Effects of macromolecule functionalization on the mechanical properties of PVA hydrogels

Synthetic vascular grafts can be used to repair damaged vessels for cardiovascular diseases. Polyvinyl alcohol (PVA) hydrogels are promising materials for the manufacturing of cellularized synthetic vascular grafts. Previous studies have demonstrated that functionalization of PVA with macromolecules such as gelatin, collagen among others, increases cell adhesion to the hydrogels. In this study we evaluated the effect on mechanical properties of these macromolecules on PVA blocks and thin tubes. A 9% PVA solution mixed with 1% of macromolecules (gelatin, collagen and fibroin) was used to manufacture blocks and tubes of PVA. The mechanical properties were assessed using a shear wave elastography approach and the group velocity to compare between the different conditions. The results of this study demonstrated that macromolecules can be used to modulate the mechanical properties since they tend to increase the materials Young’s modulus. On the contrary, the use of stabilizers and crosslinking agents such as glutaraldehyde (Glut), HC1 and acetic acid (AA) showed a decrease in the Young’s modulus and group velocity in the blocks and tubes.