Solvatochromic characterization of silica-based stationary phases for liquid chromatography

UV-visible reflectance spectra of solvatochromic dyes and mobile phases wit h compositions in the ranges from 100 to 5 % (nu/nu) acetonitrile and metha nol in water have been used to characterize octadecyl-, octyl-, phenyl-, cy ano-, amino-, and diol-bonded silica stationary phases. Dipolarity/polariza bility (pi*), hydrogen-bond (HB) donor acidity (alpha), and HE acceptor bas icity (beta) of the stationary phases were determined in the mobile phases. Interaction properties of the stationary phases are affected both by the t ypes of bonded moiety and by the composition of the mobile phase.