Wearable sensors promise to transform human understanding of body state. However, despite many wearable sensor modalities that exist, few demonstrate the raw capabilities required for many emerging healthcare applications—passivity (and microelectronics‐free), wireless readout, long‐term operation, and specificity. Hydrogel‐interlayer radio‐frequency resonators are demonstrated as a versatile platform for passive and wireless biosensing. Fabricated using a simple vinyl cutter, the base resonator is composed of unanchored, broad‐side coupled coils interceded by multifunctional hydrogels—such resonators are tuned to be sensitive to specific analytical or physical signals by modifying hydrogel composition. These resonators are transformed into near‐field communication (NFC) sensor circuits through the simple attachment of an LED. These enable direct quantification of sensor state by cellphone and eye with no specialized electronics required. Resonator arrays are finally fused with silicone to form soft, wireless sensor skins that enable co‐readout of analytical to physical signals while molded to human subjects. Such low‐cost, accessible platforms can integrate with environments in transformative ways, enabling new applications in wireless sensing.

中文翻译：

---

多功能水凝胶夹层 RF/NFC 谐振器作为无源和无线生物传感的多功能平台

可穿戴传感器有望改变人类对身体状态的理解。然而，尽管存在许多可穿戴传感器模式，但很少有人能够展示许多新兴医疗保健应用所需的原始功能——无源性（和无微电子）、无线读出、长期操作和特异性。水凝胶夹层射频谐振器被证明是用于无源和无线生物传感的多功能平台。使用简单的乙烯基切割器制造，基础谐振器由未锚定的宽边耦合线圈组成，中间有多功能水凝胶——通过修改水凝胶成分，这种谐振器被调整为对特定的分析或物理信号敏感。这些谐振器通过简单的 LED 连接转换为近场通信 (NFC) 传感器电路。这些可以通过手机和眼睛直接量化传感器状态，而无需专门的电子设备。谐振器阵列最终与硅树脂融合，形成柔软的无线传感器外壳，可以在对人体进行模塑的同时对物理信号的分析进行共同读出。这种低成本、可访问的平台可以以变革性的方式与环境集成，从而实现无线传感中的新应用。