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.