Connecting device for chromatographic column and ion migration tube of GC-IMS analyzer

Abstract

The invention provides a GC-IMS analyzer chromatographic column and ion migration tube connecting device, and relates to the technical field of instrument analysis, the GC-IMS analyzer chromatographic column and ion migration tube connecting device comprises a gas chromatograph, an ion migration tube, a connecting device, an adjusting three-way valve and a dopant bottle; the gas chromatography is communicated with the ion migration tube through a connecting device; the dopant bottle is communicated with the connecting device through the adjusting three-way valve, and SPI ionization or CI ionization is achieved. According to the connecting device for the chromatographic column and the ion migration tube of the GC-IMS analyzer, the capillary chromatographic column is vertically connected with the ion migration tube, so that switching or adjustment of multiple functions such as sampling efficiency, an ionization mode and a one-way and two-way airflow mode can be realized; the sample injection efficiency can be adjusted by adjusting the insertion depth of the capillary chromatographic column; under the action of adjusting the three-way valve, when the migration tube is ionized, whether a dopant exists or not can be realized, and the change of a photo ionization mode is realized; the position of the air outlet of the ion migration tube is changed through the adjusting bolt, and switching of unidirectional and bidirectional airflow modes of the ion migration tube is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of instrument analysis, and in particular to a GC-IMS analyzer chromatographic column and ion migration tube connecting device, in particular to a GC-IMS analyzer interface connecting device with a VUV lamp as a migration tube ionization source. Background Art

[0002] Ion mobility spectrometry (IMS) is a separation and detection technology based on the difference in the migration rate of ions in a gas damping environment driven by an electric field. In IMS, the unidirectional airflow mode and the bidirectional airflow mode are two different gas flow directions, which have a significant impact on the detection sensitivity and separation efficiency. In the unidirectional airflow mode, the airflow direction is single, and the airflow flows continuously in one direction from the sample inlet to the ion detector. The advantages of the unidirectional airflow mode are simple structure and easy operation, but there may be certain limitations in sensitivity and resolution. In the bidirectional airflow mode, the airflow direction in the ionization zone is opposite to that in the drift zone, which helps to more effectively remove the by-products and excess neutral molecules produced during the ionization process, thereby improving the detection sensitivity and resolution.

[0003] Photoionization source (PI) as a non-radioactive ionization source has been widely used in ion mobility spectrometry. Photoionization is divided into direct photoionization (SPI) and chemical ionization (CI). Direct photoionization is a special soft ionization technology with a simple ionization method. Any atom or molecule with ionization energy lower than the photon energy will be directly ionized under the irradiation of vacuum ultraviolet lamp. It has a wide linear dynamic range and is suitable for the analysis of samples of different concentrations. The mass spectrum obtained is relatively simple, mainly composed of molecular ion peaks, which is suitable for rapid analysis and direct, online monitoring of VOCs; chemical ionization has the characteristics of few fragment ions, large ionization cross section and high sensitivity. At the same time, chemical ionization can ionize sample molecules with ionization energy higher than the photon energy, expanding the range of detectable compounds, covering more than 200 VOCs / SVOCs such as aldehydes, ketones, alcohols, lipids, ethers, phenols, amines, alkanes, alkenes, alkynes, aromatic hydrocarbons, halogenated hydrocarbons, and organic sulfides.

[0004] Gas chromatography-ion mobility spectrometry (GC-IMS) is an analytical technique that combines gas chromatography (GC) and ion mobility spectrometry (IMS). It has the characteristics of high sensitivity, rapid analysis and real-time detection, and is mainly used in environmental monitoring, food flavor analysis and medical fields. This technology is based on the separation and detection of volatile organic compounds (VOCs) in the gas phase. The gas chromatography part separates the compounds in the mixture one by one through the chromatographic column, while the ion mobility spectrometry part converts the compounds into ions through ionization and analyzes the compounds using the difference in the migration speed of ions in the electric field.

