Flame ionization device and mass spectrometry method

Abstract

The application relates to a flame ionization device and a mass spectrometry method, which comprises a combustion chamber, an ionization assembly, an electrode and a fairing, the combustion chamber is provided with an opening and an ionization outlet, the ionization outlet is communicated with an inlet of a mass spectrometer, the ionization assembly comprises an ionization flame, the ionization flame can be combusted in the combustion chamber, the ionization flame can generate plasma, the electrode is installed in the combustion chamber and is oppositely arranged with the ionization outlet, the fairing is oppositely arranged with the opening, so that a plasma area is formed between the ionization flame and the fairing, and the plasma area ionizes and gasifies a sample to be detected. The combustion chamber and the fairing are arranged, so that the ionization flame is prevented from being affected by the environment, and a high-density plasma area is formed; the electrode is oppositely arranged with the ionization outlet, so that the plasma area is in an electric field generated by the electrode, positive and negative charge particles in the plasma move in opposite directions, neutralization is prevented, the quantity of the plasma is improved, the ionization efficiency is improved, the detection signal is more stable, and the detection result repeatability is improved.

Description

Technical Field

[0001] This invention relates to the field of tooling and fixture technology, and more particularly to a flame ionization device. Background Technology

[0002] In in-situ ionization-based mass spectrometry analysis methods, the sample to be analyzed does not need to undergo chromatographic separation and can be directly used for mass spectrometry analysis. It has the characteristics of in-situ, instantaneous, online, rapid and high-throughput, which greatly expands the application range of mass spectrometry.

[0003] In mass spectrometry, the in-situ ion source plays a crucial role in the processing and ionization of the sample. In-situ ion sources based on flame plasma ionization generate high-temperature plasma, which vaporizes and ionizes the sample before it enters the mass spectrometer for detection. However, in existing flame ionization techniques, the in-situ flame ion source is open and lacks a charge separation device. The positive and negative charges in the plasma neutralize upon cooling, leading to unstable flame gas flow, reduced plasma quantity and utilization, decreased ionization efficiency, and poor repeatability of the detection results.

[0004] Therefore, there is an urgent need for a flame ionization device to solve the above-mentioned technical problems. Summary of the Invention

[0005] One objective of this invention is to provide a flame ionization device to solve the problems of unstable flame flow, reduced plasma quantity, and reduced ionization efficiency caused by the open nature of existing in-situ flame ion sources and the lack of charge separation devices.

[0006] To achieve the above objectives, the present invention provides a flame ionization device.

[0007] A flame ionization device, comprising:

[0008] A combustion chamber having an opening and an ionization outlet configured to communicate with the inlet of a mass spectrometer;

[0009] An ionization assembly includes an ionization flame, the ionization flame being capable of combustion within a combustion chamber, and the ionization flame being capable of generating plasma;

[0010] An electrode is installed in the combustion chamber and is positioned opposite to the ionization outlet;

[0011] A shroud, disposed opposite to the opening, forms a plasma zone between the ionizing flame and the shroud, the plasma zone being configured to ionize and vaporize the sample to be tested.

[0012] Furthermore, the ionization outlet is elongated, and the length direction of the ionization outlet is parallel to the height direction of the combustion chamber.

[0013] Furthermore, the length of the ionization outlet is 1.5cm-3.5cm and the width is 0.7cm-1cm.

[0014] Furthermore, the distance between the ionization outlet and the inlet is 0.1cm-6cm.

[0015] Furthermore, the distance from the fairing to the opening is 2cm-5cm.

[0016] Furthermore, the flame ionization device also includes a sampling device capable of storing a sample to be tested. The sampling device can extend into the combustion chamber from the gap between the shroud and the opening and is positioned above the ionized flame.

[0017] Furthermore, the ionization assembly also includes a fuel pipe that extends into the combustion chamber, and the fuel flowing through the fuel pipe is ignited to form the ionized flame.

[0018] Furthermore, the combustion chamber is provided with a flame inlet, through which the fuel pipe can extend into the combustion chamber.

[0019] Furthermore, the combustion chamber is also provided with an air inlet, and multiple air inlets are arranged at intervals along the circumference of the flame inlet.

