Publication details
Capillary electrophoresis - Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry Using a vacuum deposition Interface
| Authors | |
|---|---|
| Year of publication | 2000 |
| Type | Article in Periodical |
| Magazine / Source | Analytical Chemistry |
| MU Faculty or unit | |
| Citation | |
| Field | Analytic chemistry |
| Keywords | MALDI; CE; interface; matrix-assisted laser desorption; vacuum; deposition; peptides; proteins; proteome; proteomic; digest |
| Description | An improved vacuum deposition interface for coupling capillary electrophoresis with MALDI/TOF MS has been developed. Liquid samples consisting of analyte and matrix were deposited on a moving tape in the evacuated source chamber of TOF mass spectrometer, enabling a day of continuous analysis without interruption. The vacuum deposition procedure was compared with the dried-droplet method, and it was found that vacuum deposition generated significantly more reproducible signal intensity, eliminating the need for the "sweet spot" searching. In addition, ion suppression caused by hydrophobicity differences in the analytes was reduced. In order to minimize ion suppression further, separation prior to MALDI/MS analysis was employed. The performance of capillary electrophoresis (CE) - MALDI/TOF MS using the vacuum deposition interface was evaluated with a peptide mixture injected at low femtomole levels. All peptides were baseline resolved with separation efficiencies in the range of 250,000 - 400,000 plates/m (2 - 3 second band halfwidth), demonstrating the high separation efficiency of the CE-MALDI/MS coupling. |