Magnetic resonance control of spin-correlated radical pair dynamics in vivo
Article Meta
Article Date: 18 March 2026
Article URL: https://www.nature.com/articles/s41586-026-10282-4
Article Image: (none provided)
Summary
This Nature paper demonstrates direct magnetic resonance control of spin-correlated radical pair dynamics inside a living animal. The authors engineered and used a bespoke loop-gap resonator and radio-frequency apparatus to drive and read out magnetic-field effects (MFEs) and radio-frequency-driven magnetic resonance (RYDMR) in transgenic Caenorhabditis elegans expressing the red fluorescent protein mScarlet. Optical excitation (blue and green light) generates radical pairs involving flavin (FMN) or reduced protein chromophores; applying static and RF magnetic fields modulates fluorescence via spin dynamics. Complementary in vitro spectroscopy, absorption and EPR measurements support the spin-radical interpretation. Data and analysis code are available on Zenodo.
Key Points
- First demonstration of magnetic resonance control of spin-correlated radical-pair dynamics in vivo (in transgenic C. elegans expressing mScarlet).
- Experimental setup: loop-gap resonator (LGR), Helmholtz coils for static fields, and RF driving at roughly 444 MHz with B1 on the order of 0.1–0.2 mT.
- Optical protocol uses blue (≈450 nm) and green/red (≈520–561 nm) excitation to generate and probe radical pairs; fluorescence changes reveal MFEs and RYDMR signatures.
- In vitro mScarlet–FMN and mScarlet–sodium dithionite experiments, plus CW X-band EPR, corroborate the presence of photogenerated radicals and their magnetic sensitivity.
- Data and custom analysis code are deposited on Zenodo (DOI provided in the paper); crystal structure reference for mScarlet (PDB 5LK4) is cited.
- Potential implications: advances in magnetoreception research, quantum biology, bio-compatible quantum sensing and engineered fluorescent-protein spin qubits.
- Authors note a provisional patent related to mutant ASLOV2 domains; funding and contributions are listed in the paper.
Content summary
The authors built a time-resolved MFE and magnetic-resonance spectroscopy rig centred on a loop-gap resonator to place small living samples close to a controlled RF field. They used transgenic C. elegans expressing mScarlet to report changes in fluorescence that depend on the singlet–triplet interconversion of photogenerated radical pairs. By applying static magnetic fields (both parallel and perpendicular to the RF) and tuned RF drives, they observe reproducible changes in fluorescence (MFE and RYDMR) that match fits to spin-chemistry models. Supporting experiments in solution (mScarlet with FMN or reducing agents) plus absorption and EPR measurements provide chemical and spectroscopic evidence for radical species and for their magnetic resonance behaviour.
Repeated experiments across multiple nematode samples and independent in vitro measurements strengthen the interpretation. The work includes thorough methods, extended data figures showing spatial maps of MFEs and RYDMR amplitudes in nematodes, and numerical simulations of spin dynamics. Raw data and the analysis code are openly available on Zenodo.
Context and relevance
This study bridges spin chemistry and living systems by showing that radio-frequency magnetic resonance can modulate radical-pair spin dynamics in an intact animal and that this modulation is optically detectable. It sits at the intersection of magnetoreception research, spin-driven photochemistry and nascent quantum-biology/quantum-sensing applications. If you follow magnetic-field effects in biology, engineered fluorescent-protein qubits, or development of bio-compatible quantum sensors, this is a pivotal experimental milestone: it moves control of spin chemistry from isolated samples into living tissue.
Author style
Punchy: the paper reads like a technical tour de force — custom hardware, clear optical readouts and multiple spectroscopic cross-checks. The authors emphasise novelty and potential applications; reading the full methods and extended data is worthwhile if you care about reproducing or building on this apparatus.
Why should I read this?
Short answer: because this is the kind of experiment that sounds like sci‑fi — tuning spin chemistry inside a living creature with radio waves — and they actually did it. If you work on magnetoreception, quantum biology, fluorescent-protein sensors or want new routes to bio-compatible quantum sensing, this paper saves you time: it’s the demonstration you’ll cite and build from.