Protein A Sepharose™ is a suspension of beads conjugated to native Protein A derived from Staphylococcus aureaus. Protein A has a high affinity for the Fc regions of IgG molecules from a variety of species, including human, mouse, rat IgG2c, cow IgG2c, goat IgG2, sheep IgG2 and rabbit.

Protein A have long term stability stability within pH range of 3 to 9 and short term stability within pH range of 2 to10. It can be used for immunoprecipitation and purification of monoclonal antibodies.