Fig. 5.

Biodistribution and therapy effect of Mn-ZnO₂ NPs on p53-mutant tumor. Biodistribution of (a) Zn and (b) Mn (% ID of Zn or Mn per gram of tissues) in major organs and tumor after intravenous administration of Mn-ZnO₂ NPs for different time intervals (0, 4, 12, and 24 h) (n = 3). *p < 0.05, **p < 0.01. (c) In vivo T₁-weighted MRI images of MDA-MB-231 tumor-bearing mice after intravenous injection of Mn-ZnO₂ NPs for different time intervals (0, 4, 12, and 24 h). Yellow circle indicated the tumor region. (d) Average intensity of MRI signals at the tumor site. *p < 0.05, **p < 0.01. (e) Schematic illustration of the experimental setup for in vivo p53-mutated tumor therapy using Mn-ZnO₂ NPs. (f) Photos of the tumorous region in the mice with different treatments (saline, Zn²⁺ + Mn²⁺, ZnO₂ NPs, or Mn-ZnO₂ NPs). (g) Time-dependent tumor progression (volume-based) in mice with different treatments. (h) Terminal weights of tumors resected from mice with different treatments. *p < 0.05, **p < 0.01. (i) Photos of the terminal tumors harvested from mice with different treatments (day 16).