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Synthesis of an In vivo MRI-detectable Apoptosis Probe
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H2O2-Responsive Organochalcogen-Based Probes for 19F Chemical Shift-Switching MRI.
Chenyu Peng1,2, Hongwu Liu2, Xueqi Wang2
1Department of Radiology, The First Affiliated Hospital of Xiamen University, Xiamen 361003, China.
Analytical Chemistry
|February 10, 2026
Summary
New organochalcogen complexes act as 19F MRI probes for detecting hydrogen peroxide (H2O2). These probes show significant 19F chemical-shift changes, enabling visualization of H2O2-rich disease regions.
Area of Science:
- Chemical Biology
- Medical Imaging
- Reactive Oxygen Species Research
Background:
- Hydrogen peroxide (H2O2) is a reactive oxygen species implicated in various diseases due to its overexpression in metabolically dysregulated cells.
- Developing sensitive and specific methods for H2O2 detection is crucial for understanding and diagnosing related pathologies.
Purpose of the Study:
- To introduce novel organochalcogen-based complexes as 19F MRI probes for H2O2 detection.
- To evaluate the probes' responsiveness to H2O2 through significant 19F chemical-shift changes.
- To demonstrate the potential for visualizing H2O2-rich areas using 19F chemical-shift-switching MRI.
Main Methods:
- Synthesis of organochalcogen complexes featuring trifluoromethylselenide (CF3Se-) and trifluoromethyltelluride (CF3Te-) moieties.
- Investigation of the reaction kinetics and 19F chemical-shift changes upon oxidation with H2O2.
- Application of 19F MRI to visualize H2O2 in vitro and in a living mouse model of inflammation.
Main Results:
- The designed CF3Se- and CF3Te- based probes reacted rapidly with H2O2, yielding large 19F chemical-shift changes (up to 28 and 55 ppm, respectively).
- 19F chemical-shift-switching MRI successfully visualized H2O2-rich regions.
- The Se-based probe demonstrated detectable chemical-shift changes at biologically relevant H2O2 concentrations in a mouse inflammation model.
Conclusions:
- Organochalcogen-based complexes can be effectively utilized as 19F MRI probes for H2O2 detection.
- These probes offer a promising platform for visual imaging of H2O2-related disease states.
- The study establishes a proof-of-concept for developing responsive 19F MRI agents with large chemical-shift readouts.
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