A novel fabricated material with divergent chemical handles based on UiO-66 and used for targeted photodynamic therapy

Abstract

A unique zirconium-based framework named N₃-UiO-66-NH₂, which can be used as a fabricated material to achieve the dual functional chemical modification of UiO-66, was synthesized and demonstrated. This work offers a facile and selective covalent post-synthetic modification of UiO-66 by different chemical reactions related to azide- and amino-groups, respectively. Using N₃-UiO-66-NH₂ as a fabricated material, a newly dual functionalized MOF named E-UiO-66-Pc, in which a carboxyl substituted zinc phthalocyanine (Pc) and Erlotinib (E) were employed as a photosensitizer and targeting moiety, was designed and synthesized via amidation and click chemistry, respectively. The photochemical properties, tumor specificity and anticancer activity of E-UiO-66-Pc were investigated. We further demonstrated that it is viable to achieve facile and selective covalent post-synthetic modification of N₃-UiO-66-NH₂ with Pc and E and obtained a series of functionalized UiO-66 nanomaterials. The Pc-containing UiO-66 nanomaterials exhibit high photodynamic activity, and the Erlotinib-containing UiO-66 nanomaterials show obvious dark cytotoxicity and high selective affinity to cancer cells. E-UiO-66-Pc reveals cooperative photodynamic and targeted anticancer activity. To the best of our knowledge, this is the only example of UiO-66 with two different chemical handles (–NH₂ and –N₃) anchoring to different functional molecules via amidation and click chemistry, respectively.