A dual-mode T1 MRI/CT contrast agent of Gd2O3/Au@MSNs for tumor imaging with high performance

• Published in: Materialia Vol. 24; p. 101494
• Main Authors: Yang, Jianfeng, Zhao, Qingling, Zang, Zehao, Zhang, Shuquan, Wang, Ziwu, Li, Lanlan, Yu, Xiaofei, Yang, Xiaojing, Lu, Zunming, Zhang, Xinghua
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2022
• Subjects: Computed tomography imaging; Gadolinium oxide; Magnetic resonance imaging; Relaxivity; Tumor imaging; Magnetic resonance imaging; Relaxivity; Computed tomography imaging; Tumor imaging; Gadolinium oxide
• ISSN: 2589-1529; 2589-1529
• DOI: 10.1016/j.mtla.2022.101494

Magnetic resonance imaging (MRI) contrast agents with high relaxivity is of great importance for clinical diagnosis. Here we propose an effective method to enhance the relaxivity of MRI contrast agents. Ultra-small gadolinium oxide nanoparticles (Gd2O3 NPs) with different surface ligands were prepared by coprecipitation method, and the polyacrylic acid (PAA) modulated Gd2O3 NPs (PAA-Gd2O3) have the high r1 relaxivity of 53.34 mM–1 s–1, which is mainly induced by the strong affinity between PAA and water molecules. In addition, PAA modulated Gd2O3 NPs were successfully loaded on Au@MSNs (Au nanorod coated with mesoporous silica, Gd2O3/Au@MSNs) with enhanced affinity between Gd3+ and water molecules, as well as increased motional time of Gd3+. Therefore, the r1 relaxivity of Gd2O3/Au@MSNs can be up to 64.53 mM–1 s–1, which is 17 times of the commercial agent Gd-DTPA. The Gd2O3/Au@MSNs NPs also have a low r2/r1 of 1.04 and good computed tomography (CT) imaging performance, as well as good biocomatibility, which have great potential applications in multimodal bioimaging. [Display omitted]