Abstract: The present invention relates to a substrate with a solid support coated with a porous hydrophobic polymer layer or film, wherein said polymer layer or film is coated with a water-immiscible hydrophobic liquid forming a stable film on the polymer surface. The present invention further relates to a method of forming a protein- and cell-repellent surface, comprising the steps of providing a substrate with a solid support coated with a porous hydrophobic polymer layer or film, and applying a water-immiscible hydrophobic liquid to said porous hydrophobic polymer layer or film, a respective method of preventing the formation of biofilms, adhesion of cells and bacteria, and/or migration of cells and bacteria on a surface, as well as the use of a porous hydrophobic polymer layer or film that is coated with a water-immiscible hydrophobic liquid for forming a protein-, cell- and bacteria-repellent surface.