Fig. 6

Evaluating the cytotoxic effects of Co₃O₄ NPs synthesized using Viobrio sp VLC, and cisplatin on different cell lines. a, c Viability rate of CT26 and NIH/3T3 cells after exposing to different concentration of Co₃O₄ NPs, respectively. b, d Viability rate of CT26 and NIH/3T3 cells after exposing to different concentration of cisplatin, respectively. e Comparison between IC₅₀ values of Co₃O₄ NPs on CT26 and NIH/3T3 cells at 24, 48, and 72 h. The results are indicated as mean ± SD (****p < 0.0001). The results demonstrated that the rate of inhibition and the percentage of cell viability decreased with increasing concentration and duration. Both Co₃O₄ NPs and cisplatin had strong inhibitory effects on CT26 cells, but Co₃O₄ NPs had a much smaller inhibitory effect on NIH/3T3 cells and were much less cytotoxic.