Biominerals description

Looking at the literature in the field of biomineralization, one notices, that the majority of articles is descriptive in nature. On the basis of electron micrographs or thin section studies, the intricate relationships between mineral phase and organic matrix are investigated. Other papers deal with the chemical composition of the mineralized tissue and the minerals. Only a few authors address themselves to the question of metal ion transport mechanisms in cellular systems and the solid state principles involved in mineral deposition on organic substrates. All three sets of information, however, are essential to understand calcification processes. It appears, therefore, that information on the functionality of metal ions in living systems and their role in mineral deposition are particularly desired in this area of research. 

In this section, some NMR techniques which have been applied to the study of biomineralization are introduced. The NMR techniques discussed below are all under the condition of magic-angle spinning (MAS). The discussion is largely descriptive and qualitative. Readers who are interested in a more rigorous exposition of the NMR theories are referred to the original literature. The implications of the NMR results in biomineralization are discussed in other sections. 

Prior to the definitive X-ray powder diffraction characterization of HZ, the true structure of the aggregate remained elusive because of its limited solubility. HZ was soluble only in NaOH, which completely degraded the structure and prevented any attempt to determine the intramolecular atomic interactions. The insolubility of the product rendered useless many standard experimental methods for the characterization of bioinorganic systems. This aspect of the biomineral s identification undoubtedly contributed to Ridley s description of HZ as a black insoluble mass of material that can be soul-destroying to work with (31). 

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