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An Aptamer-based Sensor for Unchelated Gadolinium(III)
Published on: January 9, 2017
A small-molecular europium complex with anion sensing sensitivity.
Jianwei Wang1, Jiang Wu, Yanmei Chen
1Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China.
Dalton Transactions (Cambridge, England : 2003)
|September 20, 2012
Summary
A new europium(III) complex with a quinoline derivative enables naked-eye detection of nitrate and chloride anions. This discovery offers a simple method for selective anion recognition through luminescence changes.
Area of Science:
- Coordination Chemistry
- Luminescent Materials
- Anion Sensing
Background:
- Europium(III) complexes are known for their luminescent properties.
- Developing selective sensors for anions like nitrate and chloride is crucial in various fields.
Purpose of the Study:
- To design and synthesize a novel small-molecular europium(III) complex for anion recognition.
- To investigate the complex's luminescent response to different anions.
Main Methods:
- Synthesis of a novel europium(III) complex with a quinoline derivative.
- Luminescence spectroscopy, UV-Vis titration, and Job plot analysis.
- X-ray crystallography to determine the complex structure.
Main Results:
- The europium(III) complex exhibits distinct luminescence changes at 616 nm upon binding with nitrate (NO(3)(-)) and chloride (Cl(-)) anions.
- Anion-selective luminescence enhancement is visible to the naked eye.
- Stable 1:1 complexes are formed with Eu(NO(3))(3) and EuCl(3) with high stability constants (log K = 7.10 and 6.76).
- Crystal structure reveals a semicircle-shaped coordination around the Eu(3+) ion, with available sites for guest anions.
Conclusions:
- The novel europium(III) complex acts as an effective sensor for nitrate and chloride anions.
- The luminescence enhancement mechanism is attributed to anions displacing solvent molecules from the coordination sphere.
- The complex offers a user-friendly, visually detectable method for anion sensing.
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