RESUMO
BACKGROUND:In previous studies, the dehydrothermal cross-linking method was modified by the authors to improve the degradation property of colagen scaffolds. The cross-linking time was increased from 24 to 48 hours, and the cross-linking temperature increased from 105 to 115℃. OBJECTIVE:To verify the anti-degradation ability of colagen scaffolds prepared using the modified dehydrothermal cross-linking method and to obtain the optimal efficacy of the scaffolds on damaged tissue repair and regeneration. METHODS: Highly-purified type I colagen scaffolds with native triple helix structure were prepared and subjected to three different dehydrothermal cross-linking conditions: 105℃ for 24 hours, 105℃ for 48 hours and 115℃ for 24 hours. Material samples, 1 cm×1 cm, were implanted subcutaneously into the rat dorsum. The specimens were harvested at 3 days, 14 days and 42 postoperative days folowed by fixation and histological analysis using hematoxylin-eosin staining. RESULTS AND CONCLUSION:No untoward foreign body and immunological reactions were observed in any groups. In the group of 105℃ for 48 hours, the scaffold retention and degree of pore openness were better than the other two groups at 14 days after scaffold implantation (P < 0.05). These findings indirectly suggest that the anti-degradation ability of colagen scaffolds can be strengthened under certain dehydrothermal cross-linking conditions: the cross-linking time is increased from 24 to 48 hours.