Can You Use a Polyethylene Glycol (PEG) Phase for GC–MS?

Practical GC in gas chromatography: learn how PEG column bleed affects MS sensitivity, and when polar analytes still quantify reliably.

One of the most common stationary phases for gas chromatography (GC) is the polyethylene glycol (PEG) or “wax” columns. They are highly polar when compared to polydimethylsiloxane (PDMS) phases, such as a 5-type column
(5% diphenyl/95% dimethyl polysiloxane). The carbon-carbon–oxygen backbone is highly selective for alcohols, glycols, aldehydes, and ethers, offering unique selectivity unavailable in other phases. While many analysts avoid using a mass spectrometer (MS) with a PEG phase, this article will explore the differences in sensitivity, selectivity, reproducibility,
and bleed compared with a traditional PDMS-based column.