Solvation processes on phenyl-bonded stationary phases-The influence of polar functional groups.

A series of phenyl-bonded stationary phases with incorporated polar functional groups was subjected to an adsorption investigation. Measurement of acetonitrile and methanol adsorption was obtained using the minor disturbance method. It was observed that adsorption of organic solvent strongly depends on the presence of polar functional groups in the bonded phases that influence the hydrophobicity and polarity of the stationary phase surface. Additionally, relative adsorption of acetonitrile and methanol confirms earlier observations, that the presence of amine and amide groups in the stationary phase changes the relative elution strength of organic solvents. The heterogeneous surface of the stationary phase makes it possible to observe the competitiveness of the water and organic solvent adsorption.