Chromatography Forum

Hello, I am another new bird on GC in this forum. Now I am trying to develop a GC method to seperate two diastereomers of alcohol. MW is about 100. They prefer to use regular GC column instead of chiral GC column. I think it is possible to use regular column because diastereomers are quite different in properties not like enantiomers. But I completely no idea how to select GC column. Anybody has any suggestions where to start with? Thank you so much.

Low MW Underivitized alcohols elute with symmetry and efficiency on only a few phases, the best are probably PEG type phases.

PDMS phase columns may work for you. Probably the better solution in any case is to have as much separating efficiency as possible, IE thin film and as small a diameter of capillary column as possible.

Good luck,

Rodney George
consultant

mibobdog,

You might take a look at the blood alcohol columns from Restek and J&W.

Best regards.

We use either PEG and 624 type capillaries for lower alcohols. 624 is used in USP 611.

You'll find many of the major supplier have selection guides.

Phenomenex also do a column selection by manufacturer in their catalog.

We use a ZB-624 for separating methanol, ethanol and IPA almost everyday.
30m x 0.53, DF 3 i think. Resolution of 4 usually.

thank you all for all of your suggestions. except peak tailing, I also concern about if diastereomers can be seperated in regular GC column. I will try and post the update here.

thanks again