Figure 4.

a) Imaging of the living mouse bearing subcutaneously implanted HepG2 tumors after 12 h i.v. injection of Pd‐MX (0.6 mL, 20 × 10⁻⁶ m). Note: because the tumors were implanted in the back near the right lower hand of mice, so the tumor was performed to image in a prone position and the liver was performed to image in a supine position. b) Phosphorescence intensity histograms of the tumor regions and liver regions in the living mouse bearing subcutaneous tumor. c) Phosphorescence lifetime histograms of the tumor regions and liver regions in the living mouse bearing subcutaneous tumor. d) The oxygen pressure histograms of the tumor regions and liver regions in the living mouse bearing subcutaneous tumor.