Ionization source control apparatus and method, mass spectrometer detection system and method

Abstract

At least one embodiment of this disclosure provides an ionization source control device, an ionization source control method, a mass spectrometer detection system, and a mass spectrometer detection method. The ionization source control device includes: an electrode structure, the electrode structure including a cavity, wherein the cavity includes an ion generation region and a reaction region; an ion generator configured to generate ions in the ion generation region; a voltage controller configured to apply a positive voltage or a negative voltage to the electrode structure, and switch between the positive and negative voltages to control the ions; and a sample inlet tube configured to allow the analyte flowing into the sample inlet tube to undergo a chemical ionization reaction with the controlled ions in the reaction region. This ionization source control device can rely solely on the voltage controller to apply a positive voltage or a negative voltage to the electrode structure, and switch between the positive and negative voltages to control the ions, thereby separating different ions.

Description

Technical Field

[0001] Embodiments of this disclosure relate to an ionization source control device, an ionization source control method, a mass spectrometer detection system, and a mass spectrometer detection method. Background Technology

[0002] Chemical ionization mass spectrometry (CIE) based on selected ion reactions mainly includes selected ion flow tube mass spectrometry (SELECTI), selected ion proton transfer reaction (SELECTI), and ion-molecular reaction mass spectrometry (IMR). CIE can be used for the rapid detection and monitoring of trace organic compounds in many fields, including air pollution, water pollution, medical diagnostics, and food safety. Therefore, research on CIE has received considerable attention in recent years. CIE offers advantages such as soft ionization, high sensitivity, fast analysis speed, reliable qualitative and quantitative analysis, and adjustable detection range, making it a promising technology for detecting trace organic compounds in gases, liquids, and solids.

[0003] A mass spectrometer is a scientific instrument used to analyze and detect the composition of ions in the gas phase. It can quickly provide the mass-to-charge ratio of various ions in the gas phase, thereby determining their molecular structure. The type of mass analyzer determines the detection sensitivity and mass resolution of a mass spectrometer. An orbital trap is an advanced mass analyzer that can enrich, store, and simultaneously detect ions in the gas phase. It obtains the mass-to-charge ratio information of various ions by measuring the oscillation frequency of the trapped ions, enabling ultra-high resolution measurement of positive or negative ions. Summary of the Invention

[0004] At least one embodiment of this disclosure provides an ionization source control device, an ionization source control method, a mass spectrometer detection system, and a mass spectrometer detection method. The ionization source control device can rely solely on a voltage controller to apply a positive voltage or a negative voltage to the electrode structure, switching between positive and negative voltages to control ions, thereby separating different ions and allowing them to enter the reaction zone separately, so that the controlled ions and the analyte undergo a chemical ionization reaction in the reaction zone.

[0005] At least one embodiment of this disclosure provides an ionization source control device, comprising: an electrode structure including a cavity, wherein the cavity includes an ion generation region and a reaction region; an ion generator configured to generate ions in the ion generation region; a voltage controller configured to apply a positive voltage or a negative voltage to the electrode structure, and to switch the positive voltage and the negative voltage to control the ions; and a sample inlet tube configured to allow the analyte flowing into the sample inlet tube to undergo a chemical ionization reaction with the controlled ions in the reaction region.

[0006] For example, in an ionization source control device provided in at least one embodiment of this disclosure, the electrode structure includes a first electrode group, the first electrode group including a first electrode structure and a second electrode structure arranged sequentially and insulated in a first direction, and the cavity extends in the first direction.

[0007] For example, in an ionization source control device provided in at least one embodiment of this disclosure, the cavity further includes a transition region between the ion generation region and the reaction region; the sample inlet tube extends from outside the cavity in the first direction to the junction of the transition region and the reaction region.

[0008] For example, in at least one embodiment of the ionization source control device provided in this disclosure, the voltage controller includes a first DC power supply, a time relay, and a switch connected in sequence, and a second DC power supply connected to the time relay; the first DC power supply is configured to simultaneously provide a positive voltage or simultaneously provide a negative voltage to the first electrode structure and the second electrode structure; the second DC power supply is configured to provide a pulse voltage signal to the time relay to control the time relay to open and close; the time relay is configured to control the switching of the connection contacts of the first and second terminals of the switch by opening and closing, so as to realize the switching of simultaneously applying a positive voltage and simultaneously applying a negative voltage to the first electrode structure and the second electrode structure.

[0009] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the sample inlet tube is conductive, the time relay is configured to control the first terminal of the switch to be connected to the first electrode structure and the second electrode structure, and the second terminal to be connected to the sample inlet tube; or, the time relay is configured to control the first terminal of the switch to be connected to the sample inlet tube, and the second terminal to be connected to the first electrode structure and the second electrode structure.

[0010] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the difference between the positive voltages simultaneously applied to the first electrode structure and the second electrode structure is greater than or equal to a first threshold; and the difference between the negative voltages simultaneously applied to the first electrode structure and the second electrode structure is greater than or equal to a second threshold.

[0011] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the positive voltage applied to the first electrode structure is +125V and the positive voltage applied to the second electrode structure is +110V; or the negative voltage applied to the first electrode structure is -125V and the negative voltage applied to the second electrode structure is -110V.

[0012] For example, in an ionization source control device provided in at least one embodiment of this disclosure, the first electrode structure includes a first hollow structure and a second hollow structure sleeved in the first hollow structure, and a portion of the sample inlet tube is in the second hollow structure.

[0013] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the end of the sample inlet tube located within the cavity is closer to the reaction zone than the end of the second empty cylinder structure that is closer to the reaction zone.

[0014] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the distance between the end of the sample inlet tube located in the cavity and the end of the second empty cylinder structure near the reaction zone is 2 mm to 8 mm.

[0015] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the second electrode structure includes a third hollow cylinder structure, the inner diameter of which is equal to the inner diameter of the first hollow cylinder structure.

[0016] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the electrode structure further includes a second electrode group, the first electrode group and the second electrode group are sequentially arranged and insulated in the first direction, and the second electrode group includes a third electrode structure and a fourth electrode structure that are sequentially arranged and insulated in the first direction.

[0017] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the first electrode structure includes a first hollow structure and a second hollow structure sleeved in the first hollow structure, the second electrode structure includes a third hollow structure, the third electrode structure includes a fourth hollow structure, the fourth electrode structure includes a fifth hollow structure, and the inner diameters of the first hollow structure, the third hollow structure, the fourth hollow structure and the fifth hollow structure are equal.

[0018] For example, in the ionization source control device provided in at least one embodiment of this disclosure, a portion of the injection tube is in the second empty cylinder structure, the end of the injection tube located in the cavity is closer to the reaction zone than the end of the second empty cylinder structure that is closer to the reaction zone, and the end of the injection tube located in the cavity is in the third empty cylinder structure.

[0019] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the first DC power supply is configured to simultaneously provide a positive voltage or simultaneously provide a negative voltage to at least two of the first electrode structure, the second electrode structure, the third electrode structure, and the fourth electrode structure; the second DC power supply is configured to provide a pulse voltage signal to the time relay to control the time relay to open and close; the time relay is configured to control the switching of the connection contacts of the first and second terminals of the switch by opening and closing it, so as to realize the switching of simultaneously applying a positive voltage and simultaneously applying a negative voltage to at least two of the first electrode structure, the second electrode structure, the third electrode structure, and the fourth electrode structure.

[0020] For example, in the ionization source control device provided in at least one embodiment of this disclosure, a gradually decreasing positive voltage or a gradually decreasing negative voltage is simultaneously applied to the first electrode structure, the second electrode structure, the third electrode structure, and the fourth electrode structure, and the difference between the positive voltages simultaneously applied to any two adjacent electrode structures is greater than or equal to a third threshold; the difference between the negative voltages simultaneously applied to any two adjacent electrode structures is greater than or equal to a fourth threshold.

[0021] For example, in the ionization source control device provided in at least one embodiment of this disclosure, the material of the electrode structure includes at least one of conductive metal, carbon-based conductive material, metal oxide and ceramic.

[0022] For example, at least one embodiment of the ionization source control device provided in this disclosure further includes a reaction gas supply component, wherein the reaction gas supply component includes a protective gas supply unit, a first gas supply unit, a second gas supply unit, and a zero air supply unit connected in sequence. The protective gas supply unit is configured to provide a protective gas, the first gas supply unit is configured to provide a gas for forming the negative ions, the second gas supply unit is configured to provide a gas for forming the positive ions, and the zero air supply unit is configured to provide purified air.

[0023] For example, at least one embodiment of the ionization source control device provided in this disclosure further includes a rectifier screen, wherein the rectifier screen is disposed between the reaction gas supply port corresponding to the reaction gas supply component and the ion generator.

[0024] At least one embodiment of this disclosure also provides a mass spectrometer detection system, which includes: the ionization source control device described in any of the above embodiments and a mass spectrometer connected to the ionization source control device.

[0025] For example, in a mass spectrometer detection system provided in at least one embodiment of this disclosure, the mass spectrometer includes a mass spectrometer sampling cone and an orbital trap mass spectrometer detector, wherein the axis of the mass spectrometer sampling cone in the first direction coincides with the axis of the sample inlet tube in the first direction.

[0026] For example, in the mass spectrometer detection system provided in at least one embodiment of this disclosure, the mass spectrometer sampling cone draws in the synthetic ions generated in the reaction zone through negative pressure aspiration and transmits them to the orbital trap mass spectrometer detector, and the orbital trap mass spectrometer detector switches between positive mode detection and negative mode detection synchronously according to the time of the positive and negative synthetic ions generated in the reaction zone.

[0027] For example, in the mass spectrometer detection system provided in at least one embodiment of this disclosure, the flow rate of the negative pressure aspiration gas of the mass spectrometer sampling cone is 1.2 L / min ~ 2.2 L / min.

[0028] For example, in the mass spectrometer detection system provided in at least one embodiment of this disclosure, the switching frequency of the positive mode detection and the negative mode detection set by the orbital trap mass spectrometer detector is consistent with the switching frequency of the positive voltage and the negative voltage set by the voltage controller.

[0029] For example, in the mass spectrometer detection system provided in at least one embodiment of this disclosure, the switching frequency between the positive mode detection and the negative mode detection of the orbital trap mass spectrometer detector is 1.2 Hz to 2.1 Hz, and the switching time between the positive voltage and the negative voltage set by the time relay is less than or equal to 0.1 s.

[0030] At least one embodiment of this disclosure also provides an ionization source control method, the ionization source control method comprising: forming ions in an ion generation region, wherein the ion generation region is an ion generation region in a cavity included in an electrode structure; applying a positive voltage or applying a negative voltage on the electrode structure, switching the positive voltage and the negative voltage to control the ions; and subjecting an analyte flowing in through a sample injection tube to a chemical ionization reaction with the controlled ions in a reaction region, wherein the reaction region is a reaction region in the cavity included in the electrode structure.

[0031] For example, in at least one embodiment of the ionization source control method provided in this disclosure, forming ions in the ion generation region includes: simultaneously forming positive ions and negative ions, wherein simultaneously forming positive ions and negative ions includes: providing positive ion reaction gas and negative ion reaction gas, introducing a mixture of the positive ion reaction gas and the negative ion reaction gas into the ion generation region, and forming the positive ions and the negative ions in the ion generation region under the action of the ion generator included in the ionization source control device on the mixture of the positive ion reaction gas and the negative ion reaction gas.

