Interaction of Graphene Oxide with Bacterial Cell Membranes: Insights from Force Spectroscopy
Interaction of Graphene Oxide with Bacterial Cell Membranes: Insights from Force Spectroscopy
复制标题
DOI：
10.1021/acs.estlett.5b00066
复制
发表时间：
2015-04-01
影响因子：
10.9
通讯作者：
Elimelech, Menachem
中科院分区：
文献类型：
--
作者：
Castrillon, Santiago Romero-Vargas;Perreault, Francois;Elimelech, Menachem
理解氧化石墨烯（GO）与生物膜的相互作用对于评估GO对健康和环境的影响、其杀菌活性以及推进基于石墨烯的生物和环境应用至关重要。为了理解石墨烯诱导的细菌失活，我们利用原子力显微镜（AFM）研究了GO与细菌（大肠杆菌）细胞膜的相互作用。为此，我们设计了一种聚多巴胺辅助的实验方案，用GO纳米片对AFM探针进行功能化，并使用基于AFM的力谱来测量细胞膜与GO的相互作用力。我们的结果表明，GO与细胞的相互作用主要是排斥的，在探针拉离时仅测量到零星的粘附力，我们将其归因于脂多糖桥接。我们提供了GO对谷胱甘肽进行无细胞氧化的证据，强调了氧化途径在GO介导的细菌细胞失活中的作用。我们的力谱结果表明，物理化学相互作用并非GO对细菌的主要作用方式的基础。
Understanding the interactions of graphene oxide (GO) with biological membranes is crucial for the evaluation of GO's health and environmental impacts, its bactericidal activity, and to advance graphene-based biological and environmental applications. In an effort to understand graphene-induced bacterial inactivation, we studied the interaction of GO with bacterial (Escherichia col cell membranes using atomic force microscopy (AFM). Toward this goal, we devised a polydopamine-assisted experimental protocol to functionalize an AFM probe with GO nanosheets, and used AFM-based force spectroscopy to measure cell membrane GO interaction forces. Our results show that GO cell interactions are predominantly repulsive, with only sporadic adhesion forces being measured upon probe pull-off, which we attribute to lipopolysaccharide bridging. We provide evidence of the acellular oxidation of glutathione by GO, underscoring the role of oxidative pathways in GO-mediated bacterial cell inactivation. Our force spectroscopy results suggest that physicochemical interactions do not underlie the primary mode of action of GO in bacteria.