Hydrogen-bonding mediated self-assembly of amphiphilic ABA triblock copolymers into well-defined giant vesicles

Abstract

Giant vesicles represent an extremely useful system to mimic biomembranes; however, the available methodologies towards easy and direct vesicle construction are still scarce. By designing a hydrogen-bonding (H-bonding) amphiphilic ABA triblock copolymer and introducing 2,6-diaminopyridine (DAP) moieties as pendant groups into the middle hydrophobic block, we demonstrate a straightforward and effective self-assembly strategy to form giant vesicles (∼3 μm in diameter) via a combination of H-bonding and amphiphilic interactions. The spatial distribution of these DAP moieties is tightly related to local organization, featuring an interchain H-bonding association ascribed to the dimerization of DAP moieties, thus offering a straightforward pathway towards effective generation of giant vesicles, as proven by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations. Moreover, atomic force microscopy (AFM) studies further prove the hollow interior of these vesicular morphologies. This study provides a new opportunity for the design of supramolecular polymers, serving as polymeric vesicle scaffolds in materials design and may act as red-blood-cell-like containers in delivery and microreactor applications.