Looking for the optimal Cell Lysis Buffer

[Lahti]

I am looking for a cell lysis buffer that will help me solubilize a lysosmal cathepsin.  I am currently finding the Cathepsin in my cell lysate samples as well as my cell pellet.  The cathepsin may be membrane associated (with the plasma membrane or other cellular membranes).  What are detergents and/or buffers that might best aid me in removing a cathepsin from my cellular debris?

Lahti