School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Lab Chip. 2017 Jun 27;17(13):2323-2329. doi: 10.1039/c7lc00390k.
Lightweight, flexible, stretchable, and wireless sensing platforms have gained significant attention for personal healthcare and environmental monitoring applications. This paper introduces an all-soft (flexible and stretchable), battery-free, and wireless chemical microsystem using gallium-based liquid metal (eutectic gallium-indium alloy, EGaIn) and poly(dimethylsiloxane) (PDMS), fabricated using an advanced liquid metal thin-line patterning technique based on soft lithography. Considering its flexible, stretchable, and lightweight characteristics, the proposed sensing platform is well suited for wearable sensing applications either on the skin or on clothing. Using the microfluidic sensing platform, detection of liquid-phase and gas-phase volatile organic compounds (VOC) is demonstrated using the same design, which gives an opportunity to have the sensor operate under different working conditions and environments. In the case of liquid-phase chemical sensing, the wireless sensing performance and microfluidic capacitance tunability for different dielectric liquids are evaluated using analytical, numerical, and experimental approaches. In the case of gas-phase chemical sensing, PDMS is used both as a substrate and a sensing material. The gas sensing performance is evaluated and compared to a silicon-based, solid-state gas sensor with a PDMS sensing film.
轻量、灵活、可拉伸和无线感测平台因其在个人医疗保健和环境监测应用中的重要性而受到广泛关注。本文介绍了一种全软（灵活和可拉伸）、无电池和无线化学微系统，该系统使用基于软光刻的先进液态金属细线图案化技术，由镓基液态金属（共晶镓-铟合金，EGaIn）和聚二甲基硅氧烷（PDMS）制成。考虑到其灵活、可拉伸和轻量的特点，所提出的感测平台非常适合可穿戴感测应用，无论是在皮肤上还是在衣服上。使用微流控感测平台，通过相同的设计演示了液相和气相挥发性有机化合物（VOC）的检测，这为传感器在不同工作条件和环境下运行提供了机会。在液相化学感测的情况下，使用分析、数值和实验方法评估了不同介电液体的无线感测性能和微流体电容可调性。在气相化学感测的情况下，PDMS 既用作基底又用作感测材料。评估并比较了 PDMS 感测膜的硅基固态气体传感器的气体感测性能。
