Supercoiled circular DNA retention in nonequilibrium chromatography: viscosity and velocity dependence--behavior difference with proteins.

This study demonstrates that the retention behavior of various circular double-stranded DNA molecules (3, 5, and 10 kb) increases over the entire flow-rate range (0.02-1.8 mL/min) at all the mobile phase viscosities (h). The transition between the two well-known nonequilibrium chromatography methods (slalom and hydrodynamic chromatography) is clearly visualized for proteins and does not appear for plasmids because of their strong compact structure. Also, the optimal conditions for F and h are determined to obtain the most efficient separation of these three plasmids in a minimum analysis time.