Abstract: A process for producing a collagen-based cross-linked biopolymer is provided in which a collagen solution free of low-molecular impurities is saturated with nitrogen protoxide, its concentration is brought to maximum 80 mass percent and the solution is exposed to an ionizing radiation in a dose of 0.5 to 15 kGy. An implant for hermetization of corneal and scleral wounds involved in eye injuries prepared from said bipolymer has the shape and size that provide for complete hermetization of said wounds. The method for its preparation comprises saturation of a collagen solution free of impurities and having a concentration of 0.2 to 1.3 mass percent, with nitrous oxide, filling of a mould with said solution and its exposure to an ionizing radiation in a dose of 0.5 to 15 kGy. The resultant blank is dried to a moisture content in its biopolymer of 30 to 50 mass percent, whereupon the blank is given the shape and size of a required implant.