Figure 5From: Cellular distribution and cytotoxicity of graphene quantum dots with different functional groupsThe MTT (% of control) evaluated after exposed to three kinds of GQDs for 24 h. (a) MTT (% of control) of A549 cells after exposed to different concentrations of three kinds of GQDs. (b) MTT (% of control) of C6 after the exposure to three kinds of GQDs at different concentrations. Asterisk indicated p < 0.05 and double asterisk represented p < 0.01.Back to article page