The invention provides compositions, methods and kits for high speed, high resolution of analytes by capillary electrophoresis starting with uncoated capillaries. The compositions comprise a sieving component, comprising a non-crosslinked acrylamide polymer, and a surface interaction component, comprising at least one uncharged and non-crosslinked water-soluble silica-adsorbing polymer. Methods for employing the novel compositions in capillary electrophoresis are provided. Kits comprising the novel compositions for use in the novel methods are also provided.