Figure 1.

GO sheets translocate to the lower respiratory tract after intranasal instillation. Mice were instilled with DOTA‐functionalized GO sheets labeled with ¹¹⁵In (natural) or ¹¹¹In (radioactive), and the organs were collected 1 and 7 days after exposure. A) Autoradiography of lungs dissected from mice instilled with GO‐DOTA[¹¹¹In] 1 day after exposure. B) Heatmap illustrates tissue distribution and persistence of GO‐DOTA[¹¹⁵In] in the respiratory tract compared to DOTA[¹¹⁵In] control, at days 1 and 7 after i.n. instillation. Each block represents the mean amount of GO in the respective organ, quantified by ICP‐MS, which was normalized as % instilled dose (ID) per gram of dry tissue. C) Quantification of ¹¹⁵In by ICP‐MS in the lungs and trachea from mice exposed to GO‐DOTA[¹¹⁵In] or the DOTA[¹¹⁵In] control reveals size‐dependent distribution of GO in the respiratory tract. Individual data points corresponding to each animal are plotted alongside mean ± SD (n = 4). Data were analyzed using a two‐way ANOVA test with post hoc Sidak's multiple comparisons test. Significant differences between treatments are plotted with (*), whereas differences over time are plotted with (#). In both cases, statistical significance is reported as: (*), p < 0.05; (**), p < 0.01; (***), p < 0.001; (****), p < 0.0001. Remaining organs are plotted in Figure S2, Supporting Information.