Author(s): Chris English
Restek Corporation
Published By: LCGC
Issue: Volume 18, Issue 06
Year of Publication: 2021
Abstract: Siloxane contamination can interfere with low-level analysis of target compounds whether they are discrete peaks or manifested as high background bleed. They are one of the most common types of “ghost peaks” in gas chromatography (GC) and can come from a variety of sources such as inlet septa, columns, valves, solvents, and vial cap seals. While both column bleed and other sources of contamination contain siloxanes, the composition is different. Examining the mass spectrum and structure provides clues to the source of the contamination. This article analyzes both septa bleed and column bleed fragments and reviews best practices in reducing siloxane “ghost peaks”, in addition to understanding the differences in composition.
