水热法合成含锌羟基磷灰石

Hydrothermal synthesis of zinc-substituted hydroxyapatite

自然骨中的无机组分并不是纯的羟基磷灰石[(Ca10(PO4)6(OH)2,Hydroxyapatite,简称HA],还含有微量镁离子(Mg2+)、锌离子(Zn2+)等。为满足临床的需要,常常需要在HA中添加锌元素制成含锌羟基磷灰石(Zn-HA),其有望成为新一代的骨修复和替换材料。以硝酸钙、磷酸三铵、硝酸锌为原料,在210℃下水热处理8h合成Zn-HA和Ca19Zn2(PO4)14混合粉末。采用X射线衍射(XRD)、电子扫描电镜(SEM)和热重—差热分析(TG-DTA)法对合成粉体的晶相、形貌和热稳定性进行分析。结果表明:在210℃、8h的实验条件下,反应釜的填充度较大时容易合成Zn-HA,但Zn掺量的摩尔分数不宜超过4%;随着Zn掺量和反应釜填充度的增加,HA的结晶度下降;Zn的掺入促使HA易分解,使其热稳定性较差。

The inorganic component of natural bone does not occur as pure hydroxyapatite（HA） due to the presence of minor constituents such as Mg2 ＋ and Zn2 ＋ etc.The attempt to meet the requirements for clinical applications results in the necessity of substituting some Zn elements into the HA to prepare the zincsubstituted hydroxyapatite（Zn-HA）,which is expected to become the new generation of bone repair and replacement materials.This paper introduces the preparation of the mixture powders of Zn-HA and Ca19Zn2（PO4）14 by the hydrothermal method at 210 ℃ for 8 h,using Ca（NO3）2,（NH4）3PO4 and Zn（NO3）2 as the raw materials.Characterizing the crystalline phase,morphology,and thermal stability of the prepared powders by X-ray diffraction（XRD）,scanning electron microscopy（SEM） and thermogravimetric-diferential thermal analysis（TG-DTA） shows that the easy synthesis of Zn-HA results,in the case of the larger compactness of reactor at this 210 ℃、8 h experimental conditions,but the mole fraction of zinc incorporated is not over more than 4%.The decreasing crystallinity of HA is governed by the increasing Zn incorporated and the compactness of reactor.Easy decomposition of HA due to Zn addition results in its poor thermal stability.