CN-122029636-A - Dual-frequency power supply system for mass spectrometry

Abstract

An example system includes a set of multipole rod electrodes and an RF generator configured to selectively output a signal voltage at a first frequency or at a second frequency for driving the set of multipole rod electrodes. The system also includes a low frequency transformer assembly and a high frequency transformer assembly. The system further includes a switching circuit configured to connect the RF generator to a low frequency transformer assembly configured to supply a first voltage to outputs coupled to the set of multipole rod electrodes based on the RF voltage when the RF generator outputs the RF voltage at the first resonant frequency, or to a high frequency transformer assembly configured to supply a second voltage to outputs coupled to the set of multipole rod electrodes based on the RF voltage when the RF generator outputs the RF voltage at the second resonant frequency.

Inventors

• M. Koenigsegg

Assignees

• 赛默菲尼根有限责任公司

Dates

Publication Date

20260512

Application Date

20241011

Priority Date

20231011

Claims (20)

1. 1. An apparatus for performing mass spectrometry, the apparatus comprising: A set of multipole rod electrodes; An RF generator configured to selectively output an RF voltage at a first resonant frequency or at a second resonant frequency for driving the set of multipole rod electrodes; a low frequency transformer assembly; high frequency transformer assembly, and A switching circuit configured to: Connecting the RF generator to the low frequency transformer assembly when the RF generator outputs the RF voltage at the first resonant frequency, the low frequency transformer assembly configured to supply a first voltage to an output coupled to the set of multipole rod electrodes based on the RF voltage, Or connecting the RF generator to the high frequency transformer assembly when the RF generator outputs the RF voltage at the second resonant frequency, the high frequency transformer assembly configured to supply a second voltage to the output coupled to the set of multipole rod electrodes based on the RF voltage.
2. 2. The apparatus of claim 1, wherein the switching circuit comprises a first low pass network for filtering power at harmonics of the first resonant frequency and a second low pass network for filtering power at harmonics of the second resonant frequency.
3. 3. The apparatus of claim 2, wherein the first low pass network and the second low pass network provide an impedance transformation between the RF generator and the output.
4. 4. The apparatus of claim 1, further comprising a controller connected to the RF generator and the switching circuit and configured to selectively operate in a first mode or a second mode, wherein: In the first mode, the controller sets the RF generator to output the RF voltage at the first resonant frequency, sets the switching circuit to connect the RF generator and the low frequency transformer assembly, and sets the switching circuit to disconnect the RF generator from the high frequency transformer assembly, and In the second mode, the controller sets the RF generator to output the RF voltage at the second resonant frequency, sets the switching circuit to connect the RF generator and the high frequency transformer assembly, and sets the switching circuit to disconnect the RF generator from the low frequency transformer assembly.
5. 5. The apparatus of claim 1, further comprising a quadrupole rod filter comprising the set of multipole electrodes, and Wherein the first voltage at the first resonant frequency enables the quadrupole rod filter to filter ions in a first range of mass to charge ratios (m/z), and wherein the second voltage at the second resonant frequency enables the quadrupole rod filter to filter ions in a second range of m/z that is lower than the first range of m/z.
6. 6. The apparatus of claim 1, further comprising a quadrupole rod filter comprising the set of multipole electrodes, and Wherein the first voltage at the first resonant frequency enables the quadrupole rod filter to filter ions of a magnitude exceeding a threshold m/z, and wherein the second voltage at the second resonant frequency enables the quadrupole rod filter to filter ions of a resolution exceeding a threshold m/z.
7. 7. The apparatus of claim 1, wherein the first resonant frequency is less than half of the second resonant frequency.
8. 8. The apparatus of claim 1, wherein the switching circuit is configured to switch the connection between the high frequency transformer assembly and the low frequency transformer assembly in less than 10 milliseconds.
9. 9. The apparatus of claim 1, wherein both the low frequency transformer assembly and the high frequency transformer assembly comprise an air core transformer.
10. 10. The apparatus of claim 1, wherein the low frequency transformer assembly comprises a split transformer having two halves, the apparatus further comprising a capacitor connected across the two halves of the low frequency transformer assembly.
11. 11. A dual frequency power supply system for driving multipole electrodes, the dual frequency power supply system comprising: An RF generator configured to selectively output an RF voltage at a first resonant frequency or at a second resonant frequency for driving the multipole rod electrode; a low frequency transformer assembly; high frequency transformer assembly, and A switching circuit configured to: Connecting the RF generator to the low frequency transformer assembly when the RF generator outputs the RF voltage at the first resonant frequency, the low frequency transformer assembly configured to supply a first voltage to an output coupled to the multipole rod electrode based on the RF voltage, Or connecting the RF generator to the high frequency transformer assembly when the RF generator outputs the RF voltage at the second resonant frequency, the high frequency transformer assembly configured to supply a second voltage to an output coupled to the multipole rod electrode based on the RF voltage.
12. 12. The system of claim 11, wherein the switching circuit comprises a first low pass network for filtering power at harmonics of the first resonant frequency and a second low pass network for filtering power at harmonics of the second resonant frequency.
13. 13. The system of claim 12, wherein the first low pass network and the second low pass network provide an impedance transformation between the RF generator and the output.
14. 14. The system of claim 11, further comprising a controller connected to the RF generator and the switching circuit and configured to selectively operate in a first mode or a second mode, wherein: In the first mode, the controller sets the RF generator to output the RF voltage at the first resonant frequency, sets the switching circuit to connect the RF generator and the low frequency transformer assembly, and sets the switching circuit to disconnect the RF generator from the high frequency transformer assembly, and In the second mode, the controller sets the RF generator to output the RF voltage at the second resonant frequency, sets the switching circuit to connect the RF generator and the high frequency transformer assembly, and sets the switching circuit to disconnect the RF generator from the low frequency transformer assembly.
15. 15. The system of claim 11, further comprising a quadrupole rod filter comprising the multipole electrode, and Wherein the first voltage at the first resonant frequency enables the quadrupole rod filter to filter ions in a first range of mass to charge ratios (m/z), and wherein the second voltage at the second resonant frequency enables the quadrupole rod filter to filter ions in a second range of m/z that is lower than the first range of m/z.
16. 16. The system of claim 11, further comprising a quadrupole rod filter comprising the multipole electrode, and Wherein the first voltage at the first resonant frequency enables the quadrupole rod filter to filter ions of a magnitude exceeding a threshold m/z, and wherein the second voltage at the second resonant frequency enables the quadrupole rod filter to filter ions of a resolution exceeding a threshold m/z.
17. 17. The system of claim 11, wherein the first resonant frequency is less than half of the second resonant frequency.
18. 18. The system of claim 11, wherein the switching circuit is configured to switch the connection between the high frequency transformer assembly and the low frequency transformer assembly in less than 10 milliseconds.
19. 19. The system of claim 11, wherein both the low frequency transformer assembly and the high frequency transformer assembly comprise an air core transformer.
20. 20. The system of claim 11, wherein the low frequency transformer assembly comprises a split transformer having two halves, the system further comprising a capacitor connected across the two halves of the low frequency transformer assembly.

