Pneumatically assisted electrospray device with alternating pressure gradients for mass spectrometry
US6207955A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 1998 |
| Grant date | Mar 27, 2001 |
| Priority date | — |
| Expiry date | Sep 28, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J49/045
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for producing gas-phase ions from a sample compound in a carrier liquid. The electrospray needle (or capillary) of the present invention includes a central metal tube which carries the liquid containing the sample compound. The central tube is surrounded by a plurality of tubes which transport a nebulizing gas. The nebulizing gas tubes are placed symmetrically around the outside of the liquid containing tube. The nebulizer of the present invention produces a symmetric, non-annular gas flow which has variations in pressure around the circumference of the central tube. The pressure variations of the nebulizing gas flow produce additional shear forces on the liquid emerging from the central tube. This assists in forming a uniform electrospray of droplets from the liquid at lower nebulizing gas flow rates, thereby reducing the disadvantageous effects of the higher gas flow rates used in the art. The symmetric arrangement of the nebulizing gas tubes provides support for the central sample carrying tube, thereby reducing the alignment problems found in prior art devices, and enhancing uniformity of the electrospray.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.