Improving mass spectrometer sensitivity using a high-pressure electrodynamic ion funnel interface.

Yehia Ibrahim; Keqi Tang; Aleksey V Tolmachev; Alexandre A Shvartsburg; Richard D Smith

doi:10.1016/j.jasms.2006.06.005

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Improving mass spectrometer sensitivity using a high-pressure electrodynamic ion funnel interface.

Yehia Ibrahim·Keqi Tang·Aleksey V Tolmachev·Alexandre A Shvartsburg·Richard D Smith

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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.

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Equipment Design Equipment Failure Analysis Pressure Rheology Sensitivity and Specificity Spectrometry, Mass, Electrospray Ionization Transducers Evaluation Study Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Yehia Ibrahim, Keqi Tang, Aleksey V Tolmachev, Alexandre A Shvartsburg, Richard D Smith. 2006-07-12. Improving mass spectrometer sensitivity using a high-pressure electrodynamic ion funnel interface.. https://doi.org/10.1016/j.jasms.2006.06.005

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