γ-Fe2O3@
DMSA-DG NPs was prepared. The degree of A549 cells targeted absorption of γ-Fe2O3@
DMSA-DG NPs was detected by
Prussian blue staining, colorimetric assay, T2W and multi-echo sequence MRI. γ-Fe2O3@
DMSA NPs was used as a control agent, and free
D-glucose as a competitive inhibitor. Human
lung adenocarcinoma A549 xenograft
tumor was prepared in nude mice. Sterile aqueous
suspension of γ-Fe2O3@
DMSA NPs or γ-Fe2O3@
DMSA-DG NPs was injected into the tail vein of nude mice. Before and 6, 12, 24, 48 h after injection, MRI imaging of the mice was performed. T2 signal intensity of the
tumor, brain, liver and thigh skeletal muscles, and T2 values of the
tumors were measured.
RESULTS: The average diameter of the particles was about 10 nm, and there were no significant differences between the diameters of γ-Fe2O3@
DMSA NPs and γ- Fe2O3@
DMSA-DG NPs. The IR spectra showed the C-N retractable vibration peak at γ-Fe2O3@
DMSA-DG NPs surface, indicating that 2-DG was conjugated to the γ-Fe2O3@
DMSA NPs. The
Prussian blue staining, colorimetric assay, MRI T2 signal intensity and T2 values revealed that γ-Fe2O3@
DMSA-DG NPs were significantly more absorbed by A549 cells at growth peak than γ-Fe2O3@
DMSA NPs, and the absorption of γ-Fe2O3@
DMSA-DG NP was inhibited by free
D-glucose. The results of in vivo examination showed that before and at 6, 12, 24, 48 h after injection of γ-Fe2O3@
DMSA-DG NPs, the mean T2 signal intensities of the
tumors were (326.00 ± 16.26)s, (276.40 ± 5.13)s, (268.40 ± 30.58)s, (240.40 ± 25.93)s, (262.20 ± 30.04)s, respectively, and the T2 values of the
tumors were (735.80 ± 20.93) ms, (645.80 ± 69.58) ms, (615.00 ± 124.61) ms, (570.60 ± 67.78) ms, and (537.80 ± 105.29) ms, respectively. However, before and at 6, 12, 24, 48 h after injection of γ-Fe2O3@
DMSA NPs, the mean T2 signal intensities of the
tumors were (335.60 ± 4.93)s, (290.80 ± 5.93)s, (273.40 ± 15.08)s, (327.40 ± 16.65)s, and (313.20 ± 20.45)s, respectively, and T2 values were (686.00 ± 21.44)ms, (617.80 ± 69.93)ms, (645.20 ± 85.89)ms, (669.40 ± 13.72)ms, and (608.80 ± 61.90)ms, respectively. The T2 signal intensity and T2 value of the
tumors were not declined generally after injection. The liver T2 signal intensity was decreased after injection of both γ-Fe2O3@
DMSA-DG NPs and γ-Fe2O3@
DMSA NPs, and T2 signal intensity of the brain and muscle did not show significant changes.
CONCLUSIONS: