Controlling the electrokinetic transport of polyelectrolytes

Abstract

We investigated the electrokinetic transport mechanisms that drive active transport of charged species in a homogeneous electric field. Microscopy and streaming potential measurements were used to determine electroosmotic mobilities of glass capillaries. The electroosmotic flow was varied by applying poly(diallyldimethylammonium chloride) (pDADMAC) for various coating conditions. This revealed that the adsorption of pDADMAC in the presence of divalent counterions results in a conformational rearrangement of the adsorped pDADMAC.

Electrophoretic mobilities of fluorescein and poly(allylamine hydrochloride) were determined using microscopy for different background concentrations of NaCl. On the basis of a theoretical model, this data could be used to extrapolate absolute electrophoretic mobilities for these analytes.