Abstract: Methods and apparatus for the separation of polysaccharides, particular heparin products, and glycosylated molecules are provided. The separation is based on the molecular weight and charge, by application of an electric field across a low-friction matrix, modified with a charged separation agent comprising charged regions ordered in a monotonous sequence distributed throughout the matrix, to generate a charge density gradient formed when an external electric field is applied. Saccharides of different charges migrate differently across the porous matrix and immobilized by charge neutralization in different charge regions of the matrix.