Development of a polymer-based easy-to-fabricate micro-free-flow electrophoresis device

Since 1990s, micro-free-flow electrophoresis (mu FFE) devices have been developed to allow for smaller sample volume and reagent consumption. To solve several technical problems involving the generation of electrolysis gas on the electrodes, most of the mu FFE devices reported in the past were fabricated using elaborate micromachining process on silicon or glass substrates. However, high-cost micromachining processes were required and these were not suitable for mass production. In this paper, we report a polymer-based easy-to-fabricate mu FFE device using a poly(methyl methacrylate-co-styrene), P(MMA-co-S), substrate and tetra-PEG gel for preventing the invasion of electrolysis gas into the separation chamber. In the separation experiment using a mixture of rhodamine B and sulforhodamine B, the resolution increased linearly with the increase of the applied voltages up to 50V, whereas a deviation from the linear relation was observed above 50V, which is possibly the Joule heating. These results indicate that this device could be applicable to separation of biological samples. (C) 2015 The Japan Society of Applied Physics