Related Experiment Video
Updated: Sep 29, 2025
07:00
Accumulation and Analysis of Cuprous Ions in a Copper Sulfate Plating Solution
Published on: March 20, 2019
15.3K
Fluorogenic Detection of Sulfite in Water by Using Copper(II) Azacyclam Complexes
Carlo Ciarrocchi1, Donatella Sacchi1, Massimo Boiocchi2
1Dipartimento di Chimica, Università di Pavia, Via Taramelli 12, 27100 Pavia, Italy.
Molecules (Basel, Switzerland)
|March 26, 2022
Summary
Copper(II) azacyclam complexes are poor emitters, but decompose to release fluorescent subunits. This decomposition is accelerated by sulfite, enabling fluorogenic detection of sulfite in samples like wine.
Area of Science:
- Coordination Chemistry
- Analytical Chemistry
- Supramolecular Chemistry
Background:
- Copper(II) azacyclam complexes with emissive subunits are synthesized via template methods.
- The inherent fluorescence of these complexes is quenched by Cu(II) ions.
- Decomposition of the complex releases the emissive subunits, restoring fluorescence.
Purpose of the Study:
- To investigate the potential of Copper(II) azacyclam complexes as chemical probes.
- To develop a fluorogenic method for sulfite detection.
- To evaluate the method's applicability in real-world samples.
Main Methods:
- Template synthesis of Copper(II) azacyclam complexes with naphthyl or dansyl groups.
- Investigation of complex decomposition kinetics in the presence of sulfite.
- Fluorogenic detection of sulfite using the released subunits.
- Analysis of sulfite in white wine samples.
Main Results:
- Copper(II) azacyclam complexes exhibit poor fluorescence due to Cu(II) quenching.
- Complex decomposition and fluorescence recovery are accelerated by sulfite ions.
- The method successfully detected sulfite in laboratory settings and white wine.
- Sulfite concentration values in wine correlated well with standard analytical methods.
Conclusions:
- Copper(II) azacyclam derivatives serve as effective chemical probes for sulfite detection.
- The fluorogenic method offers a sensitive and reliable approach for sulfite quantification.
- This approach demonstrates potential for analyzing sulfite in complex matrices like beverages.
Related Concept Videos
01:17Precipitation and Co-precipitation
2.3K
Precipitation and coprecipitation methods can be used to separate a mixture of ions in a solution. In qualitative inorganic analysis, ions that form sparingly soluble precipitates with the same reagent are separated based on the differences in solubility products. For example, consider the separation of Cu(II) and Fe(II) ions by precipitation as insoluble sulfides. First, copper(II) sulfide is precipitated by the addition of acidic H2S, where the dissociation of H2S is suppressed. Adding H2S...
2.3K
01:19Precipitation Titration: Endpoint Detection Methods
2.2K
In argentometric precipitation titrations, endpoints can be detected visually by the Mohr, Volhard, and Fajans methods. In the Mohr method, adding a soluble chromate indicator gives an initial yellow color to the analyte solution. As the titrant is added, the first excess of silver ions forms a red silver chromate precipitate, marking the endpoint. The solution pH should be maintained at about 8 by adding solid CaCO3.
In the Volhard method, a standard excess of AgNO3 is first added to the...
In the Volhard method, a standard excess of AgNO3 is first added to the...
2.2K
01:11Aryldiazonium Salts to Azo Dyes: Diazo Coupling
3.1K
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the...
3.1K
03:45Formation of Complex Ions
24.1K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
24.1K
00:56Extraction: Advanced Methods
564
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is...
564