Two competitive nucleation mechanisms of calcium carbonate biomineralization in response to surface functionality in low calcium ion concentration solution.
Two competitive nucleation mechanisms of calcium carbonate biomineralization in response to surface functionality in low calcium ion concentration solution.
复制标题
低钙离子浓度溶液中碳酸钙生物矿化响应表面功能的两种竞争成核机制
DOI：
10.1093/rb/rbv010
复制
发表时间：
2015-09
影响因子：
6.7
通讯作者：
Cui F
中科院分区：
文献类型：
--
作者：
Deng H;Wang S;Wang X;Du C;Shen X;Wang Y;Cui F
利用4种末端分别带有-COOH、-OH、-NH 2和-CH 3官能团的自组装单分子膜表面，研究了低钙离子浓度下碳酸钙（CaCO 3）的生物矿化过程，并进一步探讨了12 h内碳酸钙成核和初始结晶的机理。在−COOH表面上，成核主要通过离子聚集机制进行，但也可能涉及预成核离子簇。然而，在−OH和− NH 2表面上，成核通过碳酸钙簇形成，这些簇在溶液中聚集，然后吸附在表面上，随后无定形碳酸钙（ACC）成核。此外，带强负电荷的−COOH表面促进了方解石的直接形成，−OH和− NH 2表面决定了具有优选晶体取向的球霰石的形成。在− CH 3表面上既没有观察到ACC，也没有观察到结晶CaCO 3。我们的研究结果提出了一个有价值的模型，以了解在自然系统中的碳酸钙生物矿化途径，其中功能团组成在碳酸钙结晶过程中起着决定性的作用。
Four self-assembled monolayer surfaces terminated with –COOH, –OH, –NH2 and –CH3 functional groups are used to direct the biomineralization processes of calcium carbonate (CaCO3) in low Ca2+ concentration, and the mechanism of nucleation and initial crystallization within 12 h was further explored. On −COOH surface, nucleation occurs mainly via ion aggregation mechanism while prenucleation ions clusters may be also involved. On −OH and −NH2 surfaces, however, nucleation forms via calcium carbonate clusters, which aggregate in solution and then are adsorbed onto surfaces following with nucleation of amorphous calcium carbonate (ACC). Furthermore, strongly negative-charged −COOH surface facilitates the direct formation of calcites, and the −OH and −NH2 surfaces determine the formation of vaterites with preferred crystalline orientations. Neither ACC nor crystalline CaCO3 is observed on −CH3 surface. Our findings present a valuable model to understand the CaCO3 biomineralization pathway in natural system where functional groups composition plays a determining role during calcium carbonate crystallization.