[0032] For example, in the ionization source control method provided in at least one embodiment of this disclosure, the positive ion reaction gas is nitric acid vapor, the negative ion reaction gas is diethylamine vapor, the positive ion is diethylamine cation, and the negative ion is nitrate ion.

[0033] For example, in the ionization source control method provided in at least one embodiment of this disclosure, the provision of positive ion reaction gas and negative ion reaction gas includes: sequentially providing nitrogen gas, concentrated nitric acid liquid, diethylamine liquid and zero air, forming nitric acid vapor and diethylamine vapor through liquid evaporation; the nitrogen gas carrying the nitric acid vapor and the diethylamine vapor is mixed and diluted with the zero air and then enters the ion generation region.

[0034] For example, in the ionization source control method provided in at least one embodiment of this disclosure, the electrode structure includes a first electrode group, the first electrode group including a first electrode structure and a second electrode structure arranged sequentially and insulated in a first direction, and the cavity extends in the first direction; applying a positive voltage or a negative voltage to the electrode structure, and switching the positive voltage and the negative voltage to control the ions includes: applying a first positive voltage and a second positive voltage to the first electrode structure and the second electrode structure respectively in a first time period to select the positive ions; applying a first negative voltage and a second negative voltage to the first electrode structure and the second electrode structure respectively in a second time period to select the negative ions, so as to achieve switching between the positive ions and the negative ions in adjacent first time periods and second time periods.

[0035] For example, in at least one embodiment of the ionization source control method provided in this disclosure, the ionization source control device includes a voltage controller, which includes a first DC power supply, a time relay, and a switch connected in sequence, and a second DC power supply connected to the time relay. The switching of the positive ions and the negative ions includes: the first DC power supply simultaneously providing a positive voltage or simultaneously providing a negative voltage to the first electrode structure and the second electrode structure; the second DC power supply providing a pulse voltage signal to the time relay to control the time relay to open and close; and the time relay controlling the switching of the connection contacts of the first and second terminals of the switch through its opening and closing, so as to switch between simultaneously applying a positive voltage and simultaneously applying a negative voltage to the first electrode structure and the second electrode structure.

[0036] For example, in the ionization source control method provided in at least one embodiment of this disclosure, the sample injection tube is conductive, the time relay controls the first end of the switch to be connected to the first electrode structure and the second electrode structure, and the second end is connected to the sample injection tube; or, the time relay controls the first end of the switch to be connected to the sample injection tube, and the second end is connected to the first electrode structure and the second electrode structure.

[0037] At least one embodiment of this disclosure also provides a mass spectrometer detection method, which includes: providing an ionization source control device as described in any of the above embodiments and a mass spectrometer connected to the ionization source control device. The mass spectrometer includes a mass sampling cone and an orbital trap mass spectrometer detector. The mass sampling cone draws in ions generated in the reaction zone through negative pressure aspiration and transmits them to the orbital trap mass spectrometer detector. The orbital trap mass spectrometer detector switches between positive mode detection and negative mode detection synchronously according to the time of positive and negative reaction ions generated in the reaction zone. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings of the embodiments will be briefly described below. Obviously, the drawings described below only relate to some embodiments of this disclosure and are not intended to limit this disclosure.

[0039] Figure 1 This is a schematic cross-sectional view of an ionization source control device provided in at least one embodiment of the present disclosure;

[0040] Figure 2 A cross-sectional structural schematic diagram of another ionization source control device provided in at least one embodiment of the present disclosure;

[0041] Figure 3 for Figure 2 Block diagram of the medium voltage controller;

[0042] Figure 4 for Figure 2 A schematic diagram illustrating the implementation of the voltage controller switching between positive and negative voltages;

[0043] Figure 5 A cross-sectional structural schematic diagram of another ionization source control device provided in at least one embodiment of the present disclosure;

[0044] Figure 6 A cross-sectional structural schematic diagram of another ionization source control device provided in at least one embodiment of the present disclosure;

[0045] Figure 7 A cross-sectional structural schematic diagram of a mass spectrometer detection system provided in at least one embodiment of this disclosure; and

[0046] Figure 8 This is a flowchart of an ionization source control method provided for at least one embodiment of the present disclosure. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0048] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as “comprising” or “including” mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as “connected” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as “upper,” “lower,” “left,” and “right” are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0049] Unless otherwise defined, the features such as "parallel," "perpendicular," and "identical" used in the embodiments of this invention include the strictly defined cases of "parallel," "perpendicular," and "identical," as well as cases involving a certain degree of error, such as "approximately parallel," "approximately perpendicular," and "approximately identical." For example, the aforementioned "approximately" may indicate that the difference between the compared objects is within 10% or 5% of the average value of the compared objects. Unless otherwise specified in the following embodiments of this invention, the quantity of a component or element is implied to mean that the component or element may be one or more, or can be understood as at least one. "At least one" refers to one or more, and "more" refers to at least two. In the embodiments of this invention, "same-layer arrangement" refers to the relationship between multiple film layers formed from the same material after undergoing the same step (e.g., a patterning process). Here, "same-layer" does not always mean that the multiple film layers have the same thickness or that the multiple film layers have the same height in a cross-sectional view.

[0050] Chemical ionization mass spectrometry (CIE) is an online gas phase analysis technique that plays a crucial role in air quality monitoring and atmospheric chemistry research. The principle of chemical ionization is that reactant ions undergo a molecular-ion reaction with a neutral analyte, resulting in ionization. The polarity, reaction pressure, and electronic structure of the reactant ions collectively determine the scope of chemical ionization, exhibiting specific selectivity and sensitivity to specific compound groups. Proton transfer reaction mass spectrometry (PTS) is currently the mainstream technique for analyzing volatile organic compounds (VOCs), utilizing hydrated hydrogen ions (H₃O₂). + As a reactive ion, proton transfer reaction mass spectrometry (PTMS) reacts with analytes under low pressure (~2 mbar) conditions, exhibiting excellent detection performance for molecules with low polarity and high volatility. However, PTTMS has poor selectivity for functionalized and low-volatility substances, failing to meet the detection requirements of the vast majority of oxygen-containing organic molecules in ambient air. Moreover, for this type of low-pressure chemical ionization source, the gaseous analyte is significantly diluted by 10 to 10 times upon entering the ionization source. 5 This limits the detection sensitivity due to the high concentration of oxygen-containing organic molecules, which can be several times higher than that of nitrate ions (NO3). To achieve highly sensitive detection of low concentrations of oxygen-containing organic molecules in the atmosphere, a method based on nitrate ions (NO3) is proposed. - ), iodide ions (I - ) and bromide ions (Br - Atmospheric pressure chemical ionization technology for negatively reacting ions such as nitrate ions (NO3) has been developed. - Chemical ionization mass spectrometry (CIE mass spectrometry) is widely used in atmospheric measurements due to its high sensitivity and selectivity to gaseous sulfuric acid and high-oxygen-content organic molecules. However, nitrate ions (NO3) are also susceptible to ionization. - The sensitivity of negative reaction ion techniques, such as those using ammonium ions (NH4+), decreases as the oxidation state of the analyte decreases, resulting in the undetectability of a large number of oxygen-containing organic molecules in intermediate and low oxidation states. With the development of chemical ionization techniques, ammonium ions (NH4+) have become increasingly important. + ) and diethylamine ions (C4H 12 N + Other positive reaction ion-type atmospheric pressure chemical ionization techniques, represented by [example], have been developed. These positive reaction ions can undergo ion attachment reactions with oxygen-containing organic molecules in medium and low oxidation states, thereby making up for the shortcomings of the above-mentioned proton transfer reaction mass spectrometry and negative reaction ion system chemical ionization techniques.

[0051] Different reactant ions, especially positive and negative reactant ions, exhibit significant differences in selectivity and sensitivity. Mass spectrometers using a single reactant ion system cannot achieve comprehensive detection of all volatile organic compounds and oxygen-containing organic compounds in the atmosphere. Although deployment schemes employing multiple chemical ionization mass spectrometers for simultaneous observation can provide comprehensive molecular feature identification of atmospheric gaseous components, a single chemical ionization mass spectrometer is typically expensive and bulky, and very few laboratories have the resources to equip themselves with multiple spectrometers. Therefore, developing a chemical ionization source that is versatile, easy to deploy, and capable of rapidly switching between various reactant ions with different chemical selectivities is an important direction for the development of chemical ionization mass spectrometry technology. The MION2 chemical ionization source, optimized and launched by the Finnish company KARSA in 2024, is currently the only publicly disclosed atmospheric pressure chemical ionization technology capable of switching between positive and negative reactant ion measurements. This chemical ionization source consists of two reactant ion generating chambers and one reaction chamber, using soft X-rays to irradiate HNO3 and C4H in the two reactant ion generating chambers, respectively. 12 N will generate nitrate ions NO3. - and diethylamine ions C4H 12 N + It relies on radio frequency voltages of up to several kilovolts to drive the reaction ions, and through time-series control, it enables nitrate ions (NO3) to react. - and diethylamine ions C4H 12 N + Alternating entry into the reaction chamber to ionize the analyte, but its relatively complex structure and high cost mean that there are still certain barriers to the widespread application of this technology.

[0052] In contrast, Eisele developed a flow-through tube NO3 - Chemical ionization sources are among the most widely used atmospheric pressure chemical ionization sources. Their simple and unique gas laminar flow structure design has been used since their invention and plays a crucial role in measuring oxygen-containing organic molecules in the atmosphere. Although studies have reported that Eisele-type chemical ionization sources can produce different reactive ion systems (e.g., NO3-),... - NH4 + and C4H 12 N + (etc.), but during operation, only one reaction ion mode can be selected for measurement. The reaction gas supply system and experimental setup need to be changed before another reaction ion mode can be measured. Currently, there is no research on using an Eisele-type chemical ionization source for real-time switching measurements of multiple reaction ions.

[0053] The inventors of this disclosure have noted that multiple reactive ions, such as positive and negative reactive ions, can be generated simultaneously in a single ionization source. Switching between positive and negative reactive ions is achieved solely through voltage regulation, thereby developing a novel, versatile, simple, and low-cost bipolar atmospheric pressure chemical ionization source for switching between positive and negative reactive ions. Furthermore, coupling this novel bipolar atmospheric pressure chemical ionization source with a mass spectrometer detector (such as an orbital trap mass spectrometer) capable of rapid switching between positive and negative modes provides a mass spectrometer detection system capable of more comprehensive molecular recognition of oxygen-containing organic molecules in the atmosphere.

[0054] At least one embodiment of this disclosure provides an ionization source control device, comprising: an electrode structure, an ion generator, a sample inlet tube, and a voltage controller. The electrode structure includes a cavity comprising an ion generation region and a reaction region. The ion generator is configured to generate ions in the ion generation region. The voltage controller is configured to apply a positive voltage or a negative voltage to the electrode structure, switching between the positive and negative voltages to control the ions. The sample inlet tube is configured to allow the analyte flowing into the sample inlet tube to undergo a chemical ionization reaction with the controlled ions in the reaction region. This ionization source control device can rely solely on the voltage controller to apply a positive or negative voltage to the electrode structure, switching between the positive and negative voltages to control the ions, thereby separating different ions and allowing them to enter the reaction region separately, so that the ions and the analyte undergo a chemical ionization reaction in the reaction region.

