A donor-acceptor covalent organic framework as the promising construct for photothermal therapy

A donor-acceptor covalent organic framework (COF), TB-COF, constructed from an electron-rich building unit (donor) and an electron-deficient building unit (acceptor), was developed as a promising photothermal agent for photothermal therapy (PTT). Upon laser irradiation, significant photoinduced electron transfer (PET) occurs between the donor and acceptor in TB-COF, converting the absorbed optical energy to thermal energy and resulting in the ablation of tumor. TB-COF possessed satisfying photothermal conversion efficiency, reaching 43.65%, similar to materials commonly used for PTT. Moreover, hyaluronic acid (HA) was coated on TB-COF to improve its biocompatibility and achieve tumor targeting. Furthermore, in vitro and in vivo experiments confirmed satisfying photothermal anticancer efficacy of TB-COF-HA.