Loop Formation of Au Nanopaticles Adsorbed on Langmuir Monolayers

A hybrid monolayer of Au nanoparticles and dioctadecyl-dimethylammonium chloride (DODAC) was formed at the air–water interface. The Au nanoparticles were found to form loop structures. The loops were 0.1–1 (mu)m in size with a width of around 5 nm, and consisted of single particle strings. The loop formation depended on the density of the DODAC monolayers, but not on the size distribution of the particles.