak polar substances to be tested, respectively, and then enter the dielectric barrier discharge device for further ionization. This solution is designed so that the high-speed airflow direction of the two beams of solvent electrospray is consistent with the outlet direction of the extraction ionization chamber 2, avoiding affecting the transmission efficiency of ions.

[0071] The present invention will be further described below with reference to specific embodiments:

[0072] The present invention relates to constructing a composite ionization source device for simultaneous mass spectrometry analysis of polar, weakly polar and non-polar substances in complex matrix samples. The device is composed of two ionization modules in series: microporous oscillation-electrospray extraction ionization and flow-through dielectric barrier discharge. The sample (including continuous flow solution, droplets, cells, etc.) is cut into micron-sized spray droplets in a vertical downward direction through a high-frequency microporous vibration plate. The polar solvent electrospray in the horizontal direction (including a certain angle) extracts and ionizes the polar substances in the sample droplets, and the other weakly polar solvent electrospray only extracts the weakly polar and non-polar substances in the sample, which are transferred to the dielectric barrier discharge module for ionization. At this point, the extraction and ionization of the polar, weakly polar and non-polar substances in the sample are completed, and the sample enters the mass spectrometer for analysis.

[0073] The present invention relates to a composite ionization source for simultaneous mass spectrometry analysis of polar, weakly polar, and non-polar substances, which is composed of two ionization modules connected in series: microporous oscillation-electrospray extraction ionization and flow-through dielectric barrier discharge. The overall action flow chart of the present invention is as follows: Figure 2 As shown in the figure. A continuous-flow solution, droplets, or cell sample comes into contact with a high-frequency microporous oscillator, sheared and atomized into micron-sized droplets, which then enter the extraction and ionization chamber vertically. Two electrosprays of solvents of different polarity are introduced horizontally (at a certain inclination angle) from the sidewalls of the extraction and ionization chamber. The micron-sized electrospray droplets collide with the sample droplets, extracting and reacting with the sample droplets. The polar solvent electrospray extracts and ionizes polar analytes in the sample droplets, while the weakly polar solvent electrospray extracts weakly polar or non-polar substances in the sample droplets. Due to the limited charge of the non-polar electrospray, the weakly polar or non-polar substances are not ionized at this time. The small droplets containing the weakly polar or non-polar substances enter the dielectric barrier discharge module, where the plasma triggers a molecular ion reaction between water molecules in the air and the analyte, ionizing the weakly polar or non-polar substances. This achieves the simultaneous ionization of polar, weakly polar, and non-polar substances in the sample, which then enter the mass spectrometer for analysis.

[0074] Working principle of this device:

[0075] Driven by a 24V DC voltage, the microporous vibrator vibrates up and down at high frequency. The center vibrator is covered with micron-sized pores. Continuously flowing solutions, droplets, cells, and other samples come into contact with the vibrator, where they are instantly atomized into micron-sized droplets (cells are disrupted). These droplets then vertically descend into the cylindrical extraction ionization chamber. Two electrosprays of solvents of different polarities are introduced into the sidewalls of the extraction ionization chamber. Based on the principle of like dissolves like, the polar electrospray droplets extract polar substances in the sample. Polar electrosprays have a high charge and can ionize polar substances through charge transfer reactions. Weakly polar electrospray droplets extract weakly polar and non-polar substances, but their charge is low and cannot completely ionize these substances. These droplets enter the dielectric barrier discharge module, where, under the action of plasma, they react with water molecules in the air to form molecular ions, completing ionization. The composite ionization source now completely extracts and ionizes polar, weakly polar, and non-polar substances before entering the mass spectrometer.

[0076] The structure, components and functions of this device:

[0077] The schematic diagram of the device structure of the present invention is as follows Figure 1 As shown, where:

[0078] The high-frequency microporous oscillator 1, with a selectable diameter (10-30mm) and number of micropores (1000-3000 mesh), is driven by a 24V DC voltage. During operation, the sample solution penetrates the microporous plate under the action of high-frequency oscillation, being cut into a spray of micron-sized droplets. During cell sample analysis, the cell membrane is also disrupted, releasing intracellular substances. A continuous flow of sample solution is introduced through the sample solution capillary 3, and the atomized droplets enter the extraction and ionization chamber 2.

