Automated gain control ion funnel trap for orthogonal time-of-flight mass spectrometry.
Time-of-flight mass spectrometry (TOF MS) is increasingly used in proteomics research. Herein, we report on the development and characterization of a TOF MS instrument with improved sensitivity equipped with an electrodynamic ion funnel trap (IFT) that employs an automated gain control (AGC) capability. The IFT-TOF MS was coupled to a reversed-phase capillary liquid chromatography (RPLC) separation and evaluated in experiments with complex proteolytic digests. When applied to a global tryptic digest of Shewanella oneidensis proteins, an order-of-magnitude increase in sensitivity compared to that of the conventional continuous mode of operation was achieved due to efficient ion accumulation prior to TOF MS analysis. As a result of this sensitivity improvement and related improvement in mass measurement accuracy, the number of unique peptides identified in the AGC-IFT mode was 5-fold greater than that obtained in the continuous mode.
Biological Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, USA.
Yehia M
YM
Ibrahim
Mikhail E
ME
Belov
Andrei V
AV
Liyu
Richard D
RD
Smith
D001331:Automation; D007477:Ions / Q000737:chemistry; D013058:Mass Spectrometry / Q000295:instrumentation* / Q000379:methods*; D010455:Peptides / Q000737:chemistry; D013997:Time Factors
D007477:Ions; D010455:Peptides