Nanoscale covalent organic framework for the low-temperature treatment of tumor growth and lung metastasis

Photothermal therapy (PTT) has shown promising applications in tumor therapies. However, due to laser-induced nonspecific heating and heat diffusion, high levels of hyperthermia (>50°C) tissues often increase the risk cancer recurrence metastasis, which causes patient pain destroys surrounding normal cells tissues. It is therefore important develop photothermal strategies that have excellent therapeutic efficiencies under low-temperature conditions (≤45°C). In addition, heterogeneity complexity tumors require development combinatorial antitumor treatments as efficiency monomodal PTT not currently sufficient. Herein, we adopted a stepwise synthetic approach highly efficient multimodal agent GA@PCOF@PDA by successive bonding defect functionalization (BDF), guest encapsulation, surface modification steps. The covalently grafted porphyrinic photosensitizers (Por), encapsulated gambogic acid (GA), surface-modified PDA film are independently responsible for photodynamic (PDT), heat-shock protein 90 (HSP90) down-regulation chemotherapy (CT), PTT. This proof-of-concept study illustrates an efficient, generalized design high-performance covalent organic framework (COF)-based nanoagents can be easily tailored combine different modalities improved theranostics at low temperatures.