ORGN 174 |
| Fluoroionophores chemically communicate ion concentrations and have been the subject of substantial investigation in metal ion analysis. New rhodamine derivatices as well as new fluorescein derivatives were synthesized and studied their binding properties towards metal ions in aqueous solution. Rhodamine B derivatives have also been used as fluorescent chemosensors for metal ions, in which the spirolactam (nonfluorescent) to ring opened amide (fluorescent) process was utilized. Especially, two structurally similar fluorescein derivatives showed an extremely high selectivity towards Ag+ ion through a relatively different binding mechanism than the previously reported fluorescein derivatives. Furthermore, upon the addition of Ag+ ions, these two chemosensors showed completely different fluorescent changes through different binding modes. The different binding mechanisms of these two compounds with Ag+ were explained based on the colorimetric changes as well as the ESI mass data. It is believed that this result can provide a new strategy for the development of fluorescent chemosensors based on fluorescein derivatives. |
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Total Synthesis, Materials, Devices and Switches, Molecular Recognition and Self-Assembly, Biologically-Related Molecules and Processes
8:00 PM-10:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Organic Chemistry |