Poly(ester urea)s: Synthesis, material properties, and biomedical applications

Amino acid-based poly(ester urea)s (PEUs) are an emerging class of highly tunable, degradable polymers that have found utility in a wide scope of biomedical applications. PEUs possess three points of tunability at the amino acid side chain, diol length, and copolymer stoichiometric ratio, resulting in a broad range of chemical, thermal and mechanical properties. PEUs are interesting biologically because they degrade into naturally occurring amino acids, urea, oxidized products from the diols, and carbon dioxide, each of which can be metabolized or excreted. The diversity in structure, properties and biodegradation characteristics of PEUs have led to their exploration in a number of pre-clinical applications including hernia repair, adhesives, radiopaque implants, and drug delivery. In this review, we provide a thorough history of PEU synthesis methodology. The polymer properties arising from the various synthetic methods including mechanical, thermal, and biocompatibility properties are also summarized. This review concludes with an overview of progress in the primary applications of PEUs to date including hard and soft-tissue engineering, radiopaque biomaterials, adhesives, and drug delivery.