Dialysis Buffer for Recombinant Protein - (Jun/26/2008 )

The protein is already purified in Qiagen's Buffer E ( which is 100mM NaH2PO4, 10mM Tris Cl, 8 M urea, pH 4.5). I'm trying to dialysis the protein to storage buffer without urea. I've tried to reduce the urea to 6.5 M. The buffer was then stepped down every 12-24 hours to 5M, 4.5M, 1M, 0M. The problem is that when it procedes to 5 or 4.5 M, the urea will coagulate. Does the protein concentration matter or is there another solution? Thanks.

It's not the urea that is precipitating, it's your protein. It will still be a good immunogen, if that's the goal. If you want the protein to refold and be soluble, you are about to learn an art that will be specific to your protein. I think cellcounter gave you a good link.

Another good site is Refold at Monash University. http://refold.med.monash.edu.au

You could try a fast dilution by dripping the protein into a large volume of buffer.

Another good site is Refold at Monash University. http://refold.med.monash.edu.au

You could try a fast dilution by dripping the protein into a large volume of buffer.

Another good site is Refold at Monash University. http://refold.med.monash.edu.au

You could try a fast dilution by dripping the protein into a large volume of buffer.