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Updated: May 2, 2026
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Use of Electron Paramagnetic Resonance in Biological Samples at Ambient Temperature and 77 K
Published on: January 11, 2019
9.1K
Quantum Zeno Effect Permits Magnetosensitivity in Lipid Peroxidation despite Fluctuating Inter-Radical Coupling
Matt C J Denton1,2, Daniel R Kattnig1,2
1Living Systems Institute, University of Exeter, Stocker Road, Exeter, Devon EX4 4QD, U.K.
JACS Au
|May 1, 2026
Summary
Magnetic fields influence lipid peroxidation, a key process in aging and disease. Our study shows these effects persist even with strong interactions in biological membranes, suggesting broader potential for magnetosensitivity.
Area of Science:
- Biochemistry
- Physical Chemistry
- Biophysics
Background:
- Lipid peroxidation is an oxidative process central to cellular aging, ferroptosis, and various pathologies, often associated with oxidative stress.
- Growing evidence suggests lipid peroxidation is sensitive to weak magnetic fields, with the radical pair mechanism (RPM) as a proposed explanation.
- Previous RPM studies used simple models, lacking evaluation under biologically realistic conditions with strong inter-radical interactions.
Purpose of the Study:
- To investigate the impact of dynamic inter-radical dipolar coupling on magnetic field sensitivity in lipid peroxidation chain termination reactions.
- To evaluate the efficacy of the radical pair mechanism (RPM) under biologically relevant conditions, considering strong inter-radical interactions.
Main Methods:
- Utilized Brownian dynamics-informed spin dynamics calculations to model the system.
- Investigated the effects of dynamic inter-radical dipolar coupling on magnetic field sensitivity.
- Analyzed the influence of recombination rate constants and spin relaxation mechanisms (g-matrix anisotropy).
Main Results:
- Weak magnetic field effects persist in lipid peroxidation despite strong, fluctuating dipolar interactions, contingent on fast spin-selective radical recombination (quantum Zeno effect).
- Recombination quantum yield shows strong dependence on the recombination rate constant, influencing low-field effects, high-field sensitivity, or magnetic responsiveness.
- At high magnetic fields, g-matrix anisotropy-driven spin relaxation can lead to pronounced magnetosensitivity for fast recombination processes.
Conclusions:
- Magnetic field effects are viable in strongly coupled radical pairs within biological membranes under specific dynamical and kinetic constraints.
- The study highlights potential for broader magnetosensitivity in confined, low-mobility biological environments than predicted by standard RPM models.
- Findings suggest magnetic fields could modulate biological processes like lipid peroxidation, with implications for understanding aging and disease.
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