A thin cover glass chip for contactless conductivity detection in microchip capillary electrophoresis
- 作者：Zuanguang Chen ; Quanwen Li ; Oulian Li ; Xie Zhou ; You Lan ; Yuanfang Wei ; Jinyuan Mo
- 关键词：Micro-total analysis systems (μ ; -TAS) ; Microchip ; Contactless conductivity detection ; Capacitively coupled contactless conductivity detection ; High frequency conductivity detection
- 刊名：Talanta
- 出版年：2007
- 期刊代码：106_00399140
- 类别：ch
- 出版时间：30 March 2007
- 卷：71
- 期：5
- 页码：1944-1950
- 文件大小：274 K
摘要
A microfabricated thin glass chip for contactless conductivity detection in chip capillary electrophoresis is presented in this contribution. Injection and separation channels were photolithographed and chemically etched on the surface of substrate glass, which was bonded with a thin cover glass (100 μm) to construct a new microchip. The chip was placed over an independent contactless electrode plate. Owing to the thinness between channel and electrodes, comparatively low excitation voltage (20–110 V in Vp–p) and frequency (40–65 kHz) were suitable, and favorable signal could be obtained. This microchip capillary electrophoresis device was used in separation and detection of inorganic ions, amino acids and alkaloids in amoorcorn tree bark and golden thread in different buffer solutions. The detection limit of potassium ion was down to 10 μmol/L. The advantages of this microchip system exist in the relative independence between the microchip and the detection electrodes. It is convenient to the replacement of chip and other operations. Detection in different position of the channel would also be available.