pH-responsive nanovesicles capable of remodeling the tumor microenvironment enable activatable near-infrared-II fluorescence image-guided enhanced radiotherapy

作者：Lin Zhao, Mengzhen Wang, Yang Sun, Jinpeng Xu, Qinrui Fu, Wenjing Xiao · 发表于：Materials Today Bio · 年份：2025 · DOI：10.1016/j.mtbio.2025.101725 · 被引用次数：4 · 研究领域：Nanoplatforms for cancer theranostics、Extracellular vesicles in disease、Advanced Nanomaterials in Catalysis

Traditional radiotherapy (RT) lacks the precision to distinguish between tumor and normal tissues, leading to inevitable X-ray-induced side effects in patients. Therefore, it is crucial to develop integrated imaging and therapeutic modalities that can reduce side effects on surrounding healthy tissues while enhancing susceptibility to tumor tissues. In this study, we developed a pH-responsive nanodrug (AuNRs-Mn 3 O 4 -Ag 2 S Ve) by self-assembling the second near-infrared (NIR-II, 950–1700 nm) fluorescent probe Ag 2 S quantum dots (QDs), multifunctional nanozyme Mn 3 O 4 nanoparticles (NPs), and radiosensitizer gold nanorods (AuNRs) into a single nanoplatform via an emulsion process. This nanodrug enables precise tumor localization for accurately guided RT and multi-angle sensitization of RT. Upon intravenous administration, the nanodrug disintegrates in the tumor area due to the pH-sensitive polymer P4VP, releasing Ag 2 S QDs which are specifically activated by the acidic environment, thereby “turning on” the NIR-II fluorescence signal. The optimal timing of the NIR-II fluorescence signal within the tumor region after intravenous injection was investigated, providing a reference for guided RT. In vitro and in vivo experiments confirmed the efficient enhancement of tumor radiosensitization by AuNRs and Mn 3 O 4 NPs. The specific imaging modality that transitions the fluorescence signal from “off” to “on” has been successfully implemented, addressing the limitations of convent...