A spatially distributed dual ionization source device

Abstract

This invention relates to mass spectrometry analysis instruments, specifically a spatially distributed dual ionization source device. It includes a dual-aperture electrode, ionization source I, ionization source II, a vacuum chamber, a rectangular rod assembly, and a cylindrical rod assembly. One end of the vacuum chamber has the dual-aperture electrode, and the other end has an ion output port. The dual-aperture electrode has two circular through-holes. Ionization source I and ionization source II are respectively disposed at the outer ends of the two circular through-holes of the dual-aperture electrode. The rectangular rod assembly and the cylindrical rod assembly are sequentially spaced within the vacuum chamber along the ion transport direction. A DC voltage is applied to the dual-aperture electrode, the rectangular electrode rod assembly, and the cylindrical electrode rod assembly, decreasing sequentially. An radio frequency voltage is also applied to the rectangular electrode rod assembly and the cylindrical electrode rod assembly. This invention enables the combination of multiple different ionization sources, thereby ionizing samples under different ionization modes, significantly enhancing qualitative analysis capabilities and effectively broadening the application range.

Description

Technical Field

[0001] This invention relates to mass spectrometry analysis instruments, specifically a spatially distributed dual ionization source device. Background Technology

[0002] In the field of complex environment analysis, soft ionization technology has become a highly regarded analytical method due to its superior efficiency in producing high-molecular ions and its ease of spectral interpretation. However, the application scope of various soft ionization sources currently faces certain limitations. Specifically, photoionization technology using commercially available Kr lamps as the light source exhibits significantly limited ionization efficiency when processing substances with low photoionization cross-sections or requiring ionization energies exceeding 10.6 eV; while proton transfer ionization technology performs poorly with compounds whose proton affinity is lower than that of water molecules. More critically, in the crucial analytical step of isomer identification, soft ionization sources lack the ability to directly obtain structural information, posing a potential risk of misjudgment. In contrast, while electron impact ionization technology can provide fragment ion information, the increased complexity of spectral interpretation and decreased sensitivity when dealing with samples from complex environments severely restrict its wider application and promotion. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide a spatially distributed dual ionization source device to solve the problems of insufficient information acquisition and narrow application range of a single ionization source.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] The present invention provides a spatially distributed dual ionization source device, including a dual-aperture electrode, ionization source I, ionization source II, a vacuum cavity, a rectangular rod assembly and a cylindrical rod assembly, wherein a dual-aperture electrode is provided at one end of the vacuum cavity and an ion output port is provided at the other end;

[0006] The double-hole electrode has two circular through holes. Ionization source I and ionization source II are respectively disposed at the outer ends of the two circular through holes of the double-hole electrode. Rectangular rod groups and cylindrical rod groups are arranged alternately in the vacuum chamber along the ion transport direction.

[0007] DC voltages are applied to the dual-aperture electrode, the rectangular electrode rod group, and the cylindrical electrode rod group, decreasing sequentially. Radio frequency voltages are also applied to the rectangular electrode rod group and the cylindrical electrode rod group.

[0008] The dual-aperture electrode is a conical structure that protrudes outward, and the conical structure is coaxial with the ion output port.

[0009] The two circular through holes are symmetrical about the horizontal plane passing through the vertex of the double-aperture electrode, and the central axis of the two circular through holes is on the same plane as the vertex of the double-aperture electrode and the axial center line of the ion output port.

[0010] The thickness of the double-hole electrode is 2-4 mm; the diameter of the circular through hole is 1-2 mm.

[0011] Ionization source I and ionization source II are located along the central axis of the two circular through holes of the double-hole electrode, and are in contact with the outer surface of the double-hole electrode.

[0012] The rectangular rod group includes at least four rectangular electrode rods that are evenly distributed circumferentially and arranged parallel to the axis of the double-aperture electrode, and the number of rectangular electrode rods is even.

[0013] On the cross-section of the rectangular rod group, the centers of the plurality of rectangular electrode rods are located on the same circumference A; the wide face of each rectangular electrode rod is perpendicular to the line connecting the center of circumference A and the center point of the rectangular electrode rod on circumference A.

