Reduced graphene oxide directed self-assembly of phospholipid monolayers in liquid and gel phases.
The response of cell membranes to the local physical environment significantly determines many biological processes and the practical applications of biomaterials. A better understanding of the dynamic assembly and environmental response of lipid membranes can help understand these processes and design novel nanomaterials for biomedical applications. The present work demonstrates the directed assembly of lipid monolayers, in both liquid and gel phases, on the surface of a monolayered reduced graphene oxide (rGO). The results from atomic force microscopy indicate that the hydrophobic aromatic plane and the defect holes due to reduction of GO sheets, along with the phase state and planar surface pressure of lipids, corporately determine the morphology and lateral structure of the assembled lipid monolayers. The DOPC molecules, in liquid phase, probably spread over the rGO surface with their tails associating closely with the hydrophobic aromatic plane, and accumulate to form circles of high area surrounding the defect holes on rGO sheets. However, the DPPC molecules, in gel phase, prefer to form a layer of continuous membrane covering the whole rGO sheet including defect holes. The strong association between rGO sheets and lipid tails further influences the melting behavior of lipids. This work reveals a dramatic effect of the local structure and surface property of rGO sheets on the substrate-directed assembly and subsequent phase behavior of the supported lipid membranes.
Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou, 215006, PR China; College of Physics, Optoelectronics and Energy, Soochow University, Suzhou, 215006, PR China.
Longfei
L
Rui
Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou, 215006, PR China; College of Physics, Optoelectronics and Energy, Soochow University, Suzhou, 215006, PR China.
Jiaojiao
J
Liu
Institute for Frontier Materials, Deakin University, Waurn Ponds, Vic, 3216, Australia.
Jingliang
J
Li
Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou, 215006, PR China; College of Physics, Optoelectronics and Energy, Soochow University, Suzhou, 215006, PR China.
Yuyan
Y
Weng
Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou, 215006, PR China; School of Electronic and Information Engineering, Soochow University, Suzhou, 215006, PR China.
Yujiang
Y
Dou
Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou, 215006, PR China; College of Physics, Optoelectronics and Energy, Soochow University, Suzhou, 215006, PR China. Electronic address: yuanbing@suda.edu.cn.
Bing
B
Yuan
Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou, 215006, PR China; College of Physics, Optoelectronics and Energy, Soochow University, Suzhou, 215006, PR China.
Kai
K
Yang
Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou, 215006, PR China; College of Physics, Optoelectronics and Energy, Soochow University, Suzhou, 215006, PR China; National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, 210093, PR China. Electronic address: myqiang@nju.edu.cn.
Yuqiang
Y
Ma
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000031:analogs & derivatives / Q000737:chemistry; D005782:Gels; D006108:Graphite / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D008567:Membranes, Artificial; D018625:Microscopy, Atomic Force; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D044367:Phase Transition; D010713:Phosphatidylcholines / Q000737:chemistry; D010714:Phosphatidylethanolamines / Q000737:chemistry; D010743:Phospholipids / Q000737:chemistry*; D011312:Pressure; D012235:Rhodamines / Q000737:chemistry; D013499:Surface Properties
D005782:Gels; D008567:Membranes, Artificial; D010087:Oxides; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010743:Phospholipids; D012235:Rhodamines; C046703:lissamine-rhodamine-phosphatidylethanolamine; D015060:1,2-Dipalmitoylphosphatidylcholine; C081581:colfosceril palmitate; D006108:Graphite; C017251:1,2-oleoylphosphatidylcholine
Phospholipid monolayer; Reduced graphene oxide; Self-assembly