CHED 1122 |
| Veterinary antibiotics and pesticides containing cationic amines are often detected in natural waters. The fate and bioaccessibility of these compounds are influenced by their retention onto mineral surfaces. This study examines the influence of molecular structure, specifically delocalization, inductive effects, and proximity effects, on the nature and extent of amine sorption to soil minerals. Sorption of oxytetracycline onto metal oxide exceeded that of ciprofloxacin, but the reverse was true of sorption to aluminosilicates. Sorption studies of methylated anilines suggested that the presence of methyl groups on the nitrogen did not cause a steric hindrance to oxytetracycline sorption. Instead, repulsion between an ortho-substituted anionic moiety and the negatively charged mineral surface likely decreased the extent of oxytetracycline sorption. Further insight into structural criteria influencing sorption was obtained by varying the extent of delocalization of charge and the identity of electron donating/withdrawing substituents on a series of structurally related heterocyclic amines. |
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Undergraduate Research Poster Session: Environmental Chemistry
2:00 PM-4:00 PM, Monday, March 26, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Chemical Education |