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Wearable biosensors for healthcare monitoring

Abstract

Wearable biosensors are garnering substantial interest due to their potential to provide continuous, real-time physiological information via dynamic, noninvasive measurements of biochemical markers in biofluids, such as sweat, tears, saliva and interstitial fluid. Recent developments have focused on electrochemical and optical biosensors, together with advances in the noninvasive monitoring of biomarkers including metabolites, bacteria and hormones. A combination of multiplexed biosensing, microfluidic sampling and transport systems have been integrated, miniaturized and combined with flexible materials for improved wearability and ease of operation. Although wearable biosensors hold promise, a better understanding of the correlations between analyte concentrations in the blood and noninvasive biofluids is needed to improve reliability. An expanded set of on-body bioaffinity assays and more sensing strategies are needed to make more biomarkers accessible to monitoring. Large-cohort validation studies of wearable biosensor performance will be needed to underpin clinical acceptance. Accurate and reliable real-time sensing of physiological information using wearable biosensor technologies would have a broad impact on our daily lives.

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Fig. 1: Biosensor components and the path of biosensor development for wearables.
Fig. 2: Representative examples of wearable biosensors.
Fig. 3: Epidermal biosensors for real-time monitoring of sweat chemistry.
Fig. 4: Epidermal iontophoretic biosensors.
Fig. 5: Tear-based biosensors.
Fig. 6: Saliva-based biosensors.

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Acknowledgements

This work was supported by the Defense Threat Reduction Agency Joint Science and Technology Office for Chemical and Biological Defense (HDTRA 1-16-1-0013). A.S.C. acknowledges funding through NIH NIAAA T32 Training Grant AA013525.

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Kim, J., Campbell, A.S., de Ávila, B.EF. et al. Wearable biosensors for healthcare monitoring. Nat Biotechnol 37, 389–406 (2019). https://doi.org/10.1038/s41587-019-0045-y

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