Arabinoxylan-based hydrocolloid bioink for 3D bioprinting: Improved printability, cell viability, and angiogenesis

This study investigates the potential of arabinoxylan-rich Psyllium Seed Hydrocolloid (PSH) as a bioink with enhanced pro-angiogenic potential for 3D bioprinting. PSH, derived from the Plantago ovata, is polysaccharide-based hydrocolloid with gel-forming ability. Here, aqueous extraction of PSH was done without post-processing to overcome the limitations caused by using toxic solvent. FTIR-ATR and SEM analyses were used to characterize extracted PSH bioink both chemically and morphologically. Arabinoxylan-rich PSH bioink showed a viscoelastic nature with shear-thinning ability, and high print-fidelity based on rheology and printability analyses, then optimal bioprinting parameters were determined to be 100 mg/mL, a 27G nozzle, and 10.5 psi. Further characterization was done by biodegradation and swelling tests, resulting in a 20.4-fold swelling ratio while gradual biodegradation was observed. Moreover, cell-laden structures were bioprinted using NIH-3T3 fibroblast cells, and homogeneous cell dispersion was visualized, with sustained cell viability and increased Collagen Type-I and F-actin expression observed over time. Besides, the pro-angiogenic potential of PSH was evaluated by an in ovo CAM assay, and increased vascular density was observed during embryonic development. Findings suggest that PSH is a promising bioink for bioprinting, supporting printability through enhanced viability, ECM production, and angiogenesis-associated behavior. Overall, this study integrates hydrocolloids with bioprinting, providing insights into eco-friendly, bioactive biomaterials for tissue engineering.