Low-Voltage Origami-Paper-Based Electrophoretic Device for Rapid Protein Separation

We present an origami paper-based electrophoretic device (oPAD-Ep) that achieves rapid (similar to 5 min) separation of fluorescent molecules and proteins. Due to the innovative design, the required driving voltage is just similar to 10 V, which is more than 10 times lower than that used for conventional electrophoresis. The oPAD-Ep uses multiple, thin (180 mu m/layer) folded paper layers as the supporting medium for electrophoresis. This approach significantly shortens the distance between the anode and cathode, and this, in turn, accounts for the high electric field (>1 kV/m) that can be achieved even with a low applied voltage. The multilayer design of the oPAD-Ep enables convenient sample introduction by use of a slip layer as well as easy product analysis and reclamation after electrophoresis by unfolding the origami paper and cutting out desired layers. We demonstrate the use of oPAD-Ep for simple separation of proteins in bovine serum, which illustrates its potential applications for point-of-care diagnostic testing.