With an approach towards generating a wearable skin hydration detecting system, simple, cheap, and flexible skin hydration sensing strategy was demonstrated here using an interdigitated electrode (IDE) coated with polydimethylsiloxane (PDMS) matrix. Aluminium IDE with a 400 µm gap and 250 µm electrode sizes were fabricated using a photolithography method. Morphological characterizations were performed using a high power microscope, 3D-profilometer, and scanning electron microscope. The dimensions of electrodes and gaps measured through electron microscopic analysis affirmed the exactness of IDE and the fabrication process. After coated with PDMS polymer, the IDE/PDMS surface was examined under a high power microscope and 3D-profilometer. The optical characterization revealed the polymer was coated on IDE through the color-shade changes and smooth surface observed under an optical microscope and the respective 3D-visualization. IDE/PDMS was also analyzed by an atomic force microscope, revealing the smoothness of the IDE surface. Electrical characterizations were performed using different pH and urea solutions and the sweat to investigate the influence of real-time and artificial sweat on IDE/PDMS. As the device showed appropriate results with real-time sweat and no effect with artificial interferences, it is highly encouraged and recommended for detecting skin hydration and the related illnesses with the point-of-care concept.

中文翻译：

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导电交叉电极上的弹性聚二甲基硅氧烷聚合物用于分析皮肤水合动力学

通过一种生成可穿戴皮肤水合检测系统的方法，这里使用涂有聚二甲基硅氧烷 (PDMS) 基质的叉指电极 (IDE) 展示了简单、廉价且灵活的皮肤水合传感策略。使用光刻方法制造具有 400 µm 间隙和 250 µm 电极尺寸的铝 IDE。使用高倍显微镜、3D 轮廓仪和扫描电子显微镜进行形态学表征。通过电子显微镜分析测量的电极和间隙尺寸证实了 IDE 和制造工艺的准确性。涂上 PDMS 聚合物后，IDE/PDMS 表面在高倍显微镜和 3D 轮廓仪下进行检查。光学表征表明，通过在光学显微镜下观察到的颜色深浅变化和光滑表面以及相应的 3D 可视化，聚合物被涂覆在 IDE 上。IDE/PDMS 还通过原子力显微镜进行分析，揭示了 IDE 表面的光滑度。使用不同的 pH 值和尿素溶液以及汗液进行电学表征，以研究实时汗液和人工汗液对 IDE/PDMS 的影响。由于该设备在实时出汗时显示出适当的结果，并且不受人工干扰的影响，因此强烈鼓励和推荐使用即时护理概念检测皮肤水分和相关疾病。显示 IDE 表面的平滑度。使用不同的 pH 值和尿素溶液以及汗液进行电学表征，以研究实时汗液和人工汗液对 IDE/PDMS 的影响。由于该设备在实时出汗时显示出适当的结果，并且不受人工干扰的影响，因此强烈鼓励和推荐使用即时护理概念检测皮肤水分和相关疾病。显示 IDE 表面的平滑度。使用不同的 pH 值和尿素溶液以及汗液进行电学表征，以研究实时汗液和人工汗液对 IDE/PDMS 的影响。由于该设备在实时出汗时显示出适当的结果，并且不受人工干扰的影响，因此强烈鼓励和推荐使用即时护理概念检测皮肤水合作用和相关疾病。