pH-responsive resveratrol-loaded ZIF-8 nanoparticles modified with tannic acid for promoting colon cancer cell apoptosis.

Resveratrol (Res) is known for its potential in treating various types of cancers, with a particular advantage of causing minimal toxic side effects. However, its clinical application is constrained by challenges such as poor bioavailability, low water solubility, and chemical instability in neutral and alkaline environments. In light of these limitations, we have developed a pH-responsive drug delivery nanoplatform, Res@ZIF-8/TA NPs, which exhibits good biocompatibility and shows promise for in vitro cancer therapy. Benefiting from the mild reaction conditions provided by zeolitic imidazolate frameworks (ZIFs), a "one-pot method" was used for drug synthesis and loading, resulting in a satisfactory loading capacity. Notably, Res@ZIF-8/TA NPs respond to acidic environments, leading to an improved drug release profile with a controlled release effect. Our cell-based experiments indicated that tannic acid (TA) modification enhances the biocompatibility of ZIFs. 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT assay), Hoechst 33342/PI staining, cell scratch assay, Transwell and Reverse Transcription quantitative PCR (RT-qPCR) assays further demonstrated that Res@ZIF-8/TA NPs inhibited colon cancer cell migration and invasion, and promoted apoptosis of colon cancer cells, suggesting a therapeutic potential and demonstrating anti-cancer properties. In conclusion, the Res@ZIF-8/TA NPs pH-responsive drug delivery systems we developed may offer a promising avenue for cancer therapy. By addressing some of the challenges associated with Res-based treatments, this system could contribute to advancements in cancer therapeutics.