Systems for separating ions and neutrals and methods of operating the same

Patent metadata

Field	Value
Publication number	US-9558924-B2
Application number	US-201414564746-A
Country	US
Kind code	B2
Filing date	Dec 9, 2014
Priority date	Dec 9, 2014
Publication date	Jan 31, 2017
Grant date	Jan 31, 2017

Abstract

A mass spectrometer system includes a pulsed ion source configured to generate ionized molecules and neutral molecules. The system also includes a first enclosure coupled in flow communication with the pulsed ion source. The first enclosure defines a first vacuum chamber and an ion inlet aperture. The system further includes a detector positioned within said first enclosure and a plurality of ion transmission devices positioned within the first vacuum chamber and aligned with the ion inlet aperture. The plurality of ion transmission devices is configured to channel and accelerate ionized molecules through a first transmission path such that the ionized molecules and the neutral molecules are physically separated in space and temporally separated.

First claim

What is claimed is:

1. A mass spectrometer system comprising:
a pulsed ion source configured to generate ionized molecules and neutral molecules;
a first enclosure coupled in flow communication with said pulsed ion source, said first enclosure defining a first vacuum chamber;
a detector positioned within said first enclosure;
a second enclosure coupled to said first enclosure, wherein said first enclosure and said second enclosure define an ion inlet aperture and a neutral inlet aperture therebetween, said neutral inlet aperture separated a distance from said ion inlet aperture such that the ionized molecules and the neutral molecules are physically separated in space and temporally separated; and
a plurality of ion transmission devices positioned within said first vacuum chamber and aligned with said ion inlet aperture, said plurality of ion transmission devices configured to channel and accelerate ionized molecules through a first transmission path such that the ionized molecules and the neutral molecules are further physically separated in space and temporally separated.

2. The mass spectrometer system in accordance with claim 1 further comprising an ion guide aligned with said ion inlet aperture.

3. The mass spectrometer system in accordance with claim 2 , wherein said pulsed ion source further comprises an atmospheric pressure ionization (API) device and a valve aligned with said ion guide, said valve configured to inject ionized molecules into said ion guide as a plurality of pulses.

4. The mass spectrometer system in accordance with claim 3 , wherein said ion source further comprises an ion mobility spectrometry (IMS) device coupled to said API device and said valve.

5. The mass spectrometer system in accordance with claim 1 , said neutral inlet aperture configured to channel neutral molecules into said first enclosure from said second enclosure with a trajectory that facilitates extending the second transmission path such that the ionized molecules arrive at said detector prior to arrival of the neutral molecules.

6. The mass spectrometer system in accordance with claim 1 , wherein said first enclosure is coupled to a vacuum pump, said neutral inlet aperture is further configured to channel the neutral molecules into said first enclosure from said second enclosure such that a pressure in said second enclosure induced by the neutral molecules therein decays at a predetermined rate.

7. The mass spectrometer system in accordance with claim 1 , wherein said second enclosure defines a second vacuum chamber, wherein a pressure value of the second vacuum chamber is greater than a pressure value in the first vacuum chamber.

8. The mass spectrometer system in accordance with claim 1 , wherein said first enclosure is coupled to a first vacuum pump and said second enclosure is coupled to a second vacuum pump.

9. The mass spectrometer system in accordance with claim 1 , wherein said plurality of ion transmission devices comprises a plurality of multi-element ion optics configured to alter the direction of transmission of the ionized molecules, said plurality of ion transmission devices at least partially define said first transmission path.

10. The mass spectrometer system in accordance with claim 1 , wherein said plurality of ion transmission devices comprises a series of ion guides aligned with each other and aligned with said detector, said plurality of ion transmission devices at least partially define said first transmission path.

11. The mass spectrometer system in accordance with claim 1 , wherein said detector comprises a quadrupole mass analyzer.

12. The mass spectrometer system in accordance with claim 1 , wherein said detector comprises a time-of-flight mass analyzer.

13. A method of operating a mass spectrometer system, said method comprising:
channeling a pulsed sample into a first enclosure from a second enclosure coupled to the first enclosure through an ion inlet aperture, the sample including a plurality of ionized molecules and a first plurality of neutral molecules;
accelerating and channeling at least a portion of the ionized molecules through the first enclosure to a detector through a plurality of ion transmission devices aligned with the ion inlet aperture, the plurality of ion transmission devices define a first transmission path; and
channeling a second plurality of neutral molecules through a neutral inlet aperture defined between the first enclosure and the second enclosure, the neutral inlet aperture separated a distance from the ion inlet aperture such that the ionized molecules and the second plurality of neutral molecules are physically separated in space and temporally separated, the second plurality of neutral molecules channeled into the first enclosure through a second transmission path such that the ionized molecules and the second plurality of neutral molecules are further physically separated in space and temporally separated, wherein the ionized molecules arrive at the detector prior to arrival of the second plurality of neutral molecules.

14. The method in accordance with claim 13 , wherein accelerating and channeling the ionized molecules through the first enclosure to a detector through a first transmission path comprises altering the direction of the ionized molecules through a plurality of multi-element ion optics.

15. The method in accordance with claim 13 , wherein accelerating and channeling the ionized molecules through the first enclosure to a detector through a first transmission path comprises altering the direction of the ionized molecules through a series of ion guides aligned with each other and aligned with the detector.

16. The method in accordance with claim 13 , wherein accelerating and channeling the ionized molecules through the first enclosure to a detector through a first transmission path comprises subjecting the ionized molecules to electric fields configured to accelerate the ionized molecules in the first transmission path away from the second plurality of neutral molecules in the second transmission path.

17. The method in accordance with claim 13 , wherein channeling a pulsed sample into a first enclosure comprises injecting ionized molecules into an ion guide positioned within the second enclosure as a plurality of pulses.

18. The method in accordance with claim 17 , wherein injecting ionized molecules into an ion guide positioned within the second enclosure as a plurality of pulses comprises generating the ionized molecules with an atmospheric pressure ionization (API) device.

19. The method in accordance with claim 13 , wherein channeling the second plurality of neutral molecules through the first enclosure through the second transmission path comprises channeling the second plurality of neutral molecules into the second enclosure from the first enclosure such that a pressure in the second enclosure induced by the neutral molecules therein decays at a predetermined rate.

20. The method in accordance with claim 13 further comprising decreasing a first pressure in the first enclosure through a first vacuum pump and decreasing a second pressure in the second enclosure through a second vacuum pump, wherein the first pressure is greater than the second pressure.

Assignees

• Morpho Detection Llc

Inventors

• Syage Jack A

Classifications

• H01J49/0495 Primary

  Vacuum locks; Valves (valves per se F16K) · CPC title

• H01J49/162

  Direct photo-ionisation, e.g. single photon or multi-photon ionisation · CPC title

• H01J49/0031

  Step by step routines describing the use of the apparatus (H01J49/0081 takes precedence) · CPC title

• H01J49/0022

  Portable spectrometers, e.g. devices comprising independent power supply, constructional details relating to portability (small scale devices per se H01J49/0013 and H01J49/0018) · CPC title

• H01J49/24 Primary

  Vacuum systems, e.g. maintaining desired pressures · CPC title