Continuous monitoring of arterial blood pressure (BP) in non-clinical (ambulatory) settings is essential for understanding numerous health conditions, including cardiovascular diseases. Besides their importance in medical diagnosis, ambulatory BP monitoring platforms can advance disease correlation with individual behaviour, daily habits and lifestyle, potentially enabling analysis of root causes, prognosis and disease prevention. Although conventional ambulatory BP devices exist, they are uncomfortable, bulky and intrusive. Here we introduce a wearable continuous BP monitoring platform that is based on electrical bioimpedance and leverages atomically thin, self-adhesive, lightweight and unobtrusive graphene electronic tattoos as human bioelectronic interfaces. The graphene electronic tattoos are used to monitor arterial BP for >300 min, a period tenfold longer than reported in previous studies. The BP is recorded continuously and non-invasively, with an accuracy of 0.2 ± 4.5 mm Hg for diastolic pressures and 0.2 ± 5.8 mm Hg for systolic pressures, a performance equivalent to Grade A classification.
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Nano-Micro Letters Open Access 09 August 2022
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The complete dataset supporting the findings of this study is available via the PhysioNet data repository at https://doi.org/10.13026/qcc8-n557. The associated preprocessed raw data are available and can be shared with interested parties upon reasonable request. Source data are provided with this paper.
The machine learning algorithm is publicly available via GitHub at https://github.com/TAMU-ESP/Graphene_BP. The custom codes used for data visualization are available from the corresponding authors upon request.
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The work was supported in part by the Office of Naval Research under grant number N00014-18-1-2706, the Temple Foundation Endowed Professorship, the National Science Foundation under grant number 1738293 and the National Institute of Health under grant number 1R01EB028106. R.J. acknowledges useful discussions with the former founding director of the National Institute of Biomedical Imaging and Bioengineering (NIBIB) at the NIH, R. I. Pettigrew. We acknowledge J. Wozniak at the Texas Advanced Computing Center (TACC) at The University of Texas at Austin (http://www.tacc.utexas.edu) for creating Fig. 1a. The authors have permission to use and publish the image.
R.J. and B.I. filed a patent (US 2020/0138303 titled ‘System and method for cuff-less blood pressure monitoring’) related to this research; this patent is licensed to SpectroBeat LLC.
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Supplementary Figs. 1–26, Tables 1–10 and Notes 1–9.
Mechanical stability of graphene electronic tattoos.
Batch transfer of GETs.
Live recording of BP with GETs number 1.
Live recording of BP with GETs number 2.
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Kireev, D., Sel, K., Ibrahim, B. et al. Continuous cuffless monitoring of arterial blood pressure via graphene bioimpedance tattoos. Nat. Nanotechnol. 17, 864–870 (2022). https://doi.org/10.1038/s41565-022-01145-w
Nano-Micro Letters (2022)