In this study, we propose a gellan gum (GG)/polyvinyl alcohol (PVA) viscoelastic hydrogel for retinal pigment epithelium (RPE) cell delivery and regeneration. The GG/PVA viscoelastic hydrogel was prepared by divalent cation Ca2+ ion bonding using calc...
In this study, we propose a gellan gum (GG)/polyvinyl alcohol (PVA) viscoelastic hydrogel for retinal pigment epithelium (RPE) cell delivery and regeneration. The GG/PVA viscoelastic hydrogel was prepared by divalent cation Ca2+ ion bonding using calcium chloride (CaCl2) as an ionic crosslinking agent. The prepared viscoelastic hydrogels were classified into three types according to the difference in molecular weight and we were evaluated through characterization and in vitro studies to compare whether they were suitable for retinal tissue engineering. The prepared GG/PVA viscoelastic hydrogels were classified into GG/PVA 31, GG/PVA 85, and GG/PVA 146. Stress relaxation characteristics of GG/PVA viscoelastic hydrogels according to the difference in PVA molecular weight. In addition, ARPE-19 accordingly Proliferation, spread, and growth of cells were confirmed. First, the prepared GG/PVA viscoelastic hydrogel was confirmed by FT-IR analysis to confirm the chemical properties of the structural change of the molecule. Physical and mechanical properties suitable for cells were confirmed by evaluating sol fraction, mass swelling ratio, weight loss, and mechanical properties. The pore size and porous structure of the GG/PVA viscoelastic hydrogel were observed with a scanning electron microscope (SEM). Viability and cytotoxicity of ARPE-19 cells in GG/PVA viscoelastic hydrogel were confirmed by MTT assay and live & dead staining. In addition, proliferation and differentiation of ARPE-19 cells in the hydrogel were confirmed through dsDNA quantitative analysis. As a result of the experiment, as the molecular weight of PVA decreased, it showed a low compressive modulus close to the retinal modulus, high swelling property, and the fastest stress relaxation. In addition, it was observed that ARPE-19 cells encapsulated in GG/PVA 31 rapidly proliferated and spread. Through these results, the GG/PVA 31 viscoelastic hydrogel was confirmed to be applicable as a cell carrier for RPE cell delivery and regeneration.