HTC-15 - Abstract

Abstract Title: Can CE-MS improve the detection of peptides and intact proteins and in biological samples?
Abstract Type: Seminar
Session Choice: Challenges in Quantitative Analysis
Presenter Name: Dr Stephen Lock
Company/Organisation: Sciex
Country: United Kingdom

Abstract Information :

Capillary electrophoresis (CE) is an orthogonal technique to LC separating analytes based on their charge, and lends itself well to the analysis of peptides and proteins. The properties of CE enable the reduction and often elimination of carryover and wall absorption which effects peak resolution and sensitivity, as the CE capillary is not only the separation channel but also the autos-ampler and with no connections can be cleaned easily between analyses.

CE-MS especially techniques such as CESI (the integration of capillary electrophoresis (CE) and electrospray ionization (ESI) into a single process in a single device) are now enabling the easy connection of CE to a variety of mass spectrometers.

Some biologically important neuropeptides such as Vasoactive intestinal peptide (VIP) and Pituitary adenylate cyclase-activating polypeptide (PACAP) are very basic and are difficult to analyze by LC-MS methods as they bind to columns and have very poor chromatographic properties. In this work we will describe how a CESI-MS method was developed to detect intact neuropeptides of the size of PACAP (Molecular Weight of 4534.26 amu) and VIP in biological samples overcoming some of these challenges. The sensitivities from CESI-were compared with those from a high flow LC-MS method. We will discuss how sample preparation methods were developed to better enhance results after which the CE-MS method was tested on spiked samples to demonstrate how CE-MS can be used in bioanalysis. Finally we will discuss how CE-MS can then be used to quantitate even larger proteins.