Functionalized Cellulose Hydrogel with Adhesive, Antioxidant and Ionically Conductive Properties

This study introduces a bio-inspired, dopamine-grafted carboxymethyl cellulose (CMCDA) hydrogel as a multifunctional platform for retinal tissue engineering and neuroprotection. Using 1D/2D NMR techniques, we provide a complete structural elucidation of this polysaccharide derivative, confirming amide formation alongside Schiff-base and Michael addition structures. In vitro assays demonstrate robust biocompatibility and potent reactive oxygen species (ROS) scavenging, effectively protecting retinal cells from oxidative stress. In vivo, using an optic nerve crush mouse model, intravitreal injection of a 7 wt% hydrogel emerged as the optimal formulation, significantly reducing ROS accumulation, preserving retinal ganglion cell (RGC) density, and markedly increasing axonal outgrowth.
The regenerative outcomes were further validated by RBPMS, beta III Tubulin, and GAP-43 immunostaining. Beyond its therapeutic efficacy, the CMCDA hydrogel exhibits superior thermal stability, tunable rheological properties, and high tissue adhesiveness. When integrated with a saturated NaCl solution, the hydrogel achieves stable ionic conductivity, enabling one week of continuous ECG monitoring with signal-to-noise ratios that surpass those of commercial conductive gels on curved skin surfaces. Ultimately, this work highlights the potential of sustainable, cellulose-based hydrogels as a unified strategy for minimally invasive retinal repair while serving as a high-performance interface for long-term biomedical sensing.