Hydrophobic interaction chromatography of homo-oligonucleotides on derivatized sepharose CL-6B. Using and relating two different models for describing the effect of salt and temperature on retention.

The effect of salt and temperature on the interaction of homo-oligonucleotides with a derivatized Sepharose CL-6B hydrophobic support has been explained by the application of two different models: the solvophobic theory and the preferential interaction analysis. It has been shown that the two approaches give adequate descriptions of the experimental results. The models were used in order to estimate, respectively the parameter C, which is proportional to the reduction in hydrophobic exposed surface area upon adsorption, and the number of water and salt ions released upon adsorption. It was concluded that the magnitude of these parameters can be strongly influenced by the temperature, the hydrophobicity of the bases of the nucleotides, the molecular mass of the oligonucleotides and the presence of secondary structures. Parameter C was quantitatively related with the number of water molecules and salt ions released upon adsorption. These parameters were found to correlate linearly in cases where structural changes with temperature are not significant.