[0014] The cylindrical rod assembly includes at least four cylindrical electrode rods that are evenly distributed circumferentially and arranged parallel to the axis of the double-aperture electrode, and the number of cylindrical electrode rods is even.

[0015] On the cross-section of the cylindrical rod assembly, the centers of multiple cylindrical rod assemblies are located on the same circumference B, and the radius of circumference B is smaller than the radius of circumference A.

[0016] The rectangular electrode rods in the rectangular electrode rod group have the same dimensions: length 10-30mm, width 5-15mm, thickness 2-6mm, and radius of circumference A 10-20mm.

[0017] The cylindrical electrode rods in the cylindrical electrode rod group have the same dimensions: a length of 60-120 mm, a radius of 4-8 mm, and a radius of circumference B of 10-15 mm.

[0018] The electrodes in the dual-aperture electrode, rectangular electrode rod group, and cylindrical electrode rod group are made of conductive metal or have a conductive metal layer plated on their surface.

[0019] The DC voltage applied to the double-aperture electrode, the rectangular electrode rod group and the cylindrical electrode rod group decreases sequentially to form a DC gradient electric field, with a gradient voltage of 1-20V / cm.

[0020] The applied radio frequency peak-to-peak amplitudes are equal and the phases are opposite for every two adjacent rectangular electrode rods in the rectangular electrode rod group; the applied radio frequency peak-to-peak amplitudes are equal and the phases are opposite for every two adjacent cylindrical electrode rods in the cylindrical electrode rod group; the applied radio frequency is 0.5-5MHz, and the radio frequency peak-to-peak value is 10-500V.

[0021] The vacuum chamber is a horizontally placed rectangular cylindrical structure; a vacuum extraction port is provided on the lower side wall of the vacuum chamber near the ion output port, and a vacuum pump is connected to the extraction port to maintain the vacuum in the vacuum chamber. The gas pressure in the vacuum chamber is maintained between 0.1-2 Pa.

[0022] The advantages and beneficial effects of this invention are as follows: This invention provides a spatially distributed dual ionization source device, which achieves efficient focusing and transmission of ions over a wide range after ionization through the combination of a short quadrupole rectangular rod and a quadrupole cylindrical rod, thereby ensuring the sensitivity of the spatially distributed dual ionization sources. Furthermore, the gas pressures between the two spatially distributed ionization sources are independent, thus enabling the combination of various different ionization sources. This allows for the ionization of samples under different ionization modes, significantly enhancing qualitative capabilities and effectively broadening the application range. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a spatially distributed dual ionization source device according to the present invention;

[0024] Figure 2 The results of the transport efficiency of ions with m / z 100 after ionization source in the SIMION simulation of the embodiments of the present invention are shown.

[0025] In the diagram: 1-Double-hole electrode, 2-Ionization source I, 3-Ionization source II, 4-Vacuum cavity, 5-Rectangular rod assembly, 6-Cylindrical rod assembly, 7-Ion output port, 8-Vacuum extraction port. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] See Figure 1As shown, the present invention provides a spatially distributed dual ionization source device, including a dual-aperture electrode 1, an ionization source I 2, an ionization source II 3, a vacuum chamber 4, a rectangular rod group 5, and a cylindrical rod group 6. The vacuum chamber 4 has the dual-aperture electrode 1 at one end and an ion output port 7 at the other end. The dual-aperture electrode 1 has two circular through holes. The ionization source I 2 and ionization source II 3 are respectively disposed at the outer ends of the two circular through holes of the dual-aperture electrode 1. The rectangular rod group 5 and the cylindrical rod group 6 are sequentially spaced within the vacuum chamber 4 along the ion transport direction. A DC voltage is applied to the dual-aperture electrode 1, the rectangular electrode rod group 5, and the cylindrical electrode rod group 6, decreasing sequentially. A radio frequency voltage is also applied to the rectangular electrode rod group 5 and the cylindrical electrode rod group 6.

[0028] In an embodiment of the present invention, the vacuum chamber 4 is a horizontally placed rectangular cylindrical structure; a vacuum extraction port 8 is provided on the lower side wall of the vacuum chamber 4 near the ion output port 7, and a vacuum pump is connected to the extraction port 8 to maintain the vacuum inside the vacuum chamber 4. The gas pressure inside the vacuum chamber 4 is maintained between 0.1-2 Pa.

