A sampling device for rapid detection of volatile substances based on ion mobility spectrometry

Abstract

The present invention discloses a sampling device for rapid detection of volatile substances based on ion mobility spectrometry, comprising: a chamber fixing frame, a sampling mechanism and a heating transmission mechanism, wherein the chamber fixing frame is composed of 4 stainless steel cylinders, which are used to support and fix the sampling mechanism, and the sampling mechanism is used to carry the sample to be tested, and it can be displaced within a preset range so that it keeps contact or separation with the heating transmission mechanism, and the heating transmission mechanism is used to cooperate with the sampling mechanism to heat the gaseous sample to be tested. The present invention adopts a design combining hot carrier gas penetration purge with thermal analysis, which greatly reduces the possible loss of volatile substances in the sampling process on the one hand, and greatly shortens the time for all samples to be analyzed from the matrix on the other hand, while ensuring the sample injection amount, realizes the rapid detection of the volatile sample to be tested, can meet the needs of on-site real-time monitoring, and expands the scope of application of ion mobility spectrometry as a quantitative instrument, with a broader application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of ion mobility spectrometry detection equipment, and in particular to a sampling device for rapidly detecting volatile substances based on ion mobility spectrometry. Background Art

[0002] Ion mobility spectrometry is a technology that separates and detects gas-phase ions based on their different movement rates in an applied electric field under atmospheric pressure. It has the advantages of fast detection speed, high sensitivity, and low price. It is a real-time dynamic detection technology with great application prospects. The injector is an essential component of ion mobility spectrometry, and its performance directly determines the injection efficiency and the overall performance of ion mobility spectrometry. The products disclosed in "A halogen lamp injector for thermal analysis injection" with application numbers 201210563261.5 and "A gradient thermal analysis injector" with application numbers 201721139511.7 are the most commonly used thermal analysis injections before ionizing gaseous samples with atmospheric pressure ionization sources in the prior art. It integrates sampling and concentration, and has the advantages of fast speed, simple structure, and high efficiency. This is because gaseous sample molecules have higher ionization efficiency than the solvation effect in solid and liquid states where the intermolecular effects are extremely large, and are suitable for various atmospheric pressure ionization sources currently under development. However, the above-mentioned injector is suitable for the detection and analysis of samples with moderate volatility or even low volatility. For extremely volatile samples, due to the sealing and gas port design, part of the sample may not enter the ion mobility spectrometer during the injection process, thereby affecting the detection sensitivity and quantitative accuracy of volatile substances.

[0003] Therefore, it is of great practical value to develop a sampling device based on ion mobility spectrometry for rapid detection and accurate quantification of volatile substances such as sevoflurane. Summary of the invention

[0004] According to the technical problems raised above, the purpose of the present invention is to provide a sampling device for rapidly detecting volatile substances based on ion mobility spectrometry in view of the limitations of the existing methods.

[0005] The technical means adopted by the present invention are as follows:

[0006] A sampling device for rapid detection of volatile substances based on ion mobility spectrometry, comprising a sampling mechanism and a heating transmission mechanism;

[0007] The sample introduction mechanism comprises a sealed sample introduction chamber, a sample loading tray with a handle and a sealing strip; an opening is provided on one side of the sealed sample introduction chamber, and the sample loading tray with a handle enters the sealed sample introduction chamber from the opening; the sample loading tray with a handle is a flat plate structure with a through hole in the middle;

[0008] The sample tray with a handle is used to carry the sample to be tested, and it can be displaced within a preset range so that it can keep in contact with or separate from the heating transmission mechanism; the sealing strip is used to seal the contact between the sample tray with a handle and the sealed injection chamber to ensure the sealing of the sealed injection chamber;

