Hybrid vesicles of pillar[5]arene/silica: Host-guest complexation and application in pH-triggered release

Pillar[5]arene/silica hybrid vesicles were constructed based on the amphiphilic and rigid properties of pillararenes, as well as the catalytic hydrolysis of tetraethoxysilane. Such vesicles integrated the high strength of silica and unique molecular recognition of pillararenes, both of which could tune the pH-triggered release behavior. [Display omitted] Integrating silica with organic nanoparticles can generate unique properties. Here pillar[5]arene/silica hybrid vesicles were constructed based on the amphiphilic and rigid properties of pillararenes, as well as the catalytic hydrolysis of tetraethoxysilane. Such vesicles exhibited the high strength of silica and unique molecular recognition of pillararenes, both of which could tune the pH-triggered release behavior. Furthermore, a rhodamine B derivative with hexyl group (RhB-C6) was synthesized, which can form a complex with the pillar[5]arene. Based on the host-guest interaction and high strength of silica, the hybrid vesicles could load more RhB-C6 and the rhodamine B was released more slowly compared with the organic vesicles.