Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Continuous cuffless monitoring of arterial blood pressure via graphene bioimpedance tattoos

Abstract

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.

Your institute does not have access to this article

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Fig. 1: Illustration of Z-BP measurement modality.
Fig. 2: Correlation between arterial BP and bioimpedance.
Fig. 3: Graphene Z-BP measurement results from the HGCP routine.
Fig. 4: Graphene Z-BP model training and performance evaluation.

Data availability

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.

Code availability

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.

References

  1. Jennings, J. R., Muldoon, M. F., Allen, B., Ginty, A. T. & Gianaros, P. J. Cerebrovascular function in hypertension: does high blood pressure make you old? Psychophysiology 58, 1–17 (2021).

    Article  Google Scholar 

  2. Shaffer, F., McCraty, R. & Zerr, C. L. A healthy heart is not a metronome: an integrative review of the heartas anatomy and heart rate variability. Front. Psychol. 5, 1040 (2014).

    Article  Google Scholar 

  3. Kwon, Y. et al. Blood pressure monitoring in sleep: time to wake up. Blood Press. Monit. 25, 61–68 (2020).

    Article  Google Scholar 

  4. Magder, S. The meaning of blood pressure. Crit. Care 22, 257 (2018).

    CAS  Article  Google Scholar 

  5. Benjamin, E. J. et al. Heart disease and stroke statistics—2019 update: a report from the American Heart Association. Circulation 139, e556–e528 (2019).

    Article  Google Scholar 

  6. Flint, A. C. et al. Effect of systolic and diastolic blood pressure on cardiovascular outcomes. N. Engl. J. Med. 381, 243–251 (2019).

    Article  Google Scholar 

  7. Kario, K. Management of hypertension in the digital era. Hypertension 76, 640–650 (2020).

    CAS  Article  Google Scholar 

  8. Carey, R. M., Muntner, P., Bosworth, H. B. & Whelton, P. K. Prevention and control of hypertension. J. Am. Coll. Cardiol. 72, 1278–1293 (2018).

    Article  Google Scholar 

  9. Kario, K. et al. Morning home blood pressure is a strong predictor of coronary artery disease: the honest study. J. Am. Coll. Cardiol. 67, 1519–1527 (2016).

    Article  Google Scholar 

  10. Al Ghorani, H., Kulenthiran, S., Lauder, L., Böhm, M. & Mahfoud, F. Hypertension trials update. J. Hum. Hypertens. 35, 398–409 (2021).

    Article  Google Scholar 

  11. Marrone, O. & Bonsignore, M. R. Blood-pressure variability in patients with obstructive sleep apnea: current perspectives. Nat. Sci. Sleep. 10, 229–242 (2018).

    Article  Google Scholar 

  12. Salazar, M. R. et al. Nocturnal hypertension in high-risk mid-pregnancies predict the development of preeclampsia/eclampsia. J. Hypertens. 37, 182–186 (2018).

  13. Stergiou, G. S. et al. A universal standard for the validation of blood pressure measuring devices. Hypertension 71, 368–374 (2018).

    CAS  Article  Google Scholar 

  14. Bartels, K., Esper, S. A. & Thiele, R. H. Blood pressure monitoring for the anesthesiologist. Anesth. Analg. 122, 1866–1879 (2016).

    CAS  Article  Google Scholar 

  15. Vischer, A. S. & Burkard, T. Principles of blood pressure measurement – current techniques, office vs ambulatory blood pressure measurement. Adv. Exp. Med. Biol. 956, 85–96 (2016).

    Article  Google Scholar 

  16. Siu, A. L. et al. Screening for high blood pressure in adults: U.S. preventive services task force recommendation statement. Ann. Intern. Med. 163, 778–786 (2015).

    Article  Google Scholar 

  17. Jeong, I. C., Bychkov, D. & Searson, P. C. Wearable devices for precision medicine and health state monitoring. IEEE Trans. Biomed. Eng. 66, 1242–1258 (2019).

    Article  Google Scholar 

  18. Li, R., Liang, N., Bu, F. & Hesketh, T. The effectiveness of self-management of hypertension in adults using mobile health: systematic review and meta-analysis. JMIR mHealth uHealth 8, e17776 (2020).

    Article  Google Scholar 

  19. \Asayama, K., Ohkubo, T. & Imai, Y. In-office and out-of-office blood pressure measurement. J. Hum. Hypertens. https://doi.org/10.1038/s41371-021-00486-8 (2021).

  20. Pandit, J. A., Lores, E. & Batlle, D. Cuffless blood pressure monitoring. Clin. J. Am. Soc. Nephrol. 15, 1531–1538 (2020).

    Article  Google Scholar 

  21. Wang, C. et al. Monitoring of the central blood pressure waveform via a conformal ultrasonic device. Nat. Biomed. Eng. 2, 687–695 (2018).

