Advanced Biomaterials and Tissue Engineering Center, Huazhong University of Science and Technology, Wuhan, 430074, China.
Advanced Biomaterials and Tissue Engineering Center, Huazhong University of Science and Technology, Wuhan, 430074, China; Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China.
Colloids Surf B Biointerfaces. 2019 Jul 1;179:121-127. doi: 10.1016/j.colsurfb.2019.03.063. Epub 2019 Mar 28.
Interconnected porous scaffolds are widely used in the applications of tissue repair and regeneration. Sustained local delivery of drugs and growth factors around the implanted scaffolds could accelerate the growth of cells and contribute to the regeneration of damaged tissues. In this study, porous hydroxyapatite composite scaffolds were prepared through 3D bio-printing for bone tissue engineering and were subsequently coated with chitosan and sodium hyaluronate by layer-by-layer (LBL) deposition. It was found that the LBL coating on the porous scaffolds could reduce the swelling ratio of scaffolds in size and increase the compressive strength by about 70%. The degradation rate of the scaffolds slowed down due to the LBL coating. Rhodamine B (RHB) and bovine serum albumin (BSA) were chosen as model drugs in order to understand the loading and release behaviors of the scaffolds. Small RHB molecules could penetrate deep into the LBL coated scaffolds and released a little slower than that without coating. Meanwhile, large BSA molecules showed faster release rate compared to that without coating. In addition, there was no significant cytotoxicity effect of these composite scaffolds towards MC-3T3E1 cells and the scaffolds provided proper conditions for cell adhesion and proliferation, indicating that the printed hydroxyapatite composite scaffolds exhibit a great potential in hard tissue engineering as a sustained delivery system.
多孔互联支架广泛应用于组织修复和再生领域。在植入支架周围持续局部输送药物和生长因子可以加速细胞的生长，促进受损组织的再生。在这项研究中，通过 3D 生物打印制备了用于骨组织工程的多孔羟基磷灰石复合支架，随后通过层层（LBL）沉积对其进行壳聚糖和透明质酸钠的涂层处理。研究发现，多孔支架的 LBL 涂层可以将支架的溶胀率降低约 70%，同时增加其压缩强度。由于 LBL 涂层的存在，支架的降解速度也会减慢。本研究选择了罗丹明 B（RHB）和牛血清白蛋白（BSA）作为模型药物，以了解支架的载药和释放行为。小分子 RHB 可以深入渗透到 LBL 涂层的支架中，释放速度比没有涂层的支架稍微慢一些。同时，大分子 BSA 的释放速度比没有涂层的支架更快。此外，这些复合支架对 MC-3T3E1 细胞没有明显的细胞毒性作用，并且为细胞黏附和增殖提供了适当的条件，这表明打印的羟基磷灰石复合支架作为一种持续释放系统，在硬组织工程中有很大的应用潜力。