[0020] Another objective of this invention is to propose a mass spectrometry analysis method to solve the problems of unstable flame flow, reduced plasma quantity, and reduced ionization efficiency caused by the open nature and lack of charge separation devices in existing flame in-situ ion sources.

[0021] A mass spectrometry analysis method includes the following steps:

[0022] Turn on the mass spectrometer and scan the mass spectrometry signal;

[0023] The flame ionization device using any of the above schemes ionizes and vaporizes the sample to be tested: voltage is applied to the electrodes, fuel is delivered into the combustion chamber and ignited to obtain an ionized flame that generates plasma, and a plasma zone is formed between the ionized flame and the shroud. After the fuel is ignited for a preset time, the sample to be tested is placed in the plasma zone, and the flame ionization device is moved to make the mass spectrometry signal the strongest.

[0024] Record the scan data to obtain the mass spectrum of the sample to be tested.

[0025] The beneficial effects of this invention are as follows:

[0026] The flame ionization device provided by the present invention includes a combustion chamber, an ionization component, an electrode, and a shroud. The combustion chamber has an opening and an ionization outlet. The ionization outlet is configured to communicate with the inlet of a mass spectrometer. The ionization component includes an ionization flame. The ionization flame can burn in the combustion chamber and generate plasma. The electrode is installed in the combustion chamber and is arranged opposite to the ionization outlet. The shroud is arranged opposite to the opening to form a plasma region between the ionization flame and the shroud. The plasma region is configured to ionize and vaporize the sample to be tested. The design of the combustion chamber and shroud protects the ionizing flame from environmental influences, resulting in a more stable detection signal and improved repeatability. The combustion chamber walls effectively block thermal radiation, reducing heat loss and increasing the temperature of the ionizing flame. The shroud prevents plasma from escaping upwards, creating a high-density plasma zone, increasing plasma quantity and utilization, and thus improving ionization efficiency. The electrodes and ionization outlet are positioned opposite each other, placing the plasma zone within the electric field generated by the electrodes. Positive and negative charged particles in the plasma move in opposite directions, retaining useful charged particles for ionizing the sample while removing interfering particles. This increases the amount of plasma available for sample ionization, reduces interference from oppositely charged particles, and allows more sample ions to reach the mass spectrometer inlet for easier detection, thereby improving ionization efficiency. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the flame ionization device provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of charge separation in the plasma region of the flame ionization device provided in an embodiment of the present invention;

[0029] Figure 3 This is a comparison diagram of the total ion chromatograms of flame ionization mass spectrometry of air components obtained using the mass spectrometry analysis method provided in this embodiment and the conventional mass spectrometry analysis method, respectively;

[0030] Figure 4 This is a flame ionization mass spectrum of metronidazole obtained using the mass spectrometry analysis method provided in the embodiments of the present invention;

[0031] Figure 5 This is a flame ionization mass spectrum of metronidazole obtained using traditional mass spectrometry analysis methods;

[0032] Figure 6 This is a flame ionization mass spectrum of ornidazole obtained using the mass spectrometry analysis method provided in the embodiments of the present invention;

[0033] Figure 7 This is the flame ionization mass spectrum of ornidazole obtained using traditional mass spectrometry analysis methods;

[0034] Figure 8 The mass spectrum of the flame ionization of cypermethrin was obtained using the mass spectrometry analysis method provided in the embodiments of the present invention.

[0035] Figure 9 The mass spectrum of the flame ionization of cypermethrin was obtained using traditional mass spectrometry analysis methods.

[0036] Figure 10 This is a flame ionization mass spectrum of betaine obtained using the mass spectrometry analysis method provided in the embodiments of the present invention;

[0037] Figure 11 The flame ionization mass spectrum of betaine was obtained using traditional mass spectrometry analysis methods.

[0038] In the picture:

[0039] 100 - Flame ionization device; 200 - Mass spectrometer; 201 - Inlet;

[0040] 1-Combustion chamber; 2-Ionization assembly; 3-Electrode; 4-Fairing; 5-Plasma zone; 6-Sampling device;

[0041] 11-Opening; 12-Ionization outlet; 13-Air inlet; 14-Flame inlet; 21-Ionization flame; 22-Fuel pipe. Specific Implementation

[0042] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present invention are shown in the accompanying drawings, not all of them.

