Figure 6: Influence of concentration of ferric ions cross-linked with alginate on the growth of NHDF. Cells were seeded on Fe-alginate gels with a low concentration of ferric ions, being cross-linked with 50 mM FeCl3 at a density of 4000 cells/cm2, and numbers of attached cells were counted at 1, 5, and 8 days after the start of culture (a). Thickness (b) and dry weight (c) were also measured to evaluate the properties of the Fe-alginate gel. Error bars indicate standard deviation for . *.