Hand-held Automated Instrument for Microchip Electrophoresis with Amperometric Detection
Poster Mar 17, 2015
D.F. Pozo-Ayuso, A. Fernández-la-Villa, M. Castaño-Álvarez
Microchips electrophoresis (ME) in combination with electrochemical detection (ED) can bring a new generation of point-of-care (POC) analysis systems in which would be integrated the main steps of an analytical process. However, the use of these miniaturized devices also requires the development of a new instrumentation in concordance with the features of ME-ED, specially, relative to miniaturization and portability.
Thus, a second-generation of a battery-powered portable electrophoresis instrument (iHVStat) for using microchips electrophoresis with electrochemical detection has been developed. As the first-generation , the main unit of the instrument (150x165x95mm) consists of four-outputs high voltage power supply (HVPS) and a bipotentiostat with 2-channels for dual electrochemical detection (Figure 1). The use of an electrochemical transduction system simplifies the instrument developments, since non-optical elements are required.
Furthermore, a new reusable microfluidic platform has been also designed for using the microchips with the portable instrument. The platform with the ME-ED is directly inserted in the main unit of the instrument making easier the use of the complete system. It is controlled with a user-friendly PC software developed for microchip electrophoresis.
The performance of the electrophoresis platform has been evaluated using single- and dual-channel SU-8/Pyrex microchips with different models of integrated electrodes including microelectrode and interdigitated arrays. The successful performance of the complete system has been demonstrated in different analytical applications such as separation of neurotranmitters, chloro-phenols, purine-derivatives, vitamins, polyphenolic acids and flavones.
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