Mobile-phase-viscosity dependence on DNA separation in slalom chromatography

Slalom chromatography (SC) is an alternative chromatographic procedure for the separation of relatively large double-stranded DNA molecules and is bas ed on a new principle. The retardation of the DNA fragments from the cleava ge of the Lambda DNA by the KpnI restriction enzyme was studied using an ac etonitrile-phosphate buffer as a mobile phase with various concentrations o f viscosity modifier (i.e. glycerol) and a C-1 column as a stationary phase . The DNA molecule retention was accurately described over the glycerol con centration range using a model previously established. It was shown that th e eluent viscosity increase enhanced the slalom chromatographic capacity to separate the DNA fragments. A connection between SC and 'hydrodynamic chro matography' processes was predicted to link the two processes in a global s eparation mechanism based on a non-equilibrium principle. (C) 2000 Elsevier Science B.V. All rights reserved.