Mechanical properties of collagen-based scaffolds for tissue regeneration

[摘要] (cont.) The mechanical properties were lower for the more highly mineralized scaffolds as a result of an increase in the number of defects such as cracked and disconnected walls. Next, we attempted to increase the mechanical properties by increasing the relative density of the MCG scaffolds. The volume fraction of solids in the slurry was increased by a vacuum-filtration technique. The slurry was then freeze-dried in the conventional manner to produce scaffolds with increased relative densities. Increasing the relative density by a factor of 3 increased the dry Young;;s modulus and crushing strength roughly by 9 and 7 times, respectively, allowing the dry scaffolds to withstand hard thumb pressure. The Young;;s modulus for the densest scaffold in the hydrated state was in the optimum range for MSC to differentiate into bone cells. Further, we attempted to improve the mechanical properties of the CG scaffold using the same technique. We were able to achieve an increase in its tensile Young;;s modulus in the dry state by a factor of aboutl0 times. Finally, the fraction of MC3T3 cells attaching to the CG scaffolds was found to increase linearly with the specific surface area of the scaffold, or with the number of binding sites available for cell attachment.

[发布机构] Massachusetts Institute of Technology