Described herein are nanofibers including an outer membrane and a core, wherein the outer membrane is made of fibroin and the core is a biocompatible and biodegradable polymer. Also described herein are a method for obtaining the nanofibers and the use thereof to convey bioactive molecules and/or particles and/or cells and/or in the treatment of diseases. Also described herein are powdered nanofibers, optionally suspended in an aqueous solution, a hydrogel system including the powdered nanofibers, and the use of the powdered nanofibers and of the hydrogel system to convey bioactive molecules and/or particles and/or cells and/or in the treatment of diseases.
