Design and application of ion concentration polarization for preconcentrating charged analytes

Micro/nanofluidic devices integrated with ion concentration polarization (ICP) phenomenon have been used to preconcentrate low-abundant molecules for separation and detection purposes. This work reviews ICP-based devices focused on electrokinetic fundamentals of ICP in microfluidics and related design factors. We discuss various designs of ICP devices and then provide insight on the role of design factors in ICP function. In addition, fabrication methods and relevant materials for making ICP devices and nanojunctions are explained. This work provides the most up-to-date applications of ICP with emphasis on active and passive methods in controlling and stabilizing streams of preconcentrated molecules to enhance the separation and detection efficiency in diagnostics, desalination, and electrodialysis.