Figure 3.

(A) Schematic illustration of the Ca²⁺-SCNF gel formation by Ca²⁺ mediated nanofibers aggregation via neutralizing sulfate groups’ negative charge. (B) Digital photographs of SCNF solution and Ca²⁺-SCNF hydrogel. (C) Frequency sweep ramp performances of the SCNF solution and Ca²⁺-SCNF hydrogel. (D) The G′ and G′’ values of Ca²⁺-SCNF hydrogels at 1 Hz. Values are presented as mean ± SD, n = 3. (E) Shear-rate-dependent viscosity moduli of the Ca²⁺-SCNF hydrogels. (F) Images of Vero E6 cells after 2 h incubation without and with Ca²⁺-SCNF hydrogel, in which FITC signal (in green) stands for hydrogel and Hoechst signal (in blue) stands for cell nuclei. Scale bar: 20 μm.