Sound-Assisted Focused Ion Mobility Method, Apparatus, and Ion Mobility Spectrometer

Abstract

The present invention belongs to the technical field of ion mobility tubes, and discloses a method, device and ion mobility spectrometry analyzer for acoustic-assisted focusing of ion mobility. The acoustic radiation force generated by the sound field is combined with the traction force generated by the electric field. The electric field provides the traction force for the axial movement of ions, and the sound field provides the binding force for restricting the radial movement of ions. The range and intensity of the radial constraint can be controlled by adjusting the frequency, phase and amplitude of the sound wave. The acoustic-assisted focusing ion mobility method utilizes an ultrasonic standing wave to cause the vibration of the air medium and generate an acoustic radiation force. The ion transport device of the present invention that utilizes sound waves to assist ion focusing forms a focusing region for restricting ion movement in the cavity of the ion transport device in the form of acoustic standing wave nodes through a simple implementation structure. In this way, the function of ion focusing (restricting the ion movement range) can be achieved without introducing a complex electric control system and without introducing additional interfering electric fields into the original ion transport device.

Description

Technical Field

[0001] The present invention belongs to the technical field of ion migration tubes, and particularly relates to a sound-assisted focusing ion migration method, device and ion migration spectrometer. Background Art

[0002] At present, analytical chemistry instruments usually analyze the ionic form of substances, such as ion mobility spectrometers. The ion transport device is an indispensable key component in these instruments, usually composed of coaxial multi-piece metal ring electrodes. By controlling the potential applied to the electrodes, a specific electric field is formed in the tube cavity to achieve the function of ion transport. In addition to the action of the electric field, the collision, diffusion, Coulomb repulsion, etc. between ions and neutral gas molecules are all factors affecting ion movement. The combined effect of these actions will cause the cross-section of ion transport to change, and thus inevitably collide with the wall of the transport channel, resulting in ion consumption. In order to avoid the adverse effects such as the increase in motion uncertainty caused by the change in cross-sectional shape, the loss of ion quantity, and the contamination of impurities on the tube wall, ion focusing technology is usually used to constrain and improve the cross-sectional shape of ion transport, bringing the beneficial effects of enhancing the sensitivity and resolution of the instrument.

[0003] Traditional methods for achieving ion focusing usually involve applying an additional electric field that constrains the lateral movement of ions in the ion transport device. The focusing electric field is usually achieved by radio frequency application. This ion transport device with focusing function is usually also called an ion lens. At present, although the ion lens device can achieve the function of ion focusing, it often requires a precise electronic control system, accurate timing relationship, and a large and complex device structure, which is particularly cumbersome for system construction and also increases the volume and cost of the instrument. In addition, since both the ion focusing behavior and the ion transport behavior need to be controlled by an electric field, it is necessary to make a trade-off between the focusing and transport functions of the transport device. Often, in order to achieve the focusing effect, the transport electric field will be changed, ultimately affecting the instrument performance.

[0004] Through the above analysis, the problems and defects existing in the prior art are as follows:

[0005] (1) At present, the construction of the ion lens device is cumbersome, the volume of the instrument is large, and the cost is high.

[0006] (2) Making a trade-off between the focusing and transport functions of the transport device causes a change in the transport electric field, ultimately affecting the instrument performance.

[0007] The difficulty in solving the above problems and defects is:

[0008] (1) How to find a method or device with a simple structure and low cost to focus ions;

[0009] (2) How to find a method or device that can minimize the impact on the ion transport function, take into account the ion focusing function, and does not affect the ion transport electric field.

[0010] (3) How to simplify the device as much as possible while taking into account ion transport and focusing.

[0011] The significance of solving the above problems and defects is as follows:

[0012] (1) While not weakening the ion transport function, ion focusing is achieved, enabling the separate and independent control of the two functions of ion transport and focusing. This can improve the efficiency of the ion transport device, control the movement range of ions, and ultimately greatly improve the performance of the instrument, enhance the sensitivity of the instrument, and improve the resolution of the instrument under the condition of the same-sized tube cavity.

[0013] (2) If ions touch the inner wall of the migration tube, they will collide with the wall, resulting in the disappearance of the ion charge. At this time, the ions will adhere to the migration tube wall, and unnecessary interference in terms of species or quantity will be introduced due to the previously adhered ions during the next detection. This solution can limit the movement range of the ion group, prevent ions from colliding with the migration tube wall, neither losing ions nor causing secondary pollution to the internal environment of the migration tube.

