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Organic radical contrast agents for magnetic resonance imaging.

ABSTRACT: We report a molecular design that provides an intravenously injectable organic radical contrast agent (ORCA) for which the molecular (1)H water relaxivity (r(1)) is ca. 5 mM(-1) s(-1). The ORCA is based on spirocyclohexyl nitroxide radicals and poly(ethylene glycol) chains conjugated to a fourth-generation polypropylenimine dendrimer scaffold. The metal-free ORCA has a long shelf life and provides selectively enhanced magnetic resonance imaging in mice for over 1 h.

SUBMITTER: Rajca A

PROVIDER: S-EPMC3486519 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Organic radical contrast agents for magnetic resonance imaging.

Rajca Andrzej A Wang Ying Y Boska Michael M Paletta Joseph T JT Olankitwanit Arnon A Swanson Michael A MA Mitchell Deborah G DG Eaton Sandra S SS Eaton Gareth R GR Rajca Suchada S

Journal of the American Chemical Society 20120917 38

We report a molecular design that provides an intravenously injectable organic radical contrast agent (ORCA) for which the molecular (1)H water relaxivity (r(1)) is ca. 5 mM(-1) s(-1). The ORCA is based on spirocyclohexyl nitroxide radicals and poly(ethylene glycol) chains conjugated to a fourth-generation polypropylenimine dendrimer scaffold. The metal-free ORCA has a long shelf life and provides selectively enhanced magnetic resonance imaging in mice for over 1 h. ...[more]

PMID: 22974177

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