Biodegradable and functionalizable 3D-printed stimuli-responsive hydrogels

In this study, we developed innovative biodegradable and functionalizable 3D-printed stimuli-responsive hydrogels for advanced biomedical applications such as drug delivery and tissue engineering. Utilizing polyethylene glycol (PEG) polymers, the hydrogels incorporated redox-sensitive disulfide linkages for stimuli-responsive behavior. The custom synthesized PEG-disulfide crosslinker (PEGSSDMa) provided stability and redox responsiveness. PEGMEMa enhanced porosity and swelling ratios, while PEGDMa added network stability. The fabrication used extruder-based 3D printing for precision, with gellan gum increasing the viscosity of the hydrogel precursor solution to maintain structural fidelity. UV crosslinking post-printing enhanced mechanical integrity and resistance to dissolution. These hydrogels demonstrated a balanced combination of robustness and biodegradability, tailored to degrade at controlled rates. The redox-responsive nature enabled targeted release of therapeutic agents in specific physiological environments, enhancing treatment efficacy and safety. Functionalizing hydrogels with bioactive molecules promoted cell adhesion, proliferation, and differentiation, essential for tissue regeneration. This study advances biomedical engineering by developing multifunctional hydrogels that integrate biodegradability, functionalizability, and stimuli-responsiveness, paving the way for new therapeutic strategies.