[0043] This invention defines certain directional terms. Unless otherwise stated, the directional terms used, such as "up," "down," "left," "right," "inner," and "outer," are used for ease of understanding and therefore do not constitute a limitation on the scope of protection of this invention.

[0044] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0045] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0046] This embodiment provides a flame ionization device 100 as an in-situ ion source to ionize and vaporize the sample to be tested. It is used in conjunction with a mass spectrometer 200 to perform mass spectrometry analysis on the sample, eliminating the need for chromatographic separation and improving the efficiency of mass spectrometry analysis. This flame ionization device 100 is suitable for solid, liquid, or gaseous samples, as well as highly polar or low-polarity samples, and is also applicable to organometallic compounds, demonstrating a wide range of applications.

[0047] like Figures 1-2As shown, the flame ionization device 100 includes a combustion chamber 1, an ionization component 2, an electrode 3, and a shroud 4. The combustion chamber 1 has an opening 11 and an ionization outlet 12. The ionization outlet 12 is configured to communicate with the inlet 201 of the mass spectrometer 200. The ionization component 2 includes an ionization flame 21. The ionization flame 21 can burn in the combustion chamber 1 and generate plasma. The electrode 3 is installed in the combustion chamber 1 and is arranged opposite to the ionization outlet 12. The shroud 4 is arranged opposite to the opening 11 to form a plasma region 5 between the ionization flame 21 and the shroud 4. The plasma region 5 is configured to ionize and vaporize the sample to be tested. The arrangement of combustion chamber 1 and shroud 4 protects the ionizing flame 21 from environmental influences, making it more stable and resulting in a more stable detection signal and improved repeatability of detection results. Furthermore, the walls of combustion chamber 1 effectively block heat radiation, reducing heat loss and thus increasing the temperature of the ionizing flame 21. This reduces the impact of temperature on the plasma (as the temperature of plasma region 5 decreases, the plasma reforms into neutral, uncharged matter). Shroud 4 prevents plasma from escaping upwards, forming a high-density plasma region 5, increasing the quantity and utilization of plasma, thereby improving ionization efficiency. Electrode 3 is positioned opposite to ionization outlet 12, ensuring that plasma region 5 is located within electrode 3. Between the plasma region 5 and the ionization outlet 12, the plasma region 5 is in the electric field generated by the electrode 3. Positive and negative charged particles in the plasma move in opposite directions. Useful charged particles for ionizing the sample are retained, while anti-charged particles that interfere with sample ionization are attracted and removed by the electrode 3. This prevents the charged particles in the plasma from being neutralized, which helps to increase the amount of plasma used for ionizing the sample. It also reduces the interference of anti-charged particles (which can attract ions from the sample) on the ions of the sample. Furthermore, it allows more sample ions to reach the inlet 201 of the mass spectrometer 200 smoothly, facilitating detection and thus improving ionization efficiency.

[0048] Furthermore, the inlet 201 of the mass spectrometer 200 is a capillary tube, and the ionization outlet 12 is connected to the inlet 201, so that the ionized sample ions to be tested can be sent into the mass spectrometer 200 for mass spectrometry analysis.

[0049] Furthermore, the ionization outlet 12 is elongated, with its length parallel to the height of the combustion chamber 1. In other words, the ionization outlet 12 is a narrow, elongated slit, facilitating the adjustment of the combustion chamber 1's position along its height. This ensures that the generated ions of the sample are closest to the inlet 201 of the mass spectrometer 200, allowing more sample ions to reach the inlet 201 smoothly for detection, thereby improving ionization efficiency.

[0050] Specifically, the ionization outlet 12 has a length of 1.5cm-3.5cm and a width of 0.7cm-1cm.

[0051] Specifically, the distance between the ionization outlet 12 and the inlet 201 is 0.1cm-6cm.

[0052] Furthermore, the inner diameter of the combustion chamber 1 is 2.4cm-4cm, and the height is 3.5cm-6cm. These dimensions facilitate combustion of the ionized flame 21 and protect it from environmental influences. However, the dimensions are not limited to these specifications; any size that facilitates combustion and operation is acceptable.

