Dopamine-modified chitosan hydrogel for spinal cord injury.

Spinal cord injury (SCI) decreases people's both physical and psychological levels. The rehabilitation of SCI is still a clinical challenging process owing to the inflammatory environment for cell survival. Herein, we designed a dopamine-modified chitosan hydrogel to improve poor microenvironment of spinal cord injury. Dopamine modified chitosan hydrogel was fabricated by crosslinking with citric acid (CS-CA-DA), which address the insufficient mechanical properties. In vitro analysis showed that dopamine modification improved the cell survival and cell adhesion. Moreover, implantation of CS-CA-DA hydrogel alone into rat injured spinal cord helped improving cell survivals, modulating immunity, promoting macrophage polarization to the M2 phenotype and promoting axonal regeneration in vivo in brutal areas of SCI. This strategy of modified chitosan with dopamine undergoing a high mechanical properties, excellent cell compatibility and antioxidant performance, providing a new insight into repairing spinal cord injury.