Water insoluble cationic poly(ester amide)s: synthesis, characterization and applications

Abstract

We reported a new family of water insoluble, biocompatible and biodegradable cationic arginine and phenylalanine based poly(ester amide)s (Arg-Phe-PEAs) for potential biomedical applications. The Arg-Phe-PEA consists of 3 building blocks: amino acids, diols, and dicarboxylic acids and was prepared from both L-arginine and L-phenylalanine amino acids by solution polycondensation. The structure and properties of Arg-Phe-PEAs were characterized by standard physicochemical methods. In vitro biological tests of the Arg-Phe-PEAs included enzymatic biodegradation, cell attachment and proliferation, and macrophage inflammation tests. The enzymatic biodegradation tests showed that the biodegradation rate of Arg-Phe-PEAs can be controlled by regulating the polymer composition (the ratio of Arg to Phe). The cellular tests indicated that the bovine aortic endothelial cells (BAECs) have very good cell attachment and proliferation on the Arg-Phe-PEA surface. The in vitro inflammation data showed that the Arg-Phe-PEAs induced far lower inflammatory response than FDA approved biomaterials. By a nano-precipitation method, Arg-Phe-PEAs were formulated into nanoparticles (NPs) with particle sizes below 200 nm. The protein release profiles from Arg-Phe-PEA NPs showed that the introduction of arginine significantly enhanced the protein encapsulation efficacy and changed the protein release rate compared with pure phenylalanine based poly(ester amide)s (Phe-PEAs).