SUMMERY OF THE UTILITY MODEL
Accordingly, there is a need to overcome the drawbacks of the prior art and to provide an atmospheric pressure ionization mass spectrometer and an ion guide transmission apparatus, which not only can increase the mass range of guided ions, but also can improve the guiding efficiency.
The technical scheme is as follows: an ion guide transport device, comprising: the device comprises a cavity, a lead-in electrode is arranged at the front end of the cavity and provided with a lead-in central hole, a lead-out electrode is arranged at the rear end of the cavity and provided with a lead-out central hole; the front section octupole rod and the rear section quadrupole rod are sequentially arranged along the central axis of the cavity;
the pole rod of the front section eight-pole rod comprises more than two first sections which are coaxially arranged in sequence at intervals, and a first insulating part connected between every two adjacent first sections, a first resistor and a first capacitor which are connected in parallel are connected between every two adjacent first sections in series, and the polarities of the adjacent pole rods of the front section eight-pole rod are opposite;
the pole rod of the rear-section quadrupole rod comprises more than two second sections which are coaxially arranged at intervals in sequence, and a second insulating part connected between every two adjacent second sections, wherein a second resistor and a second capacitor which are connected in parallel are connected between every two adjacent second sections in series;
the radio frequency power supply is used for providing two paths of radio frequency voltages with the same amplitude and opposite phases, namely an RF + radio frequency voltage and an RF-radio frequency voltage, a first voltage division capacitor C1, a second voltage division capacitor C2 and a third voltage division capacitor C3 which are connected in series in sequence are connected between the two paths of radio frequency voltages and the ground, a lead between the first voltage division capacitor C1 and the second voltage division capacitor C2 of a branch where the RF + radio frequency voltage is located is electrically connected with a first section segment of the front section of the octupole rod with the positive polarity respectively, a lead between the first voltage division capacitor C1 and the second voltage division capacitor C2 of the branch where the RF-radio frequency voltage is located is electrically connected with a first section of the front section of the octupole rod with the negative polarity respectively, a lead between the first voltage division capacitor C1 and the second voltage division capacitor C2 of the branch where the RF + radio frequency voltage is located is electrically connected with a first section of the rear section of the quadrupole rod with the positive polarity respectively, and a lead between the first voltage division capacitor C1 and the second voltage division capacitor C2 of the branch of the RF-RF voltage is respectively and electrically connected with the first section of the rear section quadrupole rod with the negative polarity.
On the one hand, compared with the traditional single-stage ion guide device, the ion guide transmission device adopts the form that the front section octupole rod and the rear section quadrupole rod are combined and sequentially arranged in the cavity along the central axis of the cavity, so that ions with wider mass range can smoothly enter the front section octupole rod after entering the cavity through the introduction central hole of the introduction electrode, the mass range of the ions captured by the front section octupole rod is wider, the ions with wider mass range are preliminarily focused by the front section octupole rod, the ions with wider mass range after being preliminarily focused enter the rear section quadrupole rod, the ion beams with wider range after being preliminarily focused can be concentrated near the central axis by the rear section quadrupole rod, the focusing effect of the ion beams is better, the ion beams can be easily led out through the extraction central hole of the extraction electrode, namely, the ion mass range of the guidance can be enlarged, the guiding efficiency can also be improved. On the other hand, through setting up the proportional relation of first partial pressure electric capacity C1 and second partial pressure electric capacity C2, can realize that anterior segment eight polar rod and back end quadrupole are predetermined proportional relation, can realize simultaneously that anterior segment eight polar rod and back end quadrupole provide radio frequency voltage for simultaneously with a radio frequency power supply can, make ion guide transmission device's structure comparatively simple, whole volume is less, the cost is lower, and adopt a radio frequency power supply can realize anterior segment eight polar rod and back end quadrupole simultaneously and satisfy best transmission condition (q is 0.2 ~ 0.7, q is the parameter of radio frequency alternating current strength).