[0055] For example, Figure 1 This is a cross-sectional structural schematic diagram of an ionization source control device provided in at least one embodiment of the present disclosure, as shown below. Figure 1 As shown, the ionization source control device 100 includes: an electrode structure 101, an ion generator 102, a sample inlet tube 103, and a voltage controller 104. The electrode structure 101 includes a cavity 1011, which includes an ion generation region 1011a and a reaction region 1011b. The ion generator 102 is configured to generate ions in the ion generation region 1011a. The voltage controller 104 is configured to apply a positive voltage or a negative voltage to the electrode structure 101, switching between positive and negative voltages to control the ions. The sample inlet tube 103 is configured to allow the analyte flowing into the sample inlet tube 103 to undergo a chemical ionization reaction with the controlled ions in the reaction region 1011b. This ionization source control device can rely solely on the voltage controller to apply a positive or negative voltage to the electrode structure, switching between positive and negative voltages to control the ions, thereby separating different ions and allowing them to enter the reaction region separately, so that the controlled ions and the analyte undergo a chemical ionization reaction in the reaction region.

[0056] It should be noted that "controlling ions" refers to selecting ions, and "controlled ions" refers to the selected ions.

[0057] For example, such as Figure 1 As shown, the electrode structure 101 is an integral structure. The electrode structure 101 includes a hollow cylinder structure 101a and a sub-hollow cylinder structure 101b nested within the hollow cylinder structure 101a. The cavity of the hollow cylinder structure 101a is the cavity 1011 of the electrode structure 101, and the extension direction of the cavity 1011 is the first direction X. The region between the sidewall of the hollow cylinder structure 101a and the sidewall of the sub-hollow cylinder structure 101b is the ion generation region 1011a included in the cavity 1011. The region where the hollow cylinder structure 101a, the sub-hollow cylinder structure 101b, and the sample inlet tube 103 do not overlap is the reaction region 1011b included in the cavity 1011. In the reaction region 1011b, the analyte flowing in from the sample inlet tube 103 undergoes a chemical ionization reaction with the ions formed in the ion generation region 1011a, preparing for subsequent mass spectrometry detection.

[0058] For example, such as Figure 1 As shown, the end of the injection tube 103 located inside the cavity 1011 is closer to the reaction zone 1011b than the end of the sub-empty cylinder structure 101b near the reaction zone 1011b. That is, the right end of the sub-empty cylinder structure 101b in the first direction X is located to the left of the right end of the injection tube 103 in the first direction X. The end of the injection tube 103 extending into the cavity 1011 extends beyond the end of the sub-empty cylinder structure 101b near the reaction zone 1011b in the first direction X. Thus, under the push of the airflow, the ions generated in the ion generation zone 1011a can move to the right in the first direction X to the vicinity of the end of the injection tube 103 near the reaction zone 1011b, so that the analyte transmitted from the injection tube 103 can react with the ions when it leaves the injection tube 103.

[0059] For example, the distance between the end of the injection tube 103 located inside the cavity 1011 and the end of the sub-empty cylinder structure 101b near the reaction zone 1011b is 2mm to 8mm. For example, the distance between the end of the injection tube 103 located inside the cavity 1011 and the end of the sub-empty cylinder structure 101b near the reaction zone 1011b is 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, or 8mm.

[0060] For example, if the distance between the end of the injection tube 103 located inside the cavity 1011 and the end of the sub-empty cylinder structure 101b near the reaction zone 1011b is greater than 8 mm, the length of the reaction zone 1011b will be reduced, resulting in insufficient time for the analyte to react with the ions, leading to low reaction efficiency and the risk of affecting detection efficiency. Furthermore, because the extension length of the injection tube 103 inside the cavity 1011 is too long, some ions will adhere to the side wall of the injection tube 103 and will not be able to enter the reaction zone 1011b, thereby reducing the number of ions, reducing the application efficiency of ions, and further reducing the reaction efficiency. If the distance between the end of the injection tube 103 located inside the cavity 1011 and the end of the sub-empty cylinder structure 101b near the reaction zone 1011b is less than 2 mm, the amount of ions that do not reach the end of the injection tube 103 located inside the cavity 1011 or reach the end of the injection tube 103 located inside the cavity 1011 will be very small. As a result, the analyte transmitted from the injection tube 103 cannot react with sufficient ions immediately when it leaves the injection tube 103. It will only react with sufficient ions after moving a certain distance to the right in the first direction X. This will reduce the reaction efficiency.

[0061] For example, the injection tube 103 uses an injection flow rate greater than 10 L / min, which reduces the residence time of the analyte in the injection tube 103 and reduces the diffusion loss of the analyte.

[0062] For example, such as Figure 1 As shown, the cavity 1011 also includes a transition region 1011c between the ion generation region 1011a and the reaction region 1011b. That is, the cavity 1011 includes the ion generation region 1011a, the transition region 1011c, and the reaction region 1011b arranged sequentially in the first direction X. The sample inlet tube 103 extends from outside the cavity 1011 in the first direction X to the boundary between the transition region 1011c and the reaction region 1011b. For example, the area where the empty cylinder structure 101a does not overlap with the sub-empty cylinder structure 101b but overlaps with the sample inlet tube 103 is the transition region 1011c included in the cavity 1011.

[0063] For example, such as Figure 1As shown, for ions located in the upper part of cavity 1011, assuming that positive ions are required to enter reaction zone 1011b for reaction, since voltage controller 104 applies a positive voltage to electrode structure 101, and injection tube 103 is conductive and grounded with a voltage of 0V, positive ions will move from the high-voltage electrode structure 101 to the low-voltage injection tube 103, that is, move downwards. Negative ions will be repelled by the electric field onto electrode structure 101 and cannot react with the analyte. The direction of the airflow pushing the positive ions is the first direction X. Thus, the airflow and electric field simultaneously exert a force on the positive ions, causing the positive ions to be subjected to a force moving downwards and to the right. This is conducive to the positive ions moving towards the end of injection tube 103 located inside cavity 1011, so that the analyte and positive ions can react in time.

[0064] For example, for ions located in the upper part of the cavity 1011, if the end of the injection tube 103 located inside the cavity 1011 is on the left side of the end of the sub-cavity structure 101b near the reaction zone 1011b, assuming that positive ions need to react with the analyte, since the voltage controller 104 applies a positive voltage to the electrode structure 101, the injection tube 103 is conductive, and the voltage of the injection tube 103 is 0V when it is grounded, positive ions will move from the high-voltage electrode structure 101 to the low-voltage injection tube 103, that is, move downwards. Negative ions will be repelled by the electric field onto the electrode structure 101 and cannot react with the analyte. Thus, the direction of the airflow pushing positive ions is to the right, and the direction of the electric field pushing positive ions is downwards. As a result, the analyte transmitted from the injection tube 103 cannot react with ions immediately when it leaves the injection tube 103. It will only react with sufficient ions after the analyte moves a certain distance to the right in the first direction X. This will reduce the reaction efficiency.

[0065] For example, such as Figure 1 As shown, for ions located in the lower half of cavity 1011, assuming that positive ions are required to enter reaction zone 1011b for reaction, since voltage controller 104 applies a positive voltage to electrode structure 101, and injection tube 103 is conductive and grounded with a voltage of 0V, positive ions will move from the high-voltage electrode structure 101 to the low-voltage injection tube 103, i.e., upward. Negative ions will be repelled by the electric field onto electrode structure 101 and cannot react with the analyte. The direction of the airflow pushing the positive ions is the first direction X. Thus, the airflow and electric field simultaneously exert a force on the positive ions, causing the positive ions to be subjected to a force moving to the upper right. This is beneficial for the positive ions to move towards the end of injection tube 103 located inside cavity 1011, so that the analyte and positive ions can react in time.

[0066] For example, such as Figure 1As shown, for ions located in the upper part of cavity 1011, assuming that negative ions are needed to enter reaction zone 1011b for reaction, since the voltage controller 104 applies a negative voltage to electrode structure 101, and the injection tube 103 is conductive and grounded with a voltage of 0V, negative ions will move from the low-voltage electrode structure 101 to the high-voltage injection tube 103, that is, move downwards. Positive ions will be repelled by the electric field onto electrode structure 101 and cannot react with the analyte. The airflow pushes the negative ions in the first direction X. Thus, the airflow and electric field simultaneously exert a force on the negative ions, causing the negative ions to be subjected to a force moving downwards and to the right. This is conducive to the negative ions moving towards the end of the injection tube 103 located inside cavity 1011, so that the analyte and negative ions can react in time.

[0067] For example, such as Figure 1 As shown, for ions located in the lower half of cavity 1011, assuming that negative ions are needed to enter reaction zone 1011b for reaction, since the voltage controller 104 applies a negative voltage to the electrode structure 101, and the injection tube 103 is conductive and grounded with a voltage of 0V, the negative ions will move from the low-voltage electrode structure 101 to the high-voltage injection tube 103, that is, move upward. Positive ions will be repelled by the electric field onto the electrode structure 101 and cannot react with the analyte. The airflow pushes the negative ions in the first direction X. Thus, the airflow and electric field simultaneously exert a force on the negative ions, causing the negative ions to be subjected to a force moving upward and to the right. This is conducive to the negative ions moving towards the end of the injection tube 103 located inside cavity 1011, so that the analyte and negative ions can react in time.

[0068] It should be noted that in other examples, the injection tube may not be grounded, as long as there is a voltage difference between the injection tube and the electrode structure, positive or negative ions can be pushed to the end of the injection tube located in the cavity.

[0069] For example, in one example, the material of the electrode structure 101 is a conductive metal, such as copper, aluminum or silver.

[0070] For example, in one example, the material of the electrode structure 101 is a carbon-based conductive material, such as carbon rods, carbon nanotubes, or activated carbon.

[0071] For example, in one example, the material of the electrode structure 101 is a metal oxide or ceramic electrode, such as indium tin oxide, tin dioxide, or zinc oxide.

[0072] For example, in one example, the material of the electrode structure 101 is a material with gradually changing conductivity. For example, the material of the electrode structure 101 is polyaniline (PANI) or polypyrrole doped with insulating material. By adjusting the concentration of insulating material, the conductivity of different parts of the electrode structure 101 can be adjusted so that there is a voltage difference between different parts of an electrode structure 101.

[0073] For example, in one instance, the ions include both positive and negative ions, and the ion generator 102 is configured to simultaneously generate both positive and negative ions in the ion generation region. This ion generator is, for example, a soft X-ray source.

[0074] For example, such as Figure 1 As shown, the ionization source control device 100 also includes a rectifier screen 105, which is disposed between the reaction gas supply port 106 and the ion generator 102. For example, before the ion-generating gas that forms ions enters the ion generator 102, the ion-generating gas first passes through the rectifier screen 105 to be uniformly mixed and kept in a laminar flow state, thereby reducing gas turbulence and making the flow of the ion-generating gas smoother. This results in a more uniform concentration of formed ions in the ion generation area, maintaining the stability of the airflow within the atmospheric pressure chemical ionization source.

[0075] For example, the rectifier screen 105 is a structure that forms a complete ring between the reaction gas supply port 106 and the sample inlet tube 103. For example, in Figure 1 In the cross-sectional structure shown, for the rectifier screen 105 on the upper part of the sample inlet tube 103, it extends from a first position to a second position in a second direction Y that intersects with the first direction X. The first position is flush with the height of the inner edge of the empty cylinder structure in the second direction Y, and the second position is flush with the side wall of the sample inlet tube near the corresponding empty cylinder structure.