[0053] Furthermore, electrode 3 is installed on the inner wall of combustion chamber 1 and is positioned opposite to ionization outlet 12, with plasma zone 5 located between electrode 3 and ionization outlet 12. This arrangement allows plasma zone 5 to be situated within the electric field generated by electrode 3, causing positive and negative charged particles in the plasma to move in opposite directions. Useful charged particles for ionizing the sample are retained, while anti-charged particles that interfere with sample ionization are attracted and removed by electrode 3, achieving charge separation and preventing neutralization of charged particles in the plasma. This increases the amount of plasma available for ionizing the sample and reduces interference from anti-charged particles (which attract ions). It also allows more sample ions to reach the inlet 201 of mass spectrometer 200 smoothly for detection, thereby improving ionization efficiency.

[0054] Furthermore, electrode 3 can be a square plate or a needle-tip electrode. In this embodiment, the shape and size of electrode 3 are not limited, as long as it can generate an electric field and act on the ions of the sample to be tested and the plasma generated by the ionization flame 21.

[0055] Furthermore, electrode 3 can be made of a high-temperature resistant conductive material. Specifically, tungsten copper can be selected as the high-temperature resistant conductive material.

[0056] Furthermore, the top of the combustion chamber 1 is open, that is, the top of the combustion chamber 1 is provided with the above-mentioned opening 11, and the above-mentioned shroud 4 is provided above the opening 11. There is a gap between the opening 11 and the shroud 4 to facilitate the combustion of the ionized flame 21 and to facilitate the insertion of the sample to be tested into the combustion chamber 1.

[0057] Furthermore, the distance between the fairing 4 and the opening 11 is 2cm-5cm. This arrangement serves several purposes: first, it ensures smooth airflow within the combustion chamber 1, facilitating the combustion of the ionizing flame 21; second, it allows the sample to be inserted into the combustion chamber 1 through the gap between the opening 11 and the fairing 4, enabling the sample to be vaporized and ionized; and third, it prevents the rapid loss of plasma quantity and heat, forming a high-density plasma zone 5 between the ionizing flame 21 and the fairing 4.

[0058] In this embodiment, the specific value of the distance from the fairing 4 to the opening 11 is not limited. It can be set according to the actual situation or experience, as long as it facilitates the combustion of the ionizing flame 21, the formation of the plasma zone 5, and the delivery of the sample to be tested into the combustion chamber 1.

[0059] Specifically, the fairing 4 can be a circular or nearly circular cover, with the opening of the fairing 4 facing the opening 11. Of course, it is not limited to the above shape, and this embodiment does not limit it. It can be set according to the actual situation, as long as it can prevent the plasma from escaping upward and form a high-density plasma region 5.

[0060] Furthermore, the inner diameter of the fairing 4 is 2cm-5cm. Of course, it is not limited to the above dimensions and can be set according to the actual situation, as long as it can prevent the plasma from escaping upwards and form a high-density plasma region 5.

[0061] Furthermore, the flame ionization device 100 also includes a sampling device 6, which can store the sample to be tested. The sampling device 6 can extend into the combustion chamber 1 through the gap between the shroud 4 and the opening 11 and is positioned above the ionization flame 21. The plasma generated by the ionization flame 21 can ionize and vaporize the sample to be tested, so that mass spectrometry analysis can be performed smoothly.

[0062] Furthermore, the sampling device 6 can be a glass rod, clamps, tweezers, glass capillary tube, etc., which can dip into, clamp, and aspirate the sample to be tested. This embodiment does not limit the specific structure of the sampling device 6. The appropriate sampling device 6 can be selected according to the morphological characteristics of the sample to be tested. For example, a glass rod can dip into liquid samples, a glass capillary tube can aspirate powdered solid or liquid samples, and clamps and tweezers can clamp solid samples.

[0063] Regarding the sampling amount of the sample to be tested by the sampling device 6, this embodiment does not limit this, as the sampling amount of the sample to be tested has little impact on the results of mass spectrometry analysis. However, in order to improve the sensitivity of mass spectrometry analysis, the concentration of the liquid sample to be tested can be appropriately increased.

