Uronic acid standards

[sdegrace]

I'm looking for samples of guluronic acid and mannuronic acid. I want to assay alginic acid and I'm interested in exploring the idea of deliberately hydrolyzing it and looking for the individual subunits chromatographically (I want to see if I can do a little better than USP<311>). However, I can't find anyone who sells these compounds. Aldrich just turns up alginate, and Google also turns up a blank. Does anyone know of anywhere that specializes in selling carbohydrates? I don't even need anything like a certified reference standard at this point, just a sample.

Thanks for any help anyone can give!

Stephen

[johnboy]

we have always got standards of these from Sigma - I can't belive that they no longer supply them?

[sdegrace]

You wouldn't happen to know a part number? Any time I search for guluronic acid, guluronate, mannuronic acid or mannuronate on the Sigma-Aldrich web site I keep getting hits for alginic acid.

[sdegrace]

I just called Sigma... they say they don't carry those products. Of course, the dude is probably looking it up with the same web site I am .