Capillary-based multi nanoelectrospray emitters: improvements in ion transmission efficiency and implementation with capillary reversed-phase LC-ESI-MS.
We describe the coupling of liquid chromatography (LC) separations with mass spectrometry (MS) using nanoelectrospray ionization (nano-ESI) multiemitters. The array of 19 emitters reduced the flow rate delivered to each emitter, allowing the enhanced sensitivity that is characteristic of nano-ESI to be extended to higher flow rate separations. The signal for tryptic fragments from proteins spiked into a human plasma sample increased 11-fold on average when the multiemitters were employed, due to increased ionization efficiency and improved ion transfer efficiency through a newly designed heated multicapillary MS inlet. Additionally, the LC peak signal-to-noise ratio increased approximately 7-fold when the multiemitter configuration was used. The low dead volume of the emitter arrays preserved peak shape and resolution for robust capillary LC separations using total flow rates of 2 microL/min.
Biological Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, USA.
Ryan T
RT
Kelly
Jason S
JS
Page
Rui
R
Zhao
Wei-Jun
WJ
Qian
Heather M
HM
Mottaz
Keqi
K
Tang
Richard D
RD
Smith
D000595:Amino Acid Sequence; D000809:Angiotensins / Q000032:analysis; D000818:Animals; D002417:Cattle; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D007477:Ions / Q000737:chemistry; D008969:Molecular Sequence Data; D036103:Nanotechnology / Q000295:instrumentation*; D010455:Peptides / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods*
D000809:Angiotensins; D007477:Ions; D010455:Peptides