Cai Zhu-Yun, Peng Fan, Zi Yun-Peng, Chen Feng, Qian Qi-Rong
Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.
Nanomaterials (Basel). 2015 Jul 31;5(3):1284-1296. doi: 10.3390/nano5031284.
Synthetic calcium phosphate (CaP)-based materials have attracted much attention in the biomedical field. In this study, we have investigated the effect of pH values on CaP nanostructures prepared using a microwave-assisted hydrothermal method. The hierarchical nanosheet-assembled hydroxyapatite (HAP) nanostructure was prepared under weak acidic conditions (pH 5), while the HAP nanorod was prepared under neutral (pH 7) and weak alkali (pH 9) condition. However, when the pH value increases to 11, a mixed product of HAP nanorod and tri-calcium phosphate nanoparticle was obtained. The results indicated that the pH value of the initial reaction solution played an important role in the phase and structure of the CaP. Furthermore, the protein adsorption and release performance of the as-prepared CaP nanostructures were investigated by using hemoglobin (Hb) as a model protein. The sample that was prepared at pH = 11 and consisted of mixed morphologies of nanorods and nanoprisms showed a higher Hb protein adsorption capacity than the sample prepared at pH 5, which could be explained by its smaller size and dispersed structure. The results revealed the relatively high protein adsorption capacity of the as-prepared CaP nanostructures, which show promise for applications in various biomedical fields such as drug delivery and protein adsorption.
合成磷酸钙（CaP）基材料在生物医学领域备受关注。在本研究中，我们研究了pH值对采用微波辅助水热法制备的CaP纳米结构的影响。在弱酸性条件（pH 5）下制备了分级纳米片组装的羟基磷灰石（HAP）纳米结构，而在中性（pH 7）和弱碱性（pH 9）条件下制备了HAP纳米棒。然而，当pH值增加到11时，得到了HAP纳米棒和磷酸三钙纳米颗粒的混合产物。结果表明，初始反应溶液的pH值对CaP的相和结构起着重要作用。此外，以血红蛋白（Hb）为模型蛋白，研究了所制备的CaP纳米结构的蛋白质吸附和释放性能。在pH = 11时制备的由纳米棒和纳米棱柱混合形态组成的样品比在pH 5时制备的样品表现出更高的Hb蛋白吸附能力，这可以用其较小的尺寸和分散的结构来解释。结果揭示了所制备的CaP纳米结构具有较高的蛋白质吸附能力，在药物递送和蛋白质吸附等各种生物医学领域具有应用前景。
