Higher pressure ion source for two dimensional radio-frequency quadrupole electric field for mass spectrometer
US5942752A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 16, 1997 |
| Grant date | Aug 24, 1999 |
| Priority date | — |
| Expiry date | May 16, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J49/421
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention concerns an improved method and apparatus for analyzing and detecting a charge-neutral sample, which method comprises: PA1 (A) conveying a charge-neutral sample as a gas optionally in an inert carrier gas into a radio frequency-only quadrupole wherein said gas sample within said quadrupole is ionized into multiple ions which are focused and dampened by multiple collisions with the carrier gas or a damping gas toward the z-axis of said quadrupole at a pressure of between about 10.sup.-1 and about 10.sup.-4 torr; and PA1 (B) conveying the ionized focussed gas sample through a focusing element into a mass analyzing quadrupole mass spectrometer which is controlled by both radio frequency and DC; and PA1 (C) detecting and measuring the level of the multiple ions produced to create a mass spectrum. The present invention also relates to an improved method and apparatus for analyzing a charge-neutral sample, which method comprises: PA2 (a) obtaining a charge-neutral sample; PA2 (b) evaporating the sample in a gas chromatograph; PA2 (c) conveying the evaporated gas sample in an inert carrier gas into a radio-frequency-only quadrupole wherein said gas sample within said…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.