Smart healthcare sensor with dual autonomous self-healing, repeatable skin adhesion/detachment, and hydrophilic/hydrophobic Janus surface for aquatic ambulatory electrophysiological monitoring

Smart healthcare sensors (SHSs) belong to a kind of patient-centered diagnostics, which highly revolutionizes traditional healthcare service and attracts great attention. However, widespread application of currently-reported SHSs is severely limited due to their non-ideal mechanical/electrical self-healing performance, too robust/weak skin-adhesion strength, and poor water resistance. A kind of novel film-based SHSs that composed of poly(3-hexylthiophene-2, 5-diyl)/butyl rubber (P3HT/BR), eutectic Gallium-Indium (E-GaIn), and polydimethylsiloxane-P3HT/BR (P-P3HT/BR) were proposed herein and employed for high-performance electrocardiogram (ECG) monitoring. Specifically, viscosity characteristic and low glass transition temperature of BR, hooked chains of P3HT, and encapsulated E-GaIn jointly endowed the SHSs with high mechanical and electrical self-healing efficiencies of 79.62% ± 5.60% and 94.49% ± 5.05%, respectively. Meanwhile, skin adhesion mechanism of the SHSs was mainly relied on Van der Waals force and friction force, thus resulting in a sufficient adhesion or painless detachment with a skin-adhesion strength of 7.00 ± 0.70 kPa. More interestingly, extensive experimental results performed in pigs and humans demonstrated the SHSs achieved ECG monitoring with high accuracy and stable sensitivity underwater, due to the designed hydrophilic/hydrophobic Janus surface. Overall, the as-fabricated SHSs provided an outstanding biopotential monitoring and paved an ascendant way toward personalized healthcare in the new era.