Description

Dual-frequency power supply system for mass spectrometry RELATED APPLICATIONS The present application claims priority from U.S. provisional patent application No. 63/589,568 filed on 10/11 of 2023, the contents of which are hereby incorporated by reference in their entirety. Background Mass spectrometers can be used to detect, identify and/or quantify molecules based on the mass-to-charge ratio (m/z) of ions generated from the molecules. Mass spectrometers typically include an ion source for generating ions from molecules contained in a sample, a mass analyzer for separating ions based on their m/z, and an ion detector for detecting the separated ions. The mass spectrometer may include or be connected to a computer-based software platform that uses data from the ion detector to construct a mass spectrum that shows the relative abundance of each of the detected ions as a function of m/z. Mass spectra can be used to detect and quantify molecules in simple and complex mixtures. In some configurations, a separation system, such as a Liquid Chromatograph (LC), gas Chromatograph (GC), or Capillary Electrophoresis (CE) system, is coupled to a mass spectrometer in a combined system (e.g., LC-MS, GC-MS, or CE-MS system) to separate analytes in a sample prior to introducing the analytes to the mass spectrometer. One application of mass spectrometry is the identification, quantification and structural determination of peptides, proteins and related molecules in complex biological samples. In some such experiments, commonly referred to as multi-stage mass spectrometry (MSn, where n is 2 or greater) or tandem mass spectrometry (MS/MS or MS2 (n=2)), certain ions, referred to as precursor ions, are isolated and fragmented in a controlled manner to produce product ions. The product ions are then mass analyzed to generate a mass spectrum of the product ions. The mass spectrum of the product ions provides information that can be used to confirm the recognition result, determine the quantity, and/or derive structural details about the analyte of interest. Based on the difference in size of such molecules, mass spectrometers can filter for specific m/z ranges. However, due to the accuracy and magnitude of the input power characteristics utilized by the high performance components of the mass spectrometer, it may be difficult to configure the mass spectrometer to be able to filter for all practical m/z ranges. Disclosure of Invention The following description presents a simplified summary of one or more aspects of the methods and systems described herein in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects of the methods and systems described herein in a simplified form as a prelude to the more detailed description that is presented later. In some illustrative examples, an apparatus for performing mass spectrometry includes a set of multipole rod electrodes, an RF generator configured to selectively output an RF voltage at a first resonant frequency or at a second resonant frequency for driving the set of multipole rod electrodes, a low frequency transformer assembly, a high frequency transformer assembly, and a switching circuit configured to connect the RF generator to the low frequency transformer assembly when the RF generator outputs the RF voltage at the first resonant frequency, the low frequency transformer assembly configured to supply the first voltage to an output coupled to the set of multipole rod electrodes based on the RF voltage, or to connect the RF generator to the high frequency transformer assembly when the RF generator outputs the RF voltage at the second resonant frequency, the high frequency transformer assembly configured to supply the second voltage to an output coupled to the set of multipole rod electrodes based on the RF voltage. In some illustrative examples, a dual frequency power supply system for driving multipole rod electrodes includes an RF generator configured to selectively output an RF voltage at a first resonant frequency or at a second resonant frequency for driving the multipole rod electrodes, a low frequency transformer assembly, a high frequency transformer assembly, and a switching circuit configured to connect the RF generator to the low frequency transformer assembly when the RF generator outputs the RF voltage at the first resonant frequency, the low frequency transformer assembly configured to supply the first voltage to an output coupled to a set of multipole rod electrodes based on the RF voltage, or to connect the RF generator to the high frequency transformer assembly when the RF generator outputs the RF voltage at the second resonant frequency, the high frequency transformer assembly configured to supply the sec