Fig. 2
Biodistribution and clearance of 14C-graphene in male ICR mice after a intratracheally instillation or b oral gavage (5 μg 14C-graphene exposed) at different time points. c Raman spectra of the FLG obtained from stomach, small intestine, large intestine and lung after exposure for 1 d. Mouse feces were collected by metabolism cages. Data for the brain, heart, kidney, testis, muscle and blood for parts A and B and also the liver and spleen for part B were not shown because the radioactivity was always below the detection limit. The recovery of graphene in each organism tissue was in the range of 89 to 93 %. The data in the figure was corrected by these recovery values. The symbol‘*’indicates values that differed significantly from the control group at P ≤ 0.05. Data are presented as mean ± standard deviation (n = 5)