The present invention concerns bio-compatible medical devices and process for preparation thereof. The process includes electrostatically forming a first layer on a structure. The first layer can include a combination of at least one active substance and at least one polymer and/or binder. A second layer is formed on the structure to cover the first layer. The second layer can be a solvent or a combination of solvents. The evaporation of the second layer causes the first layer to reflow and bind to the structure.