In one embodiment, the rf power supply is further configured to provide two DC bias voltages, which are DC1 DC bias voltage and DC2 DC bias voltage, respectively, the DC1 DC bias voltage is applied to the first segment of the front-segment octupole bar, and the DC2 DC bias voltage is applied to the tail segment of the rear-segment quadrupole bar.
In one embodiment, the amplitude of the radio frequency voltage is adjustable, and the amplitude of the direct current bias voltage is adjustable.
In one embodiment, the side wall of the chamber corresponding to the front section octupole rod is provided with a vent for introducing collision gas.
In one embodiment, the length of the first section of the front segment octupole rod is 10 mm-30 mm, the length of the pole rod of the front segment octupole rod is 100 mm-300 mm, and the field radius R1 of the front segment octupole rod is 2 mm-16 mm.
In one embodiment, the ratio of the pole diameter R1 to the field radius R1 of the front segment octupole is 0.35-0.36.
In one embodiment, the length of the second section of the back-end quadrupole is 10mm to 30mm, the length of the pole of the back-end quadrupole is 100mm to 300mm, and the field radius R2 of the back-end quadrupole is 2mm to 16 mm.
In one embodiment, the ratio of the pole rod diameter R2 to the field radius R2 of the rear-section quadrupole is 1.12-1.15.
In one embodiment, the first voltage-dividing capacitor C1 and the second voltage-dividing capacitor C2 are adjustable capacitors with adjustable sizes.
An atmospheric pressure ionization mass spectrometer comprises the ion guide transmission device.
Compared with the traditional single-stage ion guide device, on one hand, the atmospheric pressure ionization mass spectrometer adopts the form that the front section octupole rod and the rear section quadrupole rod are combined and sequentially arranged in the cavity along the central axis of the cavity, so that ions with a wider mass range can smoothly enter the front section octupole rod after entering the cavity through the introduction central hole of the introduction electrode, the mass range of the ions captured by the front section octupole rod is wider, the ions with the wider mass range are preliminarily focused by the front section octupole rod, the ions with the wider mass range after being preliminarily focused then enter the rear section quadrupole rod, the ion beams with the wider mass range can be concentrated near the central axis after being preliminarily focused by the rear section quadrupole rod, the focusing effect of the ion beams is better, the ion beams can be easily led out through the extraction central hole of the extraction electrode, namely, the ion mass range of the guidance can be enlarged, the guiding efficiency can also be improved. On the other hand, through setting up the proportional relation of first partial pressure electric capacity C1 and second partial pressure electric capacity C2, can realize that anterior segment eight polar rod and back end quadrupole are predetermined proportional relation, can realize simultaneously that anterior segment eight polar rod and back end quadrupole provide radio frequency voltage for simultaneously with a radio frequency power supply can, make ion guide transmission device's structure comparatively simple, whole volume is less, the cost is lower, and adopt a radio frequency power supply can realize anterior segment eight polar rod and back end quadrupole simultaneously and satisfy best transmission condition (q is 0.2 ~ 0.7, q is the parameter of radio frequency alternating current strength).
Detailed Description
In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will be able to make similar modifications without departing from the spirit and scope of the present invention.
Referring to fig. 2 and fig. 3, fig. 2 illustrates a side view structure diagram of an ion guide transmission device according to an embodiment of the present invention, and fig. 3 illustrates a schematic structure diagram of an embodiment of the present invention, in which an anterior-segment octupole 20 and a posterior-segment quadrupole 30 of the ion guide transmission device are connected to a radio frequency power source. An embodiment of the utility model provides a pair of ion guide transmission device, ion guide transmission device includes: a chamber 10, a front segment octupole rod 20, a rear segment quadrupole rod 30 and a radio frequency power supply.
The front end of the chamber 10 is provided with a leading-in electrode 11, the leading-in electrode 11 is provided with a leading-in central hole 111, the rear end of the chamber 10 is provided with a leading-out electrode 12, and the leading-out electrode 12 is provided with a leading-out central hole 121. The front-stage octupole rod 20 and the rear-stage quadrupole rod 30 are sequentially disposed along the central axis of the chamber 10.
