Constructing Activatable Photosensitizers Using Covalently Modified Mesoporous Silica
Yan Liu, Xiang Wang, Ben Wang, Zhenni Lu, Chunjiang WU, Zihao He, Libo Jiang, Peng Wei, Tao Yi
Abstract
The combination of photosensitizers (PSs) and nanomaterials is a widely used strategy to enhance PS efficacy and broaden their applicability. However, the current nanocarrier-based delivery strategies focus on conventional PSs, neglecting the critical issue of PS phototoxicity. In this study, DHUOCl-25, an activatable PS (aPS) activated by hypochlorous acid, is synthesized by combining a silicon source structure and an activation unit. DHUOCl-25 functions as a silica source for synthesizing activatable mesoporous silica nanostrctures (MSNs) using a standardized protocol, enabling the synthesis of aPS-covalently modified MSNs for a variety of biologic therapeutic applications. On one hand, the resulting nano-aPS maintains aPS functionality for antibacterial application by achieving synergistic antibacterial action via MB PDT and retained cetyltrimethylammonium bromide (CTAB) (antibacterial agent) (DHU-MSNs-2). On the other hand, the nano-aPS exhibits MSN properties for drug loading, facilitating the synergistic integration of photodynamic therapy with chemotherapy (DHU-MSNs-6) of tumors and demonstrating efficacy against the spinal metastases of lung cancer. These results validate this strategy for developing novel aPSs and expanding the application of aPSs and MSNs.