Hashimoto Yuki, Ishihara Takako, Kuwabara Kei, Amano Tatsuro, Togo Hiroyoshi
NTT Device Innovation Center, NTT Corporation, 3-1, Atsugi 243-0198, Japan.
Laboratory for Exercise and Environmental Physiology, Faculty of Education, Niigata University, Niigata 950-2181, Japan.
Micromachines (Basel). 2022 Apr 6;13(4):575. doi: 10.3390/mi13040575.
Temperature elevation due to global warming increases the risks of dehydration, which can induce heat-related illness. Proper rehydration with appropriate amounts of water and electrolytes is essential to aid body fluid homeostasis. Wearable sweat sensors which can monitor both the sweat rate and sweat electrolyte concentration may be an effective tool for determining appropriate rehydration. Here, we developed a novel potentially wearable sensor that can monitor both the local sweat rate and sweat electrolyte concentration continuously. The new device includes a system with a short microfluidic pathway that guides the sweat appearing on the skin to a small space in the device to form a quantifiable droplet. The sweat rate is assessed from the time for the droplet to appear and droplet volume, while an integrated electric sensor detects the sodium chloride concentration in each sweat droplet. We demonstrated that this new device could record both the flow rates of artificial sweat and its sodium chloride concentration in ranges of human sweating with an accuracy within ±10%. This is equivalent to the accuracy of commercially available sweat rate meters and sweat ion sensors. The present study provides a new perspective for the design of wearable sensors that can continuously monitor sweat rates and sweat electrolyte concentrations for potential application to a healthcare device.
全球变暖导致的气温升高增加了脱水风险，而脱水会引发与热相关的疾病。用适量的水和电解质进行适当补液对于维持体液平衡至关重要。能够监测出汗速率和汗液电解质浓度的可穿戴汗液传感器可能是确定适当补液的有效工具。在此，我们开发了一种新型的潜在可穿戴传感器，它可以连续监测局部出汗速率和汗液电解质浓度。新设备包括一个具有短微流体通道的系统，该通道将出现在皮肤上的汗液引导至设备中的一个小空间，以形成可量化的液滴。出汗速率通过液滴出现的时间和液滴体积来评估，而集成电传感器则检测每个汗液液滴中的氯化钠浓度。我们证明，这种新设备能够在人体出汗范围内记录人工汗液的流速及其氯化钠浓度，准确率在±10%以内。这与市售出汗速率计和汗液离子传感器的准确率相当。本研究为可穿戴传感器的设计提供了新视角，这种传感器能够连续监测出汗速率和汗液电解质浓度，有望应用于医疗保健设备。
