Poly(amidoamine) Dendrimer Based MRI Contrast Agents Exhibiting Enhanced Relaxivities Derived via Metal Preligation Techniques

详细信息    查看全文

• 作者：Kido Nwe ; L. Henry Bryant ; Jr. ; Martin W. Brechbiel
• 刊名：Bioconjugate Chemistry
• 出版年：2010
• 出版时间：June 16, 2010
• 年：2010
• 卷：21
• 期：6
• 页码：1014-1017
• 全文大小：117K
• 年卷期：v.21,no.6(June 16, 2010)
• ISSN：1520-4812

文摘

This report presents the preparation and characterization of three [Gd-C-DOTA]up>−1up>−dendrimer assemblies by way of analysis, NMRD spectroscopy, and photon correlation spectroscopy (PCS). The metal−ligand chelates were preformed in alcohol media prior to conjugation to generation 4, 5, and 6 PAMAM dendrimers. The dendrimer-based agents were purified by Sephadex G-25 column chromatography. The combustion analysis, SE-HPLC, and UV−vis data indicated chelate to dendrimer ratios of 28:1, 61:1 and 115:1, respectively. Molar relaxivity measured at pH 7.4, 22 °C, and 3 T (29.6, 49.8, and 89.1 mMup>−1up> sup>−1up>) indicated the viability of conjugates as MRI contrast agents. 1/Tub>1ub> NMRD profiles were measured at 23 °C and indicated that at 22 MHz the 1/Tub>1ub> reached a plateau at 60, 85, and 140 mMup>−1up> sup>−1up> for the generation 4, 5, and 6 dendrimer conjugates, respectively. The PCS data showed the respective sizes of 5.2, 6.5, and 7.8 nm for G-4, 5, and 6 conjugates.