[0014] (3) Without changing the ion transport electric field, ion focusing is achieved, and the ion transport and focusing are independently controlled, enabling the separate adjustment of the ion transport and focusing functions without interfering with each other. Thus, the electric field does not need to be enhanced due to the influence of the focusing function, further enhancing the control ability of the ion forward direction, improving the signal intensity of the instrument, and reducing the measurement error between ions with different mobilities. The complex radio frequency electronic control ion lens system can be simplified, reducing the volume and cost of the instrument. Summary of the Invention

[0015] In view of the problems existing in the prior art, the present invention provides an acoustic-assisted focusing ion migration method, device, and ion mobility spectrometry analyzer.

[0016] The present invention is implemented as follows. An acoustic-assisted focusing ion migration method combines the acoustic radiation force generated by the sound field with the traction force generated by the electric field. The electric field is responsible for the axial movement of ions, and the sound field is responsible for the radial constraint of ions; the radial constraint is controlled by adjusting the frequency, phase, and amplitude of the sound wave.

[0017] Furthermore, the acoustic-assisted focusing ion migration method utilizes ultrasonic standing waves to cause the vibration of the air medium and generate acoustic radiation force. As long as the effect of using the sound field to generate standing waves to constrain the transverse distribution of the ion movement direction in the atmospheric environment is considered within the protection scope of this patent.

[0018] Furthermore, the acoustic-assisted focused ion migration method utilizes the effect of an ultrasonic standing wave at the center position of the ring to generate a force that squeezes the surrounding gas inward towards the center of the ring. A stacked ring array is formed using multiple ring transducer module structures to create an ion transport channel, and under the action of an electric field, ions are sent into the device for transport. Taking the arrangement of the ultrasonic transducers with a central ring as an example, in actual operation, the scope of rights of this patent is not limited to the form of a ring, but takes the form of a migration tube as the core. If the migration tube is flat, the acoustic radiation force generated by two transducers for the flat plate can be used for constraint.

[0019] Furthermore, the ring transducer module emits ultrasonic waves to form a standing wave, causing the air medium to generate an acoustic radiation force, which converges from all around towards the center position of the ring, generating a gas pressure that is inward towards the center of the ring near the center of the ring. The generated pressure exerts a force on the passing ions towards the center position of the ring.

[0020] Furthermore, the stacked ring array is composed of multiple ring transducer modules. Insulating materials are used to connect between the bottom plates of each ring. The central positions of each ring are on the same straight line, and this straight line is the ion transport channel. The direction in which the ultrasonic transducer emits ultrasonic signals is perpendicular to this ion transport direction. Each ring is a ring transducer module device, and multiple connected rings form an ion transport channel. Inside the channel, ions are subject to the air pressure from the channel wall towards the channel center during transmission and are transmitted along the channel without loss.

[0021] Furthermore, for the acoustic-assisted focused ion migration method, an electric field is applied. Ions enter the above-mentioned stacked ring array under the action of the electric field and move forward in the direction of the electric field under the action of the electric field force. At the same time, under the gas pressure generated by ultrasonic focusing, they always remain on the channel at the center position of the ring and do not spread to the surroundings, forming a stable ion beam and being transmitted from one side of the device to the other side without loss.

[0022] Furthermore, the acoustic-assisted focused ion migration method specifically includes:

[0023] In the first step, an ultrasonic standing wave signal is emitted towards the ion group from all around the ion group using an array in the shape of a ring.

[0024] In the second step, the voltage, center frequency, and phase parameters of the ultrasonic standing wave signal in the ring array are adjusted so that the ultrasonic standing wave signal generates an acoustic radiation force towards the center position of the ring. Under the action of the acoustic radiation force, the air forms an inward pressure on the center position of the ring, causing the ions to converge towards the center position of the ring and preventing diffusion caused by radial movement.

[0025] In the third step, multiple ring arrays are connected such that the center positions of the respective ring arrays are superimposed to form an ion transport channel. The channel causes ions to be squeezed towards the vicinity of the center position of each ring by the acoustic radiation force from all around during the transport process.

