The PSC/Ag/Au device yields a still greater increase in the rate of enrichment for three reasons. First, the PSC bead bed provides fluidic stabilization within the entire IDZ volume by geometric restriction of vortices and by the conduction of cations along the charged surface of the beads through the IDZ. Second, both the fluid velocity and the electric field are enhanced in the bead-occupied channel segment due to its increased fluidic and electrical resistance. Finally, dispersion is expected to be mitigated by the beads. These last two conclusions are supported by horizontally aligned normalized intensity profiles for all three device architectures (Figure ).