3.9. Serum supplemented scaffolds greatly increased cytotoxicity
DPSCs cultured for 24h in serum-free media on all graphene-based scaffolds caused no significant increases in cytotoxicity levels compared to cell only (2D) control, irrespective of coating conditions (Fig. 8a). The data also indicated significantly lower cell toxicity of PLL+LAM-coated RGOSA1 scaffolds (1.81%±3.57), compared to no scaffold condition. Furthermore, quantitative LDH activity measurements (Fig. 8b) showed no significant differences after 24 hours between all 3D graphene-based scaffolds seeded with DPSCs using serum-containing media, when compared to 2D control. These cytotoxic effects were not influenced by coating conditions. However, the percentage of cytotoxic effects of PLL+LAM-coated SA scaffolds (24.83%±4.77) was the highest amongst other scaffolds assessed across all coating conditions.
There are no significant increases in the percentage of cell toxicity of DPSCs exposed to coated and uncoated GOSA and RGOSA scaffolds in comparison to the 2D control (Fig. 8c). However, after 48 h of cell culture, a significant elevation of LDH release was detected when DPSCs were cultured on SA scaffolds with serum deprivation, with the highest cell toxicity percentage of 36.22%±1.26 for PLL+LAM coating. The cell toxicity percentage of almost all samples tested with no serum was found to have increased in comparison to the corresponding conditions at the 24 h time point. In addition, when DPSCs in serum-rich media were seeded onto fabricated 3D scaffolds, cell toxicity of scaffolds increased significantly in comparison with no scaffold culture, regardless of coating conditions (Fig. 8d). After 48h of DPSCs culture with serum, cell cytotoxicity was the highest in SA (20.78%±2.95), GOSA1 (16.95%±3.38), and RGOSA1 (16.43%±3.58) matrices coated with PLL. Furthermore, at 48 h of cell culture with serum, the cell toxicity percentage of all evaluated samples was reduced when compared with the corresponding 24 h time point.