GenScript’s Protein A Resin FF is an affinity chromatography media designed for easy, one-step purification of classes, subclasses and fragments of immunoglobulins from biological fluids and from cell culture media. Protein A Resin FF can also be used for immunoprecipitation of proteins, protein complexes or antigens.The recombinant protein A ligand is coupled to 4% highly cross-linked agarose. The coupling is optimized to have a high binding capacity for immunoglobulins. The static binding capacity of Protein A Resin FF is greater than 40 mg human IgG/ ml settled resin. The dynamic binding capacity will vary depending on several factors such as target antibody, flow rate, etc. Table 1 lists the characteristics of Protein A Resin FF.

Protein A, a bacterial cell wall protein isolated from Staphylococcus aureus, binds to mammalian IgGs mainly at their Fc region. Native protein A has five IgG binding domains and many other domains with unknown functions. Recombinant protein A contains five high affinity IgG binding domains with other non-essential domains removed to reduce nonspecific binding. Since only the Fc region is involved in binding to recombinant protein A, the Fab region is available for binding antigens.