Chromatography Forum

Hello!
Anyone experienced in determining ethylene oxide residuals in medical devices after sterilization - ISO 10993-7?

We need to analyze ethylene oxide and 2-chloroethanol (ethylene chlorohydrin).
Temperature of boiling point at atmospheric pressure for 2-chloroethanol is 128,6 °C
Our solvent is water.
Our carrier gas is He.

We have problems separating the peaks (water + 2-chloroethanol).
Which temperature we should select for injection?
We tried a lot of variations of the split, injection temperature, oven temperature.

Thanks,
Catarina Rocha

Ms. Rocha,

GC is about separations and in GC that means it is about the column. The more information you provide about the column and conditions, the more likely you are get tips about a solution.

You mention water as the solvent so I have to ask what detector you are using and what injection volume and split.

Best regards,

AICMM

AICMM,

GC - 456 SCION, FID Detector.
Injector: split/ splitless

We change our column to DB-SELECT 624 UI 30m, 0.53mm, 3µm, because we had problems with our last column (SCION-WAXMS 60m, 0.32mm, 1µm).

The best results we obtained were analyzed with the following conditions:
Carrier gas: He
Split: 1:5
Injection temperature: 180ºC
Injection volume: 1uL

Oven:
100ºC for 1 minute and increasing 2ºC/min to 145ºC then hold 1 min.
Constant flow: 2ml/min

Please see our chromatogram:


Thanks,
Catarina Rocha

Perhaps this could be helpful to you?

https://www.chromatographyonline.com/vi ... -solutions

Depending on the complexity of your matrix, a good old flame detector might be the best option. When I searched for 2-chloroethanol in the Restek chromatogram database, the result indicated was that the mass spectrometer might not be the best detector for 2-chloroethanol.

www.restek.com - then look under Resources and Education, search the GC chromatogram database by analyte.