Effect of mold shape on the microstructure of gelatin sponges for tissue engineering applications

Gelatin sponges have been used in several medical applications including tissue replacement, scaffolds, and hemostasis. Each application requires specific parameters that are tuned by the porosity of the sponges. Therefore, changes in the porosity profile of the sponges would change the sponge behavior. In this study, a gelatin solution was prepared and crosslinked with glutaraldehyde. Afterward, the solution was poured into three different mold structures with different volumes and frozen at a constant freezing rate. Each mold was investigated for its physical characteristics including swelling, degradation, porosity, crystallinity, and mechanical compression. Cube-molded gelatin sponges demonstrated high swelling capacity, degradation rate, and porosity while exhibiting low crystallinity, yield strength, and elasticity. These characteristics are suitable for hemostatic application and tissue regeneration. Therefore, it is recommended to freeze dry gelatin sponge in cuboid-shaped dimensions, for research or industry, to control the porosity and crystallinity of the sponge for the best result in biomedical applications.