In Vitro Degradation of Silk Fibroin/Hyaluronic Acid Composite Hydrogels

Protein-polysaccharide scaffolds are usually used in tissue engineering; however, matching regeneration rate with healing modes is a challenge because of unpredictable scaffold degradation profiles. We investigated the effect of the blend ratio on degradation behavior of silk fibroin (SF)/hyaluronic acid (HA) hydrogels by varying weight ratios. The hydrogels were incubated in 1 U/mL collagenase IA at 37 °C to create an in vitro model of proteolytic degradation. Samples were harvested at designated time points up to 21 days and scanning electron microscopy (SEM), digital photos, and mass loss were investigated. Control samples were incubated in phosphate-buffered saline. The results showed regular and controllable degradability. The higher the HA content, the stronger the degradability of the hydrogel. When the HA content increased from 20% to 40%, the mass loss of the hydrogel increased from 22% to 35% after 21 days of degradation.