[0029] join Figure 1 As shown, in an embodiment of the present invention, the dual-aperture electrode 1 is a conical structure that protrudes outward, and the conical structure is coaxial with the ion output port 7; the cone apex of the dual-aperture electrode 1 faces left, the central axis of the two circular through holes is perpendicular to the outer wall surface of the dual-aperture electrode 1, the two circular through holes are symmetrical about the horizontal plane passing through the apex of the dual-aperture electrode 1, and the central axis of the two circular through holes is on the same plane as the apex of the dual-aperture electrode 1 and the axial center line of the ion output port 7.

[0030] Preferably, the thickness of the double-hole electrode 1 is 2-4 mm; the diameter of the circular through hole is 1-2 mm.

[0031] In embodiments of the present invention, ionization source I2 and ionization source II3 are respectively located along the central axis of the two circular through holes of the double-hole electrode 1 and are in contact with the outer surface of the double-hole electrode 1. Specifically, the gas pressures of ionization source I2 and ionization source II3 are independent of each other, and they can be photoionization sources, proton transfer ionization sources, electron bombardment ionization sources, etc.

[0032] join Figure 1 As shown, in an embodiment of the present invention, the rectangular rod group 5 includes at least four rectangular electrode rods evenly distributed circumferentially and arranged parallel to the axis of the double-aperture electrode 1, wherein the number of rectangular electrode rods is even. One end face of each rectangular electrode rod is located close to the double-aperture electrode 1 and is spaced apart from the double-aperture electrode 1, while the other end face of each rectangular electrode rod is located away from the double-aperture electrode 1.

[0033] Specifically, on the cross-section of the rectangular rod group 5, the centers of multiple rectangular electrode rods are located on the same circumference A; the wide face of each rectangular electrode rod is perpendicular to the line connecting the center of circumference A and the center point of the rectangular electrode rod on circumference A.

[0034] join Figure 1 As shown, in an embodiment of the present invention, the cylindrical rod assembly 6 includes at least four cylindrical electrode rods evenly distributed circumferentially and arranged parallel to the axis of the double-aperture electrode 1, the number of cylindrical electrode rods being even. On the cross-section of the cylindrical rod assembly 6, the centers of the multiple cylindrical rod assemblies 6 are located on the same circumference B, and the radius of circumference B is smaller than the radius of circumference A. One end face of each cylindrical electrode rod is opposite to and spaced from the other end face of a corresponding rectangular electrode rod, and the other end face of each cylindrical electrode rod is located on the side closest to the ion output port 7, and is spaced from the ion output port 7. Specifically, the plane containing circumference A and the plane containing circumference B are parallel to each other, and the vertex of the double-aperture electrode 1, the center of circumference A, the center of circumference B, and the axial centerline of the ion output port 7 are all collinear.

[0035] Preferably, the dimensions of each rectangular electrode rod in the rectangular electrode rod group 5 are consistent, with a length of 10-30mm, a width of 5-15mm, a thickness of 2-6mm, and a radius of circumference A of 10-20mm; the dimensions of each cylindrical electrode rod in the cylindrical electrode rod group 6 are consistent, with a length of 60-120mm, a radius of 4-8mm, and a radius of circumference B of 10-15mm; the electrodes in the double-hole electrode 1, the rectangular electrode rod group 5, and the cylindrical electrode rod group 6 are made of conductive metal or have a conductive metal layer plated on their surface.

[0036] In this embodiment, the DC voltage applied to the dual-aperture electrode 1, the rectangular electrode rod group 5, and the cylindrical electrode rod group 6 decreases sequentially to form a DC gradient electric field, with a gradient voltage of 1-20V / cm; the peak-to-peak amplitude of the radio frequency applied to each pair of adjacent rectangular electrode rods in the rectangular electrode rod group 5 is equal and the phase is opposite; the peak-to-peak amplitude of the radio frequency applied to each pair of adjacent cylindrical electrode rods in the cylindrical electrode rod group 6 is equal and the phase is opposite; the applied radio frequency is 0.5-5MHz, and the peak-to-peak value of the radio frequency is 10-500V.

