Chromatography Forum

Hi all,

I am new in the group and I am looking for some advice on the analysis of diethanolamine (DEA) by GC (without derivatization)

Thanks,

Maria

Without derivatization, you'll need a very polar column and high temperatures, not so easy. Most agencies suggest against using diethanolamine in products these days, or stuff that can degrade to form DEA. Personally, I derivatize.

We are not using DEA but I guess we will be required to test for that in the near future. However we know the results will be negative we need to have a method in place to prove it.

So I guess what I really looking for is able to detect DEA in drug products, either by GC or maybe HPLC...
Thanks,

You'll need to get agreement (such as from your QA department - good luck) as to what detection limit will be considered "zero". You can't have a crappy method and then just report "none detected". Sorry, I can't elaborate on our GC derivatization procedure for DEA, that's considered proprietary.

I don't know whether the information is any use for your application but DEA will chromatograph underivatized on a Tenax TA packed column.

Thanks Mike....I will look into that column!

Sorry to be so retro but why not use TLC and ninhydrin detection to prove the zero expected result. It would be faster than GC because you can run samples and spiked samples and standards all at the same time.

Demonstrate that DEA is present at less than 0.1% or 0.01% and you are done.

Cheap, fast, and undeniably proven. You can use a photocopier or a Camag Scanner to document the negative result.

best wishes,

Rod

OSHA offers analytical method for DEA determination in Air. You can modify it for your matrix or extract.

http://www.osha.gov/dts/sltc/methods/pa ... /2018.html

I thought the classical was a packed column
Diatomaceous earth precoat with KOH with carbowax at 5 % or similar.

I suspect a carbon sieve column with KOH and carbowax would be a better proposition as the support would be more stable. This would be my choice.

Bob M