Cellulose nanofibrils composite hydrogel with polydopamine@zeolitic imidazolate framework-8 encapsulated in used as efficient vehicles for controlled drug release

Abstract Herein, we report a nanocellulose hydrogel that has a packaging structure for on-demand drug release. Zeolitic imidazolate frameworks-8 (ZIF-8) were grown on the surface of polydopamine (PDA) to produce PDA@ZIF-8 nanoparticles. The obtained PDA@ZIF-8 nanoparticles were then incorporated into a network of cellulose nanofibrils (CNFs) to fabricate a PDA@ZIF-8/CNFs composite hydrogel. The loading ratio of the drug tetracycline hydrochloride (TH) was 58%. A slight burst release behavior was observed at the beginning, and the composite hydrogel presented a significant pH-dependent release behavior. The drug delivery time of the PDA@ZIF-8/CNFs composite hydrogel was 3.5 times longer than that of the PDA/CNFs composite hydrogel. Furthermore, NIR light radiation accelerated the drug delivery rate. The drug release mechanism was mainly driven by anomalous transport. Importantly, the novel PDA@ZIF-8/CNFs composite hydrogel was found to be biocompatible according to in vitro cytotoxicity test. Because of its unique multiple drug release responses, the PDA@ZIF-8/CNFs composite hydrogel may be used in future clinical applications as a promising drug delivery carrier.