Ion Transfer Arrangement with Spatially Alternating DC and Viscous Ion Flow

• US 20100038533A1
• Filed: 11/07/2007
• Published: 02/18/2010
• Est. Priority Date: 11/07/2006
• Status: Active Grant

• Current Assignee: Thermo Fisher Scientific GmbH (Thermo Fisher Scientific Incorporated)
• Original Assignee: Thermo Fisher Scientific GmbH (Thermo Fisher Scientific Incorporated)
• Inventors: Malek, Robert, Makarov, Alexander A., Pesch, Reinhold, Kozlovskiy, Viacheslav
• Granted Patent: US 8,148,680 B2
• Time in Patent Office: Days
• US Class Current: 250/288
• CPC Class Codes: H01J 3/14 Arrangements for focusing or reflecting ray or beam H01J3/02, H01J3/04 take precedence
• CPC Class Codes: H01J 49/062 Ion guides linear ion traps performing mass selection H01J49/4225, mass filters H01J49/421

Abstract

A method of transporting gas and entrained ions between higher and lower pressure regions of a mass spectrometer comprises providing an ion transfer conduit 60 between the higher and lower pressure regions. The ion transfer conduit 60 includes an electrode assembly 300 which defines an ion transfer channel. The electrode assembly 300 has a first set of ring electrodes 305 of a first width D1, and a second set of ring electrodes of a second width D2 (≧D1) and interleaved with the first ring electrodes 305. A DC voltage of magnitude V₁ and a first polarity is supplied to the first ring electrodes 205 and a DC voltage of magnitude V₂ which may be less than or equal to the magnitude of V₁ but with an opposed polarity is applied to the second ring electrodes 310. The pressure of the ion transfer conduit 60 is controlled so as to maintain viscous flow of gas and ions within the ion transfer channel.

Claims

1. An ion transfer arrangement for transporting ions between a relatively high pressure region and a relatively low pressure region, comprising:

an ion transfer conduit having an inlet opening towards a relatively high pressure chamber, an outlet opening towards a relatively low pressure chamber, and at least one sidewall surrounding an ion transfer channel, the sidewall extending along a central axis between the inlet end and the outlet end; and

a plurality of apertures formed in the longitudinal direction of the sidewall so as to permit a flow of gas from within the ion transfer channel to a lower pressure region outside of the sidewall of the conduit.

2-26. -26. (canceled)