    Article  Google Scholar 

  22. Wang, C. et al. Continuous monitoring of deep-tissue haemodynamics with stretchable ultrasonic phased arrays. Nat. Biomed. Eng. 5, 749–758 (2021).

    CAS  Article  Google Scholar 

  23. Luo, N. et al. Flexible piezoresistive sensor patch enabling ultralow power cuffless blood pressure measurement. Adv. Funct. Mater. 26, 1178–1187 (2016).

    CAS  Article  Google Scholar 

  24. Kim, J. et al. Soft wearable pressure sensors for beat-to-beat blood pressure monitoring. Adv. Healthc. Mater. 8, 1–9 (2019).

    Article  CAS  Google Scholar 

  25. Yang, S., Zhang, Y., Cho, S. Y., Correia, R. & Morgan, S. P. Non-invasive cuff-less blood pressure estimation using a hybrid deep learning model. Opt. Quantum Electron. 53, 1–20 (2021).

    Article  CAS  Google Scholar 

  26. Elgendi, M. et al. The use of photoplethysmography for assessing hypertension. npj Digit. Med. 2, 1–11 (2019).

    Article  Google Scholar 

  27. Chang, Y. H., Huang, K. C., Yang, C. C. & Tsai, H. Y. Evaluation of absorbed light dose in human skin tissue during Light Therapy by 630nm LED light. In 2015 IEEE 12th International Conference on Networking, Sensing and Control 394–398 (IEEE, 2015); https://doi.org/10.1109/ICNSC.2015.7116069

  28. Safar, M. E. & Boudier, H. S. Vascular development, pulse pressure, and the mechanisms of hypertension. Hypertension 46, 205–209 (2005).

    CAS  Article  Google Scholar 

  29. Sel, K. et al. Electrical characterization of graphene-based e-tattoos for bio-impedance-based physiological sensing. In 2019 IEEE Biomedical Circuits and Systems Conference 1–4 (IEEE, 2019); https://doi.org/10.1109/BIOCAS.2019.8919003

  30. Sel, K., Osman, D. & Jafari, R. Non-invasive cardiac and respiratory activity assessment from various human body locations using bioimpedance. IEEE Open J. Eng. Med. Biol. 2, 210–217 (2021).

    Article  Google Scholar 

  31. Wang, T. W., Chen, W. X., Chu, H. W. & Lin, S. F. Single-channel bioimpedance measurement for wearable continuous blood pressure monitoring. IEEE Trans. Instrum. Meas. 70, 1–9 (2021).

  32. Kabiri Ameri, S. et al. Graphene electronic tattoo sensors. ACS Nano 11, 7634–7641 (2017).

    CAS  Article  Google Scholar 

  33. Ameri, S. K. et al. Imperceptible electrooculography graphene sensor system for human–robot interface. npj 2D Mater. Appl. 2, 19 (2018).

    Article  CAS  Google Scholar 

  34. Kireev, D. et al. Fabrication, characterization and applications of graphene electronic tattoos. Nat. Protoc. 16, 2395–2417 (2021).

    CAS  Article  Google Scholar 

  35. Ibrahim, B. & Jafari, R. Cuffless blood pressure monitoring from an array of wrist bio-impedance sensors using subject-specific regression models: proof of concept. IEEE Trans. Biomed. Circ. Syst. 13, 1723–1735 (2019).

    Article  Google Scholar 

  36. American National Standards Institute, Association for the Advancement of Medical Instrumentation. ANSI/AAMI ES60601-1:2005/A1:2012, Medical Electrical Equipment Part 1: General Requirements for Basic Safety and Essential Performance (ANSI/AAMI 2012); https://webstore.ansi.org/Standards/AAMI/ansiaamies606012005r2012

  37. Sel, K., Ibrahim, B. & Jafari, R. ImpediBands: body coupled bio-impedance patches for physiological sensing proof of concept. IEEE Trans. Biomed. Circ. Syst. 14, 757–774 (2020).

  38. Webster, J. Medical Instrumentation: Application and Design 4th edn (John Wiley & Sons, 2010).

  39. Miccoli, I., Edler, F., Pfnür, H. & Tegenkamp, C. The 100th anniversary of the four-point probe technique: the role of probe geometries in isotropic and anisotropic systems. J. Phys. Condens. Matter 27, 223201 (2015).

    CAS  Article  Google Scholar 

  40. Brath, P. C. & Eisenach, J. C. Atlas of cardiovascular monitoring. Anesthesiology 93, 312–312 (2000).

    Article  Google Scholar 

  41. Vlachopoulos, C., O’Rourke, M. & Nichols, W. W. McDonald’s Blood Flow in Arteries (CRC, 2011); https://doi.org/10.1201/b13568

  42. Jang, H., Dai, Z., Ha, K.-H., Ameri, S. K. & Lu, N. Stretchability of PMMA-supported CVD graphene and of its electrical contacts. 2D Mater. 7, 014003 (2019).

