Department of Animal Biotechnology, Konkuk University, Seoul, South Korea.
Int J Nanomedicine. 2013;8:1015-27. doi: 10.2147/IJN.S42047. Epub 2013 Mar 10.
This paper describes an environmentally friendly ("green") approach for the synthesis of soluble graphene using Bacillus marisflavi biomass as a reducing and stabilizing agent under mild conditions in aqueous solution. In addition, the study reported here investigated the cytotoxicity effects of graphene oxide (GO) and bacterially reduced graphene oxide (B-rGO) on the inhibition of cell viability, reactive oxygen species (ROS) generation, and membrane integrity in human breast cancer cells.
The reduction of GO was characterized by ultraviolet-visible spectroscopy. Size distribution was analyzed by dynamic light scattering. Further, X-ray diffraction and high-resolution scanning electron microscopy were used to investigate the crystallinity of graphene and the morphologies of prepared graphene, respectively. The formation of defects further supports the bio-functionalization of graphene, as indicated in the Raman spectrum of B-rGO. Surface morphology and the thickness of the GO and B-rGO were analyzed using atomic force microscopy, while the biocompatibility of GO and B-rGO were investigated using WST-8 assays on MCF-7 cells. Finally, cellular toxicity was evaluated by ROS generation and membrane integrity assays.
In this study, we demonstrated an environmentally friendly, cost-effective, and simple method for the preparation of water-soluble graphene using bacterial biomass. This reduction method avoids the use of toxic reagents such as hydrazine and hydrazine hydrate. The synthesized soluble graphene was confirmed using various analytical techniques. Our results suggest that both GO and B-rGO exhibit toxicity to MCF-7 cells in a dose-dependent manner, with a dose > 60 μg/mL exhibiting obvious cytotoxicity effects, such as decreasing cell viability, increasing ROS generation, and releasing of lactate dehydrogenase.
We developed a green and a simple approach to produce graphene using bacterial biomass as a reducing and stabilizing agent. The proposed approach confers B-rGO with great potential for various biological and biomedical applications.
本文描述了一种环保（“绿色”）的方法，即在水溶液中，利用海栖热袍菌生物质作为还原剂和稳定剂，在温和条件下合成可溶性石墨烯。此外，本研究还考察了氧化石墨烯（GO）和细菌还原氧化石墨烯（B-rGO）对人乳腺癌细胞活力抑制、活性氧（ROS）生成和膜完整性的细胞毒性作用。
通过紫外-可见光谱对 GO 的还原进行了表征。通过动态光散射分析了粒径分布。进一步，使用 X 射线衍射和高分辨率扫描电子显微镜分别研究了石墨烯的结晶度和制备石墨烯的形貌。拉曼光谱进一步表明石墨烯的生物功能化，出现了缺陷。原子力显微镜分析了 GO 和 B-rGO 的表面形貌和厚度，WST-8 法检测了 GO 和 B-rGO 的细胞生物相容性。最后，通过 ROS 生成和膜完整性测定评估细胞毒性。
本研究采用细菌生物质，展示了一种环保、经济且简单的制备水溶性石墨烯的方法。这种还原方法避免了使用肼和水合肼等有毒试剂。通过各种分析技术证实了合成的可溶性石墨烯。我们的结果表明，GO 和 B-rGO 对 MCF-7 细胞均具有剂量依赖性毒性，剂量>60μg/ml 时表现出明显的细胞毒性作用，如细胞活力降低、ROS 生成增加和乳酸脱氢酶释放。
我们开发了一种使用细菌生物质作为还原剂和稳定剂来生产石墨烯的绿色简单方法。所提出的方法使 B-rGO 具有在各种生物和生物医学应用中的巨大潜力。
