Fig. 4
A The linear fitting of 1/T1 of BFE@BSA NPs at different Fe3+ concentrations. The T1-weighted MR images (B) and T1 mapping images (C) of BFE@BSA NPs nanoparticle in vitro. D The T1 WI and T1 Map of BFE@BSA NPs nanoparticle for cellular imaging. E The T1 value of each group (n = 3). F Schematic description of in vivo MR scanning plan. G The axial T1 WI of mice at different time points. The quantitative analysis of relative T1 signal (H) and SNR (I) in tumor region (n = 6, the same mouse for continuous monitoring). J The coronal T1 WI and T1 Map of mice at different time points. The quantitative analysis of SNR (K) and T1 value (L) in tumor region (n = 3, different mice for each time point). F The in vivo biodistribution of the DiR-loaded BFE@BSA NPs (n = 3). G The quantitative analysis of fluorescence intensity in tumor