WB; IH,Frozen; IH(P), Paraffin Immunohistochemistry (IHC) and Western Blotting (WB). A concentration of 0.25-0.50 µg/mL is recommended for WB. Human Collagen III (isoform 1) has a predicted length of 1,466 residues and a MW of 139 kDa. A concentration of 0.5-1.0 µg/mL is recommended to detect the protein in formalin fixed and paraffin embedded tissues. Heat mediated antigen retrieval is required. A concentration of 0.5-1.0 µg/mL is recommended to detect the protein in formalin/acetone fixed tissues. Biosensis recommends optimal dilutions/concentrations should be determined by the end user.