Liu Siyang, Yuan Ye, Yang Yingkun, Liu Zhihe, Yin Shengyan, Qin Weiping, Wu Changfeng
College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
J Mater Chem B. 2017 Nov 7;5(41):8169-8177. doi: 10.1039/c7tb01968h. Epub 2017 Oct 11.
The energy transfer from upconversion nanoparticles (UCNPs) to photosensitizers has been widely used for generating reactive oxygen species (ROS) in photodynamic therapy (PDT) by near infrared (NIR) excitation. However, the poor spectral overlap of lanthanide ions and conventional photosensitizers leads to low PDT efficiency. In this study, we construct a multilayered upconversion nanoplatform with dual photosensitizers to efficiently use the UV and visible upconversion emissions in NIR-responsive PDT. The nanoplatform consists of three functional layers, which are the upconversion nanoparticle as a core, and light-sensitive conjugated polymer and apo-transferrin-titanocene (Tf@Tc) as shells. Under NIR irradiation, apparent energy transfer occurs from the core to the polymer and Tc components in the shell, producing reactive oxygen species and free radicals for cancer cell killing. In vitro cellular assays show the synergistic therapeutic effect of the conjugated polymer and Tc as photosensitizers. In vivo animal studies show that tumor growth is significantly inhibited in the mice receiving the theranostic platform and NIR irradiation. Based on these observations, the multilayered upconversion nanocomposites can find potential applications in NIR-mediated anti-tumor therapy.
在上转换纳米粒子（UCNPs）与光敏剂之间的能量转移已被广泛用于通过近红外（NIR）激发在光动力疗法（PDT）中产生活性氧（ROS）。然而，镧系离子与传统光敏剂的光谱重叠较差导致PDT效率较低。在本研究中，我们构建了一种具有双光敏剂的多层上转换纳米平台，以在近红外响应的光动力疗法中有效利用紫外和可见上转换发射。该纳米平台由三个功能层组成，即以一个上转换纳米粒子为核心，以及作为壳层的光敏共轭聚合物和脱铁转铁蛋白-钛茂（Tf@Tc）。在近红外照射下，明显的能量从核心转移到壳层中的聚合物和Tc组分，产生活性氧和自由基以杀死癌细胞。体外细胞实验表明共轭聚合物和Tc作为光敏剂具有协同治疗效果。体内动物研究表明，接受该诊疗平台和近红外照射的小鼠体内肿瘤生长受到显著抑制。基于这些观察结果，多层上转换纳米复合材料在近红外介导的抗肿瘤治疗中具有潜在应用。
