Departamento de Ingeniería Mecánica, Energética y de los Materiales, Universidad de Extremadura, Avda de Elvas s/n., 06006 Badajoz, Spain.
J Biomed Mater Res A. 2013 Dec;101(12):3551-9. doi: 10.1002/jbm.a.34657. Epub 2013 Apr 30.
In situ ring-opening polymerization of ε-caprolactone (ε-CL) was performed to coat β-tricalcium phosphate (β-TCP) scaffolds fabricated by robocasting in order to enhance their mechanical performance while preserving the predesigned macropore architecture. Concentrated colloidal inks prepared from β-TCP commercial powders were used to fabricate porous structures consisting of a three-dimensional mesh of interpenetrating rods. Then, ε-CL was in situ polymerized within the ceramic structure using a lipase as catalyst and toluene as solvent, to obtain a highly homogeneous coating and full impregnation of in-rod microporosity. The strength and toughness of scaffolds coated by ε-polycaprolactone (ε-PCL) were significantly increased (twofold and fivefold increase, respectively) over those of the bare structures. Enhancement of both properties is associated to the healing of preexisting microdefects in the bioceramic rods. These enhancements are compared to results from previous work on fully impregnated structures. The implications of the results for the optimization of the mechanical and biological performance of scaffolds for bone tissue engineering applications are discussed.
采用原位开环聚合的方法，将 ε-己内酯（ε-CL）涂覆在由 robocasting 制备的 β-磷酸三钙（β-TCP）支架上，以提高其机械性能，同时保持预定的大孔结构。使用商业 β-TCP 粉末制备的浓缩胶体油墨来制造由相互贯穿的棒状三维网格组成的多孔结构。然后，使用脂肪酶作为催化剂和甲苯作为溶剂，在陶瓷结构内原位聚合 ε-CL，以获得高度均匀的涂层和对棒内微孔的完全浸渍。与裸支架相比，涂覆 ε-聚己内酯（ε-PCL）的支架的强度和韧性显著提高（分别提高了两倍和五倍）。两种性能的增强都与生物陶瓷棒中先前存在的微缺陷的愈合有关。将这些结果与之前关于完全浸渍结构的研究结果进行了比较。讨论了这些结果对优化用于骨组织工程应用的支架的机械和生物学性能的意义。
