Dupraz A M, de Wijn J R, v d Meer S A, de Groot K
Biomaterials Research Group, University of Leiden, Netherlands.
J Biomed Mater Res. 1996 Feb;30(2):231-8. doi: 10.1002/(SICI)1097-4636(199602)30:2<231::AID-JBM13>3.0.CO;2-P.
Hydroxyapatite (HA) powder was treated with different silane adhesion promoters, to optimize its performance as a filler in polymer composites. The silane coupling agents investigated possessed vinyl, methacryloxy, primary amine, secondary amine, and diamine functionality. The different coatings were evaluated with respect to their influence on ionic exchange. X-ray photoelectron spectroscopy revealed the presence of a few monolayers thin silane films on HA powder. Silane coupling agents were able to bond chemically on the HA surface because a thin coating remained after washing of the powder with water. The water stability of this bond was evaluated by successive extractions and was judged limited, especially in the case of the hydrophilic aminosilanes. Zeta-potential measurements indicated the "transparency" of the coatings for ionic transport, that was corroborated by two in vitro dissolution studies, in Gomori's Tris-maleate buffer, and in simulated body fluid. However, aminosilane coatings could delay the release of calcium and phosphate ions during the first 2 days of immersion of treated HA powder in Gomori's buffer.
用不同的硅烷粘合促进剂处理羟基磷灰石（HA）粉末，以优化其作为聚合物复合材料填料的性能。所研究的硅烷偶联剂具有乙烯基、甲基丙烯酰氧基、伯胺、仲胺和二胺官能团。评估了不同涂层对离子交换的影响。X射线光电子能谱显示HA粉末上存在几层薄的硅烷膜。硅烷偶联剂能够在HA表面发生化学键合，因为用水洗涤粉末后仍保留有一层薄涂层。通过连续萃取评估了这种键合的水稳定性，结果表明其稳定性有限，尤其是对于亲水性氨基硅烷而言。ζ电位测量表明涂层对离子传输具有“透明性”，这在两项体外溶解研究中得到了证实，一项是在戈莫里氏马来酸三羟甲基氨基甲烷缓冲液中，另一项是在模拟体液中。然而，在处理过的HA粉末浸入戈莫里氏缓冲液的头两天内，氨基硅烷涂层可以延迟钙和磷酸根离子的释放。
