Mass spectrometry device and ion detection method therefor

• US 10,453,663 B2
• Filed: 01/21/2016
• Issued: 10/22/2019
• Est. Priority Date: 01/21/2016
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: Murakami, Shinichi, Terui, Yasushi
• Primary Examiner(s): Maskell, Michael
• Application Number:
  US16/069,066
• Publication Number:
  US 20190027350A1
• Time in Patent Office: 1,370 Days
• Field of Search: 250281, 250282, 250288
• CPC Class Codes: H01J 49/0009 Calibration of the apparatus
• CPC Class Codes: H01J 49/0036 Step by step routines describing the handling of the data generated during a measurement
• CPC Class Codes: H01J 49/025 Detectors specially adapted to particle spectrometers data acquisition H01J49/0036; detectors per se G01T, e.g. G01T1/28, G01T1/29
• CPC Class Codes: H01J 49/4215 Quadrupole mass filters H01J49/4225 takes precedence

Abstract

An object of the invention is to provide a mass spectrometry device and an ion detection method therefor in which an ion amount can be detected with high accuracy.

In order to achieve the object described above, a mass spectrometry device is provided which performs a channel scan measurement by changing a voltage to be applied to a mass separation unit to selectively extract a desired ion. The mass spectrometry device includes: an ion detection unit which detects an ion separated by the mass separation unit and outputs an electric signal; an ion amount measuring unit which measures an ion amount from the output of the ion detection unit; and an ion amount correction unit which corrects a detection amount of ion from an output of the ion amount measuring unit. In a process of a channel scan, the ion amount correction unit performs correction of a detection amount of ion detected in a present channel based on a detection amount of ion in a previous channel.

Claims

1. A mass spectrometry device which performs a channel scan measurement by changing a voltage to be applied to a mass separation unit to selectively extract a desired ion, the device comprising:

an ion detection unit which detects an ion separated by the mass separation unit and outputs an electric signal;

an ion amount measuring unit which measures an ion amount from the output of the ion detection unit; and

an ion amount correction unit which corrects a detection amount of ion from an output of the ion amount measuring unit, wherein

in a process of a channel scan, the ion amount correction unit performs correction of a detection amount of ion detected in a present channel based on a detection amount of ion in a previous channel, and

in the ion amount correction unit, an ion correction amount of the present channel is decided based on the detection amount of ion in the previous channel a measurement time of one channel, and an interval time required for a channel switch.

2. The mass spectrometry device according to claim 1, further comprising:

a correction information calculation unit which, for a plurality of measurement samples having different concentrations, measures an attenuation process of the detection amount of ion when ions are blocked and calculates the correction amount in association with the detection amount of ion before the ion blocking.

3. The mass spectrometry device according to claim 2, wherein

the correction information calculation unit approximates a relation between the detection amount of ion before the ion blocking and the correction amount by an expression, and

the device further includes a correction information storage unit which stores information of the derived approximate expression.

4. The mass spectrometry device according to claim 2, wherein

the mass separation unit is a quadrupole mass filter, and

the ion blocking is realized by controlling a voltage to be applied to the quadrupole mass filter.

5. The mass spectrometry device according to claim 1, wherein

the ion detection unit includes a scintillator.

6. The mass spectrometry device according to claim 1,

wherein said mass spectrometry device is configured to perform a channel scan measurement by measuring an ion extracted by a mass separation, and

wherein the mass spectroscopy device further comprises a set value input screen for selecting a measurement time of one channel and an interval time.

7. The mass spectrometry device according to claim 1, further comprising:

an input setting screen for selecting whether to apply a correction processing which corrects the detection amount of the ion extracted by the mass separation in the process of the channel scan.

8. The mass spectrometry device according to claim 1, further comprising:

a display screen which displays a relation between the detection amount of ion and a correction value after the correction processing which corrects the detection amount of the ion extracted by the mass separation in the process of the channel scan.

9. A mass spectrometry device which performs a channel scan measurement by changing a voltage to be applied to a mass separation unit to selectively extract a desired ion, the device comprising:

an ion detection unit which detects an ion separated by the mass separation unit and outputs an electric signal;

an ion amount measuring unit which measures an ion amount from the output of the ion detection unit;

an ion amount correction unit which corrects a detection amount of ion from an output of the ion amount measuring unit; and

a correction information calculation unit which, for a plurality of measurement samples having different concentrations, measures an attenuation process of the detection amount of ion when ions are blocked and calculates the correction amount in association with the detection amount of ion before the ion blocking, wherein

in a process of a channel scan, the ion amount correction unit performs correction of a detection amount of ion detected in a present channel based on a detection amount of ion in a previous channel,

the correction information calculation unit approximates a relation between the detection amount of ion before the ion blocking and the correction amount by an expression, and

the device further includes a correction information storage unit which stores information of the derived approximate expression.

10. The mass spectrometry device according to claim 9, wherein

in the ion amount correction unit, an ion correction amount of the present channel is decided based on the detection amount of ion in the previous channel, a measurement time of one channel, and an interval time required for a channel switch.

11. The mass spectrometry device according to claim 9, wherein

the mass separation unit is a quadrupole mass filter, and

the ion blocking is realized by controlling a voltage to be applied to the quadrupole mass filter.

12. The mass spectrometry device according to claim 9, wherein

the ion detection unit includes a scintillator.

13. The mass spectrometry device according to claim 9,

wherein said mass spectrometry device is configured to perform a channel scan measurement by measuring an ion extracted by a mass separation, and

wherein the mass spectroscopy device further comprises a set value input screen for selecting a measurement time of one channel and an interval time.

14. The mass spectrometry device according to claim 9, further comprising:

an input setting screen for selecting whether to apply a correction processing which corrects the detection amount of the ion extracted by the mass separation in the process of the channel scan.

15. The mass spectrometry device according to claim 9, further comprising:

a display screen which displays a relation between the detection amount of ion and a correction value after the correction processing which corrects the detection amount of the ion extracted by the mass separation in the process of the channel scan.