You can take the same which you used during the first step which in your case is PBS buffer and carry dialysis overnight at 4 degree.

I used Tris-HCl in my case during ammonium sulphate precipitation and used the same buffer for dialysis.. worked well for me.

Good luck

Use a buffer for which there is an expectation that the protein will be stable in it, based on existing literature for the same enzyme or a closely related one. Dialysis should be done cold, such as 4oC.

Buffer with minimum salt concentration but enough to maintain physiological state of protein otherwise proteins will aggregate.

You can use PBS or 90 mM NaCl as dialysis buffer , dialysis should be done at 4 degree.

First of all I will ask have you measure your activity in both the ppt. & the super. after ammonium sulfate pption. to check if your enzyme is present?

I would suggest that you use PD10 column to get ride of all salt ,you can use PBS buffer to wash the column & obtain your enzyme, it is much easier than dialysis and takes much shorter time than dialysis.

You can take the same which you used during the first step which in your case is PBS buffer and carry dialysis overnight at 4 degree.

I used Tris-HCl in my case during ammonium sulphate precipitation and used the same buffer for dialysis.. worked well for me.

Good luck