[0064] Furthermore, the ionization assembly 2 also includes a fuel pipe 22, which can extend into the combustion chamber 1, and the fuel flowing in the fuel pipe 22 is ignited to form an ionized flame 21.

[0065] Furthermore, a flame inlet 14 is provided on the combustion chamber 1, through which the fuel pipe 22 can extend into the combustion chamber 1.

[0066] Specifically, the flame inlet 14 is located at the bottom of the combustion chamber 1, which saves more space and is easier to operate than opening the flame inlet 14 on the side wall of the combustion chamber 1.

[0067] Furthermore, the flame inlet 14 is located at the center of the bottom of the combustion chamber 1.

[0068] Furthermore, an air inlet 13 is provided on the combustion chamber 1, and multiple air inlets 13 are arranged at intervals along the circumference of the flame inlet 14.

[0069] Specifically, the multiple air inlets 13 are all the same size and are evenly arranged circumferentially along the flame inlet 14. This arrangement ensures uniform and stable air intake, thereby ensuring that the ionizing flame 21 is stably positioned in the center of the combustion chamber 1. Air from outside the combustion chamber 1 enters the combustion chamber 1 through the air inlets 13 and flows out through the gap between the opening 11 and the shroud 4, forming a smooth airflow within the combustion chamber 1, thus ensuring complete combustion of the ionizing flame 21. After the ionizing flame 21 is ignited for 1-2 minutes, i.e., after the temperature inside the combustion chamber 1 rises, the air inside the combustion chamber 1 is heated, the airflow rises faster, and the ionizing flame 21 burns more completely, thereby generating a larger quantity of plasma.

[0070] Fuel is delivered into combustion chamber 1 through fuel pipe 22 and ignited at the tail end of fuel pipe 22 to form ionizing flame 21. A high-density plasma region 5 is formed between ionizing flame 21 and shroud 4. Sampling device 6 extends into plasma region 5 through the gap between opening 11 and shroud 4. The sample to be tested is vaporized and ionized. The sample ions pass through ionization outlet 12 and inlet 201 and enter mass spectrometer 200 for mass spectrometry analysis. Sampling device 6 places the sample to be tested in plasma region 5. The oppositely charged particles in plasma region 5 are attracted and removed by electrode 3, allowing the useful particles in plasma region 5 to transfer charge to the sample to be tested without interference. The sample to be tested is simultaneously vaporized and ionized to form sample ions, which then pass through ionization outlet 12 and inlet 201 and enter mass spectrometer 200 for mass spectrometry analysis.

[0071] Furthermore, both the combustion chamber 1 and the fairing 4 can be made of high-temperature resistant materials. Specifically, ceramics can be selected as the high-temperature resistant material.

[0072] The flame ionization device 100 provided in this embodiment, compared to igniting fuel in a confined space, heating the sample to be tested (such as a spray sample), and controlling the temperature within the confined space, offers several advantages. While the plasma does not dissipate within the confined space, the large sample volume of the spray sample leads to significant heat loss through evaporation, causing temperature unevenness within the confined space. Plasma is highly sensitive to temperature; at low temperatures, the positive and negative charges in the plasma recombine, reducing the plasma quantity. Furthermore, the confined space may result in incomplete fuel combustion; the spray sample itself is a gas flow, which can cause instability in the ionization flame flow, leading to unstable mass spectrometry signals.

[0073] This embodiment also provides a mass spectrometry analysis method, including the following steps:

[0074] Turn on the mass spectrometer 200 and scan the mass spectrometry signal;

[0075] The above-mentioned flame ionization device 100 is used to ionize and vaporize the sample to be tested: the electrode 3 is pressurized, the fuel is delivered into the combustion chamber 1 and ignited to obtain an ionization flame 21 that generates plasma, and a plasma region 5 is formed between the ionization flame 21 and the rectifier 4. After the fuel is ignited for a preset time, the sample to be tested is placed in the plasma region 5, and the flame ionization device 100 is moved to make the mass spectrometry signal the strongest.

[0076] Record the scan data to obtain the mass spectrum of the sample to be tested.