[0026] In the fourth step, a plurality of electrode migration rings are added to the ion channel. Different voltages are applied to the respective migration rings to generate a potential difference and form an electric field, such that the ions are transported within the ion channel under the action of the generated electric field force.

[0027] Another object of the present invention is to provide an acoustic-assisted focusing ion migration device for implementing the acoustic-assisted focusing ion migration method. The acoustic-assisted focusing ion migration device is composed of several annular ultrasonic transmitting devices and an ion transport power supply device connected alternately.

[0028] The annular ultrasonic transmitting device emits ultrasonic waves for focusing to generate air pressure to suppress the diffusion of ions. The ion transport power supply device generates an electric field to transport the ions, and an ion transport channel is formed by superposition at the center position of each device.

[0029] The ultrasonic transmitter is fixed on a ring-shaped bottom plate. Every two ultrasonic transmitters face each other, and the ultrasonic transmitters are symmetrically arranged on the ring-shaped floor.

[0030] Furthermore, the acoustic-assisted focusing ion migration device further includes a power supply and control device. The power supply and control device is connected by a wire and supplies power to the ultrasonic transducer, controls the applied voltage value and the phase of the emitted ultrasonic wave. The power supply device applies a voltage to the migration ring to form an electric field for ion transport.

[0031] When the ultrasonic transducer is installed and fixed, it should be perpendicular to the ion transport direction. The ring shape described in the steps is just one form of orthogonality. There may also be vertical orthogonality in transmission forms such as cylindrical transmission, flat plate transmission, cubic transmission, etc. The direction of the emitted ultrasonic signal should be perpendicular to the ion transport direction.

[0032] Another object of the present invention is to provide an ion mobility spectrometry analyzer. The ion mobility spectrometry analyzer is equipped with the acoustic-assisted focusing ion migration device. Under the action of an electric field, an ion source is transported through the acoustic-assisted focusing ion migration device, and the ion beam is transported to the mass analyzer without loss.

[0033] Combining all the above technical solutions, the advantages and positive effects of the present invention are as follows: The present invention is an ion transport tube with a focusing function. The migration tube uses the acoustic radiation force generated by sound waves in the atmospheric environment to limit the movement range of ions, enabling spatial focusing of ion clusters, thereby constraining the ion transport cross-section, reducing ion transport losses, and reducing cross-contamination caused by ion collisions during ion transport.

[0034] In the industry, the movement range of ions is generally restricted by means of a constraint electric field or a radio frequency ion lens. This traditional method requires a series of supporting power supply systems and specially designed migration electrode structures. At the same time, when in use, the original electric field needs to be changed to cooperate in order to achieve the function of restricting ion movement. It not only has high costs, complex mechanisms, and great implementation difficulties, but also cannot achieve good ion transport effects.

[0035] The present invention uses the radial acoustic radiation force to focus ions and the axial electric field force to transport ions. It no longer uses the method of applying an electric field alone to focus and transport ions, overcoming the technical obstacle of having to make a trade-off between the efficiency of the transport and focusing functions when using an electric field alone, and the control of the transport and focusing functions is relatively independent. It not only overcomes the problem of low ion transport efficiency caused by diffusion during ion beam transport in the prior art, but also makes up for the shortcoming that the transport and focusing functions of ions cannot have both. It can achieve high-precision gas-phase ion control and has high industrial utilization value for the analytical instrument industry, especially for ion mobility spectrometers.

[0036] The ion transport device of the present invention that uses sound waves to assist ion focusing forms a constraint ion movement focusing region in the lumen of the ion transport device in the form of a standing sound wave through a simple implementation structure; achieving the ion focusing function in this way does not require a complex electronic control system and will not introduce additional interfering electric fields into the original ion transport device.

[0037] Compared with the prior art, the present invention has the following advantages:

[0038] (1) Compared with existing ion lenses and migration tube ion mobility spectrometers, during ion transport, it is possible to prevent ion losses caused by ion radial diffusion, enabling more ions to be transported from the ion source to the mass analyzer, greatly improving the ion transport efficiency.

[0039] (2) Since ion contact with the tube wall will cause residues, and thus may carry residual ions when transporting ions of another substance, the ion transport method and device of the present invention can effectively reduce the carry-over contamination caused by ion collisions with the wall.

