The folin phenol method was used to quantitatively detect the activity of active enzymes in protein. The operation is relatively simple, as long as there is a spectrophotometer and a water bath box. It is not expensive to import and repackage by folin phenol method, and it needs a little casein and tyrosine. You can do it yourself.

Qualitative analysis is simpler, just use 1% skimmed milk powder tablets.