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A smart magnetic resonance imaging contrast agent responsive to adenosine based on a DNA aptamer-conjugated gadolinium complex.

ABSTRACT: We report a general strategy for developing a smart MRI contrast agent for the sensing of small molecules such as adenosine based on a DNA aptamer that is conjugated to a Gd compound and a protein streptavidin. The binding of adenosine to its aptamer results in the dissociation of the Gd compound from the large protein, leading to decreases in the rotational correlation time and thus change of MRI contrast.

SUBMITTER: Xu W

PROVIDER: S-EPMC3298773 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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A smart magnetic resonance imaging contrast agent responsive to adenosine based on a DNA aptamer-conjugated gadolinium complex.

Xu Weichen W Lu Yi Y

Chemical communications (Cambridge, England) 20110322 17

We report a general strategy for developing a smart MRI contrast agent for the sensing of small molecules such as adenosine based on a DNA aptamer that is conjugated to a Gd compound and a protein streptavidin. The binding of adenosine to its aptamer results in the dissociation of the Gd compound from the large protein, leading to decreases in the rotational correlation time and thus change of MRI contrast. ...[more]

PMID: 21424019

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