[khaza]

I have a membrane and want to determine the MWCO of it. So i will be using PEG 4000 and PEG 10000 as the solute. What is the best instrument to test the MWCO?

[Babcock_Hall]

Is this a homework problem?  What are your thoughts?

[khaza]

no this is not homework. Im thinking to use the GPC, but i am only using single solute, not a mixture.

[P]

As long as your GPC solvent doesn't cause the polymer to crash out of its PEG solvent in the column then it should work no? What other MW measurement options do you have? Light Scattering?

[Babcock_Hall]

What about testing the membrane in an ultrafiltration experiment with PEGs of various molecular weights?

[khaza]

yes a light scattering, but i dont have any idea how it works.

[khaza]

yes im currently doing an unltrafiltration with my membrane using various PEG MW let says 4000 and 10000. But then, after the filtration occured, what kind of instrumen do i need to use to determine the 90% rejection since this is a single solute which is PEG, i dont have any idea of any other instrument other than GPC and how does it work