Design of an electronic interface for capacitively coupled four-electrode conductivity detection in capillary electrophoresis microchip
| Autor: | J. Bastemeijer, F. Laugere, Michiel J. Vellekoop, G.W. Lubking |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Chemistry
business.industry Detector Metals and Alloys Analytical chemistry Differential amplifier Input impedance Conductivity Condensed Matter Physics Surfaces Coatings and Films Electronic Optical and Magnetic Materials Capillary electrophoresis Common-mode rejection ratio Electrode Materials Chemistry Optoelectronics Electrical and Electronic Engineering business Instrumentation Electrical impedance |
| Zdroj: | Sensors and Actuators B: Chemical. 83:104-108 |
| ISSN: | 0925-4005 |
| DOI: | 10.1016/s0925-4005(01)01051-6 |
| Popis: | In this paper, we present an electronic interface dedicated to capacitively coupled four-electrode liquid conductivity detection in micro capillary electrophoresis devices. Due to the small dimensions of the detector ( 106 μm ×170 μm), it is necessary to adapt the read-out interface. Our study focuses on two major aspects of the four-electrode setup: First, the current which flows between the two outer electrodes must be known. Second, the two inner electrodes must be connected to a high input impedance and high common mode rejection ratio (CMRR) differential amplifier. The results obtained in a miniaturized CE channel show a linear response with liquid impedances within a range of 250 kΩ to 3.45 MΩ (for a MES/His buffer, this compares to a concentration range of 0.2–20 mM). |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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