Glycols.... Tis The Season!

Tis the season to be thinking about glycols…. Why you ask?  Well its currently winter as I’m writing this and glycols, specifically propylene glycol (PG) and ethylene glycol (EG), along with other ingredients, are used in airports for deicing planes.  Propylene glycol based fluids are more common since they are less toxic than ethylene glycol fluids.

Glycols are highly soluble in water and are readily transported to waterways. While these compounds can be quickly degraded by bacteria, this process can use up available oxygen killing animals that rely on oxygen in the water to survive. Due to these effects on the surface waters and marine habitats, it’s crucial to get precise and accurate data, ensuring the analysis of these samples to maintain healthy and habitable waters.

If you’re having trouble with your aqueous glycol injections, as in; symmetrical peak shapes, consistent retention and robust methods, give these helpful tips a try to see if they help your analysis.

• Rtx-Wax column (cat# 12455)
• Sky Precision Liner with wool (cat# 23305)
• 1 µL injection volume with 50:1 split
• 50:50 water/methanol rinse

Because split injection was used for the analysis of glycols in water, it provides rapid sample transfer and a narrow analyte band, which produces symmetrical peaks, retention time consistency, and also improves reproducibility for low-level analysis of glycols in water. In addition, it reduces the amount of water in the injection port, which minimizes the potential for backflash. The 50:1 split injection used in this method effectively prevented sample expansion volume issues. Even though the amount of sample on column was significantly reduced, adequate sensitivity and linearity were still achieved.

Figure 1: Shows propylene and ethylene glycols at 1 ng on column concentration in 50:1 split mode.

References:

Restek - Reliable Low-Level Analysis of Glycols in Water Using Split Injection