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Synthesis and characterization of a redox- and light-sensitive MRI contrast agent.

ABSTRACT: A redox- and light-sensitive, T(1)-weighted magnetic resonance imaging (MRI) contrast agent which tethers a spiropyran(SP)/merocyanine(MC) motif to a Gd-DO3A moiety was synthesized and characterized. When in the dark, the probe is in its MC form which has an r(1) relaxivity of 2.51 mM(-1)s(-1) (60MHz, 37°C). After irradiation with visible light or mixing with NADH, the probe experiences an isomerization and the r(1) relaxivity decreased 18% and 26%, respectively. Additionally, the signal intensity in MRI showed an observable decrease after the compound was mixed with NADH.

SUBMITTER: Tu C

PROVIDER: S-EPMC2678739 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Synthesis and characterization of a redox- and light-sensitive MRI contrast agent.

Tu Chuqiao C Osborne Elizabeth A EA Louie Angelique Y AY

Tetrahedron 20090201 7

A redox- and light-sensitive, T(1)-weighted magnetic resonance imaging (MRI) contrast agent which tethers a spiropyran(SP)/merocyanine(MC) motif to a Gd-DO3A moiety was synthesized and characterized. When in the dark, the probe is in its MC form which has an r(1) relaxivity of 2.51 mM(-1)s(-1) (60MHz, 37°C). After irradiation with visible light or mixing with NADH, the probe experiences an isomerization and the r(1) relaxivity decreased 18% and 26%, respectively. Additionally, the signal intensi ...[more]

PMID: 20126289

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