There is described an interface for delivering ions generated in an ion
source into a mass analyzer in a chamber under vacuum pressure. In
particular, the interface employs two consecutive ion guides operated to
dissociate adduct ions formed in the ion source or high pressure regions
of the interface between the ion source and the mass analyzer, thus
improving the limit of detection or limit of quantitation of the mass
analyzer by increasing the analyte ion current.The questions raised in
reexamination request no. 90/007,724, filed Sep. 16, 2005 have been
considered and the results thereof are reflected in this reissue patent
which constitutes the reexamination certificate required by 35 U.S.C. 307
as provided in 37 CFR 1.570(e), for ex parte reexaminations, or the
reexamination certificate required by 35 U.S.C. 316 as provided in 37 CFR
1.997(e) for inter partes reexaminations.