TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The inorganic substance is a non-carbon element in a substantially pure form. The non-carbon element is copper, silver and/or selenium.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The polymer matrix is a porous polymer matrix or a plasma polymer matrix. The polymer matrix is 5-150 (preferably 5-25) nm in thickness. The polymer matrix is formed from a monomer(s), which is alkylamines, preferably n-heptylamine and/or allylamine. The film is a multi-layered film comprising first and second polymer film layers, where the first film layer comprises a polymer matrix provided with one or more functional groups and, embedded within the polymer matrix, one or more nanoparticles of an inorganic substance(s), and the second film layer provides the film with additional functional characteristics and/or modify the properties of the first film layer. The second film layer modifies permeation of the inorganic substance(s) from the first film layer such as to provide a multi-layered film which releases the inorganic substance(s) in a sustained manner. The film comprises at least a third film layer which comprise a useful ligand. The second film layer is 5-25 nm in thickness. Preferred Method: The step of depositing and polymerizing the monomer(s) is performed by radio frequency glow discharge (rfgd) plasma polymerization. The film produced by steps (i) to (iii) constitutes a first film layer comprising a first polymer matrix provided with one or more groups and, embedded within the first polymer matrix, one or more nanoparticles of an inorganic substance(s), and the method further comprises (iv) applying a second film layer to a surface of the first film layer to produce multi-layer film, and (v) applying a third film layer to a surface of the second film layer. ACTIVITY - Cytostatic; Insecticide; Antibacterial; Immunosuppressive; Metabolic; Vulnerary.    MECHANISM OF ACTION - None given.    EXAMPLE - No suitable example given.