[0005] There are currently some published patents for GC-IMS coupling interfaces. Patent CN202311714070.9 connects the chromatographic column vertically to the ion migration tube through an interface to achieve switching between barrel-shaped and sheet-shaped ionization sources, but the chromatographic effluent is seriously affected by the floating gas and has low sensitivity; Patents CN202121343049.9 and CN202110669990.8 disclose the interface connection between the needle-shaped injection cannula and the ion mobility spectrometer. The connection between the capillary and the injection cannula in this structure has a non-zero dead volume, which will cause chromatographic deformation; Patent CN202222372181.3 The sample gas flowing out of the chromatographic column first passes through the sample gas passage to enter the coupling interface and then enters the ion source, and the gas in the sample gas passage will dilute the sample gas, thereby reducing the detection sensitivity; Patent CN201920282908.4 The interface adopts a Z-shaped flow path, and the light source is irradiated to the gas flow. Although the contact time between the light source and the sample is prolonged, the chromatographic resolution will be seriously reduced, and the separated substances will be mixed again in the Z-shaped gas path. Patent CN201310741366.X discloses that the chromatographic effluent is split into two migration tube reaction zones, which will reduce the detection sensitivity; Patent CN202111589494.8 uses a solenoid valve switching interface to realize single- and dual-mode switching injection of GC-IMS and MS. The interface part has a large dead volume, which will affect the peak shape.

[0006] This patent designs a GC-IMS analyzer combined interface device, which can realize zero dead volume GC efficient injection, VUV lamp ionization source ion transfer tube ionization mode switching, different migration tubes in the single and two-way gas flow switching and other functions. Summary of the invention

[0007] According to the above technical problems that the existing GC-IMS coupling interface has low sensitivity and large dead volume in the interface part, a GC-IMS analyzer chromatographic column and ion transfer tube connection device is provided. The present invention mainly vertically connects the capillary chromatographic column with the ion transfer tube, and can realize the switching or adjustment of multiple functions such as injection efficiency, ionization mode and unidirectional and bidirectional airflow mode.

[0008] The technical means adopted by the present invention are as follows:

[0009] A GC-IMS analyzer chromatographic column and ion migration tube connecting device comprises: a gas chromatograph, an ion migration tube, a connecting device, an adjusting three-way valve and a dopant bottle; the gas chromatograph is connected with the ion migration tube through the connecting device, and the capillary chromatographic column in the gas chromatograph is heated in a chromatographic column oven, and analytes are gradually separated; the dopant bottle is connected with the connecting device through the adjusting three-way valve, and the dopant in the dopant bottle is emptied or passes through the connecting device and enters the ion migration tube together with the outflow in the capillary chromatographic column under the action of a reagent carrier gas through the adjusting three-way valve, so as to realize SPI ionization or CI ionization.

[0010] Furthermore, the gas chromatograph comprises a chromatographic column oven and a capillary chromatographic column, wherein the capillary inlet end of the capillary chromatographic column is arranged in the chromatographic column oven, and the capillary outlet end of the capillary chromatographic column is inserted into the ion migration tube.

[0011] Furthermore, the ion transfer tube is a migration time ion transfer tube of a VUV lamp ionization source, and three air vents are arranged between the ionization source and the ion gate of the ion transfer tube. The three air vents are located on the same side, namely, the left air outlet of the transfer tube, the middle air inlet of the transfer tube, and the right air outlet of the transfer tube.

[0012] Furthermore, the connecting device includes a chromatographic column interface and an adjusting plug; the chromatographic column interface is a hollow T-shaped structure, and a left interface air vent and a right interface air vent are respectively provided on the left and right sides of the hollow T-shaped structure; a mixing cavity is provided at the upper end of the hollow T-shaped structure, and the adjusting plug horizontally penetrates the mixing cavity; an interface middle air vent is provided in the center of the hollow T-shaped structure, and the interface middle air vent is communicated with the ion migration tube and the mixing cavity.

[0013] Furthermore, three vents are provided on the adjusting bolt, namely the left vent of the adjusting bolt, the middle vent of the adjusting bolt and the right vent of the adjusting bolt; at the same time, the left vent of the adjusting bolt and the right vent of the adjusting bolt are staggered and connected with the left vent and the right vent of the interface; the middle vent of the adjusting bolt is connected with the hollow T-shaped structure.

[0014] Furthermore, an air inlet is provided at the lower part of the chromatographic column interface, the air inlet is connected to one port of the regulating three-way valve, another port opposite to the air inlet connection port is connected to the dopant bottle, and the third port of the regulating three-way valve is emptied.

[0015] Furthermore, the chromatographic column interface of the connecting device is vertically connected to the ion migration tube, the three vents of the chromatographic column interface are sequentially connected to the vents on the same side of the ion migration tube, and the capillary chromatographic column is inserted into the ion migration tube through the middle vent of the chromatographic column interface.

