Bicomponent hydrogels assisted templating synthesis of hierarchically porous ZIF-8 for efficient antibacterial applications

A hierarchically porous ZIF-8 (HZIF-8) with pH-responsive and antibacterial activity was constructed us-ing bicomponent hydrogel as template. The synthesized HZIF-8 was applied to load the antibacterial drug berberine hydrochloride (BBH). In vitro release studies showed that BBH@ZIF-8 and BBH@HZIF-8 displayed a sustained drug release profile, and the drug release rate increased with the decreasing pH value. The BBH@HZIFS with the highest drug loading capacity also had the highest cumulative drug re-lease rate. At the end of 24 h, the cumulative release of BBH encapsulated in HZIFS, HZIFM and HZIFP were 92.07%, 86.60% and 88.00% at pH 5.0, respectively, higher than that of ZIF-8 (84.07%). Furthermore, in vitro antibacterial testing revealed that BBH@HZIF-8 exhibited efficient and long-lasting effects against Staphylococcus aureus, which was attributed to the synergistic bacteriostatic effect of Zn2+ and BBH re-leased by the structural degradation of BBH@HZIF-8 under acidic conditions. In conclusion, the study provides a strategy for synthesizing HZIF-8 and demonstrates the potential of HZIF-8 as a pH-responsive nanoplatforms for antibacterial applications.(c) 2022 Elsevier B.V. All rights reserved.