Investigation of Ion Concentration Polarization in original Micro-Nanofluidic devices

Ion perm-selectivity is one of the major proprieties of nanofluidic devices. Within the influence of an electric field through an ion-selective nanochannel, a phenomenon called ICP “Ion Concentration Polarization” appears and creates near the micro-nanojunction an ion depletion/concentration zone at the anodic/cathodic side, respectively. Recent works have shown that the anodic depletion can be used as a powerfull preconcentration tool for detection of molecules (DNA, proteins…). Here, we present an original micro-nanofluidic device realized by standard silicon technology which exhibits circular micro-nanojuction. The ICP phenomenon was demonstrated on fluorescent molecules (fluorescein). The radial configuration of the nanochannels may bring different advantages compared to the classical “Bypass” device mostly reported in literature.