Abstract
The implantable neural probe for simultaneous recording of various brain signals is one of the key technologies for neurological science and clinics that is yet to be broken through. Here, we introduce an implantable neural probe with integrated carbon nanotube field-effect transistors which is able to perform multimodal recording of electrical and chemical signals of the brain under magnetic resonance imaging (MRI). We demonstrate here a simultaneous measurement of an electrophysiological signal with high signal-to-noise ratio up to 40.34 dB and calcium concentration with a detection limit down to 0.47 nM. We use our neural probes to detect neural activity in rats and results reveal that changes in Ca²⁺ concentration occur concurrently with the epileptiform local field potential events, providing an alternative method for accurate detection of epilepsy. Our work may provide a powerful means for the future studies of brain and holds great potential for practical diagnostic applications.
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All data supporting the findings of this study are available within the article and its supplementary files. Any additional requests for information can be directed to, and will be fulfilled by, the corresponding authors. Source data are provided with this paper.
Code availability
The custom code used in this study is available on Zenodo under the https://doi.org/10.5281/zenodo.17547948 (2025)55.
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Acknowledgements
Shurong Dong, Gang Pan, Jikui Luo, Shaomin Zhang et al. would like to thank STI2030-Major Projects (No. 2021ZD0200401). Shurong Dong would like to thank Zhejiang Province high level talent special support plan (No. 2022R52042), Zhejiang Province Key R & D programs (No. 2024C03001, No. 2024C03007). Zhen Cao would like to thank Zhejiang Province Leading Geese Plan (No. 2024C03217). Yanlan Yu would like to thank Medical Interdisciplinary Innovation Program 2024, Zhejiang University School of Medicine. The authors would like to express their gratitude to Prof. Tawfique Hasan (Department of Engineering, University of Cambridge, UK) for the collaboration and technical consultations. We also thank Jingyao Chen, Qiong Huang, Chengcheng Zhang, and Yajun Yu from the core facility platform of Zhejiang University School of Medicine for their technical support, and Xu Bin from Zhejiang University 7 T Brain Imaging Research Center for assistance. We further acknowledge Hangzhou Rong brain Technology Co., Ltd. for assisting with the LFP collection, and process engineers from Haijiexing Technology Co., Ltd. (Suzhou, China) for sharing their expertise inlaser internal modification and providing relevant equipment.
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J.X. and S.D. developed the methodology, acquired the data, and wrote the manuscript. L.Z., Y.Y. and F.Z. conducted the animal experiments. S.W. and L.D. performed data analysis. S.Z., L.D. and G.D. contributed to methodology development and manuscript revision. S.D. supervised the project. G.P. and S.D. provided funding and supervised the study. Z.C. contributed to manuscript revision and supervision. J.L., Y.Y.S.H. and L.O. contributed to manuscript revision.
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Xia, J., Zhang, L., Wang, S. et al. Implantable neural probes with monolithically integrated CNTFET arrays for multimodal monitoring. Nat Commun (2025). https://doi.org/10.1038/s41467-025-67535-5
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DOI: https://doi.org/10.1038/s41467-025-67535-5