[0016] Furthermore, the gas chromatograph also includes an MCC column and a preparative column.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] The present invention provides a GC-IMS analyzer chromatographic column and ion migration tube connecting device, which can realize the switching or adjustment of multiple functions such as injection efficiency, ionization mode and unidirectional and bidirectional airflow modes by vertically connecting the capillary chromatographic column and the ion migration tube; the injection efficiency can be adjusted by adjusting the insertion depth of the capillary chromatographic column; under the action of adjusting the three-way valve, when the migration tube is ionized, it can be realized whether there is a dopant, thereby realizing the change of the photoionization mode; and the unidirectional and bidirectional airflow modes of the ion migration tube can be switched by changing the position of the ion migration tube outlet by using the adjusting bolt.

[0019] The GC-IMS analyzer chromatographic column and ion migration tube connecting device can also realize the combined optimization of multiple adjustment functions. The device has the advantages of simple operation and convenient function switching, and is suitable for application on the GC-IMS analyzer. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 This is a schematic diagram of the structure of a GC-IMS analyzer ion migration tube operating in unidirectional gas flow and SPI ionization mode.

[0022] Figure 2 The schematic diagram is a structural diagram of an ion migration tube of a GC-IMS analyzer operating in unidirectional gas flow and CI ionization mode.

[0023] Figure 3 The schematic diagram shows the structure of a GC-IMS analyzer ion migration tube operating in bidirectional gas flow and SPI ionization mode.

[0024] Figure 4 The schematic diagram is a structural diagram of a GC-IMS analyzer ion migration tube operating in bidirectional gas flow and CI ionization mode.

[0025] In the figure: 1. chromatographic column oven; 2. chromatographic column interface; 3. capillary chromatographic column; 4. mixing chamber; 5. middle air vent of interface; 6. right air vent of interface; 7. adjusting plug; 8. right air vent of adjusting plug; 9. ion migration tube; 10. ion gate; 11. right air outlet of migration tube; 12. capillary outlet; 13. middle air inlet of migration tube; 14. VUV lamp; 15. left air outlet of migration tube; 16. left air vent of adjusting plug; 17. left air vent of interface; 18. middle air vent of adjusting plug; 19. adjusting three-way valve; 20. dopant bottle. DETAILED DESCRIPTION

[0026] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0029] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, the numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0030] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0031] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0032] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0033] like Figure 1-4As shown, the present invention provides a GC-IMS analyzer chromatographic column and ion migration tube connecting device, including: a gas chromatograph, an ion migration tube, a connecting device, an adjusting three-way valve and a dopant bottle.

[0034] The gas chromatograph comprises a chromatographic column oven 1 and a capillary chromatographic column 3, wherein the capillary chromatographic column 3 is heated by the chromatographic column oven 1, one end of which is connected to a carrier gas and the other end of which is inserted into a connecting device; an ion migration tube 9 is a migration time ion migration tube of an ionization source of a VUV lamp 14, and three vents on the same side are arranged between the ionization source and an ion gate 10, namely, a right gas outlet 11 of the migration tube is located near the ion gate 10, a middle sample inlet 13 of the migration tube is located in a reaction zone and a left gas outlet 15 of the migration tube is located in an ionization zone near the ionization source.

[0035] The connecting device includes a chromatographic column interface 2 and an adjusting bolt 7. The chromatographic column interface 2 is a hollow T-shaped structure, and a vent is provided on each of the two walls of the T-shaped structure, namely, a left vent 17 of the interface and a right vent 6 of the interface. A mixing chamber 4 is provided at the upper end of the T-shaped structure, and the mixing chamber 4 is connected from left to right, and the T-shaped adjusting bolt 7 runs through it. The adjusting bolt 7 has three vents, namely, a left vent 16 of the adjusting bolt, a right vent 8 of the adjusting bolt, and a middle vent 18 of the adjusting bolt. The left and right vents of the adjusting bolt are connected to the left and right vents of the chromatographic column interface in a staggered manner, that is, when the left vent 16 of the adjusting bolt is connected to the left vent 17 of the interface, the right vent 8 of the adjusting bolt is not connected to the right vent 6 of the interface, and vice versa. However, the middle vent 18 of the adjusting bolt can always be connected to the middle vent 5 of the chromatographic column interface. There is an air inlet at the lower end of the chromatographic column interface 2 connected to one port of the regulating three-way valve 19, the opposite port of the regulating three-way valve 19 is connected to the doping agent bottle 20, and the third port of the regulating three-way valve 19 is emptied.