[0040] (3) The present invention can control the focusing area by changing the form of sound waves, replacing the constraint electric field, and can be used under atmospheric pressure.

[0041] (4) The design of the present invention is simple, relatively easy to implement, and can meet the requirements in different specific situations by adjusting the size of the device and the connection method. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a flowchart of the acoustic-assisted focused ion migration method provided by an embodiment of the present invention;

[0043] Figure 2 is a schematic diagram of an embodiment of the acoustic-assisted focused ion migration device provided by an embodiment of the present invention;

[0044] Figure 3 is a schematic diagram of an embodiment of the annular ultrasonic generation module provided by an embodiment of the present invention;

[0045] Figure 4 is a working principle diagram of the acoustic-assisted focused ion migration device provided by an embodiment of the present invention;

[0046] Figure 5 is a finite element simulation result diagram of the annular sound field model in Embodiment 1 provided by an embodiment of the present invention;

[0047] Figure 6 is a schematic structural diagram of Embodiment 2 provided by an embodiment of the present invention;

[0048] In the figure: 1. Annular ultrasonic transmitting device; 2. Power supply device for ion transmission; 3. Ion transmission channel; 4. Ultrasonic transmitter (ultrasonic transducer); 5. Position where ions converge due to the acoustic radiation force generated by ultrasonic focusing; 6. Electric field applied to ion transmission; 7 and 13. Placement positions of transducers; 14. Figure 5 Sound field distribution at the center of the ring in the placement mode; 8. Upper transducer; 9. Lower transducer; 10. Ion inlet; 11. Ion outlet; 12. Constraint range of the sound field. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0049] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0050] In view of the problems existing in the prior art, the present invention provides an acoustic-assisted focused ion migration method, device and ion migration spectrometer ion migration spectrum analyzer, which will be described in detail below with reference to the accompanying drawings.

[0051] Embodiment 1:

[0052] As Figure 1As shown in the figure, the acoustic-assisted focusing annular ion migration method provided by the present invention includes the following steps. The ion migration tube used is an annular structure in a "sandwich" stack as shown in Figure 2 the "sandwich" stack shown below:

[0053] S101: Add multiple electrode migration rings in the ion channel, and apply different voltages to each migration ring to generate a potential difference to form an electric field, so that ions are transported in the ion channel under the action of the generated electric field force.

[0054] S102: Use an annular array in the ion migration tube composed of rings to emit ultrasonic standing wave signals around the ion group to be constrained.

[0055] S103: Adjust parameters such as the voltage, center frequency, and phase of the ultrasonic standing wave signal in the annular array, so that the ultrasonic standing wave signal generates an acoustic radiation force towards the center position of the ring. Under the action of the acoustic radiation force, the air forms an inward pressure on the center position of the ring, which can make the ions converge towards the center position of the ring to prevent diffusion caused by radial movement.

[0056] S104: Connect multiple annular arrays, so that the center positions of each annular array are superimposed to form an ion transmission channel. This channel can make the ions be squeezed towards the vicinity of the center position of each ring by the acoustic radiation force around during the transmission process, thereby preventing ion loss caused by radial diffusion during ion transmission.

[0057] Ordinary technical personnel in the industry can also implement the acoustic-assisted focusing ion migration method provided by the present invention using other steps. Figure 1 The acoustic-assisted focusing ion migration method provided by the present invention is only a specific embodiment.

[0058] As shown in Figure 2 the figure, the acoustic-assisted focusing ion migration device provided by the present invention is composed of several annular ultrasonic emission devices 1 and power supply devices 2 for ion transmission connected alternately. The number, size, and the distance between the annular ultrasonic emission devices 1 and the power supply devices 2 for ion transmission can be adjusted according to specific requirements. The annular ultrasonic emission devices 1 emit ultrasonic waves to focus and generate air pressure to suppress the diffusion of ions, and the power supply devices for ion transmission generate an electric field to transport the ions. An ion transmission channel 3 is formed by superimposing at the center position of each device.

[0059] An embodiment of the annular ultrasonic transducer module of the present invention is as shown in Figure 3 the figure. Fix the ultrasonic wave emitter 4 on the bottom plate in the shape of a ring. Every two ultrasonic wave emitters are opposite to each other, and the ultrasonic wave emitters 4 are symmetrically arranged on the bottom plate in the shape of a ring. The inner diameter of the bottom plate in the shape of a ring and the number of ultrasonic wave emitters 4 can be adjusted according to specific requirements.

