A smart injectable composite hydrogel with magnetic navigation and controlled glutathione release for promoting chondrocyte array and self-healing in damaged cartilage tissue.

Injectable cell-based hydrogels allow surgical operation in a minimally invasive way for articular cartilage lesions but the chondrocytes in the injectable hydrogels are difficultly arrayed and fixed at the site of interest to repair the cartilage tissue. In this study, an injectable hyaluronic acid-polyacrylic acid (HA-pAA) hydrogel was first synthesized using hyaluronic acid-cyclodextrin (HA-CD) and polyacrylic acid-ferrocene (pAA-Fc) to provide cell-delivery and self-healing. To promote the cell fixation and alignment, porous poly(lactic--glycolic acid) (PLGA) magnetic microcapsules (PPMMs) with glutathione (GSH) loaded and iron oxide nanoparticles (IO) located in the shell were designed.