The invention is directed to a composition comprising: a substrate polyurethane a hydrogel forming polymer on at least one of the two faces of the polyurethane substrate and silver nanoparticles on the at least one face comprising the hydrogel forming polymer wherein the hydrogel polymer is covalently linked to the polyurethane substrate. The invention is also directed to a process for the preparation of the composition comprising the following steps: i. Impregnating at least one face of the substrate polyurethane with a solution comprising a reactive diolefin and the free radical initiator ii. Extracting the polyurethane from the solution and, after drying, immerging the polyurethane in a solution containing the initiator catalyst and the hydrogel forming polymer and obtaining a polyurethane covalently bond with a hydrogel forming polymer iii. Depositing silver salts on the polyurethane-hydrogel by immerging the polyurethane- hydrogel in a solution of the silver salt, followed by reduction with chemical or physical methods iv. Collecting the polyurethyane-hydrogel-silver product from the solution and drying the obtained dressing in air.
