Zoraku wrote:
I don't have a lot of experience working with polysaccharides but if you are primarily interested in the amino acids themselves you might subject your extract to protein denaturation conditions such as 6M Urea, a very low or high pH aqueous solution or you can even attempt high salt to precipitate the proteins in hopes that it does not precipitate the amino acids (look up salting out for proteins). If you can precipitate the proteins in the extract you would just perform another centrifugation step and discard the pellet.
Do they make syringe filters that have a small enough pore size to catch proteins but let small molecules pass? Similar to the idea behind dialysis where the pore size allows molecules up to a certain size to pass through but larger molecules (such as proteins) cannot.
Just some ideas as I have never performed this kind of analysis...but hopefully this can provide insight or spark an idea from someone else.
Thank you for your reply Zoraku.
Your suggestions give me leads to look for in literature, and I had not thought of looking into these size-exclusion filters myself, so thank you for the insights.
As you already remarked, these procedures might also influence the recovery of the AAs, but that is something that has to be tested out..