Butyl acrylate (BA)- and lauryl acrylate (LA)-based monolithic stationary phases for CEC were synthesized, using a redox system as initiator of polymerization. BA monoliths were initiated with ammonium peroxodisulfate, whereas LA columns were obtained with lauroyl peroxide as initiator. In both cases, TEMED was used to activate the process. The influence of porogenic solvent composition on both morphological and electrochromatographic properties of the resulting monoliths was investigated. Excellent efficiencies (minimum plate heights of 4.2-6.3 mu m for BA columns and 2.6-5.3 mu m for LA stationary phases, for a PAHs mixture) were achieved. The capability of separation of both types of monolithic beds was compared by the analysis of complex mixtures of polycyclic aromatic hydrocarbons and anabolic steroids.