Porous protein-based scaffolds prepared through freezing as potential scaffolds for tissue engineering

Successful tissue engineering with the aid of a polymer scaffold offers the possibility to produce a larger construct and to mould the shape after the defect. We investigated the use of cryogelation to form protein-based scaffolds through different types of formation mechanisms; enzymatic crosslinking, chemical crosslinking, and non-covalent interactions. Casein was found to best suited for enzymatic crosslinking, gelatin for chemical crosslinking, and ovalbumin for non-covalent interactions. Fibroblasts and myoblasts were used to evaluate the cryogels for tissue engineering purposes. The stability of the cryogels over time in culture differed depending on formation mechanism. Casein cryogels showed best potential to be used in skeletal tissue engineering, whereas gelatin cryogels would be more suitable for compliable soft tissues even though it also seemed to support a myogenic phenotype. Ovalbumin cryogels would be better suited for elastic tissues with faster regeneration properties due to its faster degradation time. Overall, the cryogelation technique offers a fast, cheap and reproducible way of creating porous scaffolds from proteins without the use of toxic compounds.