Blocker™ Casein

Optimize the concentration of primary and secondary antibodies. In some cases, increasing the concentration of blocking agent (BSA or non-fat dry milk) or usiing an alternative blocking solution such as Starting Block or SuperBlock may reduce background signal. After incubation with the primary antibody, wash at least 2 times with TBST (include 0.5 M NaCl in one or more of the wash steps). Avoid Nonidet P40 or Triton X-100 in buffers because protein detection is decreased when these detergents are used.

Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.

Blocker Casein (Cat. No. 37582, 37528, 37528X3) is a ready-to-use, 1% (w/v) solution of purified casein in phosphate-buffered saline (PBS). It is a stable, thimerosal-free formulation and is already at the optimal concentration for most applications. However, it can be diluted further if needed.

Find additional tips, troubleshooting help, and resources within our Protein Biology Support Centers .