Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, India.
J Biomater Sci Polym Ed. 2011;22(16):2107-26. doi: 10.1163/092050610X534230. Epub 2010 Nov 9.
The present work focuses on the physical, mechanical and in vitro properties of porous inorganic/organic biocomposite scaffolds of polyvinyl alcohol-tetraethylorthosilicate-alginate-calcium oxide (PTAC). These scaffolds are prepared by means of cryogelation technology and are intended for bone tissue engineering applications. The biocomposite cryogels have much more favorable physical and biological properties compared to the previous work of our group on the same composition in the form of pellets and foams. The optimized and heat-treated PTAC biocomposite cryogels show homogenous porosity and good mechanical properties and also exhibit the formation of a hydroxyapatite-like layer on their surface on coming in contact with simulated body fluid (SBF). Furthermore, the biocomposite cryogels showed good biocompatibility with L929 fibroblasts. Also, the influence of pre-soaking in SBF to that of non-soaked scaffolds was compared in terms of proliferation of MG-63 osteoblast-like osteosarcoma cells on these scaffolds and it was found that the pre-soaking caused a decrease in cell proliferation. Finally, the response of human osteoblasts on these scaffolds was analyzed by MTT assay, scanning electron microscopy, energy dispersive X-ray spectroscopy and micro X-ray computing tomography. The cells revealed good biocompatibility with the biocomposite cryogels and were mostly present as cell sheets on the surface with thick bundles of collagenous extracellular matrix during initial period of incubation. During later phases, the formation of calcium phosphate-like mineral deposits was observed on the surface of the cryogels suggesting a high potential of the biocomposite cryogels towards bone regeneration. Therefore, the PTAC biocomposite cryogels, due to their favorable properties and high biocompatibility with human osteoblasts can be suggested as potential scaffolds for bone tissue engineering applications.
本工作重点研究了聚乙烯醇-正硅酸乙酯-海藻酸钠-氧化钙（PTAC）多孔无机/有机生物复合材料支架的物理、机械和体外性能。这些支架是通过冷冻凝胶技术制备的，用于骨组织工程应用。与我们之前在相同组成的微球和泡沫形式的研究相比，生物复合冷冻凝胶具有更理想的物理和生物学性能。优化和热处理后的 PTAC 生物复合冷冻凝胶具有均匀的多孔性和良好的机械性能，并且在与模拟体液（SBF）接触时表面形成类似羟基磷灰石的层。此外，生物复合冷冻凝胶与 L929 成纤维细胞具有良好的生物相容性。还比较了在 SBF 中预浸泡对非浸泡支架的影响，即在这些支架上 MG-63 成骨样骨肉瘤细胞的增殖方面，发现预浸泡导致细胞增殖减少。最后，通过 MTT 测定、扫描电子显微镜、能谱分析和微 X 射线计算机断层扫描分析了这些支架上的人成骨细胞的反应。细胞与生物复合冷冻凝胶具有良好的生物相容性，在孵育初期，细胞主要以细胞层的形式存在于表面，并有厚束胶原细胞外基质。在后期，观察到冷冻凝胶表面形成类似磷酸钙的矿物质沉积，表明生物复合冷冻凝胶具有很高的骨再生潜力。因此，由于其良好的性能和与人成骨细胞的高生物相容性，PTAC 生物复合冷冻凝胶可作为骨组织工程应用的潜在支架。
