Well-defined polyvinylamine-based copolymers: synthesis by organometallic-mediated radical polymerization and use in gene transfection

Polyvinylamine (PVAm) presents valuable properties like affinity for many supports, pH responsiveness, metal binding capacity, polyelectrolytes complexation, and is used in various applications including coatings, water purification or gas membrane separation. PVAm is commonly prepared by free radical polymerization of N-vinyl monomers followed by deprotection and release of the masked amino functions. However, examples of controlled synthesis of polyvinylamine-based copolymers are scarce because of the high reactivity of the propagating radicals deriving from non-conjugated N-vinyl monomers due to the lack of resonance stabilization. The present communication aims at reporting an efficient platform for producing tailor-made PVAms via organometallic-mediated radical polymerization (OMRP) of N-vinylacetamides followed by hydrolysis of the pendent amide moieties. In this case, cobalt(II) acetylacetonate was successfully used as controlling agent. The synthesis of a series of well-defined homopolymers, statistical and block copolymers with pendent primary and/or secondary amines having low dispersities, predictable molar masses and precise compositions, will be described. Finally, we will discuss the possible use of these polyvinylamine-containing copolymers as gene transfection agents. Some of them demonstrated high DNA transfection level in combination with high cell viability.