Fig. 17

Electrically stimulated 3D-bioprinted GelMA-PPy-Fe hybrid hydrogel induces osteogenesis and bone regeneration by regulating collective signaling pathways and immunopolarization. a Schematic illustration of the ink deposition process. b FE-SEM images of the freeze-dried GelMA, GelMA-PPy, and GelMA-PPy-Fe hydrogel scaffolds. c Conductivity of the GelMA-PPy and GelMA-PPy-Fe hydrogels. d Determination of the mechanical integrity of 3D printed complex architectures using GelMA-PPy bioink. e Schematic illustration of the cell culture procedure showing the protocol for cell-laden culture (3D), and the cell viability of 3D bioprinted hBMSCs after 5 days of incubation was also determined. f Macrophage polarization potential of Raw 264.7 cells cultured with the fabricated scaffolds. g Schematic illustration of the osteo- immunomodulation experiment and the ARS staining of hBMSCs in the presence of M-CM after 7 and 14 days of induction. Images reproduced from [60], © 2023 Elsevier Ltd