Demineralization of Biominerals

The presence of apatite nanoparticles in mature bone and enamel may also be due to the stabilization of some nanosized particles during the formation process in the fluctuating biological milieu (note the biological milieu is extremely conservative = homeostasis ) [37]. Demineralization studies of bone and enamel have shown that the nanostructured apatite particles can be extremely stable in the solutions. These phenomena agree with the proposal that nanoparticles may act as the building blocks of the biomaterials, and thus can be considered as basic units [38, 79], The results also showed that the biomaterials become insensitive to dissolution at the nanoscale level. 

Another excellent example was also seen in studies of caries lesion formation. Enamel surfaces remain undissolved in water (pH = 5.5-5.8), in spite of any undersaturation consequently, caries (dissolution) will only be induced at localized sites where the bacteria have produced strong acidic conditions. The mineral crystallites can be stabilized in the fluctuating physiological fluids. Such nanodissolution behavior of nanoparticles may also be significant with regards to solvent stability and reactivity in working nanoparticle-based structures and sensors. 

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