A comparison of 2 kinds of hydroxyapatite/collagen composites as tissue engineering scaffold / 第二军医大学学报

ABSTRACT

Objective: To prepare 2 composites using different proportions of hydroxyapatite and collagen and to assess their structural and biological properties, so as to pave a way for preparing tissue engineering chest wall scaffold. Methods: Two kinds of hydroxyapatite/collagen composites were prepared according to the weight ratios of 11 and 12; collagen sponge served as control. Then the structures of the 2 composites and the collagen sponge were observed under SEM. In vivo study was conducted to assess the biocompatibility and biodegradation of the composites by gross inspection and histological examination. Results: The collagen sponge had a 3-D network structure with fluey collagen fibers and poor mechanical strength, and its structure was damaged within 2 weeks after implantation and was completely absorbed 4 weeks later. The hydroxyapatite and collagen were well mixed in the composite with a hydroxyapatite to collagen ratio of 12; the composite had homogeneous 3-D porous structure (size of the pore being 100-400 m) and showed good biocompatibility maintained its porous structure 4 weeks after implantation and was absorbed within 8 weeks. In composite with hydroxyapatite to collagen ratio of 11, the hydroxyapatite particles were separated from collagen fiber and conglomerated into masses, and the composite resulted in severe tissue reaction after implantation. Conclusion: When mixed with a reasonable proportion of hydroxyapatite, the collagen sponge has improved structure, biodegradable performance, and biocompatibility; the composite may be a novel scaffold for tissue engineering chest wall reconstruction.