New calixarene-bonded stationary phases in high-performance liquid chromatography: comparative studies on the retention behavior and on influences ofthe eluent

The chromatographic behavior of six calixarene-bonded stationary phases is reported. Varying analyte selectivities (i.e., for phenols, substituted aro matics, polycyclic aromatic hydrocarbons, barbituric acid derivatives, xant hines) exist as a function of the ring-size of the calix[n]arenes (n=4, 6, 8) and the substitution at the "upper rim" with para-tert.-butyl groups. Al though eluents with unusually high proportions of water were used, a compar ison with conventional reversed-phase (RP) columns shows a predominantly re versed-phase character with remarkable selectivities of these phases. The i nfluences of several organic solvents on retention variations of solutes ar e compared for RP-C-18, phenyl and calixarene phases. (C) 2000 Elsevier Sci ence B.V. All rights reserved.