Figure 7.

Templating of diatom cell wall structure by the physical-chemical properties of long-chain polyamines within the silica-deposition vesicle in the phase separation model. (a)–(d) are models and (e)–(h) are scanning electron micrographs of the silaffin-free diatom C. wailesii valves at different stages of growth. (a) A monolayer of LCPA droplets in a hexagonal arrangement. (b) and (c): Stepwise segregation into smaller droplets provides new locations for silica precipitation to the final dispersion into 50-nm droplets. Silica precipitation takes place within the water phase (white areas). Reproduced with permission from [54].