Submit Manuscript  

Article Details

Optimizing Contrast Effect in T1-Weighted Magnetic Resonance Imaging of Gd2O3-Based Nano-Agent via Dopamine Chelation

[ Vol. 4 , Issue. 4 ]


Haitao Huang, Lihui Weng and Jafar Golzarian*   Pages 249 - 254 ( 6 )


Background: The Ga-based nanoparticles are a promising contrast agent for T1-weighted MRI.

Objective: It is expected that small Gd2O3 nanoparticles will be modified with dopamine to give a relatively biocompatible surface, and even produce greater objects in nano-scale to inhibit in vivo clearance of the isolated Gd2O3 nanoparticles. Moreover, by tuning the plus sequence of MRI, the contrast effect of the resultant Gd2O3-based nano-agent modified with dopamine will be optimized.

Method: A kind of T1-weighted contrast nano-agent of MRI has been developed via a facile chelation of a catechol structure in dopamine with metal oxide nanoparticles.

Results: After the modification of dopamine, the Gd2O3 nanoparticles with an average size of ca. 3.7 nm formed some greater objects with a loose inner structure, and many Gd2O3 nanoparticles embedded into the formed greater objects. The longitudinal relaxivity (r1) of contrast agent based on dopaminemodified Gd2O3 nanoparticles could reach 2.11 mM-1s-1. The denser inner structure of dopaminemodified Gd2O3 nano-agent prepared for longer reaction time, together with the optimizing Gd concentration of1.00 mM and the longer repetition time, might contribute to better contrast effect.

Conclusion: Compared to the Gd2O3 nanoparticles, the dopamine-modified Gd2O3 nano-agent can be presented as the higher contrast signals in T1-weighted MRI by optimizing the pulse sequence, shown as the increasing brightness of field. The character of many small nanoparticles embedding into one greater objects might contribute a better local contrast effect and inhibit the in vivo clearance of isolated nanoparticles to meet the requirement of practical application.


Gd2O3 nanoparticles, dopamine, surface modification, T1-weighted MRI, chelation.


Department of Radiology, University of Minnesota, 420 Delaware Street SE, Minneapolis, MN 55455, Department of Radiology, University of Minnesota, 420 Delaware Street SE, Minneapolis, MN 55455

Graphical Abstract:

Read Full-Text article