Locational enrichment of low-abundance analytes through force-environment-modulation microsystem with ion concentration polarization

Ion concentration polarization (ICP) effect in micro-nanofluidic devices can concentrate low-concentration molecules. In this paper, we proposed a novel ICP-based enrichment system with horizontal barriers that adjust the force environment of charged particles, to achieve specific locational analytes enrichment. Mechanism of analyte enrichment through force modulation is revealed through numerical simulation using microchannels with varied channels widths, which is further validated through physical experiment. Overall, a specific targetoriented structure and load regulation method was proposed, under which the low-abundance analytes could be locationally concentrated by similar to 4000 times. This study is expected to develop an innovative method for specifically locational ion enrichment in terms of scientific principles, providing theoretical and technical support for concentration and detection of charged substances in both research and industry such as biology, environment, chemistry studies, etc.