title: Selectivity of calixarene-bonded silica-phases in HPLC: description of special characteristics with a multiple term linear equation at two different pH-values.
abstract: Six different calixarene-bonded phases were characterized by analyzing 36 and 26 solutes at pH 3 and 7, respectively. Dolan and Snyder's multiple term linear equation was used to correlate retention factors k' to parameters of the solutes and columns. The column parameters have been related to molecular properties of the stationary phases and new suggestions were made for the interpretation of steric selectivity. Ionic and polar interactions have been found dependent on pH value, while steric interactions are less dependent and hydrophobic interactions remain unchanged. Distinct differences of the supported interactions were confirmed between the calixarene-bonded and the common alkyl-bonded silicas. By use of the parameters, values of k' can be estimated with an average deviation of 2.50 and 7.92% at low and neutral pH-value, respectively.
authors.affiliation: Institute of Pharmacy, Pharmaceutical/Medicinal Chemistry, Ernst-Moritz-Arndt-University Greifswald, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Schneider
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Meyer
authors.forename: Thomas
authors.initials: T
authors.lastname: Jira
mesh_terms: D047250:Calixarenes / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D016014:Linear Models; D008956:Models, Chemical; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D047250:Calixarenes; D012822:Silicon Dioxide