I'm going to extract proteins from bean plants. The recipe for the extraction buffer is 125mM Tris -HCl pH 8.8, 1% (w/v) SDS, 10% (v/v) glycerol, and 50 mM Na2S2O5. I add 200uL of the buffer to the material and centrifuge it for 1 min. Suspend it in ice for 1 min and centrifuge again for 10 min.

Could you please let me know if there is any thing wrong with this procedure? Do I need to use a protease inhibitor ?

Thank you.