Molybdenum Dioxide (MoS2)/Gadolinium (Gd) Containing Arginine-Glycine-Aspartic Acid (RGD) Sequences as New Nano-Contrast Agent for Cancer Magnetic Resonance Imaging (MRI)

Abstract

Molybdenum dioxide-gadolinium-arginine/glycine/aspartic acid (MoS2-Gd-RGD) sequences targeting nano-contrast agents that specifically bind to human hepatocellular carcinoma (HCC) HepG2 cells were synthesized, and their targeting imaging effects on HCC cells and models were evaluated. Zeta potential, particle size and Fourier Transform Infrared Spectrometer (FTIR) were used to characterize the nano-contrast agent, and its cytotoxicity was evaluated. The MoS2-Gd nanoparticles were used as control in vitro to determine the targeting capability of the MoS2-Gd-RGD nanoparticles toward integrin αvβ3. During in vivo animal experiments, 12 nude mice with tumors were randomly divided into three groups to compare the imaging effects of the MoS2-Gd-RGD and MoS2-Gd groups. The hydrodynamic diameter of MoS2-Gd-RGD nanoparticles was approximately 336.43±6.43 nm, and the polydispersity index (PDI) value reached 0.132. Transmission electron microscopy showed the uniform particle size and good dispersion of the nanoparticles. The relaxation rate totaled 1.39 mM−1S−1. The signal value of the T1-weighted image of the HepG2 cells treated with MoS2-Gd-RGD was higher than that of the non-targeted materials (MoS2-Gd) (P < 0.01). The signal value of the tumor increased significantly 15 min after the tail vein injection with MoS2-Gd-RGD, and it peaked at 60 min after injection. A significant difference in tumor signal values was observed between the two groups of nude mice injected with MoS2-Gd-RGD and MoS2- Gd (P < 0.01). At the in vitro and in vivo experiments, the MoS2-Gd-RGD nanoparticles presented the characteristics of integrin αvβ3 targeting. Thus, MoS2-Gd-RGD nanoparticles feature potential as contrast agents for MRI.