[0009] The heating transmission mechanism is used to cooperate with the sample injection mechanism to transmit and heat the gaseous sample to be tested, including an upper polytetrafluoroethylene tube and a lower polytetrafluoroethylene tube respectively inserted into the upper and lower sides of the sealed sample injection chamber, and a heating sleeve arranged outside the upper polytetrafluoroethylene tube; the heating sleeve is preferably arranged in the middle section of the upper polytetrafluoroethylene tube;

[0010] The lower end of the upper polytetrafluoroethylene tube and the upper end of the lower polytetrafluoroethylene tube are respectively inserted into the upper and lower sides of the sealed injection chamber, and are coaxial with the center of the sample loading area of ​​the sample loading tray with a handle in the vertical direction; the other end of the upper polytetrafluoroethylene tube is connected to the ion migration tube, and an O-ring seal is provided at the connection; the other end of the lower polytetrafluoroethylene tube is used to pass pre-heated clean air as hot carrier gas, and the hot carrier gas carries the gaseous sample to be tested into the heating transmission mechanism through the through hole in the middle of the sample loading tray with a handle.

[0011] Furthermore, the sampling device also includes a chamber fixing frame; the sealed sampling chamber is fixed above the chamber fixing frame; preferably, the chamber fixing frame is composed of four stainless steel cylinders.

[0012] Furthermore, a groove matching the size of the sample tray with a handle is provided inside the sealed injection chamber, and circular through holes with the same diameter and coaxial in the vertical direction are opened in the centers of the upper and lower planes for the insertion of the polytetrafluoroethylene tube. The diameter of the circular through hole is 2 to 8 mm; the sample tray with a handle can enter the sealed injection chamber through the sealing strip, and the position of the sample tray with a handle is determined by the groove of the sealed injection chamber.

[0013] Furthermore, the through hole of the sample tray with a handle is circular with a diameter of 10 to 30 mm; in the through hole, on the same horizontal plane, a number of corrosion-resistant, insulating and heat-conductive narrow thin sheets are embedded at equal intervals in two directions perpendicular to each other. On the one hand, the thin sheets allow hot carrier gas to pass through, and on the other hand, they play a role in carrying and heating samples. The width of the thin sheets is 0.5 to 2 mm, the length is 3 to 30 mm, the thickness is 0.1 to 1 mm, and the distance between adjacent thin sheets is 0.05 to 2 mm.

[0014] Furthermore, the sample tray with handle is made of corrosion-resistant, insulating and heat-conductive materials;

[0015] If the sample tray with handle is a circular flat plate, the annular portion outside the central circular through hole has a diameter of 15 to 40 mm and a thickness of 1 to 8 mm, which can perfectly match the groove embedded in the sealed sample injection chamber to achieve the function of positioning the sample tray.

[0016] Furthermore, the sample tray with a handle can be moved in a specific direction, and the acquisition and injection of the sample to be tested can be achieved through push-pull operations.

[0017] Furthermore, the sealed injection chamber can be embedded with a heating rod and a sensor for use with samples with low volatility or when heating is required to increase the analysis speed. The heating temperature range is 40 to 200°C. Its inner wall is a heat-conducting material such as stainless steel or aluminum, and its outer wall is a heat-insulating material such as polytetrafluoroethylene or Peek material.

[0018] Furthermore, the heating sleeve is a hollow cylindrical structure, which can be embedded with a heating rod and a sensor, and is used for samples with poor volatility or when heating is required to increase the analysis speed. The heating temperature range is 40 to 200°C.

[0019] Furthermore, the interfaces where the polyfluoro tube involved in the sample injection device directly contacts the sample injection mechanism and the ion transfer tube are sealed with corrosion-resistant, insulating and heat-resistant O-rings to ensure the sealing of the sample injection device.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] 1. The present invention provides a sampling device for rapidly detecting volatile substances in ion mobility spectrometry, which expands the application scope of ion mobility spectrometry as a quantitative instrument and has broader application prospects.

