Systems and methods for conducting neutral loss scans in a single ion trap

Patent metadata

Field	Value
Publication number	US-10840074-B2
Application number	US-202016751265-A
Country	US
Kind code	B2
Filing date	Jan 24, 2020
Priority date	May 23, 2017
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

The invention generally relates to systems and methods for conducting neutral loss scans in a single ion trap. In certain aspects, the invention provides systems that include a mass spectrometer having a single ion trap, and a central processing unit (CPU), and storage coupled to the CPU for storing instructions that when executed by the CPU cause the system to apply a scan function that excites a precursor ion, rejects the precursor ion after its excitation, and ejects a product ion in the single ion trap.

First claim

What is claimed is:

1. A method of operating an ion trap, the method comprising: applying a scan function to a single ion trap that excites a precursor ion, rejects the precursor ion after its excitation, and ejects a product ion from the single ion trap.

2. The method according to claim 1 , wherein the scan function comprises three swept-frequency scans.

3. The method according to claim 2 , wherein the three swept-frequency scans are applied simultaneously to the single ion trap.

4. The method according to claim 3 , wherein each of the three swept-frequency scans is an inverse Mathieu q scan.

5. The method according to claim 4 , wherein a first frequency sweep excites the precursor ion.

6. The method according to claim 5 , wherein a second frequency sweep rejects the precursor ion after its excitation.

7. The method according to claim 6 , wherein a third frequency sweep ejects a product ion in the single ion trap.

8. The method according to claim 7 , wherein the second frequency sweep is between the first frequency sweep and the third frequency sweep.

9. The method according to claim 8 , wherein a constant mass offset is maintained between the first frequency sweep and the third frequency sweep.

10. The method according to claim 9 , wherein the first frequency sweep comprises a lower amplitude than either the second or third frequency sweeps.

11. A method for operating an ion trap, the method comprising: conducting a neutral loss scan in a single ion trap through simultaneous application of three swept-frequency scans to the single ion trap.

12. The method according to claim 11 , wherein each of the three swept-frequency scans is an inverse Mathieu q scan.

13. The method according to claim 12 , wherein a first frequency sweep excites a precursor ion in the single ion trap.

14. The method according to claim 13 , wherein a second frequency sweep rejects the precursor ion after its excitation.

15. The method according to claim 14 , wherein a third frequency sweep ejects a product ion in the single ion trap.

16. The method according to claim 15 , wherein the second frequency sweep is between the first frequency sweep and the third frequency sweep.

17. The method according to claim 16 , wherein a constant mass offset is maintained between the first frequency sweep and the third frequency sweep.

18. The method according to claim 17 , wherein the first frequency sweep comprises a lower amplitude than either the second or third frequency sweeps.

19. The method according to claim 18 , wherein the first and second frequency sweeps are applied in a y dimension.

20. The method according to claim 19 , wherein the third frequency sweep is applied in an x dimension and a detector of a mass spectrometer is also in the x dimension.

Assignees

• Purdue Research Foundation

Inventors

• Cooks Robert Graham
• Snyder Dalton

Classifications

• H01J49/0081 Primary

  Tandem in time, i.e. using a single spectrometer · CPC title

• H01J49/0036 Primary

  Step by step routines describing the handling of the data generated during a measurement · CPC title

• H01J49/429

  Scanning an electric parameter, e.g. voltage amplitude or frequency · CPC title

• H01J49/422

  Two-dimensional RF ion traps (ion guides without mass selection H01J49/062) · CPC title