FIG. 6.

Availability of cellular binding domain of FN on collagen–GAG and self-assembled type I collagen (CI) basal lamina analogs. A quantitative immunofluorescent assay was used to measure the availability of the cellular binding domain of FN on the surfaces of modified collagen membranes. At 100 μg/mL of FN, an increase in the cellular binding domain of FN was found when EDC conjugation was used in comparison to passive adsorption on collagen–GAG membranes (*p < 0.05, Student's t-test). At this concentration, an increase in the cellular binding domain of FN was also found on self-assembled CI membranes in comparison to collagen–GAG membranes, regardless of membrane modification strategy. When comparing modification strategies on self-assembled CI membranes, the binding domain of FN was statistically greater using EDC conjugation than when passive adsorption was used (*p < 0.05, Student's t-test). When evaluating the differences between concentrations of passively adsorbed and EDC-conjugated FN on self-assembled CI membranes, it was found that 100 μg/mL of FN was statistically greater than 30 μg/mL, but not 300 μg/mL for both modification strategies (**p < 0.05, one-way ANOVA with Tukey post hoc analysis). For collagen–GAG membranes, n = 8 for passive adsorption and n = 8 for EDC conjugation. For self-assembled CI membranes n = 4 for 30 and 300 μg/mL for both passive and EDC, and n = 8 for 100 μg/mL for both passive and EDC. Experiments were repeated and similar trends were found.