An all-aqueous route to polymer brush-modified membranes with remarkable permeabilites and protein capture rates

► Macroinitiator adsorption allows aqueous growth of polymer brushes in 5 min. ► Proteins bind to highly permeable, brush-modified membranes in 35 ms. ► Modified membranes exhibit high protein-binding capacities (100 mg/cm3). ► Brushes containing Ni2+ isolate >90% of a His-tagged protein from a cell extract.