Patent · US Active

Ambient pressure pyroelectric ion source for mass spectrometry

US7791019B2 · kind B2 · utility

3Cited by
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20Claims
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Key dates

Filing dateJan 11, 2008
Grant dateSep 7, 2010
Priority date
Expiry dateMar 4, 2029

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J49/0459
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A compact, low power ambient pressure pyroelectric ionization source. The source can be constructed using a z-cut lithium niobate or lithium tantalate crystal with an attached resistive heater mounted in front of the atmospheric pressure inlet of an ion trap mass spectrometer. Positive and negative ion formation alternately results from thermally cycling the crystal over a narrow temperature range. Ionization of molecules such as 1,1,1,3,3,3-hexafluoroisopropanol or benzoic acid results in the observation of the singly deprotonated species and their clusters in the negative ion mass spectrum. Ionization of molecules such as triethylamine or triphenylamine with the source results in observation of the corresponding singly protonated species of each in the positive ion mass spectrum. The pyroelectric crystals are thermally cycled by as little as 30 K from ambient temperature. Ion formation is largely unaffected by contamination of the crystal faces. This ion source is robust.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.