Effect of Heat Level and Expose Time on Denaturation of Collagen Tissues

Introduction: The applied heat level and expose time are main issues in certain operations/applications, such as a laser assisted tissue welding, preparation of collagen-based biomaterials (films, implants). Therefore, the precise investigation of these parameters is crucial. The results can serve as a guideline to assess potential effects while maintaining the functionality of the collagen structures. Methods: Collagen tissues from rat-tail tendon, calfskin, and bones are soaked in buffer solutions, then examined by microscope at different temperature levels. Results: Increase in temperature reduced the microscopically observed collagen crimp contrast for calfskin and rat-tail tendons but not for bone tissues. The contrast level for rat tail tendon decreased down to 80% of its initial value at 37, 157, and 266 s for 70, 65, and 60 °C, respectively. The decrease in the crimp contrast was about only 25% and 2% at 55 and 50 °C after 2 h, respectively. 50% drop in contrast level was occurred for the skin samples at 16, 90, 110 and 1900 s for 70, 65, and 60 °C, respectively. The bone samples, did not show any significant differences in contrast levels. Conclusion: The observed denaturation behaviours are in line with Arrhenius Law. This study could be expanded on to other types of tissues at wider temperature ranges to make a guideline for biological/medical processes that radiate heat in order to assess their side effects on collagen and other proteins.