[0022] 2. In the sealed injection chamber adopted by the present invention, the hot carrier gas penetration purge is combined with thermal analysis, which, on the one hand, greatly reduces the possible loss of volatile substances in the injection process, and on the other hand, greatly shortens the time for all samples to be analyzed from the matrix. While ensuring the sample injection amount, it realizes rapid detection of the sample to be tested, which can meet the needs of on-site real-time monitoring and broaden the applicable scenarios of ion mobility spectrometry. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] 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.

[0024] Figure 1 It is the sample injection device of the present invention.

[0025] Figure 2 This is a schematic diagram of a sample tray with a handle.

[0026] In the figure, (1) chamber fixing frame, (2) lower polytetrafluoroethylene tube, (3) sealed sample injection chamber, (4) sample loading tray with handle, (5) sealing strip, (6) upper polytetrafluoroethylene tube, and (7) heating sleeve. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below with reference to the accompanying drawings.

[0028] like Figure 1 As shown, the present application provides a sampling device for rapid detection of volatile substances based on ion mobility spectrometry, including a chamber fixing frame, a sampling mechanism and a heating transmission mechanism; the chamber fixing frame is composed of 4 stainless steel cylinders, the sampling mechanism includes a sealed sampling chamber, a sample tray with a handle and a sealing strip, and the heating transmission mechanism includes an upper polytetrafluoroethylene tube, a lower polytetrafluoroethylene tube and a heating sleeve;

[0029] The lower end of the upper polytetrafluoro tube and the upper end of the lower polytetrafluoro tube are respectively inserted into the upper and lower sides of the sealed injection chamber, and are coaxial with the center of the sample loading area of ​​the sample loading tray with a handle in the vertical direction; the other end of the upper polytetrafluoro tube is connected to the ion migration tube; the other end of the lower polytetrafluoro tube is introduced with pre-heated clean air as hot carrier gas.

[0030] A groove matching the size of the sample tray with a handle is provided inside the sealed injection chamber to determine the position of the sample tray with a handle; circular through holes with the same diameter and coaxial in the vertical direction are opened in the centers of the upper and lower planes of the sealed injection chamber for the insertion of the polytetrafluoroethylene tube, and the diameter of the circular through hole is 4mm.

[0031] The sample tray with handle is a circular flat plate structure with a circular through hole in the middle. The diameter of the circular through hole is 15mm. In the circular through hole, a number of corrosion-resistant, insulating and heat-conductive narrow thin sheets are embedded at equal intervals on the same horizontal plane and in two directions perpendicular to each other. The width of the thin sheets is 1mm, the length is 3 to 15mm, the thickness is 0.2mm, and the distance between adjacent thin sheets is 0.5mm.

[0032] The sample tray with handle is made of corrosion-resistant, insulating and heat-conductive materials; the inner wall of the sealed sample injection chamber is made of stainless steel heat-conductive material, and the outer wall is made of polytetrafluoroethylene insulation material.

[0033] Optionally, a heating rod and a sensor are embedded in the sealed injection chamber, and the heating temperature is 100°C.

[0034] The heating sleeve is a hollow cylindrical structure with a built-in heating rod and sensor, and the heating temperature is 100°C.

[0035] The interfaces where the polyfluoro tube involved in the injection device directly contacts the injection mechanism and the ion transfer tube are sealed with corrosion-resistant, insulating and heat-resistant O-rings to ensure the sealing of the entire injection device.

[0036] During sample injection, the upper end of the upper polytetrafluoroethylene tube is connected to the ion transfer tube, and the connection is sealed with an O-ring; then the sample to be tested is dripped into the center of the sample loading area of ​​the sample loading tray with a handle, the sample loading tray with a handle is passed through the sealing strip and pushed into the sealed injection chamber, and the sealed injection chamber is sealed with a sealing strip to ensure the sealing of the sealed injection chamber; the hot carrier gas carries the sample molecules to be tested through the lower polytetrafluoroethylene tube, the sealed injection chamber and the upper polytetrafluoroethylene tube to ensure that the sample to be tested is in a gaseous state, and then enters the ion transfer tube to realize sample separation and detection.

