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Nacre, found in mollusk shells, exhibits several interesting mechanical properties. It is composed of small individual platelets of calcium carbonate (aragonite) interwoven in a matrix of organic materials. Each platelet is composed of smaller platelets that are 500 nm thick. This hierarchical brick and mortar layout gives nacre a 3000 times higher fracture toughness than geological aragonite. Understanding the interaction between the organic layer and the aragonite platelets as well as the particle-particle interaction in nacre is important to the further development of biomimetic materials.
One hypothesis suggests that nacre forms from amorphous calcium carbonate (ACC) particles that nucleate on an organic layer. To understand the role of ACC in the nacre formation process, ACC nanoparticles were synthesized in vitro for deposition by convective assembly. In order to create a monolayer of ACC nanoparticles by convective assembly the system must be mono-dispersed in a volatile solvent. Various surfactants were used to create a mono-dispersed system of ACC nanoparticles in water.