WB; IH,Frozen; IH(P), Paraffin Immunohistochemistry (IHC) and Western Blotting (WB). A concentration of 0.5-1.0 µg/mL is recommended for WB. Human p53 (isoform 1) has a predicted length of 393 residues and MW of 44 kDa. A concentration of 0.5-2.0 µg/mL is recommended to detect p53 in formalin fixed and paraffin embedded tissues as well as formalin/acetone fixed frozen tissues. Biosensis recommends optimal dilutions/concentrations should be determined by the end user.