[2Gp01-04] Soft matter/Biomaterial (SO/BI)

[2Gp04] Localization of lipid domains in supported lipid bilayers induced by graphene oxide

*Ryugo Tero¹ (1. Toyohashi University of Technology)

We investigated the distribution of the gel-phase domains and the liquid crystalline (L_α) phase regions in a binary supported lipid bilayer (SLB) comprising dioleoylphosphatidylcholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC) on thermally oxidized SiO₂/Si substrates with graphene oxide (GO) flakes. Fluorescence microscopy and atomic force microscopy observations revealed that the gel-phase domains in the DOPC+DPPC-SLB were localized on GO, leaving the L_α phase region on the bare SiO2 surface around the GO flakes. The gel phase domain was condensed on GO more effectively at the lower cooling rate. We attribute the domain localization to the preferential nucleation on GO at the initial step of the domain growth, based on the dependence of the localization efficiency on the cooling rate. This mechanism was consistent with the results of the ternary SLB comprising PC, sphingomyelin, and cholesterol on GO/SiO2/Si.