An embryo of protocell membrane: The capsule of graphene oxide

1, Key Laboratory of Chemistry of Northwestern Plant Resources, Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000, P.R. China 2, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, P.R. China 3, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou, 730000, P.R. China 4, Radiochemistry Laboratory, Lanzhou University, Lanzhou, 730000, P.R. China 5, Department of Chemistry, State Key Lab of Molecular Engineering of Polymers, Shanghai Key Lab of Molecular Catalysis and Innovative Materials, and Collaborative Innovation Center of Chemistry for Energy Materials, Fudan University, Shanghai 200433, P. R. China. 6, School of Nuclear Science and Technology, Lanzhou University, Lanzhou, 730000, P.R. China 7, Key Laboratory of Grassland Agro-ecosystem, Ministry of Agriculture, School of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, P.R. China 8, Brookhaven National Laboratory Medical Department, Building 901, Room 106, Upton, NY 11973