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Ratiometric pH-Responsive ¹⁹F Magnetic Resonance Imaging Contrast Agents Based on Hydrazone Switches.

ABSTRACT: Hydrazone-based molecular switches serve as efficient ratiometric pH-sensitive agents that can be tracked with ¹⁹F NMR/MRI and ¹H NMR. Structural changes induced between pH 3 and 4 lead to signal appearance and disappearance at ¹H and ¹⁹F NMR spectra allowing ratiometric pH measurements. The most pronounced are resonances of the CF₃ group shifted by 1.8 ppm with ¹⁹F NMR and a hydrazone proton shifted by 2 ppm with ¹H NMR.

SUBMITTER: Janasik D

PROVIDER: S-EPMC8892427 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Ratiometric pH-Responsive 19F Magnetic Resonance Imaging Contrast Agents Based on Hydrazone Switches.

Janasik Dawid D Jasiński Krzysztof K Węglarz Władysław P WP Nemec Ivan I Jewula Pawel P Krawczyk Tomasz T

Analytical chemistry 20220214 8

Hydrazone-based molecular switches serve as efficient ratiometric pH-sensitive agents that can be tracked with 19F NMR/MRI and 1H NMR. Structural changes induced between pH 3 and 4 lead to signal appearance and disappearance at 1H and 19F NMR spectra allowing ratiometric pH measurements. The most pronounced are resonances of the CF3 group shifted by 1.8 ppm with 19F NMR and a hydrazone proton shifted by 2 ppm with 1H NM ...[more]

PMID: 35156816

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