GTPase assay - (Aug/08/2021 )

Hi all, Im trying to do a gtpase assay using a kit and a few proteins of intrest. problem is my proteins are currently in PBS buffer, so the reaction is already full with phosphate...
does anyone has any ideas about how to do it properly? is dialysis with DDW a possibility? maybe another buffer instead of the PBS?
many thanks!

As you realized, the phosphate buffer will interfere with the assay. Exchange by dialysis will, most likely, leave enough phosphate behind to interfere. And dialysis against ddw may damage your proteins.

you can exchange buffer by gel filtration to eliminate traces of phosphate.

I will try that,

thanks!