title: Polycyclic aromatic hydrocarbons as test probes to investigate the retention behavior of 1,3-alternate calix[4]arene silica-bonded stationary phases.
abstract: A series of polycyclic aromatic hydrocarbons (PAHs) of different size and shape has been used to characterize the chromatographic behavior of five calix[4]arene stationary phases in 1,3-alternate conformation synthesized in our laboratory. The selection of linear, four-ring nonlinear, and five-ring PAHs gave data on selectivity changes across range of the calix[4]arene columns. Retention of the 12 aromatic solutes has been evaluated at various methanol contents in the mobile phase (70-100% v/v) and column temperatures (20-45°C). The thermodynamic parameters underlying the retention mechanisms revealed that each of the five calix[4]arene columns exhibited variation in selectivity and retention of PAHs caused by enthalpy and entropy effects. The calixarene stationary phases substituted with electron-withdrawing groups exhibit enhanced selectivity toward PAHs in comparison to the rest of the investigated columns. The observed divergences are due to differences in solute-stationary phase interactions and originate in π-π and π-electron transfer specific to the analytes and the type of calix[4]arene functionalization at the upper rim, as well as steric and sorption phenomena.
authors.affiliation: Department of Organic Chemistry, Gdansk University of Technology, Gdańsk, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Sliwka-Kaszyńska
authors.forename: Marek
authors.initials: M
authors.lastname: Slebioda
mesh_terms: D047250:Calixarenes / Q000737:chemistry; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D010636:Phenols / Q000737:chemistry; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry / Q000302:isolation & purification*; D012822:Silicon Dioxide / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D010636:Phenols; D011084:Polycyclic Aromatic Hydrocarbons; C121325:calix(4)arene; D047250:Calixarenes; D012822:Silicon Dioxide
keywords: Calix[4]arene stationary phases; Column characterization; Polycyclic aromatic hydrocarbons; Retention behavior; Thermodynamics