Page 1 of 1
Acetonitrile elution
Posted: Wed May 18, 2011 7:56 pm
by konkon
I am working with a small peptide (1.3KDa). I am following some literature to purify it in Sep-pak C18 column. Everything is kind of straightforward but I do not have a lyophiliser (we are not a chemistry lab). So I was wondering, the elution protocol from the paper suggests 50% acetonitrile:50% water for elution. If I would use 100% acetonitrile for elution and then use a vaccum evaporator to evaoparate the Acetonitrile from my peptide, would that work, or any reasons that this cannot work? This way I should not have the issue of having the water left over after the vaccum evaporator.
Any suggestions are welcomed. Thanks, konkon
Re: Acetonitrile elution
Posted: Wed May 18, 2011 9:22 pm
by tom jupille
You can certainly try it. Possible issues to watch out for:
Is your peptide soluble in 100% ACN?
Will 100% ACN elute additional impurities?
Re: Acetonitrile elution
Posted: Wed May 18, 2011 9:41 pm
by konkon
Thank you for the comment. I suppose I could use 50:50 to do the first purification, back dilute the acetonitrile concentration, rebind and elute with 100%. Not sure if the peptide is soluble at 100% but does it really matter if I am going to evaporate the acetonitrile later on?
Thank you.
Re: Acetonitrile elution
Posted: Thu May 19, 2011 12:57 am
by tom jupille
does it really matter if I am going to evaporate the acetonitrile later on?
Yes, because it has do dissolve in the ACN in order to be eluted from the cartridge. A small peptide *should* be soluble in ACN, but "just because I'm paranoid doesn't mean that the world is *not* out to get me."

!