[0079] The extraction ionization chamber 2 is manufactured by 3D printing. It has openings at the top and bottom, with the top connected to the microporous oscillator. It also has openings on the side walls, which are connected to the polar electrospray capillary 4, the weakly polar electrospray capillary 5, and the polyetheretherketone insulating tube, respectively. This is where the spray converges and the extraction ionization occurs.

[0080] Sample solution capillary 3.

[0081] The polar electrospray capillary 4 has an outer diameter of 360 μm, an inner diameter of 20 μm, and a tip inner diameter of 10 μm. It generates polar electrospray under the action of a DC high voltage (3-5 kV). The spray plume interacts and collides with the sample droplets in the extraction and ionization chamber 2 to extract and ionize the polar analytes in the sample droplets.

[0082] The weakly polar electrospray capillary 5 has an outer diameter of 360 μm, an inner diameter of 20 μm, and a tip inner diameter of 10 μm. It generates weakly polar electrospray under the action of a high DC voltage (4-6 kV). The spray plume interacts and collides with the sample droplets in the extraction and ionization chamber 2, extracting (not ionizing) the polar analytes in the sample droplets.

[0083] The polyetheretherketone insulating tube (ie, insulating tube 6 ) connects the extraction ionization chamber 2 and the carbon fiber-modified stainless steel electrode tube (ie, electrode tube 7 ) in the dielectric barrier discharge module for connection and ion transmission.

[0084] The carbon fiber-modified stainless steel electrode tube, one of the electrodes in the dielectric barrier discharge module, is connected to the copper ring electrode (ie, the ring electrode 10) through AC high voltage (2-4 kV, 5-50 kHz).

[0085] The carbon fiber 8 modified on the surface of the stainless steel electrode improves the discharge efficiency and generates more plasma, thereby improving the ionization efficiency.

[0086] The quartz tube (ie, the dielectric tube 9 ) is the dielectric of the charging dielectric barrier discharge module.

[0087] The copper ring electrode, one of the electrodes in the dielectric barrier discharge module, is connected to the carbon fiber-modified stainless steel electrode tube through AC high voltage (2-4kV, 5-50kHz).

[0088] The helium transmission tube (i.e., the gas transmission tube 11 to be ionized) provides helium to the dielectric barrier discharge module. When the helium is discharged by the electrode, it is ionized into plasma, triggering the reaction between water molecules in the air and the molecular ions of the substance to be tested, completing the ionization process.

[0089] The three ports of the T-shaped polyetheretherketone transmission tube (ie, the T-shaped transmission tube 12 ) are respectively connected to the dielectric barrier discharge cavity, the mass spectrometer inlet, and the vacuum pump for ion transmission and gas exhaust.

[0090] The air pump 13 is connected to one end of the T-shaped polyetheretherketone transmission tube to remove excess gas.

[0091] Workflow:

[0092] 1. Turn on the high-frequency microporous oscillating plate 1;

[0093] 2. Turn on the polar electrospray and weak polar electrospray. The two electrosprays are triggered alternately and controlled by a DC high-voltage power supply and a high-frequency switching switch.

[0094] 3. Turn on the AC high voltage of the dielectric barrier discharge module;

[0095] 4. Turn on the air pump 13;

[0096] 5. Introduce helium from the helium transfer tube at a flow rate of 1-3 L / min;

[0097] 6. Introduce the sample from the sample solution capillary 3, or directly add droplets or cell samples to the high-frequency microporous oscillator 1.

[0098] 7. Collect mass spectrometry data.

[0099] Processing: The extraction ionization chamber 2 is manufactured using 3D printing. The carbon fiber-modified stainless steel electrode tube is electrochemically modified with carbon fibers. Other components, such as the high-frequency microporous oscillator, DC high-voltage power supply, transfer capillary, and electrospray capillary, are commercially available.

