Wearable electroenzymatic sensors enable monitoring of clinically informative biomolecules in epidermally retrievable biofluids. Conventional wearable enzymatic sensors utilize Prussian Blue (a redox mediator) to achieve selectivity against electroactive interferents. However, the use of Prussian Blue presents fundamental challenges including: 1) the susceptibility of the sensor response to dynamic concentration variation of ionic species and 2) the poor operational stability due to the degradation of its framework. As an alternative wearable electroenzymatic sensor development methodology to bypass the aforementioned limitations, a mediator‐free sensing interface is devised, comprising of a coupled platinum nanoparticle/multiwall carbon nanotube layer and a permselective membrane. The interface is adapted to develop sensors targeting glucose, lactate, and choline (as examples of informative metabolites and nutrients), showing high degrees of sensitivity, selectivity (against a wide panel of naturally present and diverse interfering species), stability (<6.5% signal drift over 20 h operation), and reliability of sensing operation in sweat samples. By integration within a readout board, a wireless sample‐to‐answer system is realized for on‐body sweat biomarker analysis. This methodology can be adapted to target a wide panel of biomarkers in various biofluids, introducing a new sensor development direction for personal health monitoring.
Wearable wireless passive sensors are powerful potential building blocks of modern body area networks. However, these sensors are often hampered by numerous issues including restrictive read‐out distances due to near‐field coupling, fundamental tradeoffs in size/spectral performance, and unreliable sensor tracking during activity. Here, to overcome such issues implementing wearable sensing systems exhibiting coupled magnetic resonances are demonstrated. This approach is utilized to augment wireless telemetry from fully wearable, passive (zero electronics) resonator chains. Secondary receiver coils are integrated into fabric or skin to facilitate augmented read‐out from epidermal sweat, moisture, or pressure sensors—herein exhibiting enhanced read‐out range, relaxed constraints in sensor size (sensor spectral response becomes untethered from size) and reader‐sensor orientation. Unlike existing schemes, this readout method enables decoupled co‐readout of the sensor's distance and status, employed here for co‐measurement with human respiration. This type of decoupled readout can help compensate for movements that are so common in wearable monitoring. Simple to implement and requiring no microelectronics, this scheme streamlines into existing, body‐worn passive wireless telemetric systems with minimal modification.
more » « less- NSF-PAR ID:
- 10452718
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 6
- Issue:
- 4
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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