Recovery of antibodies with Protein A affinity chromatography columns has become the standard for the biotechnology industry. Membrane affinity chromatography has not yet experienced extensive application due to the lower capacity of membrane supports compared to chromatographic beads. In this work, new affinity membranes endowed with an interesting binding capacity for human IgG are studied in view of their application in the capturing step of a monoclonal antibody production process. The membranes have been extensively tested with pure IgG solutions and with a cell culture supernatant containing IgG1. The effects of feed flow rate and IgG concentration on the separation performances have been studied in detail, considering in particular binding capacity, selectivity and recovery. These new high capacity affinity membranes appear good candidates to avoid the throughput limitations and other well-known drawbacks of traditional bead-based chromatographic columns.