[0100] Advantages of the present invention:

[0101] 1. The two ionization modules, microporous oscillation-electrospray extraction ionization and flow-through dielectric barrier discharge, are connected in series to achieve efficient ionization of polar substances and weakly polar and non-polar substances, respectively, thereby improving the coverage of mass spectrometry analysis.

[0102] 2. The microporous oscillation-electrospray extraction and ionization method can effectively reduce the influence of matrix interference in the sample on ionization and improve the ionization efficiency;

[0103] 3. Microporous oscillation cutting atomization can break up cell samples and release intracellular substances into sample droplets. The composite ionization source can complete the broad-spectrum mass spectrometry analysis of polar, weakly polar, and non-polar substances in single cells.

[0104] The key points and points to be protected of the present invention are:

[0105] 1. Microporous oscillation-electrospray extraction ionization and flow-through dielectric barrier discharge constitute a composite ionization source, which can achieve simultaneous ionization of polar, weakly polar and non-polar substances in a single injection;

[0106] 2. Using carbon fiber modified stainless steel tubes as the inner electrodes of the flow-through dielectric barrier discharge improves the discharge and plasma generation efficiency, thereby improving the ionization efficiency;

[0107] 3. Use a vacuum pump to discharge excess gas, avoiding ion loss caused by gas diffusion and improving ion transmission efficiency.

[0108] Explanation of terms related to this plan:

[0109] A mass spectrometer is an instrument that uses an electromagnetic field to separate and detect charged ions based on their mass / charge ratio. A mass spectrometer primarily consists of an ionization source, a mass analyzer, and a detector.

[0110] Ionization source: A device that ionizes a sample solution (neutral, uncharged) into charged ions.

[0111] Microporous oscillating sheet: A metal sheet with a micron-sized aperture is embedded in an oscillator. Through high-frequency oscillation, the liquid in contact with the metal sheet can be directly cut and atomized into micron-sized droplets.

[0112] Electrospray: The solvent flows through the capillary, and a high DC voltage is applied at the outlet of the capillary. Under the action of the electric field force and Coulomb force, the solvent molecules will spray at the outlet of the capillary and atomize into small droplets with electric charge in the micron size.

[0113] Polar electrospray: Electrospray produced by polar solvents.

[0114] Weakly polar electrospray: Electrospray produced by weakly polar solvents.

[0115] Electrospray extraction and ionization: The sample electrospray and the pure solvent electrospray cross-collide at a certain angle, causing droplet collision extraction and charge transfer, thereby extracting and ionizing the analyte in the sample.

[0116] Dielectric barrier discharge: A non-equilibrium gas discharge in which an insulating dielectric is inserted into the discharge space, which can produce stable low-temperature plasma at atmospheric pressure.

[0117] Continuous flow solution: A solution that flows continuously at a certain speed (1-10 μl / min).

[0118] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0119] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities, characterized in that: It includes an electrospray extraction ionization source device and a dielectric barrier discharge device; The inlet of the dielectric barrier discharge device is connected to the outlet of the electrospray extraction ionization source device, and the outlet is used to be connected to the inlet of a mass spectrometer (14); wherein the solvent electrospray part of the electrospray extraction ionization source device includes polar solvent electrospray and weak polar solvent electrospray; The dielectric barrier discharge device comprises a dielectric tube (9), an electrode tube (7) and a ring electrode (10); The medium pipe (9) is provided with an inlet for connecting to a gas delivery pipe (11) to be ionized; The first end of the electrode tube (7) is inserted into the first end of the medium tube (9), and the second end is located outside the medium tube (9) and connected to the outlet of the electrospray extraction ionization source device; the second end of the medium tube (9) is used to be connected to the inlet of the mass spectrometer (14); The ring electrode (10) is sleeved on the outer wall of the dielectric tube (9) and is electrically connected to the electrode tube (7) via an AC high-voltage power supply; The dielectric barrier discharge device further comprises: A carbon fiber (8) is located in the medium tube (9) and is arranged on the outer wall of the first end of the electrode tube (7).