[0060] The working principle diagram of the acoustic-assisted focusing ion mobility device of the present invention is as Figure 4 shown. Several ultrasonic transmitters 4 face each other and emit ultrasonic signals towards the center of the ring to form a standing wave. The ultrasonic focusing generates an air pressure that can confine the transmitted ions at the position 5 of each annular ultrasonic transmitting device 1, preventing the diffusion of ions. Several annular ultrasonic transmitting devices 1 and the power supply device 2 for ion transmission are alternately connected. Under the action of the electric field force of the electric field 6 generated by the power supply device, the ions are transmitted along the ion transmission channel 3.

[0061] A basic embodiment of the present invention utilizes the principle of ultrasonic energy conversion. The ultrasonic standing wave acts on the center position of the ring to generate a force that squeezes the surrounding gas towards the center of the ring. A plurality of ring energy conversion module structures are used to form a stacked ring array to form an ion transmission channel, and under the action of an electric field, the ions are sent into the device for transmission. The embodiments of the present invention include but are not limited to this. The goal is to form an acoustic radiation force at the center to suppress the radial movement of ions, and it may include all structures that complete this function.

[0062] The working principle of the ring energy conversion module of the acoustic-assisted focusing ion mobility device provided by the present invention is that the ring ultrasonic transmitter emits ultrasonic waves to form a standing wave, causing the air medium to generate an acoustic radiation force, which converges from all around to the center position of the ring, generating a gas pressure near the center of the ring that acts inward towards the center of the ring. The generated pressure can exert a force on the passing ions towards the center position of the ring, preventing the ions from deviating from the transmission channel due to diffusion.

[0063] The stacked ring ultrasonic energy conversion array of the present invention. The stacked ring array is composed of a plurality of ring energy conversion modules. Insulating materials are used to connect between the bottom plates of each ring. The center positions of each ring are on the same straight line, and this straight line is the ion transmission channel. The direction in which the ultrasonic transducer emits ultrasonic signals is perpendicular to this ion transmission direction. Each ring is the above-mentioned ring energy conversion module device. Connecting multiple such devices can form an ion transmission channel. Inside the channel, when the ions are transmitted, they can be subjected to an air pressure from the channel wall towards the center of the channel and cannot diffuse to the surroundings, so as to be transmitted along this channel without loss.

[0064] The principle of the acoustic-assisted focusing ion mobility device provided by the present invention is that an electric field is applied at both ends of the device, so that the ions enter the above-mentioned stacked ring array under the action of the electric field, and move forward in the direction of the electric field under the action of the electric field force. At the same time, under the gas pressure generated by the ultrasonic focusing of the device, they always remain on the channel at the center position of the ring and do not diffuse to the surroundings, forming a stable ion beam and being transmitted from one side of the device to the other side without loss.

[0065] The acoustic-assisted focusing ion mobility device provided by the present invention further includes a power supply and control device, which is connected through a wire to supply power to the ultrasonic transducer, control the applied voltage value, the phase of the emitted ultrasonic wave, etc. The power supply device can also apply a voltage to the migration ring to form an electric field for ion transmission.

[0066] The material of the circular ring bottom plate used in the present invention must be a material with relatively high hardness, and at the same time, the position where the ultrasonic transducer is fixed requires relatively high precision.

[0067] When the ultrasonic transducer used in the present invention is installed and fixed, it should be perpendicular to the direction of ion transmission, and the direction of the emitted ultrasonic signal should be perpendicular to the direction of ion transmission.

[0068] The voltage of the ultrasonic transducer used in the present invention and the central frequency of the emitted ultrasonic wave can be adjusted according to specific requirements, and can be adjusted according to specific requirements to obtain more ideal results.

[0069] The size of the circular ring ultrasonic transducer device of the present invention can be adjusted according to specific requirements, and the number of circular rings in the stacked ring ultrasonic transducer array and the number of ultrasonic transducers in each circular ring ultrasonic energy module can also be adjusted according to specific requirements.

[0070] The device of the present invention can be applied in an ion mobility spectrometry analyzer. Under the action of an electric field, the ion source is transmitted through the device, and the ion beam is transmitted to the mass analyzer without loss.

