Fig. 5

Tumor-targeting ability and therapeutic effect of SPION-Ex/MF in vivo. a Representative images showing the distribution of DiR-labeled SPION-Ex (5 mg/kg body weight) in BALB/c nude mice under an external magnetic field at 12, 24, 48, and 72 h after intravenous injection (n = 4 per group). The circles indicate the tumor sites. b Representative images showing the ex vivo fluorescence signals of DiR-labeled SPION-Ex (5 mg/kg body weight) in major organs (liver, spleen, lung, heart, and kidney) and tumors at 12, 24, 48, and 72 h after intravenous injection. c Representative images of subcutaneous xenograft tumors established using HGC27 cells in BALB/c nude mice. d Tumor growth was routinely examined, and the tumor growth curves in each group are shown. e Weights of harvested xenograft tumors. f Survival rates of mice receiving different treatments. g Body weights of mice at the end of the study. h–i Ki-67 staining of tumors from mice receiving different treatments, including PBS, SPION (2 mg/kg body weight), 5-FU (5 mg/kg body weight), N-Ex (5 mg/kg body weight), and SPION-Ex (5 mg/kg body weight), with or without MF. Scale bars, 100 μm. j–k TUNEL staining of tumors from mice receiving different treatments, including PBS, SPION, 5-FU, N-Ex, and SPION-Ex, with or without MF.