[0076] It should be noted that although some of the ion-generating gas enters the space between the side wall of the sub-vacuum tube structure and the sample inlet tube without being ionized, in the embodiments of this disclosure, it is not necessary for all the reaction gases to be converted into reaction ions. It is only necessary for the ion concentration to be uniform. Furthermore, since the unionized ion-generating gas does not react with ions, it will not interfere with the detection, because mass spectrometry detects charged ions formed after the reaction between the component to be detected in the air and ions.

[0077] For example, such as Figure 1 As shown, the ionization source control device 100 also includes a tail gas outlet 107. The electrode structure 101 extends in the first direction X to the side of the tail gas outlet 107 away from the sample inlet tube 103. This design can extend the reaction zone, allowing the ions and analytes to react more fully, and the products formed after the reaction preferentially enter the mass spectrometer mentioned later, avoiding the products being preferentially extracted.

[0078] For example, the pressure condition in the ionization source control device 100 is atmospheric pressure, which avoids gas turbulence caused by low pressure and sensitivity loss caused by dilution of the analyte.

[0079] For example, the reaction gas supply port 106 and the tail gas outlet 107 are both set as two symmetrical holes around the axis of the atmospheric pressure chemical ionization source, so that the airflow in the atmospheric pressure chemical ionization source is kept uniformly distributed.

[0080] For example, the ionization source control device used in the embodiments of this disclosure is an atmospheric pressure chemical ionization source structure, which has the versatility to be used with a variety of types of mass spectrometers.

[0081] For example, Figure 2 A cross-sectional structural schematic diagram of another ionization source control device provided in at least one embodiment of this disclosure, as shown below. Figure 2 As shown, the ionization source control device 100 includes: an electrode structure 101, an ion generator 102, a sample injection tube 103, and a voltage controller 104. The electrode structure 101 includes a cavity 1011, which includes an ion generation region 1011a and a reaction region 1011b. The electrode structure 101 includes a first electrode group 1012, which includes a first electrode structure 1012a and a second electrode structure 1012b arranged sequentially and insulated in the first direction X. The cavity 1011 extends in the first direction X. The ion generator 102 is configured to generate ions in the ion generation region 1011a. The voltage controller 104 is configured to simultaneously apply a positive voltage or a negative voltage to the first electrode structure 1012a and the second electrode structure 1012b, switching between the positive and negative voltages to control the ions. The sample inlet tube 103 is configured to allow the analyte flowing into the sample inlet tube 103 to undergo a chemical ionization reaction with the controlled ions in the reaction region 1011b. This ionization source control device can rely solely on the voltage controller to apply a positive or negative voltage to the electrode structures, switching between the positive and negative voltages to control the ions, thereby separating different ions and allowing them to enter the reaction region separately, so that the controlled ions and the analyte undergo a chemical ionization reaction in the reaction region.

[0082] It should be noted that "controlling ions" refers to selecting ions, and "controlled ions" refers to the selected ions.

[0083] For example, such as Figure 2 As shown, the first electrode structure 1012a and the second electrode structure 1012b are separated by an insulator 108, so that different positive voltages or different negative voltages can be applied to the first electrode structure 1012a and the second electrode structure 1012b.

[0084] For example, such as Figure 2 As shown, the first electrode structure 1012a includes a first hollow structure 201 and a second hollow structure 202 sleeved within the first hollow structure 201, with a portion of the sample inlet tube 103 residing in the second hollow structure 202. The second electrode structure 1012b includes a third hollow structure 203, the inner diameter of which is equal to the inner diameter of the first hollow structure 201. The cavities of the first hollow structure 201, the second hollow structure 202, and the third hollow structure 203 form the cavity 1011 of the electrode structure 101, with the cavity 1011 extending in the first direction X. Designing the inner diameter of the third hollow structure 203 to be equal to the inner diameter of the first hollow structure 201 reduces turbulence of ions and analytes flowing within the cavity 1011.

[0085] For example, such as Figure 2 As shown, the area between the sidewall of the first empty cylinder structure 201 and the sidewall of the second empty cylinder structure 202 is the ion generation region 1011a of the cavity 1011. The area where the first empty cylinder structure 201 and the third empty cylinder structure 203 do not overlap with the second empty cylinder structure 202 and the sample inlet tube 103 is the reaction region 1011b of the cavity 1011. In the reaction region 1011b, the analyte flowing in from the sample inlet tube 103 undergoes a chemical ionization reaction with the controlled ions formed in the ion generation region 1011a in the reaction region 1011b, in preparation for subsequent mass spectrometry detection.

[0086] For example, such as Figure 2 As shown, the end of the injection tube 103 located inside the cavity 1011 is closer to the reaction zone 1011b than the end of the second empty cylinder structure 202 near the reaction zone 1011b. That is, the right end of the second empty cylinder structure 202 in the first direction X is located to the left of the right end of the injection tube 103 in the first direction X. The end of the injection tube 103 extending into the cavity 1011 extends beyond the end of the second empty cylinder structure 202 near the reaction zone 1011b in the first direction X. Thus, under the push of the airflow, the ions generated in the ion generation zone 1011a can move to the right in the first direction X to the vicinity of the end of the injection tube 103 near the reaction zone 1011b, so that the analyte transmitted from the injection tube 103 can react with the ions when it leaves the injection tube 103.

[0087] For example, such as Figure 2 As shown, the distance between the end of the injection tube 103 located inside the cavity 1011 and the end of the second empty cylinder structure 202 near the reaction zone 1011b is 2mm to 8mm. For example, the distance between the end of the injection tube 103 located inside the cavity 1011 and the end of the second empty cylinder structure 202 near the reaction zone 1011b is 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, or 8mm.

[0088] For example, if the distance between the end of the injection tube 103 located inside the cavity 1011 and the end of the second empty cylinder structure 202 near the reaction zone 1011b is greater than 8 mm, the length of the reaction zone 1011b will be reduced, which may lead to low reaction efficiency. Furthermore, because the extension length of the injection tube 103 inside the cavity 1011 is too long, some ions may adhere to the side wall of the injection tube 103 and fail to enter the reaction zone 1011b, thereby reducing the number of ions, reducing the efficiency of ion application, and further reducing the reaction efficiency. If the distance between the end of the injection tube 103 located inside the cavity 1011 and the end of the second empty cylinder structure 202 near the reaction zone 1011b is less than 2 mm, the amount of ions that do not reach the end of the injection tube 103 located inside the cavity 1011 or reach the end of the injection tube 103 located inside the cavity 1011 will be very small. As a result, the analyte transmitted from the injection tube 103 cannot react with sufficient ions immediately when it leaves the injection tube 103. It will only react with sufficient ions after moving a certain distance to the right in the first direction X. This will reduce the reaction efficiency.

[0089] For example, such as Figure 2 As shown, the cavity 1011 also includes a transition region 1011c between the ion generation region 1011a and the reaction region 1011b. That is, the cavity 1011 includes the ion generation region 1011a, the transition region 1011c, and the reaction region 1011b arranged sequentially in the first direction X. The sample inlet tube 103 extends from outside the cavity 1011 in the first direction X to the boundary between the transition region 1011c and the reaction region 1011b. For example, the area where the first empty cylinder structure 201 does not overlap with the second empty cylinder structure 202, but overlaps with the sample inlet tube 103, is the transition region 1011c included in the cavity 1011.

[0090] For example, such as Figure 2As shown, for ions located in the upper half of cavity 1011, assuming positive ions are required to enter reaction zone 1011b for reaction, since voltage controller 104 applies positive voltages to both the first electrode structure 1012a and the second electrode structure 1012b, the positive voltage applied to the first electrode structure 1012a is greater than the positive voltage applied to the second electrode structure 1012b. The injection tube 103 is conductive, and its voltage is 0V when grounded. Positive ions will emerge from the higher voltage first electrode structure 1012a and the second electrode structure... 1012b moves towards the low-voltage injection tube 103, that is, downwards. The negative ions are repelled by the electric field to the first electrode structure 1012a and the second electrode structure 1012b, and cannot react with the analyte. The airflow pushes the positive ions in the first direction X. In this way, the airflow and the electric field simultaneously exert a force on the positive ions, so that the positive ions are subjected to a force that moves them to the right and downwards. This is conducive to the positive ions moving towards the end of the injection tube 103 located in the cavity 1011, so that the analyte and the positive ions can react in time.

[0091] For example, for ions located in the upper half of cavity 1011, if the end of injection tube 103 located inside cavity 1011 is located to the left of the end of the second empty cylinder structure 202 near the reaction zone 1011b, assuming that positive ions need to react with the analyte, since voltage controller 104 applies positive voltage to both the first electrode structure 1012a and the second electrode structure 1012b, the positive voltage applied to the first electrode structure 1012a is greater than the positive voltage applied to the second electrode structure 1012b. Injection tube 103 is conductive, and its voltage is 0V when grounded. Positive ions will flow from the high-voltage first electrode structure 1012a. When the first electrode structure 1012a and the second electrode structure 1012b move towards the low-voltage injection tube 103, i.e., downwards, the negative ions are repelled by the electric field and cannot react with the analyte. Thus, the gas flow pushes the positive ions to the right, and the electric field pushes the positive ions downwards. As a result, the analyte transported from the injection tube 103 cannot react with the ions immediately when it leaves the injection tube 103. It will only react with sufficient ions after the analyte has moved a certain distance to the right in the first direction X. This reduces the reaction efficiency.

[0092] For example, such as Figure 2As shown, for ions located in the lower half of cavity 1011, assuming positive ions are required to enter reaction zone 1011b for reaction, since voltage controller 104 applies positive voltages to both the first electrode structure 1012a and the second electrode structure 1012b, the positive voltage applied to the first electrode structure 1012a is greater than the positive voltage applied to the second electrode structure 1012b. The injection tube 103 is conductive, and its voltage is 0V when grounded. Positive ions will emerge from the higher voltage first electrode structure 1012a and the second electrode structure... 1012b moves towards the low-voltage injection tube 103, that is, upwards. The negative ions are repelled by the electric field to the first electrode structure 1012a and the second electrode structure 1012b, and cannot react with the analyte. The airflow pushes the positive ions in the first direction X. In this way, the airflow and the electric field simultaneously exert a force on the positive ions, so that the positive ions are subjected to a force that moves to the upper right. This is conducive to the positive ions moving towards the end of the injection tube 103 located in the cavity 1011, so that the analyte and the positive ions can react in time.

[0093] For example, such as Figure 2 As shown, for ions located in the upper half of cavity 1011, assuming negative ions are needed to enter reaction zone 1011b for reaction, since voltage controller 104 applies negative voltage to both the first electrode structure 1012a and the second electrode structure 1012b, the negative voltage applied to the first electrode structure 1012a is greater than the negative voltage applied to the second electrode structure 1012b. The injection tube 103 is conductive, and its voltage is 0V when grounded. Therefore, negative ions will flow from the negatively voltaged first electrode structure 1012a and the second electrode structure 1011b. 1012b moves towards the 0V injection tube 103, that is, downwards. Positive ions are repelled by the electric field to the first electrode structure 1012a and the second electrode structure 1012b, and cannot react with the analyte. The airflow pushes the negative ions in the first direction X. In this way, the airflow and the electric field simultaneously exert a force on the negative ions, so that the negative ions are subjected to a force that moves them to the right and downwards. This is conducive to the negative ions moving towards the end of the injection tube 103 located in the cavity 1011, so that the analyte and the negative ions can react in time.

