Column efficiency and separation of DNA fragments using slalom chromatography: Hydrodynamic study and fractal considerations

Novel equations (Guillaume Y. C.; et al. Anal. Chem, 2000, 72, 853) were de veloped to describe the large double-stranded DNA molecule retention in sla lom chromatography (SC). These equations were applied for the first time to model both the "apparent selecticity" and the resolution between tao elute d DNA fragments on a chromatogram, a study of the column efficiency corrobo rated the fact that slalom chromatography is not based on an adsorption or equilibrium phenomenon, but can be attributed to a hydrodynamic phenomenon. Using a combination of the dynamics of DNA fragment progression in the col umn and fractal considerations, it was shown that the apparent selectivity depends both on the DNA fragment sizes and mobile-phase flow rate and there fore a balance between two hydrodynamic regimes. A chromatographic response function was also used to obtain the most efficient separation conditions for a mixture of DNA fragments in a minimum analysis time. The chromatograp hic data confirmed that in SC the now rate can increase or maintain the sep aration efficiency with an associated decrease in the analysis time. This c onstitutes an attractive outcome in relation to the classical chromatograph ic separation.