Anisotropic Self-Assembly of Citrate-Coated Gold Nanoparticles on Fluidic Liposomes

The behavior of self-assembly processes of nanoscale particles on plasma membranes can reveal mechanisms of important biofunctions and/or intractable diseases. Self-assembly of citrate-coated gold nanoparticles (cAuNPs) on liposomes was investigated. The adsorbed cAuNPs were initially fixed on the liposome surfaces and did not self-assemble below the phospholipid phase transition temperature (Tm ). In contrast, anisotropic cAuNP self-assembly was observed upon heating of the composite above the Tm, where the phospholipids became fluid. The number of self-assembled NPs is conveniently controlled by the initial mixing ratio of cAuNPs and liposomes. Gold nanoparticle protecting agents strongly affected the self-assembly process on the fluidic membrane.