Research Center for Applied Sciences, Academia Sinica, Taipei, 11529, Taiwan.
Lab Chip. 2011 May 21;11(10):1740-6. doi: 10.1039/c0lc00620c. Epub 2011 Mar 30.
This paper reports a novel pressure sensor with an electrical readout based on electrofluidic circuits constructed by ionic liquid (IL)-filled microfluidic channels. The developed pressure sensor can be seamlessly fabricated into polydimethylsiloxane (PDMS) microfluidic systems using the well-developed multilayer soft lithography (MSL) technique without additional assembly or sophisticated cleanroom microfabrication processes. Therefore, the device can be easily scaled up and is fully disposable. The pressure sensing is achieved by measuring the pressure-induced electrical resistance variation of the constructed electrofluidic resistor. In addition, an electrofluidic Wheatstone bridge circuit is designed for accurate and stable resistance measurements. The pressure sensor is characterized using pressurized nitrogen gas and various liquids which flow into the microfluidic channels. The experimental results demonstrate the great long-term stability (more than a week), temperature stability (up to 100 °C), and linear characteristics of the developed pressure sensing scheme. Consequently, the integrated microfluidic pressure sensor developed in this paper is promising for better monitoring and for characterizing the flow conditions and liquid properties inside the PDMS microfluidic systems in an easier manner for various lab on a chip applications.
本文报道了一种基于填充有离子液体（IL）的微流道的电液电路构建的具有电读出功能的新型压力传感器。所开发的压力传感器可以使用成熟的多层软光刻（MSL）技术无缝地制造到聚二甲基硅氧烷（PDMS）微流控系统中，而无需额外的组装或复杂的洁净室微制造工艺。因此，该设备易于扩展并且是完全一次性的。压力感应是通过测量构建的电液电阻器的压力感应电阻变化来实现的。此外，设计了电液惠斯通电桥电路以进行精确和稳定的电阻测量。使用加压氮气和各种流入微流道的液体对压力传感器进行了特性测试。实验结果表明，所开发的压力传感方案具有出色的长期稳定性（超过一周）、温度稳定性（高达 100°C）和线性特性。因此，本文中开发的集成微流控压力传感器有望更好地监测和表征 PDMS 微流控系统内部的流动条件和液体特性，从而更轻松地应用于各种片上实验室应用。