[0037] In this embodiment, the thickness of the double-aperture electrode 1 is 2mm; the diameter of the through hole is 1mm; the dimensions of each rectangular electrode rod in the rectangular electrode rod group 5 are consistent, with a length of 20mm, a width of 10mm, a thickness of 4mm, and a circumference radius A of 20mm; the dimensions of each cylindrical electrode rod in the cylindrical electrode rod group 6 are consistent, with a length of 110mm, a radius of 6mm, and a circumference radius B of 11mm; the electrodes in the double-aperture electrode 1, rectangular electrode rod group 5, and cylindrical electrode rod group 6 are stainless steel electrodes. The DC voltages applied to the double-aperture electrode 1, rectangular electrode rod group 5, and cylindrical electrode rod group 6 are 11V, 8V, and 3V, respectively; the peak-to-peak amplitude of the radio frequency applied to each pair of adjacent rectangular electrode rods in the rectangular electrode rod group 5 is equal and the phase is opposite; the peak-to-peak amplitude of the radio frequency applied to each pair of adjacent cylindrical electrode rods in the cylindrical electrode rod group 6 is equal and the phase is opposite; the applied radio frequency is 1.0MHz, and the peak-to-peak value is 200V. One end face of each rectangular electrode rod is located in the same plane, and one end face of each cylindrical electrode rod is located in the same plane.

[0038] Furthermore, a mass analyzer is installed on the outside of the vacuum chamber 4, and the sample input end of the mass analyzer is connected to the ion output port 7. The mass analyzer is a time-of-flight mass analyzer, a quadrupole mass analyzer, an ion trap mass analyzer, a sector magnetic field mass analyzer, or an ion cyclotron resonance mass analyzer. The gas pressures of ionization source I2 and ionization source II3 are independent of each other, and they are photoionization source and proton transfer ionization source, respectively.

[0039] The axial center lines of the two circular through holes on the double-hole electrode 1 are on the same plane as the axial center line of the ion output port; the plane containing circle A and the plane containing circle B are parallel to each other, and the vertex of the double-hole electrode 1, the center of circle A, the center of circle B and the axial center line of the ion output port are all collinear; the gas pressure in the vacuum chamber 4 is maintained at 1 Pa.

[0040] Example

[0041] like Figure 1 As shown, the present invention provides a spatially distributed dual ionization source device. During operation, the DC voltages applied to the dual-aperture electrode 1, the rectangular electrode rod group 5, and the cylindrical electrode rod group 6 are 11V, 8V, and 3V, respectively. The radio frequency applied to the rectangular electrode rod group 5 and the cylindrical electrode rod group 6 is 1.0MHz, the radio frequency peak-to-peak value is 200V, and the vacuum in the vacuum chamber 4 is maintained at 1Pa.

[0042] The transmission efficiency of the dual-source structure was simulated using SIMION software under the above conditions, such as... Figure 2As shown, the mass-to-charge ratio of the ions used was 100, the number was 200, the ion incident angle was 45°, and the final transmission efficiency was 93%. This indicates that the combination of the short quadrupole rectangular rod and the quadrupole cylindrical rod can achieve efficient focusing and transmission of ions over a wide range after the ionization source, thereby ensuring the sensitivity of the spatially distributed dual ionization source.

[0043] In this invention, the combination of a short quadrupole rectangular rod and a quadrupole cylindrical rod achieves efficient focusing and transport of ions over a wide range after ionization, thus ensuring the sensitivity of the spatially distributed dual ionization sources. Furthermore, the gas pressures of the two spatially distributed ionization sources are independent, allowing for combinations of various ionization sources. This enables sample ionization under different ionization modes, significantly enhancing qualitative capabilities and effectively broadening the application range.

