Origami paper-based sample preconcentration using sequentially driven ion concentration polarization

Ion concentration polarization (ICP) is one of the preconcentration techniques which can acquire a high preconcentration factor. Still, the main hurdles of ICP are its instability and low efficiency under physiological conditions with high ionic strength and abundant biomolecules. Here, we suggested a sequentially driven ICP process, which enhanced the electrokinetic force required for preconcentration, enabling enrichment of highly ionic raw samples without increasing the electric field. We acquired a 13-fold preconcentration factor (PF) in human serum using a paper-based origami structure consisting of multiple layers for three-dimensional sequential ICP (3D seq-ICP). Moreover, we demonstrated a paper-based enzyme-linked immunosorbent assay (ELISA) by 3D seq-ICP using tau protein, showing a 6-fold increase in ELISA signals.

Automated summary

Ion concentration polarization (ICP) is a preconcentration technique with the potential for high preconcentration factor, but faces challenges of instability and low efficiency under physiological conditions. A sequentially driven ICP process has been proposed to enhance the preconcentration of highly ionic raw samples without increasing the electric field, resulting in significant preconcentration factor and signal enhancement in enzyme-linked immunosorbent assay (ELISA) using tau protein.