[0094] For example, such as Figure 2As shown, for ions located in the lower half of cavity 1011, assuming negative ions are needed to enter reaction zone 1011b for reaction, since voltage controller 104 applies negative voltage to both the first electrode structure 1012a and the second electrode structure 1012b, the negative voltage applied to the first electrode structure 1012a is greater than the negative voltage applied to the second electrode structure 1012b. The injection tube 103 is conductive, and its voltage is 0V when grounded. Therefore, negative ions will flow from the negatively voltaged first electrode structure 1012a and the second electrode structure 1011b. 1012b moves towards the 0V injection tube 103, that is, upwards. Positive ions are repelled by the electric field to the first electrode structure 1012a and the second electrode structure 1012b, and cannot react with the analyte. The airflow pushes the negative ions in the first direction X. In this way, the airflow and the electric field simultaneously exert a force on the negative ions, so that the negative ions are subjected to a force that moves them to the upper right. This is conducive to the negative ions moving towards the end of the injection tube 103 located in the cavity 1011, so that the analyte and the negative ions can react in time.

[0095] It should be noted that in other examples, the injection tube may not be grounded. As long as there is a voltage difference between the injection tube and the first electrode structure 1012a and the second electrode structure 1012b, positive or negative ions can be pushed to the end of the injection tube located in the cavity.

[0096] For example, Figure 3 for Figure 2 Block diagram of the medium voltage controller. Figure 4 for Figure 2 A schematic diagram illustrating the implementation of the voltage controller switching between positive and negative voltages, combined with... Figure 2 , Figure 3 and Figure 4 As shown, the voltage controller 104 includes a first DC power supply 1041, a time relay 1042 and a switch 1043 connected in sequence, and a second DC power supply 1044 connected to the time relay 1042.

[0097] For example, such as Figure 2 , Figure 3 and Figure 4 As shown, the first DC power supply 1041 is configured to simultaneously provide a positive voltage or simultaneously provide a negative voltage to the first electrode structure 1012a and the second electrode structure 1012b. The second DC power supply 1044 is configured to provide a pulse voltage signal to the time relay 1042 to control the time relay 1042 to open and close. The time relay 1042 is configured to switch the connection contacts of the first and second terminals of the control switch 1043 by opening and closing it, thereby realizing the switching of simultaneously applying a positive voltage to the first electrode structure 1012a and the second electrode structure 1012b and simultaneously applying a negative voltage.

[0098] For example, such as Figure 2 , Figure 3 and Figure 4 As shown, the time relay 1042 is configured to control the first terminal of the switch 1043 to be connected to the first electrode structure 1012a and the second electrode structure 1012b, and the second terminal to be connected to the sample injection tube 103; or, the time relay 1042 is configured to control the first terminal of the switch 1043 to be connected to the sample injection tube 103, and the second terminal to be connected to the first electrode structure 1012a and the second electrode structure 1012b.

[0099] For example, such as Figure 2 , Figure 3 and Figure 4 As shown, the first terminal of switch 1043 is configured to connect to the first electrode structure 1012a and the second electrode structure 1012b, and the second terminal of switch 1043 is configured to connect to the sample injection tube 103, so as to apply a positive voltage to the first electrode structure 1012a and the second electrode structure 1012b simultaneously; or, the first terminal of switch 1043 is configured to connect to the sample injection tube 103, and the second terminal of switch 1043 is configured to connect to the first electrode structure 1012a and the second electrode structure 1012b, so as to apply a negative voltage to the first electrode structure 1012a and the second electrode structure 1012b simultaneously.

[0100] For example, the time relay 1042 controls the duration of the positive or negative voltage applied to the first electrode structure 1012a and the second electrode structure 1012b. The switching frequency can be set by adjusting the duration. For example, setting it to 2 minutes means that the positive or negative ion is switched every two minutes for measurement.

[0101] For example, in one example, the switch is a double-pole double-throw switch.

[0102] In summary, the voltage switching method is as follows: a 6~24V pulse voltage signal is provided to the time relay 1042 by the second DC power supply 1044 to control its opening and closing. The double-pole double-throw switch switches its contacts in real time with the opening and closing of the time relay 1042, thereby outputting the voltage provided by the second DC power supply 1044 in either the forward or reverse direction. That is, the voltage switching only involves the switching of the DC voltage applied to the electrode structure. The switching only changes the voltage polarity and does not change the absolute value of the voltage. In other words, this switching method does not involve the gradual increase or decrease of the voltage magnitude, but only needs to change the voltage polarity. Therefore, the switching speed is very fast, and the switching time is less than or equal to 0.1 s.

[0103] In the embodiments disclosed herein, only a small DC power supply is needed to provide a DC voltage of about 100 volts and miniature electronic components such as switches to switch between positive and negative voltages. The function of selecting positive and negative reactive ions can be realized by relying on DC voltage drive. It has the advantages of simple device structure, strong operability, low cost and portability.

[0104] Benefiting from the extremely fast switching speed between positive and negative voltages, the atmospheric pressure chemical ionization source in the embodiments of this disclosure can efficiently and rapidly switch between positive and negative ions. Traditional methods for switching reactive ions generally involve alternately introducing specific reactive gases to sequentially generate different reactive ions. Neutral reactive gases often leave residues within the ionization source, leading to a memory effect, especially for highly viscous gases such as nitric acid and diethylamine, where the memory effect is more severe. The embodiments of this disclosure employ a positive and negative voltage switching method, allowing the two reactive gases to mix and simultaneously enter the ionization source. This eliminates the need to switch reactive gases, achieving rapid switching between positive and negative ions and avoiding the memory effect interference caused by reactive gas switching. Experimental results show that this method of switching voltage polarity can completely remove ions of opposite polarity from the ionization source; for example, no interference from negative ions is present during positive ion mode detection.

[0105] For example, in one instance, the difference between the positive voltages simultaneously applied to the first electrode structure 1012a and the second electrode structure 1012b is greater than or equal to a first threshold, for example, the first threshold being 10V. Similarly, the difference between the negative voltages simultaneously applied to the first electrode structure 1012a and the second electrode structure 1012b is greater than or equal to a second threshold, for example, the second threshold being 10V. This voltage difference design allows for more efficient aggregation of target ions into the reaction region, thereby improving reaction efficiency and detection efficiency.

[0106] It should be noted that although the difference in positive voltage applied simultaneously to the first and second electrode structures can be less than 10V, this will result in insufficient ions reaching the reaction region, reducing reaction efficiency and significantly decreasing the signal intensity of the product ions detected by the mass spectrometer. For example, within the allowable error range, it can also be less than 10V, such as 9.5V, 9.6V, 9.7V, 9.8V, or 9.9V.

[0107] For example, in one instance, a positive voltage of +125V is applied to the first electrode structure 1012a and a positive voltage of +110V is applied to the second electrode structure 1012b; or a negative voltage of -125V is applied to the first electrode structure 1012a and a negative voltage of -110V is applied to the second electrode structure 1012b, so that the target single ion efficiently converges towards the center to react with the analyte, while non-target ions are repelled to the first electrode structure 1012a or the second electrode structure 1012b for removal, and a sufficient number of ions reach the reaction zone to improve reaction efficiency. However, the embodiments disclosed herein are not limited thereto. The positive voltage applied to the first electrode structure 1012a can be +120V to +130V, and the positive voltage applied to the second electrode structure 1012b can be +105V to +115V; or the negative voltage applied to the first electrode structure 1012a can be -120V to -130V, and the negative voltage applied to the second electrode structure 1012b can be -105V to -115V.

[0108] For example, the materials of the first electrode structure 1012a and the second electrode structure 1012b can be conductive metals, such as copper, aluminum or silver; or they can be carbon-based conductive materials, such as carbon rods, carbon nanotubes or activated carbon; or they can be metal oxides or ceramic electrodes, such as indium tin oxide, tin dioxide or zinc oxide. The embodiments disclosed herein do not limit these materials.

[0109] For example, such as Figure 2 As shown, the ionization source control device 100 also includes a rectifier screen 105, which is disposed between the reaction gas supply port 106 and the ion generator 102. For example, before the ion-generating gas that forms ions enters the ion generator 102, the ion-generating gas first passes through the rectifier screen 105 to be uniformly mixed and kept in a laminar flow state, thereby reducing gas turbulence and making the flow of the ion-generating gas smoother. This results in a more uniform concentration of formed ions in the ion generation area, maintaining the stability of the airflow within the atmospheric pressure chemical ionization source.

[0110] For example, the rectifier screen 105 is a structure that forms a complete ring between the reaction gas supply port 106 and the sample inlet tube 103. For example, in Figure 2 In the cross-sectional structure shown, for the rectifier screen 105 on the upper part of the sample inlet tube 103, it extends from a first position to a second position in a second direction Y that intersects with the first direction X. The first position is flush with the height of the edge of the first empty cylinder structure in the second direction Y, and the second position is flush with the side wall of the sample inlet tube near the corresponding second empty cylinder structure.

[0111] It should be noted that although some of the ion-generating gas enters the space between the side wall of the second empty cylinder structure and the sample inlet tube without being ionized, in the embodiments of this disclosure, it is not necessary for all the reaction gases to be converted into reaction ions. It is only necessary for the ion concentration to be uniform. Furthermore, since the unionized ion-generating gas does not react with ions, it will not interfere with the detection, because mass spectrometry detects charged ions formed after the reaction between the component to be detected in the air and ions.

[0112] For example, such as Figure 2 As shown, the ionization source control device 100 also includes a tail gas outlet 107. The electrode structure 101 extends in the first direction X to the side of the tail gas outlet 107 away from the sample inlet tube 103. This design can extend the reaction zone, allowing the ions and analytes to react more fully, and the products formed after the reaction preferentially enter the mass spectrometer mentioned later, avoiding the products being preferentially extracted.

[0113] For example, the reaction gas supply port 106 and the tail gas outlet 107 are both set as two symmetrical holes around the axis of the atmospheric pressure chemical ionization source, so that the airflow in the atmospheric pressure chemical ionization source is kept uniformly distributed.

[0114] For example, the atmospheric pressure chemical ionization source structure used in the embodiments of this disclosure has the versatility to be used with a variety of types of mass spectrometers.

[0115] For example, Figure 5 This is a cross-sectional structural schematic diagram of another ionization source control device provided in at least one embodiment of the present disclosure. Figure 5 The ionization source control device shown and Figure 2 The difference in the ionization source control device shown is that: Figure 5 The ionization source control device 100 shown also includes a reaction gas supply component 300, which includes a protective gas supply unit 301, a first gas supply unit 302, a second gas supply unit 303, and a zero air supply unit 304 connected in sequence. The protective gas supply unit 301 is configured to provide protective gas, the first gas supply unit 302 is configured to provide gas for forming negative ions, the second gas supply unit 303 is configured to provide gas for forming positive ions, and the zero air supply unit 304 is configured to provide purified air.

[0116] For example, the reaction gas supply component 300 is used to provide two reaction gases, nitric acid and diethylamine, and the reaction gas supply component 300 is connected to the reaction gas supply port 106 through a gas passage.

