Both ICP and fICP accomplish localized depletion of the ions of the background electrolyte (BGE). A key feature of the ion depleted zone (IDZ) is its low ionic conductivity, which leads to a strong local enhancement of the electric field and formation of an extended electric field gradient, along which charged species can be focused based on their migration against opposing convection (Scheme 1b). Depletion of BGE ions can proceed via faradaic (charge transfer) reactions that occur at an electrode -a process called faradaic ICP (fICP) (Scheme 1a). fICP is analogous to ICP driven by selective charge transport at a permselective membrane with the exception that the local concentration of the BGE is modulated by charge transfer reactions. fICP has been demonstrated as an alternative to conventional ICP for separation of particles, modulation of dielectrophoretic force, and enrichment of charged species for analysis, where the latter has been carried out in paper-based analytical devices. In these applications, electrochemical reactions are most commonly facilitated by a bipolar electrode (BPE). Scheme 1a depicts a well-characterized route to fICP that proceeds via base neutralization of buffer ions comprising the BGE in a microfluidic channel with an embedded planar electrode. Here, at the planar electrode, water is reduced to generate OH -, which goes on to generate uncharged species (tris(hydroxymethyl)aminomethane, (Tris)) by accepting a proton from the BGE cation (TrisH + ).