Pouget Emilie M, Bomans Paul H H, Goos Jeroen A C M, Frederik Peter M, de With Gijsbertus, Sommerdijk Nico A J M
Laboratory of Materials and Interface Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, Netherlands.
Science. 2009 Mar 13;323(5920):1455-8. doi: 10.1126/science.1169434.
Biogenic calcium carbonate forms the inorganic component of seashells, otoliths, and many marine skeletons, and its formation is directed by an ordered template of macromolecules. Classical nucleation theory considers crystal formation to occur from a critical nucleus formed by the assembly of ions from solution. Using cryotransmission electron microscopy, we found that template-directed calcium carbonate formation starts with the formation of prenucleation clusters. Their aggregation leads to the nucleation of amorphous nanoparticles in solution. These nanoparticles assemble at the template and, after reaching a critical size, develop dynamic crystalline domains, one of which is selectively stabilized by the template. Our findings have implications for template-directed mineral formation in biological as well as in synthetic systems.
生物源碳酸钙构成了贝壳、耳石和许多海洋骨骼的无机成分，其形成由大分子的有序模板引导。经典成核理论认为晶体形成是由溶液中离子组装形成的临界核发生的。使用低温透射电子显微镜，我们发现模板导向的碳酸钙形成始于预成核簇的形成。它们的聚集导致溶液中无定形纳米颗粒的成核。这些纳米颗粒在模板处组装，达到临界尺寸后，形成动态晶域，其中一个晶域被模板选择性地稳定下来。我们的发现对生物系统和合成系统中模板导向的矿物形成具有启示意义。
