membrane filters for chromatography buffers - (Jun/30/2011 )

Hello,

My question is a rather silly one. we perform ion exchange chromatography and gel filtration chromatography of our recombinant proteins and our buffers are normally acidic pH 4 -5. We use 0.22 µ cellulose nitrate membrane filters to filter our buffers. Our bufffers basically are Na Acetate or Na Phosphate and also we sometimes do filter Tris buffer pH 6 -8

Recently someone suggested mixed cellulose esters for filtration purpose. which of tbe two is a better choice or is there some other membrane filter that can be used for our application kindly guide.

thanks for any suggestions or help.

membrane selection is usually dependent on factors such as chemical compatibility, solute retention and binding.

you will want to avoid using membranes that will dissolve in the solvent being filtered or that will leach into your medium.

you probably won't want to filter a protein solution through a cellulose nitrate filter.

for simple buffers you can use whichever you find fit.

here is a page that will guide you: millipore membrane resource center

and here is a compatibility guide (sorry, it doesn't include cellulose nitrate):