In this study, the chip gel electrophoresis with LIF detection was applied in protein profiling of fractionated and total extracts of maize standards. The sensitivity of such determinations can be enhanced by lyophilization of extracts or employing filtering and preconcentration with cutoff filters. Combinatorial peptide ligand library applied for sample processing prior to the electrophoretic analysis was, especially, an effective pretreatment step in the determination of low-abundance proteins. Several repeatable differences were observed for protein profiles between maize standards not containing the genetically modified organisms (GMOs) and those containing GMO, which can be potentially employed for identification of GMO in maize samples and foods of maize origin.