The present application relates to implantable therapeutic delivery system, its method of making and use. The therapeutic delivery system includes a nanofiber core substrate having proximal and distal ends, and an interior nanofiber wall defining an internal space extending longitudinally along the core substrate, with one or more therapeutic agents positioned within the internal space. A hydrogel surrounds the nanofiber core substrate, where the hydrogel includes 0.1% to 20% of an alginate mixture. The alginate mixture includes zwitterionically modified alginate and pure alginate in a ratio of 1:1000 to 1000:1 (v/v). Also disclosed is a thermo sealing device useful for the formation of the implantable therapeutic delivery system.