[0071] The acoustic-assisted focusing ion mobility method provided by the present invention uses an ultrasonic transducer to convert the input electric power into mechanical power, that is, in the form of ultrasonic waves. Ultrasonic waves with the same emission frequency and opposite propagation directions form a standing wave, forming interference to cause the air medium to vibrate and generate acoustic radiation force, causing a force towards the center in the surrounding gas. When ions pass through the position, the ions are restricted at the central position by the force exerted by the surrounding gas and cannot diffuse, thereby achieving the purpose of preventing ion radial diffusion and causing ion loss.

[0072] To implement the method of the present invention, it is first necessary to enable ions to receive a uniform gas pressure from the surrounding gas at a specific position in each circular ring ultrasonic transducer module. To achieve this goal, the central frequency, phase, etc. of the ultrasonic waves emitted by the ultrasonic transducer need to be adjusted accordingly. Some lighter objects can be used for testing so that they can be suspended at a specific position. After debugging the circular ring ultrasonic transducer module, the stacked ring array can be connected. Each circular ring module of the stacked ring array generates an inward gas pressure near the central position, and the superimposed gas pressure forms a channel. Under the action of the electric field, ions pass through the channel and are squeezed by the air pressure in the channel without diffusing towards the boundary of the electric field, and the ion beam is transmitted along a straight line from one end to the other end of the stacked ring array under the above action.

[0073] The present invention can be applied as an ion lens system in an ion mobility spectrometer and a mass spectrometer, greatly improving the transmission efficiency when the ion beam of the ion source is transmitted to the mass analyzer. The present invention preferably overcomes the problem of low ion transmission efficiency caused by diffusion during ion beam transmission in the prior art and has high industrial utilization value.

[0074] Example 2:

[0075] A flat ion mobility tube is provided. The mobility tube used in this example is a flat ion mobility tube as shown in (a) of Figure 6 and (b) of Figure 6 Ions pass through from one end of the tube cavity to the other end. Without restricting the ion movement range, the ions will collide with the tube wall, thereby reducing the ion transmission efficiency. In the embodiment of the present invention, an acoustic-assisted focusing method is adopted to restrict the ion transmission range. Ultrasonic transducers are respectively placed at the upper and lower ends of the flat mobility tube, thus forming a sound field constraint range in the middle of the mobility tube. Within this range, the distribution of ions in the transverse direction is restricted by the acoustic radiation force, so that they will not collide with the tube wall of the mobility tube, achieving the advantage of improving the transmission efficiency required by the design. The ultrasonic transducers include: an upper transducer 8 and a lower transducer 9. The left side of the ultrasonic transducers is the ion inlet 10, the right side is the ion outlet 11, and the sound field constraint range 12 is between the upper transducer 8 and the lower transducer 9.

[0076] The technical effects of the present invention will be described in detail below in combination with simulations.

[0077] In Example 1, in the described annular sound field model, if 7 transducers are distributed on the cross-section of the mobility tube, the following results of the obtained ambient sound field distribution can be obtained through finite element simulation as shown in Figure 5 where 7-13 are the placement positions of the transducers, 1 is still the sound constraint ring as consistent with the previous text, and 14 is the sound field distribution at the center of the ring obtained by adopting 40 kHz and an amplitude of 1 μm in this placement mode. It can be seen that the sound pressure in the central region is relatively low, and the sound pressure at the periphery radiates towards the center, generating a sound pressure source that converges the ions. This simulation result can prove that the ions can be compressed in the central region of the mobility ring by the circular ultrasonic transducer placement method.

[0078] In the description of the present invention, unless otherwise specified, "a plurality of" means two or more; the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, terms such as "first", "second", "third", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0079] As described above, the above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A sound-assisted focusing ion migration method, characterized in that, The sound-assisted focused ion migration method combines the acoustic radiation force generated by the sound field with the traction force generated by the electric field. The electric field is responsible for the axial movement of ions, and the sound field is responsible for the radial confinement of ions. The radial confinement is controlled by adjusting the frequency, phase, and amplitude of the sound wave. The sound-assisted focused ion migration method uses the action of ultrasonic standing waves at the central position to generate a force that squeezes the surrounding gas towards the center. A plurality of transducer module structures are used to form a stacked ring array to form an ion transport channel, and under the action of an electric field, ions are sent into the ion transport channel for transmission. The transducer module emits ultrasonic waves to form standing waves, causing the air medium to generate acoustic radiation force, which converges from all around towards the central position of the ring, generating a gas pressure that is directed inwards towards the center near the center of the ring. The generated pressure exerts a force on the passing ions towards the central position of the ring.

