Synthesis and design of fluorescence ligands to act as sensor for zinc
- UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
- Wei Gan (Creator)
- Institution
- The University of North Carolina Wilmington (UNCW )
- Web Site: http://library.uncw.edu/
- Advisor
- Robert Hancock
Abstract: Design and synthesis of ligands to detect low concentrations of Zn2+ in various systems are
being explored worldwide. The purpose of this research is to synthesize and study fluorescent
sensors for Zn2+ in nervous system by utilizing CHEF (Chelation Enhanced Fluorescence) effect.
TQA, a known compound, was synthesized and characterized. It is small and hydrophobic,
which may allow it to cross the blood-brain barrier. The quinolyl groups provide good
fluorescent properties. Ni2+, Cu2+, Cd2+, Pb2+ were selected to compare the selectivity of the
designed ligand for Zn2+. It was shown that TQA does have CHEF effect with Zn 2+ and Cd2+ (of
which Zn2+-ligand complex is 10 times stronger in terms of fluorescence intensity) and has no
CHEF effect with Ni2+, Cu2+, Pb2+. The drawback of TQA is that its solubility in water is too low
(only 10-5 M in 50% methanol/water) to test its pKa and formation constants with metals ions
above. DQPMA, also a known compound, and DQPEA were synthesized and characterized to
improve the selectivity and solubility of sensors.
Three aspects characterizing the ligands were explored in this work. Crystals of Zn2+-
DQPEA and Cd2+-DQPEA were grown and their crystal structures were determined. The pKa’s
of DQPMA and DQPEA were then determined by potentiometry and NMR. Finally, the
formation constants of DQPMA and DQPEA with the metal ions above were determined by
polarography and fluorescence techniques. It was proved in this study that the selectivities of the
sensors, DQPMA and DQPEA, for small metal ions such as Zn2+ over big metal ions such as
Cd2+do increase when one of chelate ring increases from the five membered (Zn2+-DQPMA) to
the six membered (Zn2+-DQPEA).
Synthesis and design of fluorescence ligands to act as sensor for zinc
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Created on 1/1/2009
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Additional Information
- Publication
- Thesis
- A Thesis Submitted to the University of North Carolina at Wilmington in Partial Fulfillment Of the Requirements for the Degree of Master of Science
- Language: English
- Date: 2009
- Keywords
- Ligands (Biochemistry), Ligands--Synthesis, Zinc--Research
- Subjects
- Zinc -- Research
- Ligands (Biochemistry)
- Ligands -- Synthesis
Title | Location & Link | Type of Relationship |
Title page, table of contents and abstract | http://libres.uncg.edu/ir/uncw/f/ganw2004-1.pdf | The described resource includes the related resource either physically or logically. |
References | http://libres.uncg.edu/ir/uncw/f/ganw2004-3.pdf | The described resource includes the related resource either physically or logically. |
Appendices | http://libres.uncg.edu/ir/uncw/f/ganw2004-4.pdf | The described resource includes the related resource either physically or logically. |