Development of a Photo-crosslinkable Sodium Alginate-GelMA Bioink for 3D Bioprinting of Functional Tissue Constructs

Abstract

The rapid growth of 3D bioprinting has opened new avenues for fabricating functional tissue constructs. However, a major bottleneck is the lack of an ideal bioink that simultaneously offers good printability, mechanical strength, and biocompatibility. To address these limitations, we developed a photo-crosslinkable hybrid bioink composed of sodium alginate and gelatin methacrylate (GelMA). GelMA was synthesized in-house, and its photo-crosslinking behavior was optimized using Irgacure 2959 as a photoinitiator. Sodium alginate was added to improve the viscosity and printability of the formulation for precise and tunable extrusion-based 3D bioprinting. The developed bioink exhibited good resolution with excellent printability (Pr value = 0.99 ± 0.04) and strong shape fidelity. Mechanical testing revealed a compressive modulus of 83.36 ± 9.17 kPa. Biological assays demonstrated excellent cytocompatibility and hemocompatibility. Live/dead and DAPI/F-actin staining confirmed high post-printing cell viability, uniform distribution, and excellent cell attachment within the constructs. Our optimized hybrid bioink may offer a promising solution for high-resolution 3D bioprinting with excellent printability and biocompatibility for creating functional tissue constructs.