模拟体液中生物大分子对类骨磷灰石矿化的影响

Effect of Biomolecules on the Formation of Bone-Like Apatite in Simulated Body Fluid

为考察体内生物大分子对羟基磷灰石(hydroxyapatite,HA)基底表面矿化物形成的影响,将牛血清白蛋白(bovine serum albumin,BSA)和硫酸软骨素(chondroitin sulfate,CS)大分子分别浸入模拟体液(SBF)中制备成2种矿化介质,再将HA浸入上述矿化介质中3 d观察类骨磷灰石形成过程。结果发现HA基底表面均沉积有Na+和CO32-取代的类骨磷灰石(Ca3.78Na0.02)(Ca5.22Na0.48)(CO3)1.5(OH)。BSA在2SBF中的存在促进了类骨磷灰石晶体在基材表面沉积,有利于其沿(300)晶面择优取向生长。CS对类骨磷灰石晶体的生长呈阻碍作用,获得的晶粒尺寸较小。模拟体液中BSA和CS大分子对类骨磷灰石晶体生长和形貌等均有一定的作用。

To explore the effect of biomolecules on the mineralization of hydroxyapatite surface, the macro-molecule of bovine serum albumin （BSA） and chondroitin sulfate （CS） were respectively plunged in simulation body fluid （SBF） to form the mineralizing mediums. Then the films of hydroxyappatite （HA） were immersed in SBF double concentrated （2SBF） modified with BSA and CS for 3 days and we observed the mineralization of bone-like apatite in SBF. The results showed that Na ^＋ and CO32- substituted bone-like apatite （ Ca3.78Na0.02 ） （ Ca Nao as ） （ PO4 ） 4.5 （ CO3 ） 1.5 （OH） were formed on the surface of HA film after soaked in modified 2SBF. The presence of BSA in 2SBF solution promoted the growth of bone-like apatite crystal,which tended to prefer orientation of crystals along （300） plane. However, CS strongly restrained the growth of HA crystal. When BSA and CS were mixed and co-existed in 2SBF solution,BSA advanced mineral crystal growth, while CS inhibited the growth.