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Updated: Jun 3, 2026
05:15
An Aptamer-based Sensor for Unchelated Gadolinium(III)
Published on: January 9, 2017
[Gd(Try-TTDA)(H2O)]2-: a new MRI contrast agent for copper ion sensing
Dayananda Kasala1, Tsung-Sheng Lin, Chiao-Yun Chen
1Department of Biological Science and Technology, National Chiao Tung University, 75 Bo-Ai Street, Hsinchu 300, Taiwan.
Dalton Transactions (Cambridge, England : 2003)
|April 1, 2011
Summary
Researchers developed novel L-tryptophan based contrast agents for MRI. One agent, [Gd(Try-TTDA)(H(2)O)](2-), acts as a selective Cu(II) sensor, showing significant signal changes and fluorescence quenching upon copper ion detection.
Area of Science:
- * Development of novel contrast agents for advanced medical imaging.
- * Exploration of L-tryptophan based gadolinium (Gd(III)) complexes.
- * Investigation of metal ion interactions and sensing capabilities.
Background:
- * Gadolinium (Gd(III)) complexes are widely used as MRI contrast agents.
- * L-tryptophan offers unique properties for developing smart contrast agents.
- * Copper (Cu(II)) dysregulation is implicated in various diseases, necessitating sensitive detection methods.
Purpose of the Study:
- * To synthesize and characterize two new L-tryptophan based Gd(III) contrast agents.
- * To evaluate the response of these agents to Cu(II) addition, focusing on relaxivity and fluorescence.
- * To assess the selectivity and potential of the developed agents as Cu(II) sensors for MRI.
Main Methods:
- * Synthesis of two Gd(III) complexes: [Gd(Try-TTDA)(H(2)O)](2-) and [Gd(Try-ac-DOTA)(H(2)O)](-).
- * Relaxivity (r(1)) measurements upon addition of Cu(II).
- * Fluorescence spectroscopy to study the interaction of Cu(II) with the indole ring.
- * Selectivity tests against other metal ions (La(III), Mg(II)).
- * In vitro MRI experiments to assess imaging signal intensity.
Main Results:
- * [Gd(Try-TTDA)(H(2)O)](2-) showed significant increases in relaxivity and hydration number with Cu(II) addition.
- * [Gd(Try-ac-DOTA)(H(2)O)](-) exhibited only a minor change in relaxivity with Cu(II).
- * Indole fluorescence of [Gd(Try-TTDA)(H(2)O)](2-) was completely quenched by one equivalent of Cu(II).
- * [Gd(Try-TTDA)(H(2)O)](2-) demonstrated high selectivity for Cu(II) over La(III) and Mg(II).
- * In vitro MR imaging showed significant signal intensity with [Gd(Try-TTDA)(H(2)O)](2-) in the presence of Cu(II).
Conclusions:
- * [Gd(Try-TTDA)(H(2)O)](2-) functions as a responsive and selective Cu(II) sensor.
- * The developed L-tryptophan based contrast agent holds promise for Cu(II) detection via MRI.
- * This novel agent offers a potential tool for MR imaging-based diagnostics involving copper ions.
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