Fig. 2

In vivo SPECT/CT imaging and antitumor evaluations using ¹³¹I-MnO₂-BSA on 4T1-bearing mice model. a Representative SPECT/CT planar imaging of 4T1 tumor-bearing mice post-i.t. injection of ¹³¹I-MnO₂-BSA at different time points, dose: 500 µCi; b Tumor growth curves of each mouse in different groups such as control, MnO₂-BSA, free ¹³¹I and ¹³¹I-MnO₂-BSA (dose: 500 µCi). c Time-dependent relative tumor volume variations of 4T1 tumor-bearing mice experiencing corresponding treatments in different groups including control, MnO₂-BSA, free ¹³¹I and ¹³¹I-MnO₂-BSA (dose: 500 µCi), where tumor volumes were normalized to initial values (V/V0). d Average tumor weight harvested from 4T1 tumor-bearing mice experienced different treatments in different groups at the end of experimental period (Day 12). e Body weight variation of 4T1 tumor-bearing Balb/c mice during treatment. f, g Optical microscopic images of H&E (f) and TUNEL-stained (g) tumor sections in different treatment groups (e.g., control, MnO₂-BSA, free ¹³¹I and ¹³¹I-MnO₂-BSA). P values were calculated by ANOVA (**P < 0.01 and ***P < 0.001). Data are expressed as mean ± SD (n = 5)