Executive Summary : | Synthetic polymers are crucial in biomedical research, including drug delivery in cancer research. They are biocompatible, biodegradable, and bio-resource-based, with minimal side effects under physiological conditions. Synthetic polypeptides based on natural ?-amino acids mimic protein-like assemblies for understanding and technology development. Polypeptides are typically produced via ring opening polymerization (ROP) of 5-member N-carboxy anhydrides (NCA) of ?-amino acid natural resources. However, ?-sheet polypeptides are one of the least explored synthetic systems due to uncontrollable precipitation. A recent development aimed to address this issue by developing a "steric-ROP" strategy to build high molecular weight ?-sheet polypeptides. This process involves conformational transition from ?-sheet to ?-helix, producing freely soluble polymers with excellent "living ROP polymerization" characteristics. The research proposal aims to design new classes of ?-sheet polypeptides based on poly(?-serine), poly(?-cysteine), poly(?-tyrosine), and poly(?-threonine)s and expand the synthetic methodology to their unexplored polypeptide block copolymers. |