Gold nanohexapods represent a novel class of optically tunable nanostructures consisting of an octahedral core and six arms grown on its vertices. By controlling the length of the arms, their localized surface plasmon resonance peaks could be tuned from the visible to the near-infrared region for deep penetration of light into soft tissues. Herein we compare the in vitro and in vivo capabilities of Au nanohexapods as photothermal transducers for theranostic applications by benchmarking against those of Au nanorods and nanocages. While all these Au nanostructures could absorb and convert near-infrared light into heat, Au nanohexapods exhibited the highest cellular uptake and the lowest cytotoxicity in vitro for both the as-prepared and PEGylated nanostructures. In vivo pharmacokinetic studies showed that the PEGylated Au nanohexapods had significant blood circulation and tumor accumulation in a mouse breast cancer model. Following photothermal treatment, substantial heat was produced in situ and the tumor metabolism was greatly reduced for all these Au nanostructures, as determined with ^(18)F-flourodeoxyglucose positron emission tomography/computed tomography (^(18)F-FDG PET/CT). Combined together, we can conclude that Au nanohexapods are promising candidates for cancer theranostics in terms of both photothermal destruction and contrast-enhanced diagnosis.
展开▼
机译:金纳米六足动物代表了一类新型的光学可调纳米结构,包括八面体核心和在其顶点上生长的六个臂。通过控制臂的长度,可以将其局部表面等离振子共振峰从可见光调整到近红外区域,以使光深入穿透软组织。在本文中,我们通过对比金纳米棒和纳米笼的基准,比较了金纳米六足动物作为光热换能器用于治疗诊断应用的体外和体内能力。尽管所有这些金纳米结构都可以吸收近红外光并将其转换成热量,但金纳米六足动物在体外和制备的聚乙二醇化纳米结构中均表现出最高的细胞吸收和最低的细胞毒性。体内药代动力学研究表明,聚乙二醇化金纳米六足动物在小鼠乳腺癌模型中具有明显的血液循环和肿瘤蓄积。经光热处理后,所有这些Au纳米结构的原位产生大量热量,并且通过^(18)F-氟脱氧葡萄糖正电子发射断层扫描/计算机断层扫描(^(18)F-FDG PET / CT确定),所有这些Au纳米结构的肿瘤代谢均大大降低)。结合在一起,我们可以得出结论,就光热破坏和增强对比的诊断而言,金纳米六足动物是癌症治疗学的有希望的候选者。
展开▼