The present invention provides a method for forming a multicompartmentalized vesicular structure comprising an outer block copolymer vesicle and at least one inner block copolymer vesicle, wherein the at least one inner block copolymer vesicle is encapsulated inside the outer block copolymer vesicle. The method comprises forming the at least one inner block copolymer vesicle by any method and adding block copolymers dissolved in a suitable solvent to a dispersion of the at least one inner block copolymer vesicle in an aqueous buffer under conditions that allow the block copolymers to form the outer block copolymer vesicle and encapsulate the at least one inner block copolymer vesicle. A multicompartmentalized vesicular structure and its uses are also provided.
