Interactions of Graphene Oxide with Model Cell Membranes: Probing Nanoparticle Attachment and Lipid Bilayer Disruption
Interactions of Graphene Oxide with Model Cell Membranes: Probing Nanoparticle Attachment and Lipid Bilayer Disruption
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DOI：
10.1021/acs.langmuir.5b02414
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发表时间：
2015-11-10
期刊：
影响因子：
3.9
通讯作者：
Chen, Kai Loon
中科院分区：
文献类型：
--
作者：
Liu, Xitong;Chen, Kai Loon
随着氧化石墨烯（graphene oxide，GO）在各个领域应用的快速增长，GO对细菌和哺乳动物细胞的毒性最近引起了广泛的研究关注。虽然已经提出了GO的细胞毒性的几种机制，但预计GO与细胞膜的附着是这些机制之前的关键初始过程。在这项研究中，我们调查的倾向GO附着到和破坏模型细胞膜使用支持的脂质双层（SLB）和支持的囊泡层（SVL），由两性离子的1，2-二油酰基-sn-甘油-3-磷酸胆碱（DOPC）。GO在SLB上的沉积动力学使用具有耗散监测的石英晶体微天平测定，并且观察到随着电解质（NaCl和CaCl 2）浓度的增加而增加，表明GO附着到SLB是由静电相互作用控制的。在升高的电解质浓度下测量的GO沉积动力学低于传质限制动力学，这可能是由于GO和SLB之间存在水合力。在GO附着到用荧光染料包封的支持的囊泡后，检测到染料泄漏，从而表明脂质囊泡被破坏。当终止SVL暴露于GO悬浮液时，染料的泄漏显著降低，表明脂质双层上的孔具有自修复能力。
With the rapid growth in the application of graphene oxide (GO) in diverse fields, the toxicity of GO toward bacterial and mammalian cells has recently attracted extensive research attention. While several mechanisms have been proposed for the cytotoxicity of GO, the attachment of GO to cell membranes is expected to be the key initial process that precedes these mechanisms. In this study, we investigate the propensity for GO to attach to and disrupt model cell membranes using supported lipid bilayers (SLBs) and supported vesicular layers (SVLs) that are composed of zwitterionic 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). The deposition kinetics of GO on SLBs were determined using quartz crystal microbalance with dissipation monitoring and were observed to increase with increasing electrolyte (NaCl and CaCl2) concentrations, indicating that GO attachment to SLBs was controlled by electrostatic interactions. The GO deposition kinetics measured at elevated electrolyte concentrations were lower than mass-transfer-limited kinetics, likely due to the presence of hydration forces between GO and SLBs. Upon the attachment of GO to supported vesicles that were encapsulated with a fluorescent dye, dye leakage was detected, thus indicating that the lipid vesicles were disrupted. When the exposure of the SVL to the GO suspension was terminated, the leakage of dye decreased significantly, demonstrating that the pores on the lipid bilayers have a self-healing ability.