Study of folate receptor-targeted macromolecular gadolinium complex tumor contrast agent

Abstract

Targeted drug delivery can improve efficacy and reduce dose, so targeted drug delivery is a very ideal diagnostic imaging approach, and it is necessary to develop magnetic resonance imaging contrast agents with targeted effects. In this study, nuclear magnetic resonance contrast agent folic acid-chitosan/chitosan-diethylenetriaminepentaacetic acid-gadolinium nanoparticles (FA-CS/CS-DTPA-Gd NPs) was combined with folic acid (FA) group modified chitosan (CS) and diethylenetriaminepentaacetic acid-gadolinium complex (DTPA-Gd) modified chitosan. FA-CS/CS-DTPA-Gd NPs were characterized by fourier transform spectroscopy (FT-IR), nuclear magnetic resonance (1H NMR), dynamic light scattering (DLS) and transmission electron microscopy (TEM). The in vitro magnetic properties, cytotoxicity, and targeting to HeLa tumor cells of the nanoparticles were al so evaluated. The results showed that the prepared FA-CS/CS-DTPA-Gd NPs had uniform spheroid shape with particle size of 120.12 ± 1.29 nm; they had good magnetic properties with relaxation rate of 7.5 mM−1·s−1, which was 2.5 times that of DTPA-Gd; they had good in vitro cellular MR imaging and cell safety and could specifically target folic acid-overexpressing tumor cells. The results showed that nanoparticles could be used as targeted magnetic resonance imaging contrast agents in medical diagnostic imaging pathways.