2. The composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities according to claim 1, characterized in that: Also includes an insulating tube (6); One end of the insulating tube (6) is connected to the outlet of the electrospray extraction ionization source device, and the other end is connected to the second end of the electrode tube (7).

3. The composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities according to claim 1, characterized in that: It also includes a T-shaped transmission pipe (12) and an air pump (13); The first end of the T-shaped transmission tube (12) is connected to the second end of the medium tube (9), the second end is used to be connected to the inlet of the mass spectrometer (14), and the third end is connected to the air inlet end of the vacuum pump (13).

4. The composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities according to claim 1, characterized in that: The electrospray extraction ionization source device comprises a sample spray device, a polar solvent electrospray device, a weak polar solvent electrospray device and an extraction ionization chamber (2); The extraction ionization chamber (2) is respectively provided with a sample spray droplet inlet, a polar solvent spray droplet inlet, a weak polar solvent spray droplet inlet and an outlet; an extension line of the sample spray droplet inlet to the inner cavity of the extraction ionization chamber (2) intersects with an extension line of the polar solvent spray droplet inlet to the inner cavity of the extraction ionization chamber (2) and an extension line of the weak polar solvent spray droplet inlet to the inner cavity of the extraction ionization chamber (2); The sample spray droplet inlet of the extraction ionization chamber (2) is connected to the outlet of the sample spray device, the polar solvent spray droplet inlet is connected to the outlet of the polar solvent electrospray device, the weak polar solvent spray droplet inlet is connected to the outlet of the weak polar solvent electrospray device, and the outlet is connected to the inlet of the dielectric barrier discharge device.

5. The composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities according to claim 4, characterized in that: The sample spray device comprises: A high-frequency microporous oscillating plate (1) is provided at the sample spray droplet inlet of the extraction ionization chamber (2) and is used for injecting or dripping the sample.

6. The composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities according to claim 4, characterized in that: The electrospray extraction ionization source device also includes a DC high-voltage power supply and a high-frequency switching switch; The polar solvent electrospray device includes a polar solvent spray body; The weak polar solvent electrospray device comprises a weak polar solvent spray body; The DC high-voltage power supply is communicatively connected to the high-frequency switching switch, and the high-frequency switching switch is electrically connected to the capillary of the polar solvent spray body and the capillary of the weak polar solvent spray body respectively.

7. The composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities according to claim 6, characterized in that: The polar solvent spray body comprises a polar solvent injection pump and a polar electrospray capillary (4); the inlet end of the polar electrospray capillary (4) is connected to the outlet end of the polar solvent injection pump, the outlet end is connected to the polar solvent spray droplet inlet, and is electrically connected to the high-frequency switch; The weak polar solvent spray body comprises a weak polar solvent injection pump and a weak polar electrospray capillary (5); the inlet end of the weak polar electrospray capillary (5) is connected to the outlet end of the weak polar solvent injection pump, the outlet end is connected to the weak polar solvent spray droplet inlet, and is electrically connected to the high-frequency switching switch.

8. The composite ionization source device for simultaneous mass spectrometry analysis of substances of different polarities according to claim 7, characterized in that: The sample spray droplet inlet is opened at the top of the extraction ionization chamber (2), the polar solvent spray droplet inlet and the weak polar solvent spray droplet inlet are opened on the same side wall of the extraction ionization chamber (2), and the outlet is opened on the other side wall of the extraction ionization chamber (2), and is respectively arranged opposite to the polar solvent spray droplet inlet and the weak polar solvent spray droplet inlet; The outlet end of the polar electrospray capillary (4) is tilted downward in the horizontal direction and connected to the polar solvent spray droplet inlet, and the outlet end of the weak polar electrospray capillary (5) is tilted upward in the horizontal direction and connected to the weak polar solvent spray droplet inlet.

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