Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, School of Chemistry and Chemical Engineering, Tianjin University of Technology , Tianjin 300384, P. R. China.
ACS Appl Mater Interfaces. 2017 Aug 16;9(32):26731-26739. doi: 10.1021/acsami.7b07768. Epub 2017 Aug 2.
Photodynamic therapy (PDT) is an auspicious strategy for cancer therapy by yielding reactive oxygen species (ROS) under light irradiation. Here, we have developed near-infrared (NIR) triggered polymer encapsulated upconversion nanoparticles (UCNPs) based on aggregation-induced emission (AIE) characteristics and mitochondria target ability for PDT. The coated AIE polymer as a photosensitizer can be photoactivated by the up-converted energy of UCNPs upon 980 nm laser irradiation, which could generate ROS efficiently in mitochondria and induce cell apoptosis. Moreover, a "sheddable" poly(ethylene glycol) (PEG) layer was easily conjugated at the surface of NPs. The pH-responsive PEG layer shields the surface positive charges and shows stronger protein-resistance ability. In the acidic tumor environment, PEGylated NPs lose the PEG layer and show the mitochondria-targeting ability by responding to tumor acidity. A cytotoxicity study indicated that these NPs have good biocompatibility in the dark but exert severe cytotoxicity to cancer cells, with only 10% cell viability, upon being irradiated with an NIR laser. The AIE nanoparticles are a good candidate for effective mitochondria targeting photosensitizer for PDT.
光动力疗法（PDT）是一种很有前途的癌症治疗策略，它可以在光照射下产生活性氧（ROS）。在这里，我们开发了基于聚集诱导发射（AIE）特性和线粒体靶向能力的近红外（NIR）触发聚合物封装上转换纳米粒子（UCNPs）用于 PDT。包覆的 AIE 聚合物作为光敏剂，可以在 980nm 激光照射下被 UCNPs 的上转换能量激活，从而在线粒体中有效产生 ROS 并诱导细胞凋亡。此外，很容易在 NPs 表面接枝一层“可脱落”的聚乙二醇（PEG）。pH 响应性 PEG 层屏蔽了表面正电荷，并显示出更强的抗蛋白能力。在酸性肿瘤环境中，PEG 化 NPs 失去 PEG 层，并通过响应肿瘤酸度显示出线粒体靶向能力。细胞毒性研究表明，这些 NPs 在黑暗中具有良好的生物相容性，但在近红外激光照射下，对癌细胞表现出严重的细胞毒性，仅有 10%的细胞存活。AIE 纳米粒子是一种很有前途的用于 PDT 的有效线粒体靶向光敏剂。
