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A responsive europium(III) chelate that provides a direct readout of pH by MRI.

ABSTRACT: A europium(III) DO3A-tris(amide) complex is reported for imaging pH by MRI using ratiometric chemical exchange saturation transfer (CEST) principles. Deprotonation of a single phenolic proton between pH 6 and 7.6 results in an ?5 ppm shift in the water exchange CEST peak that is easily detected by MRI. Collection of two CEST images at two slightly different activation frequencies provides a direct readout of solution pH without the need of a concentration marker.

SUBMITTER: Wu Y

PROVIDER: S-EPMC2951490 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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A responsive europium(III) chelate that provides a direct readout of pH by MRI.

Wu Yunkou Y Soesbe Todd C TC Kiefer Garry E GE Zhao Piyu P Sherry A Dean AD

Journal of the American Chemical Society 20101001 40

A europium(III) DO3A-tris(amide) complex is reported for imaging pH by MRI using ratiometric chemical exchange saturation transfer (CEST) principles. Deprotonation of a single phenolic proton between pH 6 and 7.6 results in an ∼5 ppm shift in the water exchange CEST peak that is easily detected by MRI. Collection of two CEST images at two slightly different activation frequencies provides a direct readout of solution pH without the need of a concentration marker. ...[more]

PMID: 20853833

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