The pole rod of the front-segment octupole 20 comprises more than two first sections 21 coaxially arranged at intervals in sequence, and a first insulating member (not shown in the figure) connected between two adjacent first sections 21. A first resistor and a first capacitor connected in parallel are connected in series between two adjacent first sections 21, and the polarities of the adjacent poles of the front section octupole 20 are opposite.
The pole rod of the rear-stage quadrupole 30 comprises more than two second sections 31 coaxially arranged at intervals in sequence, and a second insulating member connected between the two adjacent second sections 31. A second resistor and a second capacitor connected in parallel are connected in series between two adjacent second segments 31.
The radio frequency power supply is used for providing two paths of radio frequency voltages with the same amplitude and opposite phases, namely an RF + radio frequency voltage and an RF-radio frequency voltage, and a first voltage division capacitor C1, a second voltage division capacitor C2 and a third voltage division capacitor C3 which are connected in series sequentially are connected between the two paths of radio frequency voltages and the ground. The lead between the first voltage-dividing capacitor C1 and the second voltage-dividing capacitor C2 of the branch where the RF + RF voltage is located is electrically connected to the first segment of the front segment octupole 20 with the positive polarity. The lead between the first voltage-dividing capacitor C1 and the second voltage-dividing capacitor C2 of the branch where the RF-RF voltage is located is electrically connected to the first segment of the front segment of the eight-pole rod 20 with the negative polarity. The lead between the first voltage-dividing capacitor C1 and the second voltage-dividing capacitor C2 of the branch where the RF + radio-frequency voltage is located is electrically connected with the first segment of the rear-segment quadrupole 30 with the positive polarity, and the lead between the first voltage-dividing capacitor C1 and the second voltage-dividing capacitor C2 of the branch where the RF-radio-frequency voltage is located is electrically connected with the first segment of the rear-segment quadrupole 30 with the negative polarity.
Compared with the traditional single-stage ion guide device, on the one hand, the ion guide transmission device adopts the form that the front section eight-pole rod 20 and the rear section four-pole rod 30 are combined and sequentially arranged in the chamber 10 along the central axis of the chamber 10, so that ions with a wider mass range can smoothly enter the front section eight-pole rod 20 after entering the chamber 10 through the introduction central hole 111 of the introduction electrode 11, the mass range of the ions which can be captured by the front section eight-pole rod 20 is wider, the ions with the wider mass range are preliminarily focused through the front section eight-pole rod 20, the ions with the wider range after being preliminarily focused then enter the rear section four-pole rod 30, the ion beams with the wider range after being preliminarily focused can be concentrated near the central axis by the rear section four-pole rod 30, the focusing effect of the ion beams is better, and the ion mass range can be easily increased through the extraction central hole 121 of the extraction electrode 12, the guiding efficiency can also be improved. On the other hand, through setting up the proportional relation of first partial pressure electric capacity C1 and second partial pressure electric capacity C2, can realize that anterior segment eight polar rod 20 and back end quadrupole rod 30 are for predetermineeing the proportional relation, can realize simultaneously for anterior segment eight polar rod 20 and back end quadrupole rod 30 provide radio frequency voltage in step with a radio frequency power supply can, make ion guide transmission device's structure comparatively simple, whole volume is less, the cost is lower, and adopt a radio frequency power supply can realize anterior segment eight polar rod 20 and back end quadrupole rod 30 simultaneously and satisfy best transmission condition (q is 0.2 ~ 0.7, q is the parameter of radio frequency alternating current intensity).
The central axis is a line connecting the central point of the lead-in central hole 111 and the central point of the lead-out central hole 121, and is perpendicular to the lead-in electrode 11 and the lead-out electrode 12, respectively.
