Large-Scale Synthesis of Ultrathin Manganese Oxide Nanoplates and Their Applications to T1 MRI Contrast Agents

• DOI: 10.1021/cm200414c
• Publication Date: 2011-06-30T20:28:33Z
• Authors: Mihyun Park; Nohyun Lee; Seung Hong Choi; Kwangjin An; Seung-Ho Yu; Jeong Hyun Kim; Seung-Hae Kwon; Dokyoon Kim; Hyoungsu Kim; Sung-Il Baek; Tae-Young Ahn; Ok Kyu Park; Jae Sung Son; Yung-Eun Sung; Young-Woon Kim; Zhongwu Wang; Nicola Pinna; Taeghwan Hyeon
• Keywords: MRI contrast agent; XANES

Lamellar structured ultrathin manganese oxide nanoplates have been synthesized from thermal decomposition of manganese(II) acetylacetonate in the presence 2,3-dihydroxynaphthalene, which promoted two-dimensional (2-D) growth by acting not only as a strongly binding surfactant but also structure-directing agent. Ultrathin with thickness about 1 nm were assembled into lamellar structure, and width could be controlled 8 to 70 using various coordinating solvents. X-ray absorption near-edge structure (XANES) spectra at Mn K edge clearly showed that are mainly composed Mn(II) species octahedral symmetry. These hydrophobic ligand-exchanged amine-terminated poly(ethyleneglycol) generate water-dispersible applied T1 contrast agents for magnetic resonance imaging (MRI). They exhibited very high longitudinal relaxivity (r1) value up 5.5 mM–1s–1 derived their concentration ions exposed on surface, strong enhancement vitro vivo MR images was observed low dose.