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Updated: Mar 16, 2026

Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging
Published on: December 4, 2016
Effect of ionic interaction between a hyperpolarized magnetic resonance chemical probe and a gadolinium contrast
Yoichi Takakusagi1, Kaori Inoue1, Tatsuya Naganuma2
1Incubation Center for Advanced Medical Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Abstract:
In hyperpolarization of (13)C-enriched magnetic resonance chemical probes in the solid-state, a trace amount of gadolinium (Gd) contrast agent can be used to maximize polarization of the (13)C nuclear spins. Here, we report systematic measurement of the spin-lattice relaxation time (T1) and enhancement level of (13)C-enriched chemical probes in the presence of various Gd contrast agents in the liquid-state after dissolution. Using two different (13)C probes having opposite electric charges at neutral pH, we clearly show the T1 of hyperpolarized (13)C was barely affected by the use of a Gd complex that displays repulsive interaction with the (13)C probe in solution, whilst T1 was drastically shortened when there was ionic attraction between probe and complex.
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