Fig. 5. Graphitic nanodiamonds produced increased levels of cellular oxidative stress for (a) MDA-MB-231 cells. Graphitic diamonds had a significant d-statistic (= 4.6 > d-critical = 2.3) and TBHP performed successfully as the positive control (significant d-statistic = 8.7 > d-critical = 2.3) (b) MCF-7 cells (significant d-statistic = 5.7 > d-critical = 2.3). TBHP, the positive control performed as expected 3.6 > d-critical = 2.3. Oxidized diamonds did not increase the cellular stress in either cell line. Oxidative stress was generally higher at 1 h time point for graphitic diamonds. Outliers greater than 1.5× the interquartile range were not plotted. d-Statistics were used in place of p values, as the sample did not reflect a normal distribution, and so the analysis was done on ranked data. Nimages = 24, 31, 33, 15, 25, 24, 33, 31 (column order), Ncells = 451, 478, 671, 368, 530, 433, 897, 773.
