Magnetic resonance identification tags for ultra-flexible electrodes
Eminhan Özil1,2, Peter Gombkoto1,2, Athina Apostolelli1,3
1Neurotechnology Group, Institute of Neuroinformatics, Department of Information Technology and Electrical Engineering, ETH Zurich and University of Zurich, Zurich, Switzerland.
Nature Communications
|April 28, 2026
Summary
We developed novel magnetic resonance identification (MRI) tags for ultra-flexible electrodes, enabling precise 3D localization in the brain. This breakthrough improves neuroprosthetics by accurately mapping electrode positions for signal assignment.
Area of Science:
- Neuroscience
- Biomedical Engineering
- Materials Science
Background:
- Ultra-flexible electrodes offer superior biocompatibility for future neuroprosthetics.
- Accurate localization of implanted electrodes is crucial for assigning neural signals to specific brain structures.
Purpose of the Study:
- To develop a method for precise 3D localization of ultra-flexible electrode bundles in the brain.
- To enable accurate anatomical positioning of individual electrodes for neuroprosthetic applications.
Main Methods:
- Developed magnetic resonance identification (MRID)-tags with unique MRI-barcodes patterned onto electrode fibers using superparamagnetic iron-oxide nanoparticles.
- Utilized dot-matrix nanoparticle coating technique for barcode generation.
- Performed chronic in vivo testing in freely-moving rats.
Main Results:
- Achieved accurate 3D reconstruction of electrode bundle trajectories and individual electrode positions.
- Localized individual electrodes with a mean accuracy of 95 μm.
- Demonstrated high long-term recording stability with mean single-unit signal-to-noise ratios up to 20.
Conclusions:
- MRID-tagged ultra-flexible electrodes provide precise anatomical localization for neuroprosthetic applications.
- This technology enhances the ability to assign neural signals to specific brain structures.
- The developed method ensures high recording stability and accuracy for long-term neural interfacing.