[0117] For example, the protective gas supply unit 301 is used to supply protective gases such as nitrogen and helium. The first gas supply unit 302 is configured to generate nitric acid vapor to form negative ions. The second gas supply unit 303 is configured to generate diethylamine vapor to form positive ions.

[0118] The following explanation uses the example of a protective gas supply unit 301 supplying nitrogen, a first gas supply unit 302 supplying nitric acid vapor, a second gas supply unit 303 supplying diethylamine vapor, and a zero-air supply unit 304 supplying purified air. The protective gas supply unit 301 generates a small flow of nitrogen, which flows sequentially through the first gas supply unit 302 and the second gas supply unit 303. The first gas supply unit 302 and the second gas supply unit 303 respectively use test tubes containing concentrated nitric acid liquid and pure diethylamine liquid. Nitric acid vapor and diethylamine vapor are generated through the free evaporation of the liquids. The nitrogen, carrying the evaporated nitric acid vapor and diethylamine vapor, mixes and dilutes with the large flow of purified air generated by the zero-air supply unit 304 before entering the chamber 1011 through the reaction gas supply port 106.

[0119] For example, the second gas supply unit 303 also includes a Teflon gasket placed at the top of the test tube containing pure diethylamine liquid to limit the evaporation rate of diethylamine vapor so that the concentrations of the evaporating nitric acid vapor and diethylamine vapor are matched.

[0120] For example, the flow rate of nitrogen supplied by the protective gas supply unit 301 is less than 10 mL / min, and the flow rate of purified air supplied by the zero air supply unit is greater than 20 L / min, so as to ensure that the reaction gas is sufficiently diluted to a low concentration, that is, the flow rate of zero air is much greater than the flow rate of nitrogen to fully dilute nitric acid vapor and diethylamine vapor.

[0121] Figure 5 Other structures in the ionization source control device shown can be found in the above description. Figure 2 The description of the ionization source control device shown will not be repeated here.

[0122] Figure 6 A cross-sectional structural schematic diagram of another ionization source control device provided in at least one embodiment of this disclosure, as shown below. Figure 6 As shown, in Figure 2 Based on the structure of the ionization source control device shown, the electrode structure 101 further includes a second electrode group 1013. The first electrode group 1012 and the second electrode group 1013 are sequentially arranged and insulated in the first direction X. The second electrode group 1013 includes a third electrode structure 1013a and a fourth electrode structure 1013b sequentially arranged and insulated in the first direction X. The first electrode structure 1012a and the second electrode structure 1012b are separated by an insulator 108, the second electrode structure 1012b and the third electrode structure 1013a are separated by an insulator 108, and the third electrode structure 1013a and the fourth electrode structure 1013b are separated by an insulator 108.

[0123] For example, such as Figure 6As shown, the first electrode structure 1012a includes a first hollow structure 201 and a second hollow structure 202 sleeved within the first hollow structure 201, with a portion of the sample inlet tube 103 residing in the second hollow structure 202. The second electrode structure 1012b includes a third hollow structure 203. The third electrode structure 1013a includes a fourth hollow structure 204, and the fourth electrode structure 1013b includes a fifth hollow structure 205. The cavities of the first hollow structure 201, second hollow structure 202, third hollow structure 203, fourth hollow structure 204, and fifth hollow structure 205 form the cavity 1011 of the electrode structure 101, with the cavity 1011 extending in the first direction X. The inner diameters of the first hollow structure 201, third hollow structure 203, fourth hollow structure 204, and fifth hollow structure 205 are equal, which can reduce turbulence of ions and analytes flowing in the cavity 1011.

[0124] For example, such as Figure 6 As shown, a portion of the injection tube 103 is in the second empty cylinder structure 202, and the end of the injection tube 103 located in the cavity 1011 is closer to the reaction zone 1011b than the end of the second empty cylinder structure 202 that is closer to the reaction zone 1011b. The end of the injection tube 103 located in the cavity 1011 is in the third empty cylinder structure 203.

[0125] For example, combining Figure 6 , Figure 3 and Figure 4 The first DC power supply is configured to simultaneously provide a positive voltage or simultaneously provide a negative voltage to at least two of the first electrode structure 1012a, the second electrode structure 1012b, the third electrode structure 1013a, and the fourth electrode structure 1013b. The second DC power supply is configured to provide a pulse voltage signal to the time relay to control the time relay to open and close. The time relay is configured to control the switching of the connection contacts of the first and second terminals of the switch by opening and closing, so as to realize the switching of simultaneously applying a positive voltage and simultaneously applying a negative voltage to at least two of the first electrode structure 1012a, the second electrode structure 1012b, the third electrode structure 1013a, and the fourth electrode structure 1013b.

[0126] For example, in one example, a gradually decreasing positive voltage or a gradually decreasing negative voltage is simultaneously applied to the first electrode structure 1012a, the second electrode structure 1012b, the third electrode structure 1013a, and the fourth electrode structure 1013b, and the difference between the positive voltages simultaneously applied to any two adjacent electrode structures is greater than or equal to a third threshold, for example, the third threshold is 5V; the difference between the negative voltages simultaneously applied to any two adjacent electrode structures is greater than or equal to a fourth threshold, for example, the fourth threshold is 5V. For example, within the allowable error range, it can also be less than 5V, for example, 4.5V, 4.6V, 4.7V, 4.8V, or 4.9V, etc.

[0127] For example, in one instance, a positive voltage of +135V is applied to the first electrode structure, a positive voltage of +123V is applied to the second electrode structure, a positive voltage of +111V is applied to the third electrode structure, and a positive voltage of +90V is applied to the fourth electrode structure; or a negative voltage of -135V is applied to the first electrode structure, a negative voltage of -123V is applied to the second electrode structure, a negative voltage of -111V is applied to the third electrode structure, and a negative voltage of -90V is applied to the fourth electrode structure. However, the embodiments disclosed herein are not limited to this. The positive voltage applied to the first electrode structure is +130V to +140V, the positive voltage applied to the second electrode structure is +118V to +128V, the positive voltage applied to the third electrode structure is +106V to +117V, and the positive voltage applied to the fourth electrode structure is +85V to +95V; or the negative voltage applied to the first electrode structure is -130V to -140V, the negative voltage applied to the second electrode structure is -118V to -128V, the negative voltage applied to the third electrode structure is -106V to -117V, and the negative voltage applied to the fourth electrode structure is -85V to -95V.

[0128] It should be noted that, although Figure 6 Only one second electrode group is shown in the figure. In other structures, more second electrode groups can be designed. The embodiments disclosed herein are not limited to this.

[0129] It should also be noted that, for Figure 6The description uses the simultaneous application of positive or negative voltages to the first, second, third, and fourth electrode structures as an example. However, the embodiments of this disclosure are not limited to this. Alternatively, positive or negative voltages may be applied simultaneously to the first, second, and third electrode structures, while no voltage is applied to the fourth electrode structure; or, positive or negative voltages may be applied simultaneously to the first, third, and fourth electrode structures, while no voltage is applied to the second electrode structure; or, positive or negative voltages may be applied simultaneously to the first, second, and fourth electrode structures, while no voltage is applied to the third electrode structure. Alternatively, a positive voltage or a negative voltage may be applied simultaneously to the first and third electrode structures, while no voltage is applied to the second and fourth electrode structures; or a positive voltage or a negative voltage may be applied simultaneously to the first and fourth electrode structures, while no voltage is applied to the second and third electrode structures; or a positive voltage or a negative voltage may be applied simultaneously to the second and third electrode structures, while no voltage is applied to the first and fourth electrode structures; or a positive voltage or a negative voltage may be applied simultaneously to the second and fourth electrode structures, while no voltage is applied to the first and third electrode structures. The embodiments of this disclosure do not limit this to any particular type of voltage application.

[0130] It should be noted that in other examples, an electrode structure may have a gradually decreasing voltage along its length when a voltage is applied to it due to its material properties. Alternatively, two adjacent electrode structures may not be insulated from each other, and a resistor may be added between the two adjacent electrode structures so that when a voltage is applied to one electrode structure, the voltage on the two adjacent electrode structures decreases.

[0131] At least one embodiment of this disclosure also provides a mass spectrometer detection system, which includes: an ionization source control device as described in any of the above embodiments and a mass spectrometer connected to the ionization source control device. The mass spectrometer detection system can simultaneously generate positive and negative ions, and switch between positive and negative ions by voltage regulation alone. Furthermore, the ionization source control device is coupled to a mass spectrometer detector (such as an orbital trap mass spectrometer) with the ability to quickly switch between positive and negative modes. The mass spectrometer detection system can achieve more comprehensive molecular recognition of oxygen-containing organic molecules in the atmosphere.

[0132] For example, Figure 7 This is a schematic cross-sectional view of a mass spectrometer detection system provided in at least one embodiment of the present disclosure, combined with... Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 7As shown, the mass spectrometer detection system 500 includes: an ionization source control device 100 as described in any of the above embodiments and a mass spectrometer 400 connected to the ionization source control device. The relevant structure of the ionization source control device 100 can be found in the relevant description above, and will not be repeated here.

[0133] For example, such as Figure 7 As shown, the mass spectrometer 400 includes a mass spectrometry sampling cone 401 and an orbital trap mass spectrometry detector 402. The axis EF of the mass spectrometry sampling cone 401 in the first direction X coincides with the axis GH of the sample inlet tube 103 in the first direction X. This allows the analyte that has completed the reaction to directly enter the mass spectrometry sampling cone, thereby improving the efficiency of mass spectrometry detection.

[0134] For example, in one example, the mass spectrometer sampling cone 401 draws in the synthesized ions generated in the reaction zone 1011b through negative pressure aspiration and transmits them to the orbital trap mass spectrometer detector 402, and the orbital trap mass spectrometer detector 402 switches between positive mode detection and negative mode detection according to the time synchronization of the positive and negative synthesized ions generated in the reaction zone 1011b.

[0135] For example, in one instance, the flow rate of the mass spectrometer sampling cone under negative pressure is 1.2 L / min ~ 2.2 L / min.

[0136] For example, in one instance, the flow rate of the mass spectrometer sampling cone under negative pressure is 1.8 L / min.

[0137] For example, in one example, the switching frequency of positive mode detection and negative mode detection set by the orbital trap mass spectrometer detector 402 is consistent with the switching frequency of positive voltage and negative voltage set by the time relay 1042 included in the voltage controller 104. This design can ensure that the switching of positive detection mode and negative detection mode of the orbital trap mass spectrometer detector 402 is completely synchronized with the switching of positive ion and negative ion of the ionization source control device 100, so as to improve the efficiency of mass spectrometry analysis.

[0138] For example, when the ionization source control device uses positive ion measurement, the orbital trap mass spectrometer detector 402 needs to maintain positive mode detection; when the ionization source control device uses negative ion measurement, the orbital trap mass spectrometer detector 402 needs to maintain negative mode detection.

[0139] For example, in one instance, the switching frequency between positive and negative mode detection of the orbital trap mass spectrometer is 1.2 Hz to 2.1 Hz, and the switching time between the positive and negative voltages set by the time relay is less than or equal to 0.1 s.

[0140] For example, in one instance, the switching frequency between positive and negative mode detection of the orbital trap mass spectrometer is 1.6 Hz, and the switching time between the positive and negative voltages set by the time relay is less than or equal to 0.1 s.