[0077] Furthermore, such as Figure 2 As shown, the steps of applying pressure to electrode 3 include: applying voltage to electrode 3 using a high-voltage power supply, with the other end of the high-voltage power supply grounded to form a circuit, generate current, and thus generate an electric field.

[0078] Furthermore, fuel is delivered into combustion chamber 1 via fuel pipe 22.

[0079] Furthermore, the preset time for igniting the fuel is 1-2 minutes.

[0080] Furthermore, a long-handled lighter can be used to ignite the fuel.

[0081] Furthermore, the sample to be tested is placed in the plasma region 5 using the sampling device 6.

[0082] Further, the manufacturing steps of combustion chamber 1 and shroud 4 are as follows: ceramic clay is made by adding water to ceramic clay, and combustion chamber 1 and shroud 4 are made of ceramic clay. Combustion chamber 1 is a cylinder with a bottom and an opening 11 at the top. Flame inlet 14 and air inlet 13 are opened at the bottom, and ionization outlet 12 is opened on the side wall. Shroud 4 is made into a cover with a certain arc shape. Then, combustion chamber 1 and shroud 4 are placed in a muffle furnace and fired for 5 hours at a temperature of 900°C. After cooling, they are taken out, and electrodes 3 are installed on the inner wall of combustion chamber 1.

[0083] To verify the detection sensitivity of this mass spectrometry method, a comparison with traditional mass spectrometry methods can be made. In this embodiment, the samples selected for testing were air, metronidazole, ornidazole, propoxur, and betaine. Traditional mass spectrometry methods refer to the use of conventional flame ionization devices to ionize and vaporize the samples. Conventional flame ionization devices are open-type and lack charge separation devices.

[0084] like Figure 3As shown, the left half is the total ion chromatogram of air components obtained by the traditional mass spectrometry analysis method, and the right half is the total ion chromatogram of air components obtained by the mass spectrometry analysis method provided in this embodiment. The signal intensity of the left half is approximately 60,000, while the signal intensity of the right half is approximately 170,000. It can be seen that the detection sensitivity of the mass spectrometry analysis method provided in this embodiment is significantly greater than that of the traditional mass spectrometry analysis method.

[0085] In addition, the signal strength in the left half decreased significantly over time, which was caused by the deflection of the ionized flame 21 due to the ambient airflow. Meanwhile, the signal strength in the right half fluctuated up and down over time, without any obvious unilateral movement upward or downward. This indicates that the ionized flame 21 was not affected by the ambient airflow.

[0086] like Figure 4 As shown, this is the flame ionization mass spectrum of metronidazole obtained by the mass spectrometry analysis method provided in this embodiment. Figure 5 As shown, the flame ionization mass spectrum of metronidazole obtained by the traditional mass spectrometry analysis method is approximately m / z 172. However, the mass spectrometry analysis method provided in this embodiment detects a signal intensity that is approximately 10 times that of the traditional mass spectrometry analysis method, which is about an order of magnitude higher.

[0087] like Figure 6 As shown, this is the flame ionization mass spectrum of ornidazole obtained by the mass spectrometry analysis method provided in this embodiment. Figure 7 As shown, the flame ionization mass spectrum of ornidazole obtained by the traditional mass spectrometry analysis method is approximately m / z 220. However, the mass spectrometry analysis method provided in this embodiment detects a signal intensity that is approximately 10 times that of the traditional mass spectrometry analysis method, which is about an order of magnitude higher.

[0088] Both metronidazole and ornidazole are in tablet form, which can be directly picked up and placed in plasma zone 5 for ionization and vaporization.

[0089] like Figure 8 As shown, this is the flame ionization mass spectrum of cypermethrin obtained by the mass spectrometry analysis method provided in this embodiment. Figure 9 As shown, the flame ionization mass spectra of propargite obtained by conventional mass spectrometry analysis methods are both detected. The mass spectrometry signal of propargite hydrogen ions is approximately m / z 210, the mass spectrometry signal of propargite ammonia ions is approximately m / z 227, and the mass spectrometry signal of propargite potassium ions is approximately m / z 248. However, the signal intensity detected by the mass spectrometry analysis method provided in this embodiment is approximately 10 times that of the signal intensity detected by conventional mass spectrometry analysis methods, which is about an order of magnitude higher.

