Ion funnel trap interface for orthogonal time-of-flight mass spectrometry.
A combined electrodynamic ion funnel and ion trap coupled to an orthogonal acceleration (oa)-time-of-flight mass spectrometer was developed and characterized. The ion trap was incorporated through the use of added terminal electrodynamic ion funnel electrodes enabling control over the axial dc gradient in the trap section. The ion trap operates efficiently at a pressure of approximately 1 Torr, and measurements indicate a maximum charge capacity of approximately 3 x 10(7) charges. An order of magnitude increase in sensitivity was observed in the analysis of low concentration peptides mixtures with orthogonal acceleration (oa)-time-of-flight mass spectrometry (oa-TOF MS) in the trapping mode as compared to the continuous regime. A signal increase in the trapping mode was accompanied by reduction in the chemical background, due to more efficient desolvation of, for example, solvent related clusters. Controlling the ion trap ejection time was found to result in efficient removal of singly charged species and improving signal-to-noise ratio (S/N) for the multiply charged analytes.
Ibrahim
Yehia
Y
Biological Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, USA.
Belov
Mikhail E
ME
Tolmachev
Aleksey V
AV
Prior
David C
DC
Smith
Richard D
RD
D001920:Bradykinin / Q000737:chemistry; D005344:Fibrinopeptide A / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013997:Time Factors
D007477:Ions; D005344:Fibrinopeptide A; D001920:Bradykinin