Versatile preparation of vesicle from amphiphilic bottlebrush block copolymers

Polymeric vesicles show vast potential in drug delivery for the treatments of various diseases. In this work, we report here an advanced polymeric vesicle formed by amphiphilic bottlebrush block copolymers (BBCPs), which have a large size and can resist different kinds of surfactants in a degree. The amphiphilic BBCPs with controlled molecular weights and narrow molecular weight distributions were synthesized by ring-opening metathesis polymerization of norbomyl-poly (ethylene glycol) (NPEG) and norbornyl-trithiocarbonates (NTTA) followed by reversible addition-fragmentation chain transfer (RAFT) with styrene. GPC and (HNMR)-H-1 were used to characterize BBCPs. Turbidity measurements, transmission electron microscopy, and scanning electron microscopy were used to explore the morphologies of the aggregation. Depending on the content of water added, many intermediate structures like compound vesicles and sphere could be found. After lyophilization, the BBCP vesicles happended a fusion and can retain vesicle morphology and show some stability in the presence of sodium dodecyl sulfate (SDS), hexadecyl trimethyl ammonium bromide (CTAB), Brij 78P and sodium chloride. This work serves a promising way to construct stable vesicles with BBCPs for biomedical applications.