Fogde Anna, Rosqvist Emil, Le Trung-Anh, Smått Jan-Henrik, Sandberg Thomas, Huynh Tan-Phat
Laboratory of Molecular Science and Engineering, Åbo Akademi University, 20500, Turku, Finland.
Department of Mechanical and Materials Engineering, University of Turku, 20014, Turku, Finland.
Chempluschem. 2023 Feb;88(2):e202200426. doi: 10.1002/cplu.202200426.
Originating from the concept of classical chemical gardens, a new field coined 'chemobrionics' has recently emerged. In the present work, two chemobrionic systems grown from a hydrogel/liquid interface at different time scales (for 1, 7, 14 or 28 days) were investigated, i. e., a calcium-based hydrogel with a phosphate counterion solution (Ca-gel) and a phosphate-based hydrogel with a calcium counterion solution (P-gel). The initial pH changes of the systems were investigated, and the obtained tubular structures were studied using optical microscopy, SEM, AFM, PXRD and TGA. One of the important findings is that the tubes obtained in the Ca-gel system were straight and long, which could be explained by the larger pH difference observed between the hydrogel and the counterion solution in this system (ΔpH∼2.1) compared to the P-gel system (ΔpH∼0). The Ca-gel structures remained overall more amorphous even though increased crystallinity was observed in both systems with increased time spent in counterion solution. Both systems contained hydroxyapatite phases, with additional calcite phases observed for the P-gel structures and traces of κ-carrageenan for the Ca-gel structures. Our study provides a promising method for controlling tubular macrostructures through adjusting the reaction conditions such as maturation time and pH.
源于经典化学花园的概念，一个新的领域——“化学仿生学”最近出现了。在本工作中，研究了在不同时间尺度（1、7、14或28天）从水凝胶/液体界面生长的两种化学仿生系统，即具有磷酸盐抗衡离子溶液的钙基水凝胶（Ca-凝胶）和具有钙抗衡离子溶液的磷酸盐基水凝胶（P-凝胶）。研究了系统的初始pH变化，并使用光学显微镜、扫描电子显微镜、原子力显微镜、粉末X射线衍射和热重分析对所得管状结构进行了研究。一个重要的发现是，在Ca-凝胶系统中获得的管子又直又长，这可以用该系统中水凝胶和抗衡离子溶液之间观察到的较大pH差异（ΔpH2.1）来解释，相比之下P-凝胶系统的pH差异为ΔpH0。即使在两个系统中随着在抗衡离子溶液中停留时间的增加都观察到结晶度增加，但Ca-凝胶结构总体上仍保持更多的非晶态。两个系统都含有羟基磷灰石相，P-凝胶结构中观察到额外的方解石相，Ca-凝胶结构中观察到痕量的κ-卡拉胶。我们的研究提供了一种通过调节反应条件（如成熟时间和pH）来控制管状宏观结构的有前景的方法。
