| 摘要 |
<p>A mass spectrometer is disclosed wherein highly charged fragment ions resulting from the fragmentation of multiply charged parent ions are reduced in charge state within a Proton Transfer Reaction (PTR) cell 35 by reacting the fragment ions with one or more neutral reagent gases. The non-ionic reagent gas may be an uncharged superbase reagent gas or vapour, such as Octahydropyrimidolazepine or Tetramethylguanidine, or a volatile amine, such as trimethyl-amine or triethyl-amine. The parent ions may be fragmented within an Electron Transfer Dissociation (ETD) cell 33 by reacting the parent ions with at least one neutral reagent gas or vapour, e.g. an uncharged alkali metal vapour such as caesium vapor. Both the ETD cell 33 and the PTR cell may be formed from a RF ion guide comprising a plurality of stacked ring electrodes, each electrode having an aperture through which ions are transmitted in use.</p> |
