DNA migration regimes in hydrodynamic chromatography and slalom chromatography: evidence for a transition

Recently, we hypothesized that DNA separation mechanisms in slalom chromatography (SC) and packed column hydrodynamic chromatography (HDC) could be connected and simultaneously observed ‘J. Chromatogr. A 886 (2000) 1’. The present paper describes the migration of various circular and linear double-stranded DNAs in a chromatographic system using a C1 stationary phase and an acetonitrile–phosphate buffer mixture as a mobile phase. The migration dependence on the flow rate for the different species showed the relative contribution of both the SC and HDC separation mechanisms. A transition between the SC and HDC regimes was demonstrated for the first time. In addition, the data were analyzed in terms of polymer migration in a dense structure. Three different behaviors were distinguished in relation to the size and the compactness of the nucleic acid.