Controlled Precipitation of Biominerals using Catanionic Surfactant Self-Assembly Structures

使用阴离子表面活性剂自组装结构控制生物矿物沉淀

• 批准号: 5415807
• 负责人: Professor Dr. Helmut Cölfen (†)
• 金额: --
• 依托单位: Institut de Chimie Séparative de Marcoule (ICSM) - UMR 5257
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2004
• 资助国家: 德国
• 起止时间: 2003-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5415807?language=en
• 关键词: Controlled; Precipitation; Biominerals; using; Catanionic

Lyotropic phases could be used with great success as template for the synthesis of mesoporous ceramics via a sol-gel process. However, ion crystals could so far not be templated by such approach - likely as a result of the fluidity of the lyotropic phases. Salt-free catanionic surfactant systems offer a potential solution to this problem as their frozen bilayer structure displays great rigidity over large length scales. Furthermore, they show quite unique self-assembly structures. These phases shall be used as a template for the crystallization of CaCO3 within the water regime in the catanionic phase. For this, various crystallization techniques shall be employed which work at low ionic strength in order to reproduce the catanionic phase on the nm scale. The catanionic phases of particular interest are the lamella phases as well as the nanodisks and icosahedra. If CaCO3 could be mineralized within the lamellar phase, a layered organic-inorganic hybrid material similar to nacre with its superior mechanical properties would result. To achieve this, the catanionic aggregation has to be investigated in presence of the Ca2+ counterions and if necessary, the phase diagrams have to be determined. Also, it shall be explored, if very small pre-formed CaCO3 nanoparticles can be incorporated into the catanionic phases as material reservoir for later nanoparticle fusion via pH cycles. If it is possible to reproduce the organic template, other phase structures shall be employed in order to synthesize mesoscopically structured CaCO3 with various morphologies which will form a basis for the production of mesoscopically structured ionic crystals via the reproduction of soft superstructures in complex fluids. Such materials could find numerous potential uses for example as high strength materials, mesoporous storage or delivery systems, new optical or magnetic devices and so forth.

溶致相可以非常成功地用作通过溶胶-凝胶过程合成介孔陶瓷的模板。然而，离子晶体迄今为止还不能通过这种方法进行模板化——可能是由于溶致相的流动性的原因。无盐阴离子表面活性剂体系为该问题提供了潜在的解决方案，因为其冷冻双层结构在大长度尺度上表现出极大的刚性。此外，它们表现出相当独特的自组装结构。这些相应用作阴阳离子相中水体系中 CaCO3 结晶的模板。为此，应采用在低离子强度下工作的各种结晶技术，以便在纳米尺度上再现阴阳离子相。特别感兴趣的阴阴离子相是片层相以及纳米盘和二十面体。如果CaCO3可以在层状相内矿化，就会产生类似于珍珠质的层状有机-无机杂化材料，具有优异的机械性能。为了实现这一目标，必须在存在 Ca2+ 抗衡离子的情况下研究正离子聚集，如有必要，还必须确定相图。此外，还应探索是否可以将非常小的预成型 CaCO3 纳米颗粒纳入阴阳离子相中，作为后续纳米颗粒通过 pH 循环融合的材料库。如果可以复制有机模板，则应采用其他相结构来合成具有各种形貌的介观结构CaCO3，这将为通过在复杂流体中复制软超结构来生产介观结构离子晶体奠定基础。此类材料可以找到许多潜在用途，例如作为高强度材料、介孔存储或传输系统、新的光学或磁性装置等。