Department of Industrial Engineering, University of Salerno, 84084 Fisciano, SA, Italy.
SuMo BIOMATERIALS, VINN Excellence Center, Chalmers University of Technology, Göteborg, Sweden; Pharmaceutical Technology, Chemistry and Chemical Engineering, Chalmers University of Technology, Göteborg, Sweden.
Mater Sci Eng C Mater Biol Appl. 2016 Jan 1;58:442-9. doi: 10.1016/j.msec.2015.08.040. Epub 2015 Sep 1.
Alginate solutions in the presence of bivalent ions can form ionic cross-linked gels. In particular gelation conditions the gel structure can be characterized by great anisotropy with the presence of straight capillaries along a preferential direction. These materials can find applications mainly in high-tech sectors, like tissue engineering, where the gel characteristics play a crucial role. Despite the need of mastering the capillary formation and properties, the process remains a poorly known problem, and its development is left to trial and error procedures. In this work a quantitative approach to the description of the capillary formation process has been developed. The theory proposed by Treml et al. (2003) has been implemented and extended to an alginate different from the one used in that study and two different ions (calcium and copper). Some of the model parameters have been derived through simple measurements; others have been scaled using proper scaling equations. Experiments have been performed in different gelation conditions, varying alginate and ionic solution concentrations, to highlight the effects of these parameters on the anisotropic structure and to validate the model. In all the analyses done, the model has performed nicely showing a good reliability in the prediction of gel characteristics like capillary formation, capillary length and process time.
海藻酸盐溶液在二价离子存在的情况下可以形成离子交联凝胶。在特定的凝胶形成条件下，凝胶结构具有很大的各向异性，存在沿优先方向延伸的直毛细通道。这些材料主要可以应用于高科技领域，如组织工程，其中凝胶特性起着至关重要的作用。尽管需要掌握毛细通道的形成和特性，但该过程仍然是一个知之甚少的问题，其发展仍然依赖于反复试验的方法。在这项工作中，我们提出了一种定量描述毛细通道形成过程的方法。我们实现并扩展了 Treml 等人（2003 年）提出的理论，用于研究与该研究中所用的海藻酸盐不同的海藻酸盐，以及两种不同的离子（钙和铜）。模型中的一些参数是通过简单的测量得到的；其他参数则使用适当的缩放方程进行了缩放。我们在不同的凝胶形成条件下进行了实验，改变了海藻酸盐和离子溶液的浓度，以突出这些参数对各向异性结构的影响，并验证模型。在所有进行的分析中，该模型表现良好，在预测凝胶特性（如毛细通道形成、毛细通道长度和过程时间）方面表现出很好的可靠性。
