disclosed are hydroxyl radial generating devices , comprising : a substrate layer ; and a pyrite layer configured to produce hydroxyl radicals . another aspect relates to a method for producing a hydroxyl radical generating device , comprising : providing a polymeric substrate layer ; placing a layer of pyrite on a surface of the polymeric substrate layer to form a multi - layer structure ; and applying heat to the multi - layer structure such that at least the surface of the polymeric substrate layer contracts ; wherein the layer of pyrite contracts to a lesser extent than the surface of the polymeric substrate layer providing a textured surface comprising the pyrite layer . also disclosed is a method of analysis , comprising : placing a solution comprising a biological substance on a sample site of a hydroxyl generating device comprising a surface of pyrite ; incubating the solution ; and analyzing a sample including proteolytic fragments of the biological substance .