Evaluation of Three-Dimensional Porous Iron-Cross-Linked Alginate as a Scaffold for Cell Culture

We investigated the efficacy of three-dimensional porous ferric-ion-cross-linked alginate (Fe-alginate) gels as cell scaffolds, in comparison with calcium-ion-cross-linked alginate (Ca-alginate) gels. In a previous study, we had demonstrated that two-dimensional Fe-alginate film was an efficient material for use as a scaffold, allowing good cell adhesion and proliferation, unlike Ca-alginate film. In the present study, we fabricated three-dimensional porous Fe- and Ca-alginate gels by freeze-drying and evaluated their effects on cultured cells. The Fe-alginate gels showed higher protein adsorption ability than Ca-alginate gels. Cells formed multicellular spheroids in both types of alginate scaffold, but the number of cultured cells increased with culture time on Fe-alginate porous gels, whereas those on Ca-alginate gels did not. Moreover, it was revealed that the cells on Fe-alginate scaffolds were still viable inside the multicellular spheroids even after cultivation for 14 days. These results suggest that Fe-alginate provides a superior porous scaffold suitable for three-dimensional culture of cells. Our findings may be useful for extending the application of Fe-alginate to diverse biomedical fields.