the present invention discloses new nanoassembled complexes consisting of a central nucleus formed by a high - affinity interaction from nucleic acids and avidin , wherein said nucleus is stabilized in aqueous solutions , even saline , and protected from further unspecific unwanted interactions by means of suitable polymeric agents capable to mask totally or partially the nucleus itself . the nanocomplexes obtained have been shown to be stable in aqueous solutions and to have nanoparticle features . in addition , the nano - complexes have shown characteristics useful for use in biotechnological field and in nanomedicine .