The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 28, 2004
Filed:
Jan. 27, 2003
Jeffrey W. Finch, Mendon, MA (US);
Waters Investments Limited, New Castle, DE (US);
Abstract
Disclosed herein is a mass spectrometer having an atmospheric pressure photoionization (APPI) source that comprises a discharge lamp coupled to a nebulizer, wherein the nebulizer is at, or near, atmospheric pressure. The discharge lamp curves around the vapor path and this coaxial design offers significant advantages over the prior art such as increased photon flux resulting in increased photoionization efficiency. One of the significant benefits of an increase in photon flux is that absorption of the UV radiation by solvents such as acetonitrile is minimized. The APPI source described herein also facilitates a larger photoionization interaction zone with effluent from the nebulizer, which may be heated. Additionally, no dopant is required in this coaxial APPI system.