Assembly of Free-Standing Polypeptide Films via the Synergistic Combination of Hyperbranched Macroinitiators, the Grafting-From Approach, and Cross-Chain Termination

摘要

Synthetic peptide-based materials with various macromolecular architectures are of interest because of their tuneable functionalities, conformations and specific stereochemistries, as well as their biocompatibility and (bio)degradability, which makes them desirable for nano(bio)technology applications, especially in polymer therapeutics. In particular, hollow polymeric capsules (i.e., coreless free-standing cross-linked films capable of cargo encapsulation) comprised of amino acid constituents would be attractive as biomolecular devices. To date, the fabrication of peptide-based capsules have utilized techniques driven by self-assembly, such as the layer-by-layer (LbL) deposition of charged biopolymers. Alternatively, the formation of degradable peptide-based cross-linked capsules has also been achieved by the polymerization of dopamine-modified polypeptide chains. Although these approaches allow for fine control over the capsule film properties, the synthesis of pre-function-alized polypeptides (or proteins) and subsequent film generation often involves multi-step processing and/or synthesis. On the other hand, the surface grafting approach has also been utilized to fabricate polypeptide films on various substrates such as silicon wafers, silica particles, and more recently, magnetite nanoparticles with defined composition and secondary structure, which has allowed for pH-triggered release, drug/ protein conjugation and surface modification.