Biomaterial Research Center, Division of Life Sciences, Korea Institute of Science and Technology, 39-1 Hawolgok-dong, Seongbook-Ku, Seoul 136-791, South Korea.
J Biomater Sci Polym Ed. 2010;21(3):289-302. doi: 10.1163/156856209X415792.
Tissue-engineered vascular grafts have been investigated as a substitute for prosthetic vascular grafts. The current scaffolds have several limitations due to weak mechanical properties in withstanding the pressure of blood vessel. A gel-spinning molding device including three-separate drivers that make a cylindrical shaft turn on its axis, orbit, and concurrently move up and down was developed for preparing seamless fibrous tubular scaffolds for vascular grafts. A seamless double-layered tubular scaffold, which was composed of an outer fibrous network and inner porous layer, was fabricated by using the device for the spinning of poly(L-lactide-co-caprolactone) (PLCL, 50:50) solution as a gel state on a rotating cylindrical shaft that had been dip-coated with the mixture of PLCL solution and NaCl particles. A scaffold that had an inner layer fabricated with 30% salts, below 20 mum in salt size, and more than 100 microm in thickness, was found to be optimal from a blood leakage test. The burst pressures of the scaffolds were more than 900 mmHg. The scaffolds exhibited 550-670% elongation-at-break. The measured circumferential and longitudinal tensile strengths of the scaffolds were 3.62 +/- 0.68 and 2.64 +/- 0.41 MPa, respectively. The suture retention strength of the scaffold was measured to be 7.68 +/- 0.75 N. These mechanically strong and elastic properties of the newly developed scaffolds provide an important basis for blood vessel tissue engineering.
组织工程血管移植物已被研究作为人工血管移植物的替代品。由于当前支架的机械性能较弱，无法承受血管的压力，因此存在一些局限性。为了制备用于血管移植物的无缝纤维管状支架，开发了一种包括三个独立驱动器的凝胶纺丝成型装置，该驱动器可使圆柱形轴绕其轴旋转、轨道旋转并同时上下移动。使用该装置，将聚（L-丙交酯-共-己内酯）（PLCL，50:50）溶液纺成凝胶状态，在已浸涂有 PLCL 溶液和 NaCl 颗粒混合物的旋转圆柱形轴上，制备出无缝双层管状支架。从渗漏试验来看，由内层制造的支架，其盐含量为 30%，盐粒径小于 20 微米，厚度大于 100 微米，是最佳的。支架的爆裂压力超过 900mmHg。支架的断裂伸长率为 550-670%。支架的环向和纵向拉伸强度分别为 3.62 +/- 0.68 MPa 和 2.64 +/- 0.41 MPa。支架的缝合保持强度测量值为 7.68 +/- 0.75 N。这些新开发的支架具有较强的机械性能和弹性，为血管组织工程提供了重要基础。