[0044] The above description is merely an embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, extensions, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A spatially distributed dual ionization source device, characterized in that, It includes a double-hole electrode (1), ionization source I (2), ionization source II (3), vacuum chamber (4), rectangular rod group (5) and cylindrical rod group (6), wherein the vacuum chamber (4) is provided with a double-hole electrode (1) at one end and an ion output port (7) at the other end; The double-hole electrode (1) has two circular through holes. Ionization source I (2) and ionization source II (3) are respectively set at the outer ends of the two circular through holes of the double-hole electrode (1). Rectangular rod group (5) and cylindrical rod group (6) are arranged in the vacuum cavity (4) at intervals along the ion transport direction. DC voltages are applied to the double-hole electrode (1), the rectangular electrode rod group (5), and the cylindrical electrode rod group (6), decreasing sequentially. Radio frequency voltages are also applied to the rectangular electrode rod group (5) and the cylindrical electrode rod group (6). The dual-hole electrode (1) is a conical structure that protrudes outward, and the conical structure is coaxial with the ion output port (7). The two circular through holes are symmetrical about the horizontal plane passing through the vertex of the double-hole electrode (1), and the central axis of the two circular through holes is on the same plane as the vertex of the double-hole electrode (1) and the axial center line of the ion output port (7). The rectangular rod group (5) includes at least four rectangular electrode rods that are evenly distributed along the circumference and arranged parallel to the axis of the double-hole electrode (1), and the number of rectangular electrode rods is even. On the cross-section of the rectangular rod group (5), the centers of the plurality of rectangular electrode rods are located on the same circumference A; the wide face of each rectangular electrode rod is perpendicular to the line connecting the center of circumference A and the center point of the rectangular electrode rod on circumference A; The cylindrical rod group (6) includes at least four cylindrical electrode rods that are evenly distributed along the circumference and arranged parallel to the axis of the double-hole electrode (1), and the number of cylindrical electrode rods is even. On the cross-section of the cylindrical rod assembly (6), the centers of the plurality of cylindrical rod assemblies (6) are located on the same circumference B, and the radius of circumference B is smaller than the radius of circumference A.

2. The spatially distributed dual ionization source device according to claim 1, characterized in that, The thickness of the double-hole electrode (1) is 2-4 mm; the diameter of the circular through hole is 1-2 mm.

3. The spatially distributed dual ionization source device according to claim 1, characterized in that, The ionization source I (2) and the ionization source II (3) are located along the central axis of the two circular through holes of the double-hole electrode (1) and are in contact with the outer surface of the double-hole electrode (1).

4. The spatially distributed dual ionization source device according to claim 1, characterized in that, The rectangular electrode rods in the rectangular electrode rod group (5) have the same dimensions: a length of 10-30 mm, a width of 5-15 mm, a thickness of 2-6 mm, and a radius of 10-20 mm for circumference A. The cylindrical electrode rods in the cylindrical electrode rod group (6) have the same dimensions: a length of 60-120 mm, a radius of 4-8 mm, and a radius of 10-15 mm for circumference B. The electrodes in the double-hole electrode (1), rectangular electrode rod group (5) and cylindrical electrode rod group (6) are conductive metals or have a conductive metal layer plated on their surface.

5. The spatially distributed dual ionization source device according to claim 1, characterized in that, The DC voltage applied to the double-hole electrode (1), the rectangular electrode rod group (5) and the cylindrical electrode rod group (6) decreases sequentially to form a DC gradient electric field with a gradient voltage of 1-20 V / cm. The peak-to-peak amplitude of the radio frequency applied to each pair of adjacent rectangular electrode rods in the rectangular electrode rod group (5) is equal and the phase is opposite; the peak-to-peak amplitude of the radio frequency applied to each pair of adjacent cylindrical electrode rods in the cylindrical electrode rod group (6) is equal and the phase is opposite; the applied radio frequency frequency is 0.5-5 MHz and the peak-to-peak value of the radio frequency is 10-500 V.

6. The spatially distributed dual ionization source device according to claim 1, characterized in that, The vacuum chamber (4) is a horizontally placed rectangular cylindrical structure; a vacuum extraction port (8) is provided on the lower side wall of the vacuum chamber (4) near the ion output port (7), and the extraction port (8) is connected to a vacuum pump to maintain the vacuum in the vacuum chamber (4). The gas pressure in the vacuum chamber (4) is maintained between 0.1-2 Pa.

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