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Synthesis and Comparative Evaluation of Photoswitchable Magnetic Resonance Imaging Contrast Agents.

ABSTRACT: A series of spiropyran (SP)-based magnetic resonance imaging (MRI) contrast agents have been synthesized and evaluated for changes in relaxivity resulting from irradiation with visible light. Both electron-donating and electron-withdrawing substituents were appended to the SP ring in order to study the electronic effects on the photochromic and relaxivity properties of these photoswitchable MRI contrast agents. Photoswitches lacking an electron-withdrawing substituent isomerize readily between the merocyanine and SP forms, while the addition of a nitro group prevents this process. Complexes capable of isomerizing were demonstrated to effect a change in the relaxivity of the appended gadolinium complex.

SUBMITTER: Gao M

PROVIDER: S-EPMC7315594 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Synthesis and Comparative Evaluation of Photoswitchable Magnetic Resonance Imaging Contrast Agents.

Gao Mingchun M Shen Bowen B Zhou Junhan J Kapre Rohan R Louie Angelique Y AY Shaw Jared T JT

ACS omega 20200611 24

A series of spiropyran (SP)-based magnetic resonance imaging (MRI) contrast agents have been synthesized and evaluated for changes in relaxivity resulting from irradiation with visible light. Both electron-donating and electron-withdrawing substituents were appended to the SP ring in order to study the electronic effects on the photochromic and relaxivity properties of these photoswitchable MRI contrast agents. Photoswitches lacking an electron-withdrawing substituent isomerize readily between t ...[more]

PMID: 32596613

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