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Updated: Oct 5, 2025
16:11
Thermochemical Studies of NiII and ZnII Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
2.4K
Excited state dynamics of Zn-salophen complexes.
Patrick O'Keeffe1, Daniele Catone2, Stefano Turchini2
1Istituto di Struttura della Materia-CNR (ISM-CNR), EuroFEL Support Laboratory (EFSL), 00015, Monterotondo Scalo, Italy.
Summary
Zinc-salophen complexes act as fluorescent sensors for nucleotides. Upon addition of adenosine diphosphate (ADP), a Schiff base ligand is released, enabling selective ADP detection via enhanced fluorescence.
Area of Science:
- Coordination Chemistry
- Supramolecular Chemistry
- Analytical Chemistry
Background:
- Zinc-salophen complexes are explored as fluorescent chemosensors.
- Nucleotide and nucleic acid detection remains a key analytical challenge.
Purpose of the Study:
- Investigate the excited-state behavior of a Schiff base ligand (Sal) and its Zn(II) complex (Zn-Sal).
- Determine the interaction mechanism between Zn-Sal and adenosine diphosphate (ADP).
- Evaluate the potential of this system for selective ADP detection.
Main Methods:
- Steady-state UV-Vis absorption and fluorescence emission spectroscopy.
- Ultrafast transient absorption spectroscopy.
- Time-dependent density functional theory (TD-DFT) calculations.
Main Results:
- Sal ligand deactivates via excited-state torsional motion; Zn-Sal complexation induces rigidity.
- ADP addition to Zn-Sal results in a longer relaxation constant, indicating interaction.
- Extended incubation leads to demetallation and formation of 2,3-diamino naphthalene, causing enhanced fluorescence at 375 nm.
Conclusions:
- The interaction of Zn-Sal with ADP triggers demetallation of the Schiff base ligand.
- The fluorescent byproduct, 2,3-diamino naphthalene, allows for selective detection of ADP.
- This system shows promise as a fluorescent probe for adenosine diphosphate detection.
Keywords:
Adenosine diphosphateFluorescence emissionSalophenTime dependent density functional theoryUltrafast transient absorptionZincMore Related Videos
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