An intercalated covalent organic framework with donor-acceptor property for photothermal therapy

Based on the supramolecular assembly strategy, a donor-acceptor (D-A) covalent organic framework (COF) was developed by intercalating the electron-rich tetrathiafulvalene (TTF) between the layers of the COF which used 1,3,5-tris-(4-aminophenyl)triazine (TAPT) as an electron-deficient building unit. Due to the supramolecular D-A interactions, the obtained intercalated COF can efficiently convert luminous energy into thermal energy with a satisfying photothermal conversion efficiency up to 38.1 % for photothermal therapy. To further improve the biocompatibility and tumor targeting ability, the TTF-intercalated COF was coated with cancer cell membranes. In vitro and in vivo experiments demonstrated that the intercalated COF with D-A properties could effectively suppress the growth of tumors upon laser irradiation. This work provided a paradigm to feasibly construct D-A COF with promising photothermal performance for cancer treatment.