[0141] At least one embodiment of this disclosure also provides an ionization source control method, which includes: forming ions in an ion generation region, wherein the ion generation region is an ion generation region in a cavity included in an electrode structure; applying a positive voltage or a negative voltage to the electrode structure, switching the positive voltage and the negative voltage to control the ions; and causing the analyte flowing in through the injection tube to undergo a chemical ionization reaction with the controlled ions in a reaction region, wherein the reaction region is a reaction region in a cavity included in the electrode structure. This ionization source control method can achieve ion control by applying a positive voltage or a negative voltage to the electrode structure using a voltage controller, switching the positive voltage and the negative voltage to separate different ions, allowing different ions to enter the reaction region respectively, so that the controlled ions and the analyte undergo a chemical ionization reaction in the reaction region. This ionization source control method is simple to operate and has low equipment cost requirements.

[0142] For example, Figure 8 A flowchart illustrating at least one embodiment of an ionization source control method provided in this disclosure is shown below. Figure 8 As shown, the ionization source control method includes:

[0143] Step S101: Form ions in the ion generation region, wherein the ion generation region is the ion generation region in the cavity included in the electrode structure;

[0144] Step S102: Apply a positive voltage or a negative voltage to the electrode structure, and switch between positive and negative voltages to control the ions;

[0145] Step S103: The analyte flowing in through the injection tube undergoes a chemical ionization reaction with the controlled ions in the reaction zone, wherein the reaction zone is the reaction zone in the cavity included in the electrode structure.

[0146] For example, using Figure 8 The ionization source control method shown can achieve the control of ions by applying a positive or negative voltage to the electrode structure using only a voltage controller, switching between positive and negative voltages to separate different ions, and then allowing different ions to enter the reaction zone respectively, so that the controlled ions and the analyte can undergo a chemical ionization reaction in the reaction zone. This ionization source control method is simple to operate and has low equipment cost requirements.

[0147] For example, in one instance, ion formation in the ion-generating region includes the simultaneous formation of positive and negative ions.

[0148] For example, in one example, the simultaneous formation of positive and negative ions includes: providing a positive ion reaction gas and a negative ion reaction gas, passing a mixture of the positive and negative ion reaction gas into an ion generation region, and forming positive and negative ions in the ion generation region under the action of an ion generator (e.g., soft X-ray irradiation) on the mixture of the positive and negative ion reaction gas by an ion generator included in an ionization source control device.

[0149] For example, in one example, the positive ion reaction gas is nitric acid vapor, the negative ion reaction gas is diethylamine vapor, the positive ion is diethylamine cation, and the negative ion is nitrate ion. However, the embodiments of this disclosure are not limited to this, and the positive ion and the negative ion can be other ions respectively.

[0150] For example, C4H is selected in the embodiments of this disclosure. 12 N + and NO3 - The combination of two ions enables the detection of organic molecules across a wide volatility range, including low, medium, and high oxidation states. This is particularly relevant for molecules that generate C4H… 12 N + and NO3 - The mixture of the two reactive ions requires a specialized gas path design to ensure that the mixing ratio of diethylamine vapor and nitric acid vapor reaches an equilibrium value, preventing the concentration of one reactive ion from being too high and inhibiting the other reactive ion, and ultimately achieving the optimal ratio of the two reactive ions.

[0151] For example, in one instance, providing positive and negative ion reaction gases involves sequentially providing nitrogen, concentrated nitric acid liquid, diethylamine liquid, and zero air, with nitric acid vapor and diethylamine vapor formed by liquid evaporation; the nitrogen carrying the nitric acid vapor and diethylamine vapor is mixed and diluted with the zero air before entering the ion generation zone.

[0152] For example, in one instance, providing positive and negative ion reactant gases includes: sequentially providing a nitrogen supply unit, a nitric acid vapor generating unit, a diethylamine vapor generating unit, and a zero-air supply unit; the nitrogen supply unit generates nitrogen gas, which flows sequentially through the nitric acid vapor generating unit and the diethylamine vapor generating unit, the nitric acid vapor generating unit providing concentrated nitric acid liquid, and the diethylamine vapor generating unit providing diethylamine liquid, forming nitric acid vapor and diethylamine vapor through liquid evaporation; the nitrogen gas carrying the nitric acid vapor and diethylamine vapor mixes and dilutes with the zero air generated by the zero-air supply unit before entering the ion generation zone.

[0153] For example, in one instance, the ionization source control method further includes placing a flow regulating shim on top of the diethylamine vapor generating unit to control the volatilization rate of the diethylamine vapor so that the nitric acid vapor and diethylamine vapor achieve an optimal ratio.

[0154] Producing a suitable mixture of two reactant gases is a prerequisite for achieving efficient switching measurement of the two reactant ions. The simultaneous presence of the two reactant gases inevitably leads to a competitive effect; for example, excessively high diethylamine vapor content significantly inhibits the generation of nitrate anions. The evaporation rate of liquid diethylamine is nearly 40 times higher than that of concentrated nitric acid. To limit the evaporation of diethylamine vapor, a Teflon gasket of a certain density is placed at the top of the test tube, restricting its evaporation. This means that diethylamine vapor can only diffuse into the nitrogen carrier gas through the gaps in the Teflon gasket. This design effectively controls the ratio of nitric acid vapor to diethylamine vapor, thereby enabling the efficient switching measurement of C4H... 12 N + and NO3 - Both ions can be generated at high intensity. After parameter optimization, the volatilization rate of diethylamine was controlled at 0.4 μmol / min, while the volatilization rate of nitric acid was approximately 1.4 μmol / min.

[0155] For example, the equipment and methods for generating nitric acid vapor and diethylamine vapor can be found in the above-mentioned... Figure 5 The relevant descriptions will not be repeated here.

[0156] For example, in one example, the electrode structure includes a first electrode group, which includes a first electrode structure and a second electrode structure arranged sequentially and insulated in a first direction, and a cavity extending in the first direction; applying a positive voltage or a negative voltage to the electrode structures, and switching between the positive and negative voltages to control the ions includes: applying a first positive voltage and a second positive voltage to the first electrode structure and the second electrode structure respectively in a first time period to select the positive ions; and applying a first negative voltage and a second negative voltage to the first electrode structure and the second electrode structure respectively in a second time period to select the negative ions, so as to achieve switching between positive ions and negative ions in adjacent first and second time periods.

[0157] For example, the features and effects of the first electrode structure and the second electrode structure can be found in the above description. Figure 2 The relevant descriptions of the embodiments shown will not be repeated here.

[0158] For example, in one embodiment, the ionization source control device includes a voltage controller, which includes a first DC power supply, a time relay, and a switch connected in sequence, and a second DC power supply connected to the time relay. The switching between positive and negative ions includes: the first DC power supply simultaneously providing a positive voltage or simultaneously providing a negative voltage to a first electrode structure and a second electrode structure; the second DC power supply providing a pulse voltage signal to the time relay to control the time relay to open and close; and the time relay switching the connection contacts of the first and second terminals of the switch by opening and closing, thereby switching between simultaneously applying a positive voltage and simultaneously applying a negative voltage to the first and second electrode structures.

[0159] For example, in one example, the injection tube is conductive, the first end of the time relay control switch is connected to the first electrode structure and the second electrode structure, and the second end is connected to the injection tube; or, the first end of the time relay control switch is connected to the injection tube, and the second end is connected to both the first electrode structure and the second electrode structure.

[0160] For example, in one example, the first end of the switch is connected to the first electrode structure and the second electrode structure, and the second end of the switch is connected to the injection tube, so as to apply a positive voltage to the first electrode structure and the second electrode structure simultaneously; or, the first end of the switch is connected to the injection tube, and the second end of the switch is connected to the first electrode structure and the second electrode structure, so as to apply a negative voltage to the first electrode structure and the second electrode structure simultaneously.

[0161] For example, the features and effects of each structure in this voltage controller can be found in the above description. Figure 2 The relevant descriptions of the embodiments shown will not be repeated here.

[0162] For example, in one instance, the voltage controller applies a positive voltage or a negative voltage simultaneously to the first electrode structure and the second electrode structure, controlling the switching between positive and negative voltages to switch between positive and negative ions.

[0163] For example, in one instance, the voltage difference between the first positive voltage and the second positive voltage is greater than or equal to a first threshold, for example, the first threshold is 10V, and the voltage difference between the first negative voltage and the second negative voltage is greater than or equal to a second threshold, for example, the second threshold is 10V.

[0164] For example, in one example, a first positive voltage of +125V is applied to the first electrode structure and a second positive voltage of +110V is applied to the second electrode structure; or, a first negative voltage of -125V is applied to the first electrode structure and a second negative voltage of -110V is applied to the second electrode structure.

[0165] At least one embodiment of this disclosure also provides a mass spectrometer detection method, which includes: providing an ionization source control device and a mass spectrometer connected to the ionization source control device. The mass spectrometer includes a mass sampling cone and an orbital trap mass spectrometer detector. The mass sampling cone draws in ions generated in the reaction zone through negative pressure aspiration and transmits them to the orbital trap mass spectrometer detector. The orbital trap mass spectrometer detector synchronously switches between positive mode detection and negative mode detection according to the time of positive and negative reaction ions generated in the reaction zone.

[0166] For example, with a flow rate of 24 L / min for the carrier gas and 10 L / min for the analyte, the high gas flow rate means that the entire process from ion generation to reaction with the analyte and detection by the mass spectrometer takes only 0.4 s. This short residence time allows for rapid response to voltage switching. Simultaneously, the shortest time required for a single switch between positive and negative mode detection in the orbital trap mass spectrometer system is 0.6 s. In summary, the ionization source control device and the mass spectrometer can respond to voltage switching on a timescale of seconds. Their combined use is fundamental to achieving rapid selection of positive and negative ion modes based on voltage switching for detection.

[0167] For example, in one instance, the flow rate of the mass spectrometer sampling cone under negative pressure is 1.8 L / min.

[0168] For example, in one instance, the switching frequency of the positive mode detection and negative mode detection of the orbital trap mass spectrometer detector is consistent with the switching frequency of the positive and negative voltages of the time relays included in the voltage controller.

[0169] For example, in one instance, the switching frequency between positive and negative mode detection of the orbital trap mass spectrometer is 1.6 Hz, and the switching time between the positive and negative voltages set by the time relay is less than or equal to 0.1 s.

[0170] The ionization source control device, ionization source control method, mass spectrometer detection system, and mass spectrometer detection method provided in at least one embodiment of this disclosure have at least the following technical effects: they can rely solely on a voltage controller to apply a positive voltage or a negative voltage to the electrode structure, and switch between positive and negative voltages to control ions and separate different ions; the ionization source control device used in the embodiments of this disclosure is an atmospheric pressure chemical ionization source structure, which has the versatility to be used with various types of mass spectrometers.

[0171] The following points need to be explained:

[0172] (1) The accompanying drawings of the embodiments of this disclosure only involve the structures involved in the embodiments of this disclosure. Other structures can be referred to the general design.

[0173] (2) For clarity, the thickness of layers or regions in the drawings used to describe embodiments of the present disclosure is enlarged or reduced, i.e., these drawings are not drawn to actual scale.

[0174] (3) Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0175] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. The scope of protection of this disclosure should be determined by the scope of protection of the claims.

