title: Evaluation of a commercial electro-kinetically pumped sheath-flow nanospray interface coupled to an automated capillary zone electrophoresis system.
abstract: Capillary zone electrophoresis-electrospray ionization-mass spectrometry (CZE-ESI-MS) is attracting renewed attention for proteomic and metabolomic analysis. An important reason for this interest is the maturation and commercialization of interfaces for coupling CZE with ESI-MS. One of these interfaces is an electro-kinetically pumped sheath flow nanospray interface developed by the Dovichi group, in which a very low sheath flow is generated based on electroosmosis within a glass emitter. CMP Scientific has commercialized this interface as the EMASS-II ion source. In this work, we compared the performance of the EMASS-II ion source with our in-house system. The performance of the systems is equivalent. We also coupled the EMASS-II ion source with a PrinCE Next|480 capillary electrophoresis autosampler and an Orbitrap mass spectrometer, and analyzed this system's performance in terms of sensitivity, reproducibility, and separation performance for separation of tryptic digests, intact proteins, and amino acids. The system produced reproducible analysis of BSA digest; the RSDs of peptide intensity and migration time across 24 runs were less than 20 and 6%, respectively. The system produced a linear calibration curve of intensity across a 30-fold range of tryptic digest concentration. The combination of a commercial autosampler and electrospray interface efficiently separated amino acids, peptides, and intact proteins, and only required 5 μL of sample for analysis. Graphical Abstract The commercial and locally constructed versions of the interface provide similar numbers of protein identifications from a Xenopus laevis fertilized egg digest.
authors.affiliation: Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA.
authors.forename: Elizabeth H
authors.initials: EH
authors.lastname: Peuchen
authors.affiliation: Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA.
authors.forename: Guije
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA.|Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA.
authors.forename: Liangliang
authors.initials: L
authors.lastname: Sun
authors.affiliation: Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA. ndovichi@nd.edu.
authors.forename: Norman J
authors.initials: NJ
authors.lastname: Dovichi
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001331:Automation; D002138:Calibration; D019075:Electrophoresis, Capillary / Q000379:methods*; D007700:Kinetics; D010455:Peptides / Q000737:chemistry; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D000596:Amino Acids; D010455:Peptides
keywords: Automated capillary zone electrophoresis-mass spectrometry; EMASS-II CE-MS interface; Electro-kinetically pumped sheath flow interface; Intact protein analysis; Proteomics