Czech Society for Mass Spectrometry

(4th Conference of the Czech Society for Mass Spectrometry - PL-2)
Direct determination of intact proteins using liquid chromatography and multiple reaction monitoring on a triple quadrupole mass spectrometer

Kevin A. Schug ^1 *

1. The University of Texas at Arlington

Abstract

Proteins are essential to life. In recent years, changes in abundances of different proteins have been linked to various disease states as biomarkers. Further, protein therapeutics are becoming increasingly used for treatment of diseases. In both of these cases, efficient and effective methods for protein quantitation from complex biological matrices are desired [1]. Traditionally, protein quantitation has involved protein digestion and determination based on levels of peptide products. Our group has been working to accomplish direct separation and mass spectrometric determination of intact proteins. This has some inherent challenges, including the complexity of the analyte and the low resolution of the triple quadrupole instrument used for multiple reaction monitoring. Even so, with the tuning of some key variables, including collision gas pressure and collision energy, reproducible and intense characteristic fragments for candidate intact protein analytes can be obtained [2]. When coupled with high efficiency separations on next generation stationary phases and on-line sample preparation, the potential for direct quantitation of protein analytes without digestion becomes tractable. This talk will describe the work we have done to date and the questions that still remain unanswered with respect to making such a work-flow common place in the analytical laboratory.

* Corresponding author: kschug@uta.edu

References

1. Makawita, S. et al.: Clin. Chem. 56, 2212-2222 (2010).
2. Wang, E.H. et al.: submitted for publication (2015).