[0036] The connection device chromatographic column interface 2 is vertically connected to the ion transfer tube 9, and the three ports of the chromatographic column interface 2 are sequentially connected to the vents on the same side of the ion transfer tube 9. The capillary chromatographic column 3 can be inserted into the reaction zone of the transfer tube through the middle vent 5 of the chromatographic column interface.

[0037] The capillary chromatographic column 3 in the chromatographic column oven 1 is in a heated state, and the analyte is gradually separated under the action of the carrier gas. By adjusting the position of the capillary outlet 12, different injection efficiencies can be changed. Under the action of the reagent carrier gas, the dopant can be emptied or passed through the chromatographic column interface 2 and enter the ion migration tube 9 together with the outflow of the capillary chromatographic column 3 under the action of the regulating three-way valve 19. When there is no dopant, SPI ionization is achieved, and when there is a dopant, CI ionization is achieved. When the left vent 16 of the regulating plug is connected to the left vent 17 of the interface, the airflow of the ion migration tube 9 is unidirectional. If the right vent 8 of the regulating plug is connected to the right vent 6 of the interface, the airflow of the ion migration tube 9 is bidirectional, thereby realizing bidirectional airflow switching.

[0038] The connecting device is in a heat preservation state to reduce sample residue;

[0039] The regulating three-way valve can be electric or manual;

[0040] Gas phase capillaries, including capillary columns, MCC columns and preparative columns.

[0041] Example 1

[0042] like Figure 1 As shown, this embodiment provides a schematic structural diagram of a GC-IMS analyzer chromatographic column and ion transfer tube connection device, and the ionization source VUV lamp 14 and the ion transfer tube 9 are coaxially placed.

[0043] When the ionization energy of the sample molecule is lower than the photon energy, the three-way valve 19 is adjusted to empty, and the direct photoionization (SPI) mode is adopted. The position of the adjustment plug 7 is shown in the figure, and the left vent hole 16 of the adjustment plug is connected with the left vent hole 17 of the interface. At this time, it is a one-way airflow mode, and the sensitivity can be optimized by changing the position of the capillary outlet 12. The sample flowing out of the capillary outlet 12 flows toward the ionization source VUV lamp 14 under the purge of the floating gas, and flows out from the left vent hole 17 of the interface to complete the detection.

[0044] Example 2

[0045] like Figure 2 As shown, this embodiment provides a schematic structural diagram of a GC-IMS analyzer chromatographic column and ion transfer tube connection device, and the ionization source VUV lamp 14 and the ion transfer tube 9 are coaxially placed.

[0046] When the ionization energy of the sample molecules is higher than the photon energy, the three-way valve 19 is adjusted to allow the dopant to pass through the chromatographic column interface 2 and enter the mixing chamber 4 together with the outflow of the capillary chromatographic column 3. The ionization mode is changed to chemical ionization (CI). The position of the adjusting plug 7 is shown in the figure. The left air hole 16 of the adjusting plug is connected to the left air vent 17 of the interface. At this time, it is a unidirectional airflow mode. The sample gas and the dopant are mixed in the mixing chamber 4 and then enter the ion migration tube 9. The sample gas and the dopant mixture flows inside the ion migration tube 9 under the purge of the floating gas and flows out from the left air vent 17 of the interface to complete the detection.

[0047] Example 3

[0048] like Figure 3 As shown, this embodiment provides a schematic structural diagram of a GC-IMS analyzer chromatographic column and ion transfer tube connection device, and the ionization source VUV lamp 14 and the ion transfer tube 9 are coaxially placed.

[0049] When the ionization energy of the sample molecule is lower than the photon energy, the three-way valve 19 is adjusted to empty, and the direct photoionization (SPI) mode is adopted. The position of the adjustment plug 7 is shown in the figure, and the right vent hole 8 of the adjustment plug is connected with the right vent port 6 of the interface. At this time, it is a two-way airflow mode, and the sensitivity can be optimized by changing the position of the capillary outlet 12. The sample flowing out of the capillary outlet 12 flows out from the right vent port 6 of the interface to complete the detection.

[0050] Example 4

[0051] like Figure 4 As shown, this embodiment provides a schematic structural diagram of a GC-IMS analyzer chromatographic column and ion transfer tube connection device, and the ionization source VUV lamp 14 and the ion transfer tube 9 are coaxially placed.

