DNA-Grafted Polypeptide Molecular Bottlebrush Prepared via Ring-Opening Polymerization and Click Chemistry

Abstract

A new type of DNA grafted polypeptide molecular brush was synthesized via a combination of ring-opening polymerization (ROP) and click chemistry. This conjugation method provides an easy and efficient approach to obtain a hybrid DNA-grafted polypeptide molecular bottlebrush. The structure and assembly behaviors of this hybrid brush were investigated using electrophoresis, UV–vis spectroscopy, transmission electron microscopy (TEM), and atomic force microscopy (AFM). Hierarchical supramolecular assemblies can be obtained through hybridization of two kinds of polypeptide-<i>g</i>-DNA molecular bottlebrushes containing complementary DNA side chains. We further demonstrated that such polypeptide-<i>g</i>-DNA can be hybridized with ds-DNA and DNA-grafted gold nanoparticles to form a supermolecular bottlebrush and hybrid bottlebrush, respectively. In addition, DNA-polypeptide hydrogel can be prepared by hybridization of polypeptide-<i>g</i>-DNA with a linker-ds-DNA, which contains the complementary “sticky ends” to serve as cross-linkers