Stable reproducible and automated capillary zone electrophoresis-tandem mass spectrometry system with an electrokinetically pumped sheath-flow nanospray interface

摘要

A PrinCE autosampler was coupled to a Q-Exactive mass spectrometer by an electrokinetically pumped sheath-flow nanospray interface to perform automated capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS). 20 ng aliquots of an E. coli digest were injected to evaluate the system. Eight sequential injections over an eight-hour period identified 1,115 ± 70 (relative standard deviation, RSD = 6%) peptides and 270 ± 8 (RSD = 3%) proteins per run. The average RSDs of migration time, peak intensity, and peak area were 3%, 24% and 19% respectively, for 340 peptides with high intensity. This is the first report of an automated CZE-ESI-MS/MS system using the electrokinetically pumped sheath-flow nanospray interface. The results demonstrate that this system is capable of reproducibly identifying over 1,000 peptides from an E.coli tryptic digest in a one-hour analysis time.