In this work the Subambient Pressure Ionization with Nanoelectrospray (SPIN) ion source and interface which operates at ~15-30 Torr is demonstrated to be compatible with gradient reversed-phase liquid chromatography-MS applications, exemplified here with the analysis of complex samples (a protein tryptic digest and a whole cell lysate). A low liquid chromatographic flow rate (100-400 nL/min) allowed stable electrospray to be established while avoiding electrical breakdown. Efforts to increase the operating pressure of the SPIN source relative to previously reported designs prevented solvent freezing and enhanced charged cluster/droplet desolvation. A 5-12-fold improvement in sensitivity relative to a conventional atmospheric pressure nanoelectrospray ionization (ESI) source was obtained for detected peptides.
Revised: July 26, 2011 |
Published: April 22, 2011
Citation
Tang K., J.S. Page, I. Marginean, R.T. Kelly, and R.D. Smith. 2011.Improving liquid chromatography-mass spectrometry sensitivity using a subambient pressure ionization with nanoelectrospray (SPIN) interface.Journal of the American Society for Mass Spectrometry 22, no. 8:1318-1325.PNNL-SA-77025.doi:10.1007/s13361-011-0135-7