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A pH-Responsive MRI Agent that Can Be Activated Beyond the Tissue Magnetization Transfer Window.

ABSTRACT: A terbium-based complex that displays a water exchange CEST resonance well outside the normal magnetization transfer (MT) frequency range of tissues provides a direct readout of pH values by MRI. Deprotonation of the phenolic proton in this complex results in a frequency shift of 56?ppm in a bound water molecule exchange peak between pH?5 and 8. This allows direct imaging of pH without prior knowledge of the agent concentration and with essentially no interference from the tissue MT signal.

SUBMITTER: Wang X

PROVIDER: S-EPMC4657548 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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A pH-Responsive MRI Agent that Can Be Activated Beyond the Tissue Magnetization Transfer Window.

Wang Xiaojing X Wu Yunkou Y Soesbe Todd C TC Yu Jing J Zhao Piyu P Kiefer Garry E GE Sherry A Dean AD

Angewandte Chemie (International ed. in English) 20150611 30

A terbium-based complex that displays a water exchange CEST resonance well outside the normal magnetization transfer (MT) frequency range of tissues provides a direct readout of pH values by MRI. Deprotonation of the phenolic proton in this complex results in a frequency shift of 56 ppm in a bound water molecule exchange peak between pH 5 and 8. This allows direct imaging of pH without prior knowledge of the agent concentration and with essentially no interference from the tissue MT signal. ...[more]

PMID: 26096197

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