salt precipitation of diverse collagen types - (Feb/23/2006 )

Hi,

I want to isolate different types of collagen from tissues.
So, I've grinded the tissues, let them incubate for 2 days with guanidine-hcl to get rid of the proteoglycans.
But now what?
I got a protocol from "the ecm, a practical approach" in which they isolate types II, IX and XI by dialysis. But I also want more types.
So I've searched the internet and articles and I found different salt precipitations with NaCl, namely:
2.5M for type I, 0.9M for type II, 1.8M for type III, 1.8M for type IX and 1.2M for alpha 1,2 and 3 (chains of col 9).

Can anybody tell me if I indeed get both type III and IX with 1.8M?
And do you know concentrations for other types? I also want type VI and XI.
Or a whole different protocol with salt precipitation or dialysis is also fine.