It should be noted that the first segment with positive polarity of the front-end octupole 20 refers to the first segment 21 with positive polarity close to the leading electrode 11 in the front-end octupole 20. The first segment of the front-end octupole rod 20 with negative polarity refers to the first segment 21 with negative polarity in the front-end octupole rod 20 close to the leading electrode 11. Likewise, the first segment of the rear segment quadrupole 30 with positive polarity refers to the second segment 31 of the rear segment quadrupole 30 with positive polarity that is close to the lead-in electrode 11. The first segment of the rear quadrupole 30 with negative polarity refers to the second segment 31 of the rear quadrupole 30 with negative polarity that is close to the lead-in electrode 11.
The first resistor and the second resistor may be the same size or different sizes, and are not limited herein. The first resistors of the adjacent first segments 21 may be the same or different in size, and are not limited herein. The size of the second resistor of each adjacent first segment 21 may be the same or different, and is not limited herein.
The first capacitor and the second capacitor may be the same size or different sizes, and are not limited herein. The first capacitors of the adjacent first segments 21 may be the same or different in size, and are not limited herein. The size of the second capacitor of each adjacent first segment 21 may be the same or different, and is not limited herein.
In one embodiment, the rf power supply is further configured to provide a two-way dc bias voltage. The two paths of direct current bias voltages are respectively DC1 direct current bias voltage and DC2 direct current bias voltage, the DC1 direct current bias voltage is applied to the first segment of the front-segment eight-pole rod 20, and the DC2 direct current bias voltage is applied to the tail segment of the rear-segment four-pole rod 30. In this way, the voltage applied by the dc bias voltage to the front-stage octupole 20 and the rear-stage quadrupole 30 is divided by the first resistor and the second resistor, so that a voltage difference is formed in the central axis direction of the ion guiding and transporting device.
In one embodiment, the amplitude of the rf voltage is adjustable, and the amplitude of the dc bias voltage is adjustable.
In one embodiment, the side wall of the chamber 10 corresponding to the front segment octupole 20 is provided with a vent 13, and the vent 13 is used for introducing collision gas. The collision gas is an inert gas that does not react with ions, and specific examples thereof include helium, nitrogen, argon, and the like, and are not limited herein. When collision gas is introduced into the chamber 10 at a position corresponding to the front segment octupole 20, the collision gas can perform the functions of collision and ion cooling, so that the axial kinetic energy and the radial divergence of large-mass ions with large kinetic energy are reduced, and the capture efficiency can be improved.
In one embodiment, the first segment 21 of the anterior segment octupole 20 has a length of 10mm to 30mm, the anterior segment octupole 20 has a pole length of 100mm to 300mm, and the anterior segment octupole 20 has a field radius R1 of 2mm to 16 mm.
Wherein the number of the first segments 21 of the pole of the front segment octupole 20 depends on the length of the pole, the length of the first segment and the length of the first insulator. In addition, the field radius R1 of the anterior segment octopole 20 depends on the diameter of the shock wave (intersecting shock) when the ion expansion is introduced. The field radius R1 of the leading eight-pole rod 20 refers to the radius of the inscribed circle of each pole of the leading eight-pole rod 20.
Furthermore, the ratio of the pole diameter R1 to the field radius R1 of the front segment octupole 20 is 0.35-0.36. Therefore, a better cooling effect can be realized, and the transmission of ions in a wide mass range is facilitated.
In one embodiment, the second segment 31 of the posterior quadrupole 30 has a length in the range of 10mm to 30mm, the posterior quadrupole 30 has a pole length in the range of 100mm to 300mm, and the posterior quadrupole 30 has a field radius R2 in the range of 2mm to 16 mm.
It should be noted that the number of the second segments 31 of the pole of the rear quadrupole 30 depends on the length of the pole, the length of the second segment, and the length of the second insulator. The field radius R2 of the rear quadrupole rod 30 is determined by the diameter (when the extraction center hole 121 is a circular hole) or the width and length (when the extraction center hole 121 is a square). The field radius R2 of the rear quadrupole 30 is the radius of the inscribed circle of each of the poles of the rear quadrupole 30.
