Rose Daniel P, Ratterman Michael E, Griffin Daniel K, Hou Linlin, Kelley-Loughnane Nancy, Naik Rajesh R, Hagen Joshua A, Papautsky Ian, Heikenfeld Jason C
IEEE Trans Biomed Eng. 2015 Jun;62(6):1457-65. doi: 10.1109/TBME.2014.2369991. Epub 2014 Nov 11.
Wearable digital health devices are dominantly found in rigid form factors such as bracelets and pucks. An adhesive radio-frequency identification (RFID) sensor bandage (patch) is reported, which can be made completely intimate with human skin, a distinct advantage for chronological monitoring of biomarkers in sweat. In this demonstration, a commercial RFID chip is adapted with minimum components to allow potentiometric sensing of solutes in sweat, and surface temperature, as read by an Android smartphone app with 96% accuracy at 50 mM Na(+) (in vitro tests). All circuitry is solder-reflow integrated on a standard Cu/polyimide flexible-electronic layer including an antenna, but while also allowing electroplating for simple integration of exotic metals for sensing electrodes. Optional paper microfluidics wick sweat from a sweat porous adhesive allowing flow to the sensor, or the sensor can be directly contacted to the skin. The wearability of the patch has been demonstrated for up to seven days, and includes a protective textile which provides a feel and appearance similar to a standard Band-Aid. Applications include hydration monitoring, but the basic capability is extendable to other mM ionic solutes in sweat (Cl(-), K(+), Mg(2+), NH4(+), and Zn(2+)). The design and fabrication of the patch are provided in full detail, as the basic components could be useful in the design of other wearable sensors.
可穿戴数字健康设备主要以刚性外形出现，如手环和圆盘。本文报道了一种粘性射频识别（RFID）传感器绷带（贴片），它能与人体皮肤完全贴合，这对于按时间顺序监测汗液中的生物标志物来说是一个显著优势。在本演示中，对一款商用RFID芯片进行了最少组件适配，以实现对汗液中溶质和表面温度的电位传感，通过安卓智能手机应用读取数据，在50 mM Na⁺（体外测试）时准确率达96%。所有电路通过回流焊集成在包括天线的标准铜/聚酰亚胺柔性电子层上，同时还允许电镀，以便简单集成用于传感电极的特殊金属。可选的纸质微流体从汗液多孔粘合剂中吸取汗液并流向传感器，或者传感器可直接与皮肤接触。该贴片的可穿戴性已得到长达七天的验证，并且包括一种防护织物，其触感和外观与标准创可贴相似。应用包括水合作用监测，但基本功能可扩展到汗液中的其他毫摩尔离子溶质（Cl⁻、K⁺、Mg²⁺、NH₄⁺和Zn²⁺）。文中详细介绍了贴片的设计与制造过程，因为其基本组件可能对其他可穿戴传感器的设计有用。