2. The acoustic-assisted focusing ion mobility method according to claim 1, wherein The sound-assisted focused ion migration method uses ultrasonic standing waves to cause the air medium to vibrate and generate acoustic radiation force.

3. The ion mobility method with acoustic assistance focusing as claimed in claim 1, wherein The stacked ring array is composed of a plurality of ring transducer modules. Insulating materials are used to connect between the bottom plates of each ring. The central positions of each ring are on the same straight line, which is the ion transport channel. The direction of the ultrasonic signal emitted by the ultrasonic transducer is perpendicular to this ion transport direction. Each ring is a ring transducer module device, and a plurality of them are connected to form an ion transport channel. Inside the channel, ions are subjected to the air pressure from the channel wall towards the channel center during transmission and are transmitted along the channel without loss.

4. The acoustic-assisted focusing ion mobility method according to claim 1, wherein, The sound-assisted focused ion migration method applies an electric field. Ions enter the stacked ring array under the action of the electric field and are transmitted forward in the direction of the electric field under the action of the electric field force. At the same time, under the gas pressure generated by ultrasonic focusing, they always remain on the channel at the center of the ring and do not spread outwards, forming a stable ion beam and being transmitted from one side of the device to the other side without loss.

5. The acoustic-assisted focusing ion mobility method according to claim 1, wherein The sound-assisted focused ion migration method specifically includes: First step, use an array in the shape of a ring to emit ultrasonic standing wave signals towards the ion group around the ion group to be confined. Second step, adjust the voltage, central frequency, and phase parameters of the ultrasonic standing wave signals in the ring array so that the ultrasonic standing wave signals generate acoustic radiation force towards the central position of the ring. Under the action of the acoustic radiation force, the air forms an inward pressure on the central position of the ring, causing the ions to converge towards the central position of the ring to prevent diffusion caused by radial movement. Third step, connect a plurality of ring arrays so that the central positions of each ring array are superimposed to form an ion transport channel. The channel causes the ions to be squeezed towards the central positions of each ring near the center during transmission under the acoustic radiation force from all around. Fourth step, use a plurality of electrode migration rings added in the ion channel. Different voltages are applied to each migration ring to generate a potential difference to form an electric field, so that the ions are transmitted in the ion channel under the action of the electric field force generated.

6. An acoustic-assisted focusing ion mobility device for implementing the acoustic-assisted focusing ion mobility method according to any one of claims 1 to 5, characterized in that, The sound-assisted focused ion migration device is composed of several ring-shaped ultrasonic emission devices and an electrifying device for ion transmission connected alternately. The annular ultrasonic emission device emits ultrasonic waves to generate air pressure for suppressing the diffusion of ions, and the ion transmission power supply device generates an electric field to transmit the ions. An ion transmission channel is formed by superposition at the central position of each device. The ultrasonic wave emitters are fixed on the bottom plate in a ring shape, with every two ultrasonic wave emitters facing each other and symmetrically arranged on the bottom plate in a ring shape.

7. The acoustic-assisted focusing ion mobility device according to claim 6, wherein, The acoustic-assisted focusing ion migration device further includes a power supply and control device. The power supply and control device is connected through a wire to supply power to the ultrasonic transducer, control the applied voltage value and the phase of the emitted ultrasonic wave, and the power supply device applies a voltage to the migration ring to form an electric field for ion transmission. When the ultrasonic transducer is installed and fixed, it should be perpendicular to the direction of ion transmission, and the direction of the emitted ultrasonic signal should be perpendicular to the direction of ion transmission.

8. An ion mobility spectrometry analyzer, characterized in that, The ion mobility spectrometry analyzer is installed with the acoustic-assisted focusing ion migration device as described in claim 6. Under the action of an electric field, the ion source is transmitted through the acoustic-assisted focusing ion migration device, and the ion beam is transmitted to the mass analyzer without loss.

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