LEE- Kimya Lisansüstü Programı

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http://hdl.handle.net/11527/19351

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Yazar "Amharar, Sana" ile LEE- Kimya Lisansüstü Programı'a göz atma
  • Öge
    Stimuli responsive supramolecular polymers and ida sensors based on host-guest interaction and ion pair recognition ability of calix[4]pyrroles
    (Lisansüstü Eğitim Enstitüsü, 2021) Amharar, Sana ; Aydoğan, Abdullah ; 710239 ; Kimya
    Calix[4]pyrroles are the macrocyclic compounds with four pyrrole units connected to each other via sp3 carbon atoms. Their anion binding ability in organic solvent has make them gain attention in the sensing area. It is cost-effective, easy to synthesize and to modify. This thesis is divided into four parts, first chapter corresponding to an introduction about generality in supramolecular chemistry and calix[4]pyrroles, and the next three different chaptersare based on the three articles published during this PhD study. In Chapter 2, supramolecular polymerization of calix[4]pyrroles bearing tethered carboxylate functional groups was reported in the form of their tetrabutylammonium salts. At high concentrations one of the calix[4]pyrroles with a shorter linker between the calixpyrrole core and the carboxylate unit was found to give a thermoresponsive supramolecular polymer gel. In Chapter 3, rationally designed ion pairs were integrated into a calix[4]pyrrole skeleton, resulting the formation of an ion pair recognition based linear supramolecular polymer. The effect of simultaneous host-guest and cation- interactions between carboxylate functional calix[4]pyrrole and cetyltrimethylammonium cation was investigated by NMR, viscosity, SEM, and DSC analyses. The resulting supramolecular polymer was found to show temperature induced rapid and reversible sol-gel transition through van der Waals interactions of cetyl units. And finally in chapter 4, cost-effective fluorescence turn-on indicator-displacement-assay (IDA) sensors based on octamethylcalix[4]pyrrole receptor and tetrabutylammonium salts of 4-methylumbelliferone and fluorescein indicators were developed for highly sensitive detection of fluoride anion. The IDA sensor assembly relies on the hydrogen bonding between calix[4]pyrrole and carboxylate units of indicators and further displacement of receptors with target analyte. While all the sensors displayed rapid and selective sensitivity towards fluoride over the other anions, 4-methylumbelliferone based IDA system was also found to have a visual color change for the sensing of fluoride anion. The experimental results revealed that fluorescein-based IDA sensor could be used for the sensing of fluoride anion with a detection limit as low as 3.2 nM.