Supramolecular Graphene Quantum Dots/Porphyrin Complex as Fluorescence Probe for Metal Ion Sensing
Mariachiara Sarà1, Andrea Romeo1,2, Gabriele Lando1
1Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, University of Messina, V.le F. Stagno D'Alcontres, 31, 98166 Messina, Italy.
International Journal of Molecular Sciences
|August 14, 2025
Summary
This study developed a graphene quantum dot-porphyrin supramolecular adduct (GQDs@TPPS4) for sensitive metal ion detection. The adduct shows enhanced metalation rates and can detect Cu2+, Hg2+, and Cd2+ ions.
Area of Science:
- Materials Science
- Nanotechnology
- Analytical Chemistry
Background:
- Graphene quantum dots (GQDs) are stable, emissive, water-soluble nanomaterials.
- Positively charged GQDs interact with negatively charged porphyrins like TPPS4.
- Supramolecular chemistry offers novel functional materials.
Purpose of the Study:
- To synthesize and characterize a GQDs@TPPS4 supramolecular adduct.
- To investigate the metalation kinetics and optical properties of the adduct.
- To evaluate the adduct's potential for metal ion sensing.
Main Methods:
- Microwave-induced pyrolysis for GQD synthesis.
- Stoichiometric control for GQDs@TPPS4 adduct formation.
- UV/Vis spectroscopy and fluorescence emission analysis for metal ion detection.
Main Results:
- The GQDs@TPPS4 adduct exhibits dual fluorescence emission.
- Metalation rates of Cu2+ ions were accelerated three-fold.
- Sensitive detection of Cu2+, Hg2+, and Cd2+ ions was achieved with linear behavior in the micromolar range.
Conclusions:
- The GQDs@TPPS4 adduct is a promising platform for metal ion sensing.
- The adduct's optical properties are modulated by metal ion interactions.
- This supramolecular system demonstrates enhanced metalation kinetics.
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