Reinforced gelatin-methacrylate hydrogels containing poly(lactic-co-glycolic acid) nanofiber fragments for 3D bioprinting

Abstract Hydrogel is an ideal material state for cell encapsulation. However, its biomechanical properties and cell growth are inversely proportional in 3D bioprinting applications. Here, we prepared a fiber-reinforced gelatin-methacrylate (gelMA) hydrogel bioink that can improve the compressive modulus and cell proliferation using poly(lactic-co-glycolic acid) n anofiber f ragments (PLGA-NF) as an artificial extracellular matrix to build patient specific soft tissues. The microstructures of the nanofiber fragments were observed via scanning electron microscopy. The degree of substitution of synthesized gelMA was investigated considering the mole ratio of MA and gelatin. The compressive modulus of hydrogels was measured using a texturometer. Cell viability of the encapsulated fibroblast was confirmed using live-dead stains. The morphology of actin, cytoskeleton, and nucleus of cells in gelMA/PLGA-NF bioinks were analyzed using phalloidin-DAPI stains. The viscosity and compressive modulus of the hydrogel were found to have significantly increased by the incorporation of 1 wt% PLGA-NF. Cell proliferation in bioprinted gelMA/PLGA-NF hydrogels was significantly increased in comparison to the control groups. The combination of hydrogel bioink with nanofibrous fragments will be a critical footstep in the field of 3D bioprinting.