The new ultra-high capacity TOYOPEARL AF-rProtein A HC-650F outperforms all other commercially available protein A media in terms of its IgG binding capacity, with over 65 g of IgG/L resin at 5-minute residence times. Even at a 2-minute residence time, its IgG capacity still exceeds 50 g/L, with feed stock concentrations ranging from 1.0 g/L to 10.0 g/L. Improved mass transfer characteristics enable it to maintain a larger percentage of its capacity at lower residence times compared to agarose-based, caustic stable resins