Fig. 1
From: Potential use of 3D-printed graphene oxide scaffold for construction of the cartilage layer
a Scanning electron microscopy (SEM) image showing the flake-like morphology of the graphene oxide (GO). b Size distribution of the GO flakes measured by an electric potential-based spectrophotometer. The size distribution showed the majority of GO was smaller than 100 μm. c FTIR adsorption spectra of chemical ingredients involved in the GO and bone morphogenetic protein 2 (BPM2)-GO: A peak value of 1800/cm confirms that carboxyl (C=O) played a key role in the BPM2-GO. d Coexistence of chondrocytes with GO: The quantity of cells around the GO increased in 10 day in the cell co-culture group