Yan Dong, Zhao Haiyan, Pei Jiayun, Wu Xin, Liu Yue
Department of Mechanical Engineering, Tsinghua University, Beijing 100084, PR China; State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, PR China.
Department of Mechanical Engineering, Tsinghua University, Beijing 100084, PR China; State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, PR China.
Mater Sci Eng C Mater Biol Appl. 2017 Mar 1;72:659-666. doi: 10.1016/j.msec.2016.11.130. Epub 2016 Dec 5.
Novel two-dimensional materials with a layered structure are of special interest for a variety of promising applications. In current research, the nanostructured graphene oxide-FeO composite (GO-FeO) was firstly obtained via a carefully elaborated approach of vacuum freeze-drying. The scanning electron microscopy (SEM) and transmission electron microscope (TEM) images revealed that α-FeO nanoparticles loaded well on the surfaces of graphene. A series of characterization were performed to further elucidate the as-obtained nanomaterial's physicochemical properties. These results suggested the current route could be further extended to obtain the other kinds of two-dimensional materials based composites. For the sake of extending the potential application of herein achieved graphene composites, its cytotoxicity assessment on HeLa cells was systematically investigated. CCK-8 assay in HeLa cells treated by GO-FeO showed dose- (1-100μg/ml) and time- (24-48h) dependent cytotoxicity, which was comparable to that of GO. The excess generation of intracellular reactive oxygen species (ROS) induced by these nanomaterials was responsible for the cytotoxicity. TEM analysis vividly illustrated GO-FeO internalized by HeLa cells in endomembrane compartments such as lysosomes, and degraded through autophagic pathway. The detrimental biological consequence accompanied by cell internalization was limited. Based on the above results, it expected to render useful information for the development of new and popular strategies to design graphene-based composites, as well as deep insights into the mechanism of graphene-based composites cytotoxicity for further potential application.
具有层状结构的新型二维材料在各种有前景的应用中具有特殊的吸引力。在当前的研究中，首先通过精心设计的真空冷冻干燥方法获得了纳米结构的氧化石墨烯 - 氧化亚铁复合材料（GO-FeO）。扫描电子显微镜（SEM）和透射电子显微镜（TEM）图像显示，α-FeO纳米颗粒很好地负载在石墨烯表面。进行了一系列表征以进一步阐明所获得的纳米材料的物理化学性质。这些结果表明，当前的路线可以进一步扩展以获得其他种类的二维材料基复合材料。为了扩展本文所制备的石墨烯复合材料的潜在应用，系统地研究了其对HeLa细胞的细胞毒性评估。用GO-FeO处理的HeLa细胞中的CCK-8测定显示出剂量（1-100μg/ml）和时间（24-48小时）依赖性细胞毒性，这与GO的细胞毒性相当。这些纳米材料诱导的细胞内活性氧（ROS）的过量产生是细胞毒性的原因。TEM分析生动地说明了GO-FeO被HeLa细胞内化到内膜隔室如溶酶体中，并通过自噬途径降解。细胞内化伴随的有害生物学后果是有限的。基于上述结果，可以为设计基于石墨烯的复合材料的新的流行策略的开发提供有用的信息，以及对基于石墨烯的复合材料细胞毒性机制的深入了解，以用于进一步的潜在应用。
