PEG-Functionalized Hollow Multishelled Structures with On-Off Switch and Rate-Regulation for Controllable Antimicrobial Release.

The construction of responsive antimicrobial carriers with multifunctional and controllable release is an attractive but challenging proposition. Recently developed hollow multishelled structures (HoMSs) offers structural advantages, such as easily modifiable surfaces and mutually influenced shells. Herein, we report a novel pH-responsive antimicrobial carrier having hierarchical shells as multilevel responsive bodies using polyethylene glycol (PEG) as a gated regulator. The interaction between PEG-functionalized shells endows them with a pH-responsive switch and rate-regulator capability. These features are present in the form of rapid release of molecules wrapped in the outer shell, and controlled diffusion of antimicrobials stored in the inner shell by electrostatic interaction, resulting in a long-lasting mildew resistance for up to 71 days. The versatility of the hierarchical interactions of HoMSs will inspire the design of promising smart drug carriers.