No, your primary antibody does not need to be conjugated for using with the Pierce Fast Western Blot Kit, ECL Substrate (cat. No. 35050, 35055). The kit includes all necessary reagents except the primary antibody, and it works with both mouse and rabbit primary antibodies. The HRP reagent directly binds to both mouse and rabbit primary antibodies, thus, a secondary antibody is not needed.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.