Disclosed herein is a structure having: a porous polymeric film permeated by a first extracellular matrix material; and a topcoat layer comprising a second extracellular matrix gel disposed on the film. Also disclosed herein is a method of: providing a porous polymeric film; permeating the film with a first extracellular matrix material; and applying a topcoat layer of a second extracellular matrix material to the film. Also disclosed herein is a method of: laser-machining holes through a film comprising collagen to form a web-like structure.