Affiliation: | 1. Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin, 150001 P. R. China The Key Laboratory of Rare Earth Functional Materials and Applications, Zhoukou Normal University, Zhoukou, 466001 P. R. China;2. The Key Laboratory of Rare Earth Functional Materials and Applications, Zhoukou Normal University, Zhoukou, 466001 P. R. China Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023 P. R. China;3. Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin, 150001 P. R. China;4. Oral Implant Center, Second Affiliated Hospital of Harbin Medical University, Harbin, 150086 P. R. China |
Abstract: | As a less O2-dependent photodynamic therapy (PDT), type I PDT is an effective approach to overcome the hypoxia-induced low efficiency against solid tumors. However, the commonly used metal-involved agents suffer from the long-term biosafety concern. Herein, a metal-free type I photosensitizer, N-doped carbon dots/mesoporous silica nanoparticles (NCDs/MSN, ≈40 nm) nanohybrid with peroxidase (POD)-like activity for synergistic PDT and enzyme-activity treatment, is developed on gram scale via a facile one-pot strategy through mixing carbon source and silica precursor with the assistance of template. Benefiting from the narrow bandgap (1.92 eV) and good charge separation capacity of NCDs/MSN, upon 640 nm light irradiation, the excited electrons in the conduction band can effectively generate O2•− by reduction of dissolved O2 via a one-electron transfer process even under hypoxic conditions, inducing apoptosis of tumor cells. Moreover, the photoinduced O2•− can partially transform into more toxic •OH through a two-electron reduction. Moreover, the POD-like activity of NCDs/MSN can catalyze the endogenous H2O2 to •OH in the tumor microenvironment, further synergistically ablating 4T1 tumor cells. Therefore, a mass production way to synthesize a novel metal-free type I photosensitizer with enzyme-mimic activity for synergistic treatment of hypoxic tumors is provided, which exhibits promising clinical translation prospects. |