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Copper(ii) complexes for cysteine detection using 19F magnetic resonance.

ABSTRACT: Cysteine plays an essential role in maintaining cellular redox homeostasis and perturbations in cysteine concentration are associated with cardiovascular disease, liver disease, and cancer. 19F MRI is a promising modality for detecting cysteine in biology due to its high tissue penetration and negligible biological background signal. Herein we report fluorinated macrocyclic copper complexes that display a 19F NMR/MRI turn-on response following reduction of the Cu(ii) complexes by cysteine. The reactivity with cysteine was studied by monitoring the appearance of a robust diamagnetic 19F signal following addition of cysteine in conjunction with UV-vis and EPR spectroscopies. Importantly, complexes with -CH2CF3 tags display good water solubility. Studies with this complex in HeLa cells demonstrate the applicability of these probes to detect cysteine in complex biological environments.

SUBMITTER: Enriquez JS

PROVIDER: S-EPMC6242275 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Copper(ii) complexes for cysteine detection using 19F magnetic resonance.

Enriquez José S JS Yu Meng M Bouley Bailey S BS Xie Da D Que Emily L EL

Dalton transactions (Cambridge, England : 2003) 20181001 42

Cysteine plays an essential role in maintaining cellular redox homeostasis and perturbations in cysteine concentration are associated with cardiovascular disease, liver disease, and cancer. 19F MRI is a promising modality for detecting cysteine in biology due to its high tissue penetration and negligible biological background signal. Herein we report fluorinated macrocyclic copper complexes that display a 19F NMR/MRI turn-on response following reduction of the Cu(ii) complexes by cysteine. The r ...[more]

PMID: 30303220

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