“…Various approaches have been investigated with respect to enhancing the bioavailability and decreasing the toxicity of quercetin through encapsulation in drug delivery systems including silica nanoparticles, PLGA and PLA nanoparticles, , chitosan nanoparticles, metal and metal oxide nanoparticles, , phospholipid vesicles, , micelles, an inclusion complex, carbon nanotubes, and other nanomaterials. , Metal–organic frameworks (MOFs), which are known as a group of green and environmentally benign nanomaterials due to their unique advantages such as high storage capacity, an easy functionalizing process, resistance structure, and cytotoxicity, have been garnered much attention in recent years. Their wide range of possible metal clusters and organic linkers gives rise to a variety of properties, making them suitable for various applications such as catalysis, nanomaterial synthesis, gas storage, , antibacterial activity, and especially drug delivery. , However, the weak coordinate bond in MOFs leads to low stability, which makes them nonpractical for biomedical applications. − Nevertheless, recent research indicated the excellent stability of the Zr-based MOF structure for drug delivery systems. , The synthesis of a high-capacity pressure-response drug release system of Zr-based MOF using novel ligand F–H 2 PDA ((2 E ,2′ E )-3,3′-(2-fluoro-1,4)phenylene)diacrylic acid) was reported by Qian et al The same research group fabricated another Zr-based MOF using N-heterocyclic ligand H 2 QDDA ((2 E ,2′ E )-3,3′-(quinolone-5,8-diyl)diacrylic acid) with pH-response releasing properties . One of the most investigated Zr-based MOF drug-controlled release systems is UiO-66. − A smart temperature-response drug release of UiO-66-PNIPAM (poly( N -isopropylacrylamide) was reported .…”