Multifunctional porous soft composites for bimodal wearable cardiac monitors

Abstract

Wearable heart monitors are crucial for early diagnosis and treatment of heart diseases in non‐clinical settings. However, their long‐term applications require skin‐interfaced materials that are ultrasoft, breathable, antibacterial, and possess robust, enduring on‐skin adherence—features that remain elusive. Here, we have developed multifunctional porous soft composites that meet all these criteria for skin‐interfaced bimodal cardiac monitoring. The composite consists of a bilayer structure featuring phase‐separated porous elastomer and slot‐die‐coated biogel. The porous elastomer ensures ultrasoftness, breathability, ease of handling, and mechanical integrity, while the biogel enables long‐term on‐skin adherence. Additionally, we incorporated ε‐polylysine in the biogel to offer antibacterial properties. Also, the conductive biogel embedded with silver nanowires was developed for use in electrocardiogram sensors to reduce contact impedance and ensure high‐fidelity recordings. Furthermore, we assembled a bimodal wearable cardiac monitoring system that demonstrates high‐fidelity recordings of both cardiac electrical (electrocardiogram) and mechanical (seismocardiogram) signals over a 14‐day testing period.