Parts per million mass accuracy on an Orbitrap mass spectrometer via lock mass injection into a C-trap
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Parts per million mass accuracy on an Orbitrap mass spectrometer via lock mass injection into a C-trap. / Olsen, Jesper Velgaard; de Godoy, Lyris M F; Li, Guoqing; Macek, Boris; Mortensen, Peter; Pesch, Reinhold; Makarov, Alexander; Lange, Oliver; Horning, Stevan; Mann, Matthias.
In: Molecular and Cellular Proteomics, Vol. 4, No. 12, 2005, p. 2010-21.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Parts per million mass accuracy on an Orbitrap mass spectrometer via lock mass injection into a C-trap
AU - Olsen, Jesper Velgaard
AU - de Godoy, Lyris M F
AU - Li, Guoqing
AU - Macek, Boris
AU - Mortensen, Peter
AU - Pesch, Reinhold
AU - Makarov, Alexander
AU - Lange, Oliver
AU - Horning, Stevan
AU - Mann, Matthias
N1 - Keywords: Freeze Drying; Mass Spectrometry; Peptide Fragments; Reproducibility of Results; Sensitivity and Specificity; Serum Albumin, Bovine
PY - 2005
Y1 - 2005
N2 - Mass accuracy is a key parameter of mass spectrometric performance. TOF instruments can reach low parts per million, and FT-ICR instruments are capable of even greater accuracy provided ion numbers are well controlled. Here we demonstrate sub-ppm mass accuracy on a linear ion trap coupled via a radio frequency-only storage trap (C-trap) to the orbitrap mass spectrometer (LTQ Orbitrap). Prior to acquisition of a spectrum, a background ion originating from ambient air is first transferred to the C-trap. Ions forming the MS or MS(n) spectrum are then added to this species, and all ions are injected into the orbitrap for analysis. Real time recalibration on the "lock mass" by corrections of mass shift removes mass error associated with calibration of the mass scale. The remaining mass error is mainly due to imperfect peaks caused by weak signals and is addressed by averaging the mass measurement over the LC peak, weighted by signal intensity. For peptide database searches in proteomics, we introduce a variable mass tolerance and achieve average absolute mass deviations of 0.48 ppm (standard deviation 0.38 ppm) and maximal deviations of less than 2 ppm. For tandem mass spectra we demonstrate similarly high mass accuracy and discuss its impact on database searching. High and routine mass accuracy in a compact instrument will dramatically improve certainty of peptide and small molecule identification.
AB - Mass accuracy is a key parameter of mass spectrometric performance. TOF instruments can reach low parts per million, and FT-ICR instruments are capable of even greater accuracy provided ion numbers are well controlled. Here we demonstrate sub-ppm mass accuracy on a linear ion trap coupled via a radio frequency-only storage trap (C-trap) to the orbitrap mass spectrometer (LTQ Orbitrap). Prior to acquisition of a spectrum, a background ion originating from ambient air is first transferred to the C-trap. Ions forming the MS or MS(n) spectrum are then added to this species, and all ions are injected into the orbitrap for analysis. Real time recalibration on the "lock mass" by corrections of mass shift removes mass error associated with calibration of the mass scale. The remaining mass error is mainly due to imperfect peaks caused by weak signals and is addressed by averaging the mass measurement over the LC peak, weighted by signal intensity. For peptide database searches in proteomics, we introduce a variable mass tolerance and achieve average absolute mass deviations of 0.48 ppm (standard deviation 0.38 ppm) and maximal deviations of less than 2 ppm. For tandem mass spectra we demonstrate similarly high mass accuracy and discuss its impact on database searching. High and routine mass accuracy in a compact instrument will dramatically improve certainty of peptide and small molecule identification.
U2 - 10.1074/mcp.T500030-MCP200
DO - 10.1074/mcp.T500030-MCP200
M3 - Journal article
C2 - 16249172
VL - 4
SP - 2010
EP - 2021
JO - Molecular and Cellular Proteomics
JF - Molecular and Cellular Proteomics
SN - 1535-9476
IS - 12
ER -
ID: 46458834