Figure 5. The degradation behavior and the morphology after degradation of A-SA-Gel and SA/Gel hydrogel samples: (A-A2) the surface morphology of A-SA-Gel hydrogel sample after degradation of 1, 3 and 5 days; (B-B2) the surface morphology of SA/Gel hydrogel sample after degradation of 1, 3 and 5 days; (C) weight loss ratio of A-SA-Gel and SA/Gel hydrogel samples in RPMI 1640 culture medium; (D) weight loss ratio of A-SA-Gel and SA/Gel hydrogel samples in PBS; (E) weight loss ratio of A-SA-Gel and SA/Gel hydrogel samples in PBS and culture medium after degradation of 5 days.