掺锌对β-磷酸三钙陶瓷的微观结构和烧结特性的影响

用化学共沉淀法制备了β-磷酸三钙(tricalcium phosphate,TCP)和不同掺锌量的β-磷酸三钙前躯体,不同含锌量的磷酸三钙前驱体粉末在850℃煅烧2h,制备出β-TCP和不同掺锌量的β-TCP粉末。X射线衍射结果显示,随掺锌量的增加β-TCP晶体的晶格参数常数a(b)和c减小,并可显著提高其晶相转变温度,掺锌量为2.5%(摩尔分数,Zn与Zn+Ca的摩尔比)的β-TCP转变为α-TCP的温度可从1150℃提高到1300℃。扫描电镜照片、抗弯强度和显气孔率结果表明,锌的掺杂有助于制备力学性能良好的致密β-TCP陶瓷。用掺锌2.5%的β-TCP坯体在1100℃烧结2h得到了力学性能良好的致密β-TCP陶瓷。     

Preparation and Characterization of β-TCP/CS Scaffolds by Freeze-extraction and Freeze-gelation

The freeze-extraction and freeze-gelation methods were used to prepare highly porous β-TCP/CS scaffolds with different β-TCP/CS ratio.In these methods,the suspending mixture of β-TCP and chitosan was frozen,the frozen mixture was immersed in a non-solvent(0.05mol/L NaOH/ehanol aqueous) bath to allow the exchange between solvent(acetic-acid aqueous) and non-solvent at a temperature lower than the freezing point of the acetic-acid.Then,the β-TCP/CS scaffolds were formed and dried at room temperature.Scanning ...     

β-磷酸三钙/壳聚糖复合支架的制备及其对成骨细胞生长的影响

采用冷冻萃取和冷冻凝胶法制备了β-磷酸三钙/壳聚糖(-βTCP/CS)复合支架,并采用SEM、XRD、FTIR和万能材料试验机对其性能进行表征。研究结果表明,复合支架的孔隙率85%,且随-βTCP含量的增加而减小。力学性能的测试结果显示,当壳聚糖含量为30%时,复合支架的抗压强度最大(1.73MPa)。同时SEM结果表明壳聚糖与-βTCP的比值为30∶70时,复合支架的孔径在200～500μm之间。将成骨细胞MC-3T3-E1接种于-βTCP/CS复合支架上,培养7d后,发现细胞在-βTCP/CS复合支架上能够很好地粘附、生长和分化,即所制备的复合支架具有良好的细胞相容性。