CO₂-switchable vesicles-network structure transition and drug release property

ABSTRACT

A series of amphiphilic triblock polymers based on poly(ethylene glycol) (PEG) and two symmetrical poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) blocks was synthesized via the Atom Transfer Radical Polymerization (ATRP) method. Conductivity, pH, and viscosity tests demonstrated the CO₂-switchability jointly; Cryogenic transmission electron microscopy (Cryo-TEM), Dynamic light scattering (DLS) revealed the self-assembly morphology transformation from unilamellar vesicle to network structure when bubbling CO₂. These changes were all attributed to the protonation of tertiary amine groups in PDMAEMA blocks and the mechanism was proved by ⁻H NMR. The vesicles have a relatively low release rate of drug; once stimulated by CO₂, the release rate will be accelerated. The polymeric vesicle has the possibility to find potential applications in drug delivery and release domains.

GRAPHICAL ABSTRACT

KEYWORDS:

• ATRP
• drug release
• triblock-copolymer
• vesicles

Additional information

Funding

This work was supported by the Scientific Research Innovation Team Project of Provincial Universities in Sichuan Province (No. 13TD0025), State Key Laboratory of Polymer Materials Engineering (Sichuan University) (No. KF201305).