title: Improving mass spectrometer sensitivity using a high-pressure electrodynamic ion funnel interface.
abstract: We report on a new electrodynamic ion funnel that operates at a pressure of 30 torr with no loss of ion transmission. The enhanced performance compared with previous ion funnel designs optimized for pressures of <5 torr was achieved by reducing the ion funnel capacitance and increasing the RF drive frequency (1.7 MHz) and amplitude (100-170 V peak-to-peak). No degradation of ion transmission was observed for pressures from 2 to 30 torr. The ability to operate at higher pressure enabled a new tandem ion funnel mass spectrometer interface design that can accommodate a greater gas load (e.g., from an ESI source). When combined with a multicapillary inlet, the interface provided more efficient introduction of ions, resulting in a significant enhancement in mass spectrometer sensitivity and detection limits.
authors.affiliation: Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
authors.forename: Yehia
authors.initials: Y
authors.lastname: Ibrahim
authors.forename: Keqi
authors.initials: K
authors.lastname: Tang
authors.forename: Aleksey V
authors.initials: AV
authors.lastname: Tolmachev
authors.forename: Alexandre A
authors.initials: AA
authors.lastname: Shvartsburg
authors.forename: Richard D
authors.initials: RD
authors.lastname: Smith
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D011312:Pressure; D012212:Rheology / Q000295:instrumentation* / Q000379:methods; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation* / Q000379:methods; D014159:Transducers