Aryaei Ashkan, Liu Jason, Jayatissa Ahalapitiya H, Jayasuriya A Champa
Department of Mechanical Engineering, University of Toledo, Toledo, OH 43606, USA.
School of Medicine, University of Toledo, OH 43614, USA.
Mater Sci Eng C Mater Biol Appl. 2015 Sep;54:14-9. doi: 10.1016/j.msec.2015.04.024. Epub 2015 Apr 22.
Calcium phosphate (CaP) cements are highly applicable and valuable materials for filling bone defects by minimally invasive procedures. The chitosan (CS) biopolymer is also considered as one of the promising biomaterial candidates in bone tissue engineering. In the present study, some key features of CaP-CS were significantly improved by developing a novel CaP-CS composite. For this purpose, CS was the first cross-linked with tripolyphosphate (TPP) and then mixed with CaP matrix. A group of CaP-CS samples without cross-linking was also prepared. Samples were fabricated and tested based on the known standards. Additionally, the effect of different powder (P) to liquid (L) ratios was also investigated. Both cross-linked and uncross-linked CaP-CS samples showed excellent washout resistance. The most significant effects were observed on Young's modulus and compressive strength in wet condition as well as surface hardness. In dry conditions, the Young's modulus of cross-linked samples was slightly improved. Based on the presented results, cross-linking does not have a significant effect on porosity. As expected, by increasing the P/L ratio of a sample, ductility and injectability were decreased. However, in the most cases, mechanical properties were enhanced. The results have shown that cross-linking can improve the mechanical properties of CaP-CS and hence it can be used for bone tissue engineering applications.
磷酸钙（CaP）骨水泥是通过微创手术填充骨缺损的高适用性和高价值材料。壳聚糖（CS）生物聚合物也被认为是骨组织工程中很有前景的生物材料候选者之一。在本研究中，通过开发一种新型的CaP-CS复合材料，显著改善了CaP-CS的一些关键特性。为此，首先将CS与三聚磷酸钠（TPP）交联，然后与CaP基质混合。还制备了一组未交联的CaP-CS样品。根据已知标准制备并测试样品。此外，还研究了不同粉液比的影响。交联和未交联的CaP-CS样品均表现出优异的抗冲洗性。在湿态下对杨氏模量、抗压强度以及表面硬度观察到最显著的影响。在干燥条件下，交联样品的杨氏模量略有提高。根据给出的结果，交联对孔隙率没有显著影响。正如预期的那样，通过增加样品的粉液比，延展性和可注射性降低。然而，在大多数情况下，力学性能得到了增强。结果表明，交联可以改善CaP-CS的力学性能，因此可用于骨组织工程应用。
