BACKGROUND:Colagen sponges are applied for hemostatic use, wound healing, and residual cavity filing, which have great values in clinical application and scientific research.
OBJECTIVE:To investigate the biological properties, biocompatibility and biodegradability of colagen spongesin vivo.
METHODS: The spatial structure, pore diameter and porosity of colagen sponges were characterized by scanning electron microscopy. Transmission electron microscopy was used to observe the conformation of colagen sponges. The secondary structure and thermal denaturation temperature of colagen sponges were
analyzed by circular dichroism spectrum. Colagen sponges were implanted intramuscularly into the spinal cord of New Zealand rabbits to observe the degradation and absorption and histological changesin vivo.
RESULTS AND CONCLUSION: Colagen sponges had porous structure with varying pore sizes ranging
40-150 μm, the mean pore size of 100 μm, the thickness wal of 1 μm, and a porosity of approximately 95.8%. Colagen sponges had a typical porous structure and periodic light and dark zones. The solution of colagen
sponges had a weak positive band near 220 nm and an intense negative band near 206 nm, which indicated a classic triple helix. And the secondary structure and thermal stability of colagen sponges were similar to that of
liquid colagen. Colagen sponges began to degrade at 4 weeks, and remained 20% at 12 weeks. These sponges had been associated with foreign body response and inflammation within 2 weeks after implantation. With wound healing, inflammatory reactions gradualy reduced and disappeared. During the implantation and degradation of sponges, no significant fibrous capsule formed and no tissue necrosis occurred at implantation site, indicating that colagen sponges have good performance in bioactivity, biocompatibility and degradation.