湿法合成纳米缺钙磷灰石的实验研究

Study on nano calcium-deficient hydroxyapatite synthesized by wet method

目的:合成与人体骨磷灰石成分接近的纳米缺钙磷灰石.方法:将(NH4)2HPO4和Ca(NO3)2按照2:1的比例混合、振荡合成、陈化24 h后,清洗、离心、烘干.采用X线衍射、透射电镜、红外光谱及能谱分析等实验手段,对合成的磷灰石进行观察与评价.结果:(NH4)2HPO4和Ca(NO3)2在震荡条件下进行化学湿法合成,可制备出长约40～60 nm,宽约15～22 nm左右的缺钙磷灰石颗粒.,这种颗粒结构与通常的针状羟基磷灰石结构相比,更接近于人体骨磷灰石(长约50～64 nm,宽度为24～30 nm);该颗粒具有与骨磷灰石接近的钙磷比、相似的纳米尺寸、较低的结晶度,还含有一定量的碳元素.其合成过程简便易行,原料来源普通、经济.因为与人体骨磷灰石有着诸多的相似之处,经过今后的生物学实验,将有望成为生物活性更高的体内植入材料.结论:利用湿法合成纳米缺钙磷灰石简便有效、成分稳定、晶粒形貌受环境温度影响小,在纳米尺寸和成分上与骨磷灰石高度相似.

AIM：To explore a better way to produce a kind of bioeeramic material which is likely to have super pefformance in vitro and in vivo biological tests. METHODS： （NH4 ）2HPO4 and Ca（ NO3 ）2 were used to produce nanosized calcium -deficient apatitic （CDHA） crystals with Ca/P ratios approximate to 1.5： 1. It＇s synthesized ly chemical wet method. The whole process includes mixing a suitable ratio of （NH4 ）2 HPO4/Ca（ NO3 ）2 into deionized water,shaking the aqueous solution under a pre - set temperature ,centrifugal washing aging for 24h and baking the precipitates. Energy dispersive of X -ray analysis was used to analyze the Ca/P ratio. The powders were examined under transmission electron microscope and analyzed with X -ray power diffraction. RESULTS ：Energy dispersive of X -ray analysis shows that the Ca/P ratios ap- proximate to 1.5：1 ,also the powder has certain percent of carbon element ,which exists in bone structure. XRD shows that the powder is lowly crystallized. TEM shows the powder is of rod - like shape with 15 - 22 mn in diameter and 50 - 60 nm in length. Since this powder has so ninny resembling characters with biological apatite crystals,a better biological performance is well expected. CONCLUSION：Nano calcium -deficient apatitic synthesized by chemical wet method is simple, convenient and constant. The crystal of this powder highly resembles the bone apatite crystals.