交联温度对京尼平交联胶原/壳聚糖组织工程支架的影响

Effect of temperature on crosslinking of collagen/chitosan scaffolds with genipin

[目的]通过研究材料的孔径、交联度、溶胀率、降解率、细胞毒性及组织相容性的变化,探讨交联温度对京尼平交联胶原/壳聚糖支架的影响。[方法]采用冷冻干燥法制备胶原/壳聚糖复合多孔支架,分别于4℃、20℃、36℃条件下,在0.5%京尼平水溶液中交联24h。以未交联的胶原/壳聚糖复合多孔支架作为对照,评价所得支架的孔径、交联度、溶胀率、降解率、细胞毒性及组织相容性特点。[结果]随交联温度升高,支架的交联度明显增大,溶胀率和降解率逐渐减小。4℃组支架交联度47.88%±6.4%,溶胀率为721%±46%,4周后降解3.95%±6.4%;20℃组支架交联度67.69%±3.6%,溶胀率为662%±72%,4周降解0.91%±5.9%;36℃组支架交联度70.32%±5.7%,溶胀率为635%±27%,4周降解0.66%±7.3%,三组上述观察指标均优于未交联组(P/0.01)。[结论]京尼平交联可以显著降低胶原/壳聚糖支架的降解率和溶胀率,且对支架结构和生物相容性无明显影响。交联温度增加可以提高支架的交联度和抗降解能力,较快获得具有良好生物相容性和降解率的组织工程支架。

[ Objective] To investigate the changes of pore sizes, crosslinking index, swelling ration, degradation rate, cytotoxicity and biocompatibility of genipin crosslinked collagen/chitosan scaffolds affected by the different crosslinking temperature points. [ Method] The freeze- dried collgaen/chitosan scaffolds crosslinked with 0. 5% genipin within 24 h were divided into 3 groups by crosslinking temperature： 4℃ group, 20℃ group and 36℃ group. The characteristics of pore sizes, crosslinking index, swelling ratio, degradation rate, cytotoxicity and biocompatibility were evaluated. Collagen/chitosan scaffolds without crosslinking were chosen as control group. [Result] With the increase of temperature, crosslinking index was increased, but swelling ratio and degradation rate were decreased. In 4℃ group, the crosslinking index was 47. 88% ± 6. 4%, the swelling ratio was 721% ±46%, and the degradation rate was decreased by 3.95%±6.4% at 4 weeks. In 20℃ group, the crosslinking index was 67. 69% ±3.6%, the swelling ration was 662%± 72%, and the degradation rate was 0. 91% ±5.9% in 4 weeks. In 36℃ group, the crosslinking index was 70. 32% ±5.7%, the swelling ration was 635% ±27%, and the degradation rate was 0. 66% ±7. 3% at 4 weeks. The above indexes of the three groups were much better than those of control group （P 〈 0. 01 ） . [ Conclusion] It was indicated that the swelling ratio and degradation rate of the collagen/chitosan scaffolds are significantly decreased by genipin without any obvious change of pore sizes and toxicity. The biocompatibility and degradation rate of this tissur engineering scaffold can be well obtained with genipin by increasing crosslinking temperature within 24 h.