Controllable Antibacterial Activity through Acid-Triggered Molecular Cage Release of Stored Ag+

Aiming for solving the emergence of drug-resistant bacteria worldwide, the construction of novel supramolecular self-assembly systems with antibacterial functions is attracting growing research attention. Herein, using dynamically reversible Schiff-base imine bonds as the assembly strategy, a three-dimensional pure organic cage, namely 4-cage, was obtained in high yield. By taking advantage of the bidentate chelating capability of its imine-based skeleton, 4-cage was demonstrated to serve as an Ag+-carrier. Owing to the acid-induced decomposition of this skeleton, the Ag+-loaded 4-cage can controllably release Ag+ through pH regulation, hence, as a proof-of-concept, it is proved to be applicable as a controllable release antibacterial reagent. Such pH-responsive Ag+-carried supramolecular architecture may shed light on the molecule design strategies for bacterial elimination in different environments, or for controllable functions in various other fields.