Atomistic View of Mineral-adsorbate Interface

Apatite is an important biomineral, which constitutes the endoskeleton (bones and teeth) in vertebrates including humans. The interaction between the apatite surface and biological environment plays a key role in biomineralization. To understand the interaction between apatite and inorganic species, atomic scale information of the apatite surface and the apatite-biomolecular interface is required. In this work, the structure of fluorapatite (100) surface was first investigated in dry environmental conditions using Grazing Incidence X-ray Diffraction (GIXRD). Further, to understand the apatite-biomolecular interface, experiments were performed under humid and completely hydrated conditions, which were then followed by apatite-aqueous glycine interface study. Measurement and analyses of specular and non- specular crystal truncation rods in all cases provided information about the surface structure of the mineral and sites of adsorption at the atomic scale. Simulation studies supported the experimental results.