Taguchi T, Kishida A, Akashi M
Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering, Kagoshima University, Japan.
J Biomater Sci Polym Ed. 1999;10(8):795-804. doi: 10.1163/156856299x00883.
The aim of this study is to clarify the physico-chemical factors which influence apatite formation on/in a hydrogel during a novel alternate soaking process. A poly(vinyl alcohol) (PVA) gel was used as a model matrix. The amount of apatite formed on/in PVA gels decreased with an increase in the reaction temperature during the same reaction cycles. This suggested that the equilibrium swelling ratios decreased with increasing reaction temperatures; that is, the diffusion of calcium and phosphate ions reduced at high reaction temperature. However, the crystallinity of apatite formed on/in PVA gels was greater at higher reaction temperatures. The amount of apatite formed on/in PVA gels increased with an increase in the calcium and phosphate solution concentrations, and increased by shaking at the first three reaction cycles. A few influences could be observed when the solution volume was changed, however, the soaking order was not effective in this study. These results indicate that the amount of apatite formation on/in PVA gels can be controlled by changing the reaction temperature and the Ca- and P-solution concentrations, and that the crystallinity of apatite can be also changed by controlling the reaction temperatures.
本研究的目的是阐明在一种新型交替浸泡过程中影响水凝胶上/水凝胶内磷灰石形成的物理化学因素。使用聚乙烯醇（PVA）凝胶作为模型基质。在相同的反应周期内，PVA凝胶上/凝胶内形成的磷灰石量随反应温度的升高而减少。这表明平衡溶胀率随反应温度的升高而降低；也就是说，在高反应温度下钙和磷酸根离子的扩散减少。然而，在较高反应温度下，PVA凝胶上/凝胶内形成的磷灰石结晶度更高。PVA凝胶上/凝胶内形成的磷灰石量随钙和磷酸盐溶液浓度的增加而增加，并在前三个反应周期通过振荡而增加。当溶液体积改变时，可以观察到一些影响，然而，浸泡顺序在本研究中没有效果。这些结果表明，通过改变反应温度以及钙和磷溶液的浓度，可以控制PVA凝胶上/凝胶内磷灰石的形成量，并且通过控制反应温度也可以改变磷灰石的结晶度。
