Fig. 1From: Graphene oxide-modified silk fibroin/nanohydroxyapatite scaffold loaded with urine-derived stem cells for immunomodulation and bone regenerationa Macroscopic images of the scaffolds containing various concentrations of GO before or after cross-linking. b SEM images of the scaffolds. Scale bar = 200 μm. c Average pore size of each scaffold. d Porosity of each scaffoldBack to article page