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
