Protein G-Sepharose beads are prepared by covalently coupling recombinant Protein G to 6% cross-linked Sepharose beads under proprietary endotoxin-free condition. The IgG binding capacity of Protein G-Sepharose is >20 mg of human or rabbit IgG per ml of wet beads. Protein G-Sepharose beads display high chemical & physical stability as well as high flow rate, hydrophilicity & high gel strength. It can be used for IgG purification and immunoprecipitation. Our Endotoxin-free Protein G-Sepharose also shows ability of reducing certain amount of endotoxin from serum or ascites samples.