A University of Oxford‑led team demonstrated that engineered proteins can exhibit optically detected magnetic resonance (ODMR) in living bacterial cells at room temperature, creating the first practical examples of quantum spin resonance in proteins. The engineered protein MagLOV produced signals readable at single‑cell sensitivity, as reported in Nature and related coverage. The work used directed evolution to enhance magneto‑sensitive fluorescent proteins and highlights a path from fundamental quantum effects to biological sensors. Authors noted the breakthrough could enable multimodal, highly sensitive biosensing and potentially new diagnostics, though translation to mammalian systems and clinical applications will require further development.