Preliminary Data on the Nanoscale Chemical Characterization of the Inter-Crystalline Organic Matrix of a Calcium Carbonate Biomineral
Preliminary Data on the Nanoscale Chemical Characterization of the Inter-Crystalline Organic Matrix of a Calcium Carbonate Biomineral
复制标题
DOI：
10.3390/min8060223
复制
发表时间：
2018-06-01
期刊：
影响因子：
2.5
通讯作者：
Laiginhas, Fernando
中科院分区：
文献类型：
--
作者：
Perez-Huerta, Alberto;Laiginhas, Fernando
碳酸盐生物矿物的化学特征对于理解生物矿物的形成具有重要意义，并且在古气候学和古海洋学的应用中是地球科学的一个非常感兴趣的主题。一个突出的未知因素是有机基质的化学性质，特别是晶间部分的化学性质。在这里，我们使用原子探针层析成像（APT）对贻贝壳中的方解石中的矿物-有机界面进行纳米级化学表征。我们的研究结果表明，APT散装化学结果的质量是高度依赖于样品制备，但生物成因方解石的数据可以进行地球化学解释的信心。三维（3D）重建的方解石尖端标本显示存在的有机基质域，其特征在于阳离子的耗尽，但富集在氧和碳，并与至少1%的原子增加O-16相对于周围的矿物相。这是第一个相对的，在原位定量的碳酸盐生物矿物的晶间有机基质（IOM）的化学成分，为更好地了解生命的影响，代理校准，和这些生物碳酸盐的形成的影响。总的来说，我们的研究结果表明，纳米级表征的生物矿物和它们的非生物对应物，以进一步推进我们的化学理解的潜力。
Chemical signatures of carbonate biominerals are important for understanding biomineral formation, and are a subject of great interest in geosciences for applications in paleoclimatology and paleoceanography. A prominent unknown factor is the chemistry of organic matrices, in particular that of the inter-crystalline fraction. Here, we use atom probe tomography (APT) for the nanoscale chemical characterization of the mineral-organic interface in calcite from mussel shells. Our findings indicate that the quality of APT bulk chemistry results is highly dependent on sample preparation, yet data on biogenic calcite could be geochemically interpreted with confidence. Three-dimensional (3D) reconstructions of calcite tip specimens show the presence of organic matrix domains, characterized by the depletion of cations but enrichment in oxygen and carbon, and with at least 1% atomic increase in O-16 relative to the surrounding mineral phase. This is the first relative, in-situ quantification of the chemical composition of the inter-crystalline organic matrix (IOM) for a carbonate biomineral, with implications for a better understanding of vital effects, proxy calibration, and the formation of these biocarbonates. Overall, our findings demonstrate the potential of nanoscale characterization of biominerals and their abiogenic counterparts to further advance our understanding of their chemistry.