One-Shot Intrablock Crosslinking of Linear Diblock Copolymer to Realize Janus-shaped Single-Chain Nanoparticle.

Developing an efficient and versatile process to transform a single linear polymer chain into a shape-defined nanoobject is a major challenge in the fields of chemistry and nanotechnology to replicate sophisticated biological functions of proteins and nucleic acids in a synthetic polymer system. In this study, we performed one-shot intrablock crosslinking of linear block copolymers (BCPs) to realize single-chain nanoparticles (SCNPs) with two chemically compartmentalized domains (i.e., Janus-shaped SCNPs). Detailed structural characterizations of the Janus-shaped SCNP composed of polystyrene- block -poly(glycolic acid) revealed its compactly folded conformation and compartmentalized block localization, similar to the self-folded tertiary structures of natural proteins. Versatility of the one-shot intrablock crosslinking was demonstrated using several different BCP precursors. We further discovered the excellent self-assembling behavior of the Janus-shaped SCNP to produce miniscule microphase-separated structures, representing the significant potential of the presented compartmentalization protocol, for developing biomimetic synthetic-systems, as well as for industrial nanofabrication applications.