Department of Chemical Engineering, University of Rhode Island , Kingston, Rhode Island 02881, United States.
Department of Mechanical Engineering, University of Utah , Salt Lake City, Utah 84112, United States.
Langmuir. 2017 May 30;33(21):5321-5327. doi: 10.1021/acs.langmuir.7b01273. Epub 2017 May 19.
Anionic liposomes coated with cationic polyelectrolyte poly-l-lysine (PLL), or layersomes, were used as soft, self-assembled templates for synthesizing gold nanoshells that absorb near-infrared radiation. The gold nanoshells were formed using two techniques: (a) direct reduction of tetrachloroauric acid on the layersomes and (b) the reduction of a tetrachloroauric acid/potassium carbonate "growth" solution on nanosized gold seeds bound to the surface of layersomes. The resulting structures were characterized by transmission and scanning electron microscopy and visible-near-infrared spectroscopy. Direct reduction produced discrete gold nanoparticles on the layersomes. The slower reduction from the growth solution on the gold seeds resulted in more complete shells. The absorption spectra of these suspensions were sensitive to the synthesis method. The morphology of the gold shells was tuned for absorption at biologically safe and tissue-penetrating NIR wavelengths, and laser irradiation at 810 nm produced significant heat. These gold-layersome nanoshells have the potential to be used for photothermal therapy, photothermally mediated drug delivery, and biomedical imaging.
带正电荷的聚电解质多聚赖氨酸（PLL）涂层的阴离子脂质体或层状囊泡可用作合成近红外辐射吸收金纳米壳的柔软自组装模板。金纳米壳是通过两种技术形成的：（a）在层状囊泡上直接还原四氯金酸，和（b）将四氯金酸/碳酸钾“生长”溶液还原到结合在层状囊泡表面的纳米金种子上。通过透射电子显微镜和扫描电子显微镜以及可见-近红外光谱对所得结构进行了表征。直接还原在层状囊泡上产生了离散的金纳米颗粒。从金种子上的生长溶液中较慢的还原导致了更完整的壳。这些悬浮液的吸收光谱对合成方法很敏感。这些金-层状囊泡纳米壳的形态可调节为吸收生物安全和组织穿透的近红外波长，并且在 810nm 的激光照射下会产生显著的热量。这些金-层状囊泡纳米壳具有用于光热疗法、光热介导药物输送和生物医学成像的潜力。
