Directed Patterned Adsorption of Magnetic Beads on Polyelectrolyte Multilayers on Glass

Here we present a study of patterning micrometer-sized features on glass surfaces with magnetic colloids. We employ a polyelectrolyte foundation composed of five bilayers on the surface of a glass slide. The directed assembly of carboxylate-modified superparamagnetic particles is accomplished by creating patterned regions of opposite charge via polymer-on-polymer stamping. Dot patterns created in a two-dimensional square array produce colloidal clusters with diameters ranging from 1 to 12 μm. Individual magnetic particles were patterned on the glass surface with micrometer-scale precision. Striped patterns also produced lines of magnetic particles varying in spacing and width from 1 to 7 μm.