I think it would really help if you could be more specific as to exactly what you are hoping to measure, here.

From the sounds of things, you want to lyse your cells completely, and measure both total released CK (effectively total cellular CK), and protein content of your lysate?

I am not entirely sure why you would want to do this, but assuming you do, then I assume the protein measurement is to normalise your CK data?

Could you not normalise to cell count instead of [protein] in your lysate? You could trypsinise your cells, spin them down, resuspend in PBS, take a small aliquot for cell counting and pellet the rest for resuspension in the CK buffer (which I assume acts as a lysis buffer in this context anyway).

I think you should not mix two protocols. Measure your enzyme activity separately in one aliquot since its activity depends on certain co-factors and minerals might be in that CK buffer, changing that will change activity. In the second aliquot your can determine protein. You are trying to find a short cut method. That might not be publishable and also might give you wrong results.

Hi,

I think you need to resuspend your cell and take one aliquot for your CK dosage and one for the BCA Protein Assay,

Combine two different kits and protocol in one sample is not a good idea

Best

Corentin