Date of Graduation
Eberly College of Arts and Sciences
Lisa A. Holland
Stephen J. Valentine
Capillary electrophoresis-mass spectrometry is a powerful technique for high-throughput and high efficiency separations combined with structural identification. Electrospray ionization is the primary interface used to couple capillary electrophoresis to mass analyzers; however, improved designs continue to be reported. A new interfacing method based on vibrating sharp-edge spray ionization is presented in this work to overcome the challenges of decoupling applied voltages and to enhance the compatibility with separations performed at near-neutral pH. The versatility and ease of use of this ionization source is demonstrated using β-blockers, peptides, and proteins. The cationic β-blocker pindolol was injected electrokinetically and detected at concentrations ranging from 10 nM to 5 μM, with an estimated detection limit of 2 nM. The vibrating sharp-edge spray ionization functions with flow rates from 70 to 200 nL/min and did not perturb the capillary electrophoresis separation electroosmotic flow as evidenced by the observation that most migration times differed less than 7% (n = 3) across a lab-built system interfaced to mass spectrometry and a commercial system that utilizes absorbance detection. For cationic βblockers the theoretical plates achieved in the capillary electrophoresis-mass spectrometry setup were 80% to 95% of that observed with a commercial capillary electrophoresis-UV absorbance detection system.
Kristoff, Courtney J., "Development and implementation of a novel voltage-free interface for capillary electrophoresis-mass spectrometry separations of proteins" (2020). Graduate Theses, Dissertations, and Problem Reports. 7853.
Available for download on Friday, December 03, 2021