Gellan Gum/Polyvinyl Alcohol Hydrogels with Stress Relaxation Property for Application as Retinal Pigment Epithelial Cell Carrier

In this study, the stress relaxation of gellan gum (GG)/polyvinyl alcohol(PVA) hydrogel was evaluated according to the molecular weight of PVA. In addition, survival and proliferation of retinal pigment epithelium (RPE) were evaluated. After mixing GG with three molecular weights of PVA, Ca²⁺ was added to form a cross-link. The prepared viscoelastic hydrogels were designated as GG/PVA 146, GG/PVA 85, and GG/PVA 31 hydrogels. The physicochemical and mechanical properties of the GG/PVA hydrogel were evaluated, and in vitro experiments were conducted to confirm the effect of the GG/PVA hydrogel on the activity of ARPE-19 cells. As a result of the experiment, as the PVA molecular weight decreased, the hydrogel showed a high-water content, and we confirmed the fast stress relaxation property. In addition, rapid proliferation and spread were observed when ARPE-19 cells were cultured in gel. These results suggest that the applicability of the GG/PVA 31 hydrogel with fast stress relaxation as an ARPE-19 cell delivery system.