[0052] When the ionization energy of the sample molecules is higher than the photon energy, the three-way valve 19 is adjusted to allow the dopant to pass through the chromatographic column interface 2 and enter the mixing chamber 4 together with the outflow of the capillary chromatographic column 3. The ionization mode is changed to chemical ionization (CI). The position of the adjusting plug 7 is shown in the figure. The right vent 8 of the adjusting plug is connected to the right vent 6 of the interface. At this time, it is a two-way airflow mode. The sample gas and the dopant are mixed in the mixing chamber 4 and then enter the ion migration tube 9, and finally flow out from the right vent 6 of the interface to complete the detection.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A GC-IMS analyzer chromatographic column and ion transfer tube connection device, characterized in that: include: A gas chromatograph, an ion transfer tube (9), a connecting device, an adjusting three-way valve (19), and a dopant bottle (20); the gas chromatograph is connected to the ion transfer tube (9) through the connecting device, and when a capillary chromatographic column (3) in the gas chromatograph is heated in a chromatographic column oven (1), analytes are gradually separated; the dopant bottle (20) is connected to the connecting device through the adjusting three-way valve (19), and under the action of a reagent carrier gas, the dopant in the dopant bottle (20) is emptied or passes through the connecting device and enters the ion transfer tube (9) together with the outflow from the capillary chromatographic column (3), thereby realizing SPI ionization or CI ionization.

2. The GC-IMS analyzer chromatographic column and ion migration tube connecting device according to claim 1, characterized in that: The gas chromatograph comprises a chromatographic column oven (1) and a capillary chromatographic column (3), wherein the capillary inlet end of the capillary chromatographic column (3) is arranged in the chromatographic column oven (1), and the capillary outlet end (12) of the capillary chromatographic column (3) is inserted into the ion migration tube (9).

3. The GC-IMS analyzer chromatographic column and ion migration tube connecting device according to claim 1, characterized in that: The ion transfer tube (9) is a migration time ion transfer tube (9) of a VUV lamp (14) ionization source. Three vents are arranged between the ionization source and the ion gate (10) of the ion transfer tube (9). The three vents are located on the same side and are, in order, a left gas outlet (15) of the transfer tube, a middle gas inlet (13) of the transfer tube, and a right gas outlet (11) of the transfer tube.

4. The GC-IMS analyzer chromatographic column and ion transfer tube connecting device according to claim 1, characterized in that: The connecting device comprises a chromatographic column interface (2) and an adjusting bolt (7); the chromatographic column interface (2) is a hollow T-shaped structure, and a left interface vent (17) and a right interface vent (6) are respectively arranged on the left and right sides of the hollow T-shaped structure; a mixing chamber (4) is arranged at the upper end of the hollow T-shaped structure, and the adjusting bolt (7) horizontally penetrates the mixing chamber (4); an interface middle vent (5) is arranged at the center of the hollow T-shaped structure, and the interface middle vent (5) is communicated with the ion migration tube (9) and the mixing chamber (4).

5. The GC-IMS analyzer chromatographic column and ion transfer tube connecting device according to claim 4, characterized in that: The adjusting bolt (7) is provided with three ventilation holes, namely, the left ventilation hole (16) of the adjusting bolt, the middle ventilation hole (18) of the adjusting bolt and the right ventilation hole (8) of the adjusting bolt; at the same time, the left ventilation hole (16) of the adjusting bolt and the right ventilation hole (8) of the adjusting bolt are staggeredly connected with the left ventilation port (17) of the interface and the right ventilation port (6) of the interface; the middle ventilation hole (18) of the adjusting bolt is connected with the hollow T-shaped structure.

6. The GC-IMS analyzer chromatographic column and ion transfer tube connecting device according to claim 4, characterized in that: An air inlet is provided at the lower part of the chromatographic column interface (2), and the air inlet is connected to one port of the regulating three-way valve (19), and the other port opposite to the air inlet connection port is connected to the dopant bottle (20), and the third port of the regulating three-way valve (19) is emptied.

7. The GC-IMS analyzer chromatographic column and ion transfer tube connecting device according to claim 4, characterized in that: The chromatographic column interface (2) of the connecting device is vertically connected to the ion migration tube (9), the three vents of the chromatographic column interface (2) are sequentially connected to the vents on the same side of the ion migration tube (9), and the capillary chromatographic column (3) passes through the middle vent of the chromatographic column interface (2) and is inserted into the ion migration tube (9).

8. The GC-IMS analyzer chromatographic column and ion transfer tube connecting device according to claim 2, characterized in that: The gas chromatograph further comprises an MCC column and a preparative column.

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