Immunoprecipitation is used to isolate a protein or other biomolecule of interest from cell lysate. Here’s what you need to do to perform immunoprecipitation:

• Add an antibody to an antigen-containing mixture that has been incubated to facilitate the formation of antigen-antibody complexes.
• Incubate the antigen-antibody complex with an immobilized antibody against the primary antibody (secondary antibody). Alternatively, you can incubate the antigen-antibody complex with protein A/G-coated beads.
• Wash the beads thoroughly.
• Elute the antigen from the beads with an acidic solution or sodium dodecyl sulfate (SDS).