[0037] 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 sampling device for rapid detection of volatile substances based on ion mobility spectrometry, characterized in that: It includes a sample injection mechanism and a heating transmission mechanism; The sample injection mechanism comprises a sealed sample injection chamber, a sample loading tray with a handle and a sealing strip; an opening is provided on one side of the sealed sample injection chamber, and the sample loading tray with a handle enters the sealed sample injection chamber from the opening, and the opening is sealed with a sealing strip; the sample loading tray with a handle is a flat plate structure with a through hole in the middle; The heating transmission mechanism includes an upper polytetrafluoro tube, a lower polytetrafluoro tube and a heating sleeve; the upper polytetrafluoro tube and the lower polytetrafluoro tube are respectively inserted into the upper and lower sides of the sealed injection chamber; the heating sleeve is sleeved on the outer side of the upper polytetrafluoro tube; the positions where the upper polytetrafluoro tube and the lower polytetrafluoro tube are inserted into the sealed injection chamber are coaxial in the vertical direction with the center of the sample loading area of ​​the sample loading tray with a handle.

2. The sampling device for rapid detection of volatile substances based on ion mobility spectrometry according to claim 1, characterized in that: The sample injection device also includes a chamber fixing frame; the sealed sample injection chamber is fixed above the chamber fixing frame; preferably, the chamber fixing frame is composed of four stainless steel cylinders.

3. The sampling device for rapid detection of volatile substances based on ion mobility spectrometry according to claim 1, characterized in that: The sealed injection chamber has a groove inside that matches the size of the sample tray with a handle, and the position of the sample tray with a handle is determined by the groove of the sealed injection chamber; the centers of the upper and lower planes of the sealed injection chamber are both provided with circular through holes with the same diameter and coaxial in the vertical direction for the insertion of the polyfluoro tube, and the diameter of the circular through hole is 2 to 8 mm.

4. The sampling device for rapid detection of volatile substances based on ion mobility spectrometry according to claim 1, characterized in that: The through hole of the sample tray with a handle is circular, with a diameter of 10 to 30 mm; a plurality of thin sheets are embedded in the through hole, with a width of 0.5 to 2 mm, a length of 3 to 30 mm, a thickness of 0.1 to 1 mm, and a spacing of 0.05 to 2 mm between adjacent thin sheets; the thin sheets are arranged at equal intervals in two directions perpendicular to each other on the same horizontal plane; the thin sheets are corrosion-resistant, insulating and heat-conductive.

5. The sampling device for rapid detection of volatile substances based on ion mobility spectrometry according to claim 1, characterized in that: The sample tray with a handle is made of corrosion-resistant, insulating and heat-conductive material.

6. The sampling device for rapid detection of volatile substances based on ion mobility spectrometry according to claim 1, characterized in that: The sealed injection chamber is provided with a heating rod and a sensor, and the heating temperature is 40-200° C. The inner wall of the sealed injection chamber is made of heat-conducting material, and the outer wall is made of heat-insulating material.

7. The sampling device for rapid detection of volatile substances based on ion mobility spectrometry according to claim 6, characterized in that: The heat-conducting material is stainless steel or aluminum; the heat-insulating material is polytetrafluoroethylene or Peek material.

8. The sampling device for rapid detection of volatile substances based on ion mobility spectrometry according to claim 1, characterized in that: The heating sleeve is embedded with a heating rod and a sensor, and the heating temperature is 40-200°C.

9. The sampling device for rapid detection of volatile substances based on ion mobility spectrometry according to claim 1, characterized in that: The interfaces between the upper polytetrafluoroethylene tube, the lower polytetrafluoroethylene tube and the sealed injection cavity are sealed with corrosion-resistant, insulating and heat-resistant O-rings.

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