Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Setup of micro free-flow electrophoresis, our state of development: Peripherie setup and chip-modification

: Müller, Dominik; Geiger, Sebastian; Rabenecker, Peter

Volltext (PDF; )

CE-Forum 2019. Online resource : December 11-12, 2019, Waldbronn
Online im WWW, 2019
Paper 52, 1 S.
CE-Forum <2019, Waldbronn>
Konferenzbeitrag, Elektronische Publikation
Fraunhofer ICT ()
free-flow electrophoresis

The background electrolyte passes from below (A - E) to the top (1 - 5). In the middle is the electrophoretic separation space, which is confined laterally by the plus and minus poles. After the separation space, the background electrolyte is temporarily subdivided into 25 fractions via a "comb". Thereafter, the individual fractions are combined again in 5 outputs. At the beginning of the separation chamber, the sample is injected into the separation chamber. Figure 4 shows schematically an electrophoretic separation of a sample solution with a negatively charged and neutrally charged analyte. The negative migrates towards the positive pole direction, while the neutral undergoes no migration due to lack of charge and is transported with the background electrolyte through the separation space. Initial experience with the chip, however, showed that there are three major disadvantages: 1. When applying a separation voltage (> 100 V), microbubbles (oxygen and hydrogen) develop at the electrodes, which inevitably arise due to the accompanying electrolysis reaction. If the microbubbles cannot be drained cleanly, the microfluidic flow profile and the electrophoresis are permanently disturbed. 2. It has already been described that the background electrolyte is divided into 25 fractions, but subsequently recombined. In the end, there are 5 outputs left, leading to a loss of separation resolution. 3. The commercial chip is constructed so that the structure is on the chip substrate. Finally, a film is "bonded" to complete the chip. However, it is believed that the moving foil leads to asymmetricalflow profiles. The goal is to construct a robust but also easy-to-handle setup. As a consequence, it is planned to modify the chip so that it can be used for future applications, e.g. electrochemical analysis of the outcoming fractions. The poster will represent the state of development with schematic flow diagrams and pictures of the current experimental setup.