Porous calcium phosphate coating over phosphorylated chitosan film by a biomimetic method
Porous calcium phosphate coating over phosphorylated chitosan film by a biomimetic method
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DOI：
10.1016/s0142-9612(98)00243-9
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发表时间：
1999-05-01
期刊：
影响因子：
14
通讯作者：
Kameyama, T
中科院分区：
文献类型：
--
作者：
Varma, HK;Yokogawa, Y;Kameyama, T
采用扫描电镜、X射线能谱、显微傅里叶变换红外光谱（micro-FTIR）和薄膜X射线衍射（XRD）等分析手段，研究了在壳聚糖膜上沉积多孔磷酸钙涂层的过程。壳聚糖膜首先通过将壳聚糖粉末溶解在稀乙酸中并在帽形培养皿中干燥来制备。使用尿素和H3 PO 4对膜进行磷酸化，其中P含量为0.1- 0.2wt%。磷酸化膜在饱和Ca（OH）（2）溶液中浸泡8天导致在整个表面上形成磷酸钙前体相。当浸入1.5 x SBF中超过20天时，这种前体相刺激了缺钙羟基磷灰石多孔涂层的生长。未用Ca（OH）（2）处理的磷酸化膜在浸入SBF溶液中时没有显示出任何磷酸钙生长。前体相被认为是磷酸八钙，其在SBF处理期间成核HAP相。最初，在SBF中的这种处理导致在膜表面上形成单层磷酸钙颗粒。随着在SBF中浸泡时间的增加，进一步的成核和生长产生多孔HAP涂层。HAP涂层的Ca/P比是SBF浸泡时间的函数。(C)1999爱思唯尔科技有限公司。保留所有权利。
A porous calcium phosphate coating deposited on chitosan films was studied using scanning electron microscopy, energy-dispersive X-ray analysis, micro-Fourier transform infrared spectroscopy (micro-FTIR) and thin-film X-ray diffractometry (XRD). Chitosan films were first prepared by dissolving chitosan powder in dilute acetic acid and drying in a hat petri dish. The films were phosphorylated using urea and H3PO4 with the P content being 0.1-0.2 wt%. Phosphorylated films soaked in saturated Ca(OH)(2) solution for 8 days led to the formation of a calcium phosphate precursor phase over the entire surface. This precursor phase stimulated the growth of a porous coating of calcium-deficient hydroxy apatite when immersed in 1.5 x SBF for mon than 20 days. Phosphorylated films not treated with Ca(OH)(2) did not show any calcium phosphate growth upon immersion in SBF solution. The precursor phase is thought to be octacalcium phosphate, which nucleates a HAP phase during SBF treatment. Initially, this treatment in SBF results in the formation of a single-layer calcium phosphate particles over the film surface. As immersion time in SBF increases, further nucleation and growth produce a porous HAP coating. The Ca/P ratio of the HAP coating is a function of SBF immersion time. (C) 1999 Elsevier Science Ltd. All rights reserved.