Claims

1. An ionization source control device, comprising: An electrode structure, the electrode structure including a cavity, wherein the cavity includes an ion generation region and a reaction region; An ion generator configured to generate ions in the ion generation region; A voltage controller is configured to apply a positive voltage or a negative voltage to the electrode structure, and to switch the positive voltage and the negative voltage to control the ions; The injection tube is configured to allow the analyte flowing into the injection tube to undergo a chemical ionization reaction with the controlled ions in the reaction zone.

2. The ionization source control device according to claim 1, wherein, The electrode structure includes a first electrode group, which includes a first electrode structure and a second electrode structure arranged sequentially and insulated in a first direction, and the cavity extends in the first direction.

3. The ionization source control device according to claim 2, wherein, The cavity also includes a transition region between the ion generation region and the reaction region; The injection tube extends from outside the cavity in the first direction to the junction of the transition zone and the reaction zone.

4. The ionization source control device according to claim 3, wherein, The voltage controller includes a first DC power supply, a time relay and a switch connected in sequence, and a second DC power supply connected to the time relay; The first DC power supply is configured to simultaneously provide a positive voltage or simultaneously provide a negative voltage to the first electrode structure and the second electrode structure; The second DC power supply is configured to provide a pulse voltage signal to the time relay to control the time relay to turn on and off; The time relay is configured to control the switching of the connection contacts of the first and second terminals of the switch by opening and closing it, so as to achieve the switching of simultaneously applying a positive voltage to the first electrode structure and simultaneously applying a negative voltage to the second electrode structure.

5. The ionization source control device according to claim 4, wherein, The injection tube is conductive, and the time relay is configured to control the first terminal of the switch to be connected to the first electrode structure and the second electrode structure, and the second terminal to be connected to the injection tube; or, The time relay is configured to control the first terminal of the switch to be connected to the sample injection tube, and the second terminal to be connected to the first electrode structure and the second electrode structure.

6. The ionization source control device according to claim 4 or 5, wherein, The difference between the positive voltages simultaneously applied to the first electrode structure and the second electrode structure is greater than or equal to a first threshold; the difference between the negative voltages simultaneously applied to the first electrode structure and the second electrode structure is greater than or equal to a second threshold.

7. The ionization source control device according to claim 6, wherein, The positive voltage applied to the first electrode structure is +125V, and the positive voltage applied to the second electrode structure is +110V; or The negative voltage applied to the first electrode structure is -125V, and the negative voltage applied to the second electrode structure is -110V.

8. The ionization source control device according to claim 3, wherein, The first electrode structure includes a first hollow structure and a second hollow structure sleeved in the first hollow structure, with a portion of the sample inlet tube located in the second hollow structure.

9. The ionization source control device according to claim 8, wherein, The end of the injection tube located within the cavity is closer to the reaction zone than the end of the second empty cylinder structure that is closer to the reaction zone.

10. The ionization source control device according to claim 9, wherein, The distance between the end of the injection tube located inside the cavity and the end of the second empty cylinder structure near the reaction zone is 2mm to 8mm.

11. The ionization source control device according to claim 9 or 10, wherein, The second electrode structure includes a third hollow cylinder structure, the inner diameter of which is equal to the inner diameter of the first hollow cylinder structure.

12. The ionization source control device according to claim 4, wherein, The electrode structure further includes a second electrode group. The first electrode group and the second electrode group are arranged sequentially and insulated from each other in the first direction. The second electrode group includes a third electrode structure and a fourth electrode structure arranged sequentially and insulated from each other in the first direction.

13. The ionization source control device according to claim 12, wherein, The first electrode structure includes a first hollow cylinder structure and a second hollow cylinder structure sleeved in the first hollow cylinder structure. The second electrode structure includes a third hollow cylinder structure, the third electrode structure includes a fourth hollow cylinder structure, and the fourth electrode structure includes a fifth hollow cylinder structure. The inner diameters of the first hollow cylinder structure, the third hollow cylinder structure, the fourth hollow cylinder structure, and the fifth hollow cylinder structure are equal.

14. The ionization source control device according to claim 13, wherein, A portion of the injection tube is in the second empty cylinder structure, the end of the injection tube located within the cavity is closer to the reaction zone than the end of the second empty cylinder structure that is closer to the reaction zone, and the end of the injection tube located within the cavity is in the third empty cylinder structure.

15. The ionization source control device according to any one of claims 12 to 14, wherein, The first DC power supply is configured to simultaneously provide a positive voltage or simultaneously provide a negative voltage to at least two of the first electrode structure, the second electrode structure, the third electrode structure, and the fourth electrode structure. The second DC power supply is configured to provide a pulse voltage signal to the time relay to control the time relay to turn on and off; The time relay is configured to control the switching of the connection contacts of the first and second terminals of the switch by opening and closing it, so as to achieve the switching of simultaneously applying a positive voltage and simultaneously applying a negative voltage to at least two of the first electrode structure, the second electrode structure, the third electrode structure and the fourth electrode structure.

16. The ionization source control device according to claim 15, wherein, A gradually decreasing positive voltage or a gradually decreasing negative voltage is simultaneously applied to the first electrode structure, the second electrode structure, the third electrode structure, and the fourth electrode structure, and the difference between the positive voltages simultaneously applied to any two adjacent electrode structures is greater than or equal to a third threshold; the difference between the negative voltages simultaneously applied to any two adjacent electrode structures is greater than or equal to a fourth threshold.

17. The ionization source control device according to any one of claims 1 to 5, wherein, The electrode structure is made of at least one of conductive metals, carbon-based conductive materials, metal oxides, and ceramics.

18. The ionization source control device according to any one of claims 1 to 5, further comprising a reaction gas supply component, wherein, The reaction gas supply component includes a protective gas supply unit, a first gas supply unit, a second gas supply unit, and a zero-air supply unit connected in sequence. The protective gas supply unit is configured to provide protective gas, the first gas supply unit is configured to provide gas for forming the negative ions, the second gas supply unit is configured to provide gas for forming the positive ions, and the zero-air supply unit is configured to provide purified air.

19. The ionization source control device according to claim 18 further includes a rectifier screen, wherein, The rectifier screen is positioned between the reaction gas supply port corresponding to the reaction gas supply component and the ion generator.

20. A mass spectrometer detection system, comprising: The ionization source control device according to any one of claims 1 to 19 and the mass spectrometer connected to the ionization source control device.

21. The mass spectrometer detection system according to claim 20, wherein, The mass spectrometer includes a mass sampling cone and an orbital trap mass spectrometer detector, wherein the axis of the mass sampling cone in the first direction coincides with the axis of the sample inlet tube in the first direction.

22. The mass spectrometer detection system according to claim 21, wherein, The mass spectrometer sampling cone draws in the synthesized ions generated in the reaction zone through negative pressure aspiration and transmits them to the orbital trap mass spectrometer detector. The orbital trap mass spectrometer detector switches between positive mode detection and negative mode detection synchronously according to the time of positive and negative synthesized ions generated in the reaction zone.

23. The mass spectrometer detection system according to claim 22, wherein, The flow rate of the negative pressure aspiration gas at the mass spectrometer sampling cone is 1.2 L / min ~ 2.2 L / min.

24. The mass spectrometer detection system according to claim 22, wherein, The switching frequency between the positive mode detection and the negative mode detection set in the orbital trap mass spectrometer detector is consistent with the switching frequency between the positive voltage and the negative voltage set in the voltage controller.

25. The mass spectrometer detection system according to claim 24, wherein, The switching frequency between the positive mode detection and the negative mode detection of the orbital trap mass spectrometer is 1.2 Hz to 2.1 Hz, and the switching time between the positive voltage and the negative voltage set by the time relay is less than or equal to 0.1 s.

26. A method for controlling an ionization source, comprising: Ions are formed in the ion generation region, wherein the ion generation region is the ion generation region in the cavity included in the electrode structure; A positive voltage or a negative voltage is applied to the electrode structure, and the positive voltage and the negative voltage are switched to control the ions; The analyte flowing in through the injection tube undergoes a chemical ionization reaction with the controlled ions in the reaction zone, wherein the reaction zone is the reaction zone within the cavity included in the electrode structure.

27. The ionization source control method according to claim 26, wherein, The formation of ions in the ion generation region includes: simultaneously forming positive ions and negative ions, wherein the simultaneous formation of positive ions and negative ions includes: A positive ion reactant gas and a negative ion reactant gas are provided. The mixture of the positive ion reactant gas and the negative ion reactant gas is introduced into the ion generation zone. Under the action of the ion generator included in the ion source control device on the mixture of the positive ion reactant gas and the negative ion reactant gas, the positive ions and the negative ions are formed in the ion generation zone.

28. The ionization source control method according to claim 27, wherein, The positive ion reaction gas is nitric acid vapor, the negative ion reaction gas is diethylamine vapor, the positive ion is diethylamine cation, and the negative ion is nitrate ion.

29. The ionization source control method according to claim 27 or 28, wherein, The provision of positive ion reactant gas and negative ion reactant gas includes: Nitrogen gas, concentrated nitric acid liquid, diethylamine liquid, and zero air are supplied sequentially, and nitric acid vapor and diethylamine vapor are formed through liquid evaporation. The nitrogen gas, carrying the nitric acid vapor and the diethylamine vapor, is mixed and diluted with the zero air before entering the ion generation region.

30. The ionization source control method according to any one of claims 26 to 29, wherein, The electrode structure includes a first electrode group, which includes a first electrode structure and a second electrode structure arranged sequentially and insulated in a first direction, and the cavity extends in the first direction; Applying a positive voltage or a negative voltage to the electrode structure, and switching the positive voltage and the negative voltage to control the ions, includes: applying a first positive voltage and a second positive voltage to the first electrode structure and the second electrode structure respectively during a first time period to select the positive ions; In the second time period, a first negative voltage and a second negative voltage are applied to the first electrode structure and the second electrode structure, respectively, to select the negative ions, so as to achieve switching between the positive ions and the negative ions in adjacent first and second time periods.

31. The ionization source control method according to claim 30, wherein, The ionization source control device includes a voltage controller, which comprises a first DC power supply, a time relay, and a switch connected in sequence, and a second DC power supply connected to the time relay. The switching between the positive ions and the negative ions includes: The first DC power supply simultaneously provides a positive voltage or simultaneously provides a negative voltage to the first electrode structure and the second electrode structure; The second DC power supply provides a pulse voltage signal to the time relay to control the time relay to open and close. The time relay controls the switching of the connection contacts of the first and second terminals of the switch by opening and closing it, so as to switch between simultaneously applying a positive voltage and simultaneously applying a negative voltage to the first electrode structure and the second electrode structure.

32. The ionization source control method according to claim 31, wherein, The sample inlet tube is conductive. The time relay controls the first terminal of the switch to be connected to the first electrode structure and the second electrode structure, and the second terminal to be connected to the sample injection tube; or, The time relay controls the first end of the switch to be connected to the sample injection tube, and the second end to be connected to the first electrode structure and the second electrode structure.

33. A mass spectrometer detection method, comprising: An ionization source control device according to any one of claims 1 to 19 and a mass spectrometer connected to the ionization source control device are provided. The mass spectrometer includes a mass sampling cone and an orbital trap mass spectrometer detector. The mass sampling cone draws in ions generated in the reaction zone through negative pressure aspiration and transmits them to the orbital trap mass spectrometer detector. The orbital trap mass spectrometer detector switches between positive mode detection and negative mode detection synchronously according to the time of positive and negative reaction ions generated in the reaction zone.

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