A medical device having a biodegradable coating comprising an inorganic material complexed to macromolecules. Biodegradation of the biodegradable coating releases nanoparticles of the inorganic material with macromolecules complexed to the released nanoparticles. The inorganic material may be applied directly onto the medical device as a nanostructured coating or be dispersed within or under a layer of biodegradable polymer. The medical device body may comprise a biodegradable metallic material. Also provided is a method of delivering macromolecules to body tissue using the medical device of the present invention.