Silk cocoon membrane-based immunosensing assay for red blood cell antigen typing

•The application of natural free-standing silk cocoon membrane in blood typing by immunosensing assay was proposed.•The cocoon membranes were treated with heat and detergent to increase wettability.•The cocoon membranes were functionalized by affinity binding with specific silk monoclonal antibodies and crosslinking antibodies.•Blood grouping antibodies were coupled to functional cocoon membranes to form the immunosensor for blood typing.•This affinity biosensor yielded accurate visualization results for ABO and RhD blood grouping within 30 s.