In vitro and in vivo biocompatibility of nano-hydroxyapatite/polyamide 66 as bone repair material / 中国组织工程研究

ABSTRACT

BACKGROUND: Nanohydroxyapatite reinforced polyamide 66 (n-HA/PA66) prepared using the novel process based on nanohydroxyapatite (n-HA) sol may promote the biocompatibility due to the well distribution of n-HA in the polyamide66 (PA66) matrix and chemical bond at organic-inorganic interface, n-HA/PA66 composite has been proposed as a premising bone repair biomaterial.OBJECTIVE: To investigate the biocompatibility of the novel material both in vitro and in vivo.METHODS: Primarily cultured osteoblasts were co-cultured with n-HA/PA66 and PA66. The cell attachment and morphology were studied using phase contrast light microscope (PCLM) and field-emission scanning electron microscope (FE-SEM).Moreover, n-HA/PA66 pins, with PA66 pins as control, were implanted into the right and left (control group) shinbone shafts of the rabbits, respectively. Materials were harvested at weeks 2, 8 and tissue sections were observed.RESULTS AND CONCLUSION- n-HA/PA66 and PA66 exhibited no cytotoxicity with osteoblasts, while the cellular morphology near the samples was better in the test group than in the control one. Moreover, the cell density attached on n-HA/PA66 was higher than that on PA66 and the cell number were especially different after co-culturing for 3 days (P < 0.01 ). The osteoblasts at the interface between the host bone and n-HA/PA66 also had a higher activity during the earlier period after implantation.Meanwhile the bone formation process was faster and effective in the experimental group. Results suggested that n-HA/PA66 prepared base on the n-HA sol has a better biocompatibility as compared with PA66.