By combining molecular self-assembly nanosphere lithography and reactive ion etching, large-scale nanopatterns of antibodies are fabricated for direct application in state-of-the-art on-chip immunosensors. Using in-situ surface plasmon resonance, the patterns are studied in view of their antigen binding capacity, which shows an increase of up to 120% solely in the case of antibody confinement into the nanopatches by means of a nonfouling embedding matrix (see figure).