FITC-PEG-SH功能化Pt壳Pd纳米粒子的构建及其光响应性性能评估-UDP糖丨MOF丨金属有机框架丨聚集诱导发光丨推荐西安齐岳生物 -

Multifunctional phototherapy nanoagents for imaging-guided synergistic photothermal therapy (PTT) and photodynamic therapy (PDT) are highly desirable in the field of solid tumor therapy. Nevertheless, the tumor microenvironment (TME) inherently associated with hypoxia significantly hampers the photodynamic effect of these multifunctional nanoagents. Herein, Pd nanocubes coated with an ultrathin Pt shell were prepared and further conjugated with fluorescein labeled and thiol functionalized polyethylene glycol (FITC-PEG-SH) (denoted as Pd@Pt-PEG). The deposition of a Pt shell on Pd nanocubes not only enhances the photothermal performance, exhibiting excellent hyperthermia outcomes and impressive photothermal (PT) imaging quality, but also leads to the formation of singlet oxygen (1O2) induced by plasmonic excitation. In the meantime, the catalytic activity of the Pt layer is enhanced by electronic coupling and the plasmonic effect, which induces the decomposition of endogenous overexpressed hydrogen peroxide (H2O2) in tumors to generate O2 for conquering TME and augmenting 1O2 generation for efficacious tumor cell apoptosis. The modification of FITC-PEG-SH improves the biocompatibility and provides outstanding fluorescence (FL) imaging properties. Upon NIR laser irradiation, Pd@Pt-PEG allows in situ O2 generation and dual-mode imaging-guided synergistic PTT/PDT that effectively kills hypoxic tumor cells, which makes it a promising nanotherapeutic agent for enhanced tumor therapy.

用于成像引导的协同光热疗法（PTT）和光动力疗法（PDT）的多功能光疗纳米剂在实体瘤治疗领域受欢迎。然而，与缺氧固有相关的肿瘤微环境（TME）显著阻碍了这些多功能纳米药物的光动力效应。

在此，制备了涂有超薄Pt壳的Pd纳米立方体，并进一步与荧光素标记和巯基官能化的聚乙二醇（FITC-PEG-SH）（表示为Pd@Pt-PEG).Pt壳在Pd纳米立方体上的沉积不仅增强了光热性能，表现出优异的热疗效果和令人印象深刻的光热（Pt）成像质量，而且还导致等离子体激发诱导的单线态氧（1O2）的形成。

同时，Pt层的催化活性通过电子耦合和等离子体效应得到增强，这诱导了肿瘤中内源性过表达的过氧化氢（H2O2）的分解，产生O2以征服TME，并增加1O2的产生以实现有效的肿瘤细胞凋亡。FITC-PEG-SH的改性提高了生物相容性，并提供了出色的荧光（FL）成像性能。

在NIR激光照射下，Pd@Pt-PEG允许原位O2生成和双模成像引导的协同PTT/PDT，有效杀死缺氧肿瘤细胞，这使其成为增强肿瘤治疗的有前景的纳米治疗剂。