This invention demonstrated a unique cationic polymer that possesses a number features essential for systemic delivery of nucleic acids simultaneously. First, this polymer was synthesized by Zeta potential-regulated condensation of linear and branched amino group bearing oligomers through imidazole-4, 5-imine linkages, wherein the polymer diameter can be precisely adjusted from tens to hundreds nanometers by Zeta potential determinates such NaCl concentration. Most interestingly, the polymer was structured with sufficient network cavity to pack plenty copies of siRNA intramolecularly to form a polyplex of single polymer molecule. In addition, the polymer backbone degraded readily to non-toxic species and released nucleic acids in response to cellular environment due to the pKa (5.9) of its aromatically conjugated imine linage. Finally, the polyplex of single polymer molecule can be further encapsulated by a self-assembled a unilamella membrane of rationally designed triblock copolymer to which selected functional components such as cell targeting agents can be immobilized in optimized population. The lack of medicinally feasible synthetic carriers remains as the standing-hurdle blocking nucleic acids to covert from therapeutic actives to practical medicines. The present invention may serve as a "universal" vehicle to equip with variety of delivery functions for its defined structure and compatible flexibility.La présente invention concerne un polymère cationique unique qui possède un certain nombre déléments essentiels pour une administration systémique dacides nucléiques simultanément. Tout dabord, ce polymère a été synthétisé par condensation régulée par potentiel zêta doligomères portant des groupes amino linéaires et ramifiés par lintermédiaire de liaison imidazole-4,5-imine, le diamètre du polymère pouvant être ajusté avec précision de plusieurs dizaines à centaines de nanomètres par des facteurs déterminants du potentiel zêta tels que la concentration en NaCl.