[0090] like Figure 10 As shown, this is the flame ionization mass spectrum of betaine obtained by the mass spectrometry analysis method provided in this embodiment. Figure 11 As shown, the flame ionization mass spectrum of betaine obtained by the traditional mass spectrometry analysis method is approximately m / z 339 for potassium-added betaine and approximately m / z 639 for potassium-added betaine dimer. However, the signal intensity detected by the mass spectrometry analysis method provided in this embodiment is approximately 10 times that of the traditional mass spectrometry analysis method, which is about an order of magnitude higher.

[0091] Both cypermethrin and betaine were dissolved in methanol, then absorbed by sampling device 6 and placed in plasma zone 5 for ionization and vaporization.

[0092] In summary, after comparing several groups of test samples with different configurations, the detection sensitivity of the mass spectrometry analysis method provided in this embodiment is significantly improved.

[0093] Although the present invention has been described in detail above with general descriptions, specific embodiments, and experiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A flame ionization device, characterized by, The application relates to a flame ionization device (100) comprising: a combustion chamber (1) having an opening (11) and an ionization outlet (12) configured to communicate with an inlet (201) of a mass spectrometer (200); an ionization assembly (2) comprising an ionization flame (21) capable of burning in the combustion chamber (1) and capable of generating plasma; a fairing (4) disposed opposite the opening (11) and having a distance of 2-5 cm to the opening (11) to form a plasma zone (5) between the ionization flame (21) and the fairing (4), the plasma zone (5) being configured to ionize and vaporize a sample to be tested; an electrode (3) mounted in the combustion chamber (1) and disposed opposite the ionization outlet (12), and the plasma zone (5) is located between the electrode (3) and the ionization outlet (12) so that the plasma zone (5) is in an electric field generated by the electrode (3), the positive and negative charge particles in the plasma move in opposite directions, the useful charged particles in the plasma for ionizing the sample to be tested are retained, and the opposite charge particles in the plasma that interfere with the ionization of the sample are attracted and removed by the electrode (3); a sampling device (6) capable of storing the sample to be tested, the sampling device (6) being capable of extending into the combustion chamber (1) from a gap between the fairing (4) and the opening (11) and being disposed above the ionization flame (21).

2. The flame ionization device of claim 1, wherein, The ionization outlet (12) is in the shape of a long strip, and the length direction of the ionization outlet (12) is parallel to the height direction of the combustion chamber (1).

3. The flame ionization device of claim 2, wherein, The length of the ionization outlet (12) is 1.5-3.5 cm, and the width is 0.7-1 cm.

4. The flame ionization device of claim 1, wherein, The distance between the ionization outlet (12) and the inlet (201) is 0.1-6 cm.

5. The flame ionization device of claim 1, wherein, The ionization assembly (2) further comprises a fuel pipe (22) capable of extending into the combustion chamber (1), and the ionization flame (21) is ignited by fuel flowing in the fuel pipe (22).

6. The flame ionization device of claim 5, wherein, The combustion chamber (1) is provided with a flame inlet (14), and the fuel pipe (22) can extend into the combustion chamber (1) through the flame inlet (14).

7. The flame ionization device of claim 6, wherein, The combustion chamber (1) is further provided with an air inlet (13), and a plurality of air inlets (13) are arranged at intervals in the circumferential direction of the flame inlet (14).

8. A mass spectrometry method characterized by, The application further discloses a method for ionizing and vaporizing a sample to be tested by using the flame ionization device (100). The method comprises the following steps: turning on the mass spectrometer (200) and scanning a mass spectrum signal; using the flame ionization device (100) to ionize and vaporize the sample to be tested: applying voltage to the electrode (3), feeding fuel into the combustion chamber (1), igniting the ionization flame (21) to generate plasma, and forming a plasma zone (5) between the ionization flame (21) and the fairing (4); after the fuel is ignited for a preset time, the sample to be tested is placed in the plasma zone (5), and the flame ionization device (100) is moved to make the mass spectrum signal strongest. The scanning data is recorded to obtain a mass spectrum of the sample to be tested.

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