Fig. 4
a T1-MR images of SKOV-3 tumor-bearing mice before and after direct injection of Pt@mPDA/MnO2/PDA NPs (50 μL in PBS; [Mn] = 50 mM) into tumor (right, circle indicated) and muscle (left, circle indicated) tissues; b The quantified T1-MR signals corresponding to (a); c T1-weighted images of mice bearing SKOV-3 tumor grafts (arrow indicated) intravenously injection with Pt@mPDA/MnO2/PDA NPs or Pt@mPDA/MnO2/PDA-ZHer2 NPs ([Mn] = 3 mM, 100 μL in PBS per mouse) at 1 h, 3 h and 6 h, respectively; d The quantified T1-MR signals corresponding to (c)