Hi, I'm doing Azocasein assay for plant extract. It has color so, for my blank initially I put extract, buffer, TCA centrifuge (no incubation) then NaOH. Somehow I think NaOH enhance the color my extract way more.. so the abs reading for my blank is higher than my sample. I got neg value. While for my neg control I use buffer + Azocasein subs with incubation, TCA and NaOH. And the abs reading is lower than my sample. So it's okay. But for my blank how?