Fractal Growth of Crystalline Phospholipid Domains in Monomolecular Layers

Abstract
Self-similar structures of single-crystalline domains in lipid monolayers at the air-water interface are observed after a stepwise increase of the surface pressure. It is shown that these fractal structures with Hausdorff dimensions of d1.5 anneal because of the influence of edge tension on time scales of minutes. The results can be understood within the framework of diffusion-limited aggregation taking into account constitutional supercooling due to different miscibilities for impurities in solid and in fluid lipid phases.