Engineering redox-active hyaluronan-ascorbate hydrogel microenvironments for β-cell protection during encapsulation and storage.

Cell-laden hydrogels used in β-cell encapsulation are exposed to oxidative and oxygen-transport stresses during fabrication, handling, and short-term storage. Here, we developed a redox-active hyaluronan-ascorbate conjugate (HA-Asc) as a biomaterial building block for β-cell-supportive hydrogels. HA was functionalised with ascorbate by EDC/NHS coupling and retained radical-scavenging activity while preserving a dominant high-molecular-weight polymer population. In INS-1E β-cells, soluble HA-Asc improved bioenergetic resilience after H2O2 challenge, increasing basal, maximal, and ATP-linked respiration relative to HA and oxidant-only controls. Physically assembled HA/HA-Asc cell-laden hydrogels also moderated intracellular oxidative activity after exogenous oxidant exposure. Under room-temperature transport-mimetic storage, HA/HA-Asc formulations reduced intracellular oxidative burden relative to HA alone, while oxygenated storage further limited lactate accumulation associated with hypoxia-driven glycolytic drift. Together, these findings show that covalent incorporation of ascorbate into HA creates a biofabrication-compatible redox microenvironment that combines HA processability with localized antioxidant function. This strategy provides a simple materials-chemistry route to improve the handling resilience of encapsulated β-cells in transport-relevant settings.