Furthermore, the ratio of the pole rod diameter R2 to the field radius R2 of the rear-stage quadrupole 30 is 1.12-1.15. Therefore, a better transmission effect can be realized, and the focusing effect is better.
Referring to fig. 4 and 5, fig. 4 shows a schematic structural diagram of an ion-guiding transmission device according to an embodiment of the present invention when a field radius R1 is equal to a field radius R2, and fig. 5 shows a schematic structural diagram of an ion-guiding transmission device according to an embodiment of the present invention when a field radius R1 is greater than a field radius R2. Compared with the ion guide transport device illustrated in fig. 4, the ion guide transport device illustrated in fig. 5 has a relatively smaller field radius R2, and the field radius R2 is (0.5-1) × R1, so that the beam width of the obtained ion beam is smaller, the aperture of the extraction center hole 121 is smaller, and the focusing effect is better.
In one embodiment, the first voltage-dividing capacitor C1 and the second voltage-dividing capacitor C2 are adjustable capacitors with adjustable sizes. Thus, the first voltage-dividing capacitor C1 and the second voltage-dividing capacitor C2 can be adjusted to adjust the proportional relationship between the first voltage-dividing capacitor C1 and the second voltage-dividing capacitor C2, so that the front-stage octupole 20 and the rear-stage quadrupole 30 can satisfy the optimal transmission conditions (q is 0.2-0.7, q is a parameter of radio frequency alternating current intensity), and the physical states of the ions in the front-stage octupole 20 and the ions in the rear-stage octupole are ensured to be consistent.
The ion guide device of the present embodiment has at least the following advantages: compared with the traditional single-stage ion guide device, the device has the advantages of wider ion mass range, higher transmission efficiency and better vacuum tolerance. The whole device is flexible and variable, can be placed behind an ion source to be independently used as a transmission device, and can also be used for further focusing behind a transmission device such as a focusing lens behind the ion source. The voltage application mode is simple, and the ion guide device can be used alone or together with an ion funnel and an ion lens plasma guide device.
In one embodiment, an atmospheric pressure ionization mass spectrometer comprises an ion guide transport device according to any of the embodiments described above.
Compared with the traditional single-stage ion guide device, on one hand, the atmospheric pressure ionization mass spectrometer adopts the form that the front section octupole rod 20 and the rear section quadrupole rod 30 are combined and sequentially arranged in the chamber 10 along the central axis of the chamber 10, so that ions with a wider mass range can smoothly enter the front section octupole rod 20 after entering the chamber 10 through the introduction central hole 111 of the introduction electrode 11, the mass range of the ions which can be captured by the front section octupole rod 20 is wider, the ions with the wider mass range are preliminarily focused through the front section octupole rod 20, the ions with the wider mass range after being preliminarily focused then enter the rear section quadrupole rod 30, the rear section quadrupole rod 30 can realize that the ion beams with the wider mass range after being preliminarily focused are concentrated near the central axis, the ion beams have better focusing effect, and can easily pass through the extraction central hole 121 of the extraction electrode 12, namely, the ion mass range of the guidance can be enlarged, the guiding efficiency can also be improved. On the other hand, through setting up the proportional relation of first partial pressure electric capacity C1 and second partial pressure electric capacity C2, can realize that anterior segment eight polar rod 20 and back end quadrupole rod 30 are for predetermineeing the proportional relation, can realize simultaneously for anterior segment eight polar rod 20 and back end quadrupole rod 30 provide radio frequency voltage in step with a radio frequency power supply can, make ion guide transmission device's structure comparatively simple, whole volume is less, the cost is lower, and adopt a radio frequency power supply can realize anterior segment eight polar rod 20 and back end quadrupole rod 30 simultaneously and satisfy best transmission condition (q is 0.2 ~ 0.7, q is the parameter of radio frequency alternating current intensity).
The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above examples only represent some embodiments of the present invention, and the description thereof is more specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.
In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.