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Multivalent, high-relaxivity MRI contrast agents using rigid cysteine-reactive gadolinium complexes.

ABSTRACT: MRI contrast agents providing very high relaxivity values can be obtained through the attachment of multiple gadolinium(III) complexes to the interior surfaces of genome-free viral capsids. In previous studies, the contrast enhancement was predicted to depend on the rigidity of the linker attaching the MRI agents to the protein surface. To test this hypothesis, a new set of Gd-hydroxypyridonate based MRI agents was prepared and attached to genetically introduced cysteine residues through flexible and rigid linkers. Greater contrast enhancements were seen for MRI agents that were attached via rigid linkers, validating the design concept and outlining a path for future improvements of nanoscale MRI contrast agents.

SUBMITTER: Garimella PD

PROVIDER: S-EPMC3188312 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Multivalent, high-relaxivity MRI contrast agents using rigid cysteine-reactive gadolinium complexes.

Garimella Praveena D PD Datta Ankona A Romanini Dante W DW Raymond Kenneth N KN Francis Matthew B MB

Journal of the American Chemical Society 20110826 37

MRI contrast agents providing very high relaxivity values can be obtained through the attachment of multiple gadolinium(III) complexes to the interior surfaces of genome-free viral capsids. In previous studies, the contrast enhancement was predicted to depend on the rigidity of the linker attaching the MRI agents to the protein surface. To test this hypothesis, a new set of Gd-hydroxypyridonate based MRI agents was prepared and attached to genetically introduced cysteine residues through flexibl ...[more]

PMID: 21800868

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