School of Materials Science and Engineering, The University of New South Wales , Sydney, New South Wales 2052, Australia.
Department of Chemical Engineering, Monash University , Clayton, Victoria 3800, Australia.
ACS Appl Mater Interfaces. 2015 Nov 25;7(46):25658-68. doi: 10.1021/acsami.5b07975. Epub 2015 Nov 13.
Gold nanorods and their core-shell nanocomposites have been widely studied because of their well-defined anisotropy and unique optical properties and applications. This study demonstrates a facile hydrothermal synthesis strategy for generating carbon coating on gold nanorods (AuNRs@C) under mild conditions (<200 °C), where the carbon shell is composed of polymerized sugar molecules (glucose). The structure and composition of the produced core-shell nanocomposites were characterized using advanced microscopic and spectroscopic techniques. The functional properties, particularly the photothermal and biocompatibility properties of the produced AuNRs@C, were quantified to assess their potential in photothermal hyperthermia. These AuNRs@C were tested in vitro (under representative treatment conditions) using near-infrared (NIR) light irradiation. It was found that the AuNRs produced here exhibit exemplary heat generation capability. Temperature changes of 10.5, 9, and 8 °C for AuNRs@C were observed with carbon shell thicknesses of 10, 17, and 25 nm, respectively, at a concentration of 50 μM, after 600 s of irradiation with a laser power of 0.17 W/cm(2). In addition, the synthesized AuNRs@C also exhibit good biocompatibility toward two soft tissue sarcoma cell lines (HT1080, a fibrosarcoma; and GCT, a fibrous histiocytoma). The cell viability study shows that AuNRs@C (at a concentration of <0.1 mg/mL) core-shell particles induce significantly lower cytotoxicity on both HT1080 and GCT cell lines, as compared with cetyltrimethylammonium bromide (CTAB)-capped AuNRs. Furthermore, similar to PEG-modified AuNRs, they are also safe to both HT1080 and GCT cell lines. This biocompatibility results from a surface full of -OH or -COH groups, which are suitable for linking and are nontoxic Therefore, the AuNRs@C represent a viable alternative to PEG-coated AuNRs for facile synthesis and improved photothermal conversion. Overall, these findings open up a new class of carbon-coated nanostructures that are biocompatible and could potentially be employed in a wide range of biomedical applications.
金纳米棒及其核壳纳米复合材料由于其各向异性和独特的光学性质及应用而得到了广泛的研究。本研究展示了一种在温和条件（<200°C）下生成金纳米棒（AuNRs@C）碳壳的简便水热合成策略，其中碳壳由聚合糖分子（葡萄糖）组成。采用先进的微观和光谱技术对所生成的核壳纳米复合材料的结构和组成进行了表征。对所生成的 AuNRs@C 的功能特性，特别是光热和生物相容性特性进行了定量评估，以评估其在光热高热治疗中的应用潜力。这些 AuNRs@C 在体外（在代表性的处理条件下）使用近红外（NIR）光照射进行了测试。结果发现，这里生成的 AuNRs 表现出出色的发热能力。在浓度为 50 μM 时，当用激光功率为 0.17 W/cm(2) 照射 600 s 后，分别具有 10、17 和 25 nm 碳壳厚度的 AuNRs@C 观察到 10.5、9 和 8°C 的温度变化。此外，所合成的 AuNRs@C 对两种软组织肉瘤细胞系（纤维肉瘤 HT1080 和纤维组织细胞瘤 GCT）也表现出良好的生物相容性。细胞活力研究表明，与十六烷基三甲基溴化铵（CTAB）封端的 AuNRs 相比，浓度<0.1 mg/mL 的 AuNRs@C 核壳颗粒对 HT1080 和 GCT 细胞系的细胞毒性明显更低。此外，与聚乙二醇（PEG）修饰的 AuNRs 一样，它们对 HT1080 和 GCT 细胞系也安全。这种生物相容性源于表面充满了 -OH 或 -COH 基团，这些基团适合连接且无毒。因此，AuNRs@C 是一种替代聚乙二醇（PEG）包覆的 AuNRs 的可行选择，具有简便的合成和提高的光热转换效率。总体而言，这些发现开辟了一类新的生物相容性碳包覆纳米结构，它们可能在广泛的生物医学应用中得到应用。
