Direct Access to Polysaccharide-Based Vesicles with a Tunable Membrane Thickness in a Large Concentration Window via...

Area of Science:

• Polymer Chemistry
• Materials Science
• Nanotechnology

Background:

• Polymersomes are vesicular nano-objects formed by amphiphilic copolymer self-assembly.
• Synthetic block copolymers readily form polymersomes, but polysaccharide-based ones remain challenging.
• Polysaccharide-based polymersomes offer unique biocompatibility and potential applications.

Purpose of the Study:

• To develop a method for synthesizing pure polysaccharide-based polymersomes.
• To investigate the self-assembly behavior of dextran-g-poly(2-hydroxypropyl methacrylate) (Dex-g-PHPMA) copolymers.
• To explore the influence of graft length on polymersome morphology.

Main Methods:

• Polymerization-induced self-assembly (PISA) was employed.
• Photomediated reversible addition-fragmentation chain transfer (RAFT) polymerization at 405 nm was used.
• Characterization techniques included TEM, cryo-TEM, SAXS, AFM, and DLS.

Main Results:

• Pure vesicles were successfully formed from Dex-g-PHPMA copolymers in aqueous solution.
• Vesicle formation was achieved over a broad range of solid concentrations (2.5%–13.5% w/w).
• Increasing graft length (X̅) led to thicker vesicle membranes, not morphological changes.

Conclusions:

• PISA is an effective strategy for creating polysaccharide-based polymersomes.
• Dex-g-PHPMA copolymers demonstrate controllable self-assembly into vesicles.
• The findings facilitate the development of novel polysaccharide nanostructures for various applications.