title: Enhanced solubilisation of six PAHs by three synthetic cyclodextrins for remediation applications: molecular modelling of the inclusion complexes.
abstract: Solubilisation of six polycyclic aromatic hydrocarbons (PAHs) (acenaphthene, anthracene, fluoranthene, fluorene, phenanthrene and pyrene) by three synthetic cyclodextrins (CDs) (2-hydroxypropyl-β-CD, hydroxypropyl-γ-CD and randomly methylated-β-CD) was investigated in order to select the CD which presents the greatest increase in solubility and better complexation parameters for its use in contaminated scenarios. The presence of the three cyclodextrins greatly enhanced the apparent water solubility of all the PAHs through the formation of inclusion complexes of 1:1 stoichiometry. Anthracene, fluoranthene, fluorene and phenanthrene clearly presented a higher solubility when β-CD derivatives were used, and especially the complexes with the randomly methylated-β-CD were favoured. On the contrary, pyrene presented its best solubility results when using 2-hydroxypropyl-γ-CD, but for acenaphthene the use of any of the three CDs gave the same results. Complementary to experimental phase-solubility studies, a more in-depth estimation of the inclusion process for the different complexes was carried out using molecular modelling in order to find a correlation between the degree of solubilisation and the fit of PAH molecules within the cavity of the different CDs and to know the predominant driving forces of the complexation.
authors.affiliation: Institute of Natural Resources and Agrobiology of Seville, Agrochemistry and Soil Conservaton Department, Science Research Council, IRNAS-CSIC, Seville, Spain. morillo@irnase.csic.es
authors.forename: Esmeralda
authors.initials: E
authors.lastname: Morillo
authors.forename: María Antonia
authors.initials: MA
authors.lastname: Sánchez-Trujillo
authors.forename: José Ramón
authors.initials: JR
authors.lastname: Moyano
authors.forename: Jaime
authors.initials: J
authors.lastname: Villaverde
authors.forename: María Eulalia
authors.initials: ME
authors.lastname: Gómez-Pantoja
authors.forename: José Ignacio
authors.initials: JI
authors.lastname: Pérez-Martínez
mesh_terms: D003505:Cyclodextrins / Q000737:chemistry*; D008958:Models, Molecular; D062105:Molecular Docking Simulation; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*; D012995:Solubility
chemical_list: D003505:Cyclodextrins; D011084:Polycyclic Aromatic Hydrocarbons