    Article  CAS  Google Scholar 

  43. Goldstein, D. S. & Cheshire, W. P. Beat-to-beat blood pressure and heart rate responses to the Valsalva maneuver. Clin. Auton. Res. 27, 361–367 (2017).

    Article  Google Scholar 

  44. Johnson, B. D., Sackett, J. R., Schlader, Z. J. & Leddy, J. J. Attenuated cardiovascular responses to the cold pressor test in concussed collegiate athletes. J. Athl. Train. 55, 124–131 (2020).

    Article  Google Scholar 

  45. Byambasukh, O., Snieder, H. & Corpeleijn, E. Relation between leisure time, commuting, and occupational physical activity with blood pressure in 125 402 Adults: the Lifelines cohort. J. Am. Heart Assoc. 9, e014313 (2020).

    Article  Google Scholar 

  46. IEEE Engineering in Medicine and Biology Society IEEE Standard for Wearable, Cuffless Blood Pressure Measuring Devices IEEE 1708-2014 (IEEE, 2014).

  47. Koshimizu, H., Kojima, R. & Okuno, Y. Future possibilities for artificial intelligence in the practical management of hypertension. Hypertens. Res. 43, 1327–1337 (2020).

    Article  Google Scholar 

  48. Herakova, N., Nwobodo, N. H. N., Wang, Y., Chen, F. & Zheng, D. Effect of respiratory pattern on automated clinical blood pressure measurement: an observational study with normotensive subjects. Clin. Hypertens. 23, 15 (2017).

    Article  Google Scholar 

  49. McEniery, C. M., Cockcroft, J. R., Roman, M. J., Franklin, S. S. & Wilkinson, I. B. Central blood pressure: current evidence and clinical importance. Eur. Heart J. 35, 1719–1725 (2014).

    Article  Google Scholar 

  50. Asayama, K. et al. Nocturnal blood pressuremeasured by home devices: Evidence and perspective for clinical application. J. Hypertens. 37, 905–916 (2019).

    CAS  Article  Google Scholar 

  51. Gaffey, A. E., Schwartz, J. E., Harris, K. M., Hall, M. H. & Burg, M. M. Effects of ambulatory blood pressure monitoring on sleep in healthy, normotensive men and women. Blood Press. Monit. 26, 93–101 (2021).

  52. Soleimani, E., Mokhtari-Dizaji, M., Fatouraee, N. & Saberi, H. Assessing the blood pressure waveform of the carotid artery using an ultrasound image processing method. Ultrasonography 36, 144–152 (2017).

    Article  Google Scholar 

  53. Kemmotsu, O. et al. Blood pressure measurement by arterial tonometry in controlled Hypotension. Anesth. Analg. 73, 54–58 (1991).

    CAS  Article  Google Scholar 

  54. Lee, J. Y., Choi, E. Y., Jeong, H. J., Kim, K. H. & Park, J. C. Blood pressure measurement using finger cuff. Conf. Proc. IEEE Eng. Med. Biol. Soc. 7 S, 3575–3577 (2005).

  55. Mazoteras Pardo, V., Losa Iglesias, M. E., López Chicharro, J. & Becerro de Bengoa Vallejo, R. The QardioArm app in the assessment of blood pressure and heart rate: reliability and validity study. JMIR mHealth uHealth 5, e198 (2017).

    Article  Google Scholar 

Download references

Acknowledgements

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.

Author information

Authors and Affiliations

Authors

Contributions

D.K., K.S., R.J. and D.A. conceived the idea of using GET and designed the experiments. B.I. and R.J. designed the instrumentation for bioimpedance acquisition. D.K. fabricated and characterized the GETs. K.S. and B.I. optimized the XL-board. D.K., K.S., B.I. and N.K. performed the BP experiments. B.I. and A.A. developed and utilized the machine learning algorithm. D.K. and K.S. compiled and analysed the data. The manuscript was written with the contributions of all authors. All authors have approved the final version of the manuscript.

Corresponding authors

Correspondence to Roozbeh Jafari or Deji Akinwande.

Ethics declarations

Competing interests

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.

Peer review

Peer review information

Nature Nanotechnology thanks Yingying Zhang and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1–26, Tables 1–10 and Notes 1–9.

Reporting Summary

Supplementary Video 1

Mechanical stability of graphene electronic tattoos.

Supplementary Video 2

Batch transfer of GETs.

Supplementary Video 3

Live recording of BP with GETs number 1.

Supplementary Video 4

Live recording of BP with GETs number 2.

Source data

Source Data Fig. 3

Statistical source data.

Source Data Fig. 4

Statistical source data.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Kireev, D., Sel, K., Ibrahim, B. et al. Continuous cuffless monitoring of arterial blood pressure via graphene bioimpedance tattoos. Nat. Nanotechnol. (2022). https://doi.org/10.1038/s41565-022-01145-w

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1038/s41565-022-01145-w

Further reading

Search

Quick links

Find nanotechnology articles, nanomaterial data and patents all in one place. Visit Nano by Nature Research