Rapid Synthesis of a Lipocationic Polyester Library via Ring-Opening Polymerization of Functional Valerolactones for Efficacious siRNA Delivery

The ability to control chemical functionality is an exciting feature of modern polymer science that enables precise design of drug delivery systems. Ring-opening polymerization of functional monomers has emerged as a versatile method to prepare clinically translatable degradable polyesters.¹ A variety of functional groups have been introduced into lactones; however, the direct polymerization of tertiary amine functionalized cyclic esters has remained elusive. We report a strategy that enabled the rapid synthesis of >130 lipocationic polyesters directly from functional monomers without protecting groups. These polymers are highly effective for siRNA delivery at low doses in vitro and in vivo.