Data acquisition method in a mass spectrometer

Patent metadata

Field	Value
Publication number	US-11031218-B2
Application number	US-201816645863-A
Country	US
Kind code	B2
Filing date	Oct 29, 2018
Priority date	Nov 23, 2017
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

A data acquisition method in a mass spectrometer includes a. providing an ion source to generate precursor ions; b. feeding the precursor ions into a first mass analyzer that selects one mass window such that the precursor ions located outside the mass window pass through the first mass analyzer and the precursor ions located within the mass window cannot pass through the first mass analyzer; c. feeding the precursor ions passing through the first mass analyzer into a collision cell for collisional dissociation, to generate product ions; d. feeding the product ions into a second mass analyzer for mass analysis and recording a spectrum; and e. repeating Steps b-d. Each time when Step b is repeatedly performed, the selected mass window does not overlap with all the mass windows previously selected. After all the mass windows in a mass range are selected, the repetition is stopped.

First claim

The invention claimed is:

1. A data acquisition method in a mass spectrometer, comprising:
a. providing an ion source to generate precursor ions;
b. feeding the precursor ions into a first mass analyzer, wherein the first mass analyzer selects at least one mass window such that the precursor ions located outside the mass window pass through the first mass analyzer and the precursor ions located within the mass window cannot pass through the first mass analyzer;
c. feeding the precursor ions passing through the first mass analyzer into a collision cell for collisional dissociation, to generate product ions;
d. feeding the product ions into a second mass analyzer for mass analysis and recording a spectrum; and
e. repeating Steps b to d, wherein each time when Step b is repeatedly performed, the selected mass window does not overlap with all the mass windows previously selected; and after all the mass windows in a mass range have been selected, the repetition is stopped.

2. The data acquisition method according to claim 1 , comprising Step f, which is after Step e, wherein
the Step f comprises obtaining a spectrum corresponding to the product ions generated by the precursor ions in said selected mass window by a first time data post-processing.

3. The data acquisition method according to claim 2 , comprising Step g or Step j, which are after Step f, wherein
the Step g comprises obtaining a spectrum corresponding to the product ions generated by the precursor ions in said selected mass windows by second mathematical post-processing; and
the Step j comprises comparing the spectrum of the product ions with a database, and identifying an analyte.

4. The data acquisition method according to claim 3 , comprising Step h, which is after Step e, wherein
the Step h comprises obtaining a summed spectrum by summing all said recorded spectra.

5. The data acquisition method according to claim 4 , wherein when Step g is comprised after Step f, Step i is included after Step h; and when Step j is included after Step f, Step i′ is included after Step h, wherein
the Step i comprises taking said spectrum obtained in Step g as a qualitative result, and said summed spectrum obtained in Step h as a quantitative result; and
the Step i′ comprises performing a quantitative analysis based on the result obtained in Step j in combination with said summed spectrum obtained in Step h.

6. The data acquisition method according to claim 5 , comprising, after Step a, performing Step k at least once, wherein
the Step k comprises allowing all the ions in said mass range pass through the first mass analyzer and enter the collision cell for disassociation, and feeding all the disassociated product ions into the second mass analyzer for mass analysis and recording a spectrum.

7. The data acquisition method according to claim 6 , wherein said mass spectrum obtained in Step k is used as one of the data sources in Step f, to correct a calculation error in Step f.

8. The data acquisition method according to claim 3 , comprising a step of chromatographic separation for the analyte before Step a.

9. The data acquisition method according to claim 8 , wherein the second time data post-processing in Step g comprises performing deconvolution to correlate the precursor ions and product ions of the same analyte, according to the consistency in chromatographic peak profile or retention time between the precursor ions and product ions.

10. The data acquisition method according to claim 2 , wherein the spectrum is subjected to noise reduction processing before Step f.

11. The data acquisition method according to claim 10 , wherein the noise reduction processing comprises removing high-frequency noises by Fast Fourier Transform algorithm.

12. The data acquisition method according to claim 2 , wherein in Step f, an inverse Hadamard transform algorism is used in the first time data post-processing.

13. The data acquisition method according to claim 1 , comprising a precursor ion scan before Step b, and said scan is implemented by the second mass analyzer.

14. The data acquisition method according to claim 1 , wherein the first mass analyzer is a quadrupole mass analyzer, an ion trap mass analyzer, or a time-of-flight mass analyzer.

15. The data acquisition method according to claim 1 , wherein the second mass analyzer is a time-of-flight mass analyzer or a Fourier transform-type mass analyzer.

16. The data acquisition method according to claim 1 , comprising a step of separating the precursor ions according to the ion mobility before Step b.

17. The data acquisition method according to claim 1 , wherein the ions in said mass window which do not pass through the first mass analyzer are ejected along a certain direction of the first mass analyzer for the following analysis or detection.

18. The data acquisition method according to claim 1 , wherein in Step b, a mass window is selected in the first mass analyzer, which comprising at least 5 mass units (Dalton) in a consecutive manner.

19. The data acquisition method according to claim 1 , wherein in Step b, at least 5 non-continuous mass windows are selected in the first mass analyzer, wherein each window comprising 1 mass unit (Dalton).

20. The data acquisition method according to claim 19 , wherein said at least 5 non-continuous mass windows have a pseudo-random distribution.

Assignees

• Shimadzu Corp

Inventors

• Zhang Xiaoqiang
• Huang Yunqing
• Sun Wenjian

Classifications

• H01J49/0036 Primary

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

• H01J49/0045

  characterised by the fragmentation or other specific reaction · CPC title

• H01J49/429

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

• H01J49/0027 Primary

  Methods for using particle spectrometers · CPC title

• H01J49/427

  Ejection and selection methods · CPC title