A polydimethylsiloxane electrophoresis microchip with a thickness controllable insulating layer for capacitatively coupled contactless conductivity detection

作者：Liu, Junshan^*; Xu, Fei; Wang, Sifeng; Chen, Zuanguang; Pan, Jianbin; Ma, Xinran; Jia, Xiaokai; Xu, Zheng; Liu, Chong; Wang, Liding

来源：Electrochemistry Communications, 2012, 25: 147-150.

DOI：10.1016/j.elecom.2012.10.012

• Capacitatively coupled contactless conductivity detection
• Electrophoresis
• Microchip
• Microfluidic
• PDMS

A polydimethylsiloxane (PDMS) electrophoresis microchip with a thickness-controllable insulating layer for capacitatively coupled contactless conductivity detection is presented. A PDMS film is spin-coated on a glass slide with Pt microelectrodes to be the insulating layer, and then permanently bonded with a PDMS channel plate to make the whole microchip. The thickness of PDMS films can be precisely controlled down to submicrometers. With a microchip with a 0.6 mu m-thick PDMS insulating layer, a superior limit of detection (LOD) of 0.07 mu M for Na+ was obtained. For comparison, another two microchips with the same design but different insulating layer thicknesses (15 mu m and 50 mu m) were tested, and LODs were 1 mu M and 3 mu M respectively, which are almost two orders of magnitude higher. Moreover, the microchip detector also exhibited excellent linearity, reproducibilities and separation efficiencies.

• 出版日期2012-11
• 单位大连理工大学; 中山大学