Xiaohui Wang,Xiaofei Wei,Jinhua Liu,Dan He,Dandan Sun,Wei Yang,Yueying Jiao,Qi Cui
Traditional oxygen-dependent photodynamic therapy (PDT) faces formidable challenges owing to abnormal angiogenesis and insufficient oxygen supply in solid tumors. Herein, a multifunctional nanoplatform (HRP-DPBF-Zn) consisting of photosensitizer zinc (II) phthalocyanine (ZnPc), singlet oxygen ( 1 O 2 ) probe 1,3-diphenylisobenzofuran (DPBF), and hydrogen peroxide (H 2 O 2 ) catalyst horseradish peroxidase (HRP) is developed. Such HRP-DPBF-Zn nanosystems are expected to possess catalase-like capacity for catalyzing intracellular H 2 O 2 to produce oxygen (O 2 ). The enhanced O 2 content further facilitates the production of cytotoxic 1 O 2 by ZnPc under laser irradiation. DPBF loading endows the nanoplatform with the high 1 O 2 sensitivity, which can promote precise PDT with fluorescent 1 O 2 feedback. HRP-DPBF-Zn exhibits excellent biocompatibility, efficient 1 O 2 generation, high 1 O 2 sensitivity, favorable H 2 O 2 -to-O 2 decomposition, and superior fluorescence imaging properties. Both in vitro and in vivo experimental results confirm that such HRP-DPBF-Zn can accomplish highly specific and efficient PDT against hypoxic tumors, which shows great potential in tumor theranostics.
Single-atom dispersed catalysts (SACs) have gained considerable attention in organic contaminants remediation due to their superior reactivity and stability. However, the complex and costly synthesis processes limit their practical applications in environmental protection. Herein, a facile and cost-effective single-atom iron catalyst (Fe-SA/NC) anchored on nitrogen-doped porous carbon was first fabricated by using waste biomass as a carbon source. The Fe-SA/NC catalyst exhibited outstanding performance with a high turnover frequency of 1.72 min −1 toward antibiotics degradation via peroxymonosulfate activation . ECOSAR program and algae growth experiments demonstrated that the byproducts produced during the sulfamethoxazole degradation process were not detrimental to the aquatic environment. Radical quenching and electron paramagnetic resonance experiments revealed that Fe-SA/NC remarkably promoted 1 O 2 production in PMS-assisted reaction, and thus 1 O 2 contributed as much as 78.77% to sulfamethoxazole degradation. As indicated by experiment and density functional theory (DFT) calculations, FeN 2 O 2 configuration serves as the active site. DFT calculations further presented the most rational generation route of 1 O 2 as PMS→OH* →O* → 1 O 2 . We also designed Fe-SA/NC embedded spherical pellets for contaminants elimination at the device level. This study offers new insights into the synthesis of SACs from waste biomass and their practical application in environmental remediation.
危险品化学品经营许可证（带存储）