Abstract: Present invention provides fully or partially biodegradable device for controlled delivery of drugs. In one embodiment, the present invention relates provides biodegradable device for controlled delivery of drugs, the device having micro or nano beads with a biodegradable shell and a core that contains a drug. The beads are enclosed in a skin or barrier layer that controls the flow of the drug from the biodegradable device to a region outside of the biodegradable device, wherein the beads are embedded in a biodegradable polymer matrix or a biodegradable foam or both. The biodegradable polymer matrix, biodegradable foam and/or the skin or barrier layer has a defined pore size such that physical movement of a droplet is restrained and free flow through serum but not through blood cells.