Salicylaldehyde-functionalized gold-nanocluster-based Ratiometric fluorescent sensor Array for metal-ion detection

Area of Science:

• Environmental Science
• Analytical Chemistry
• Nanotechnology

Background:

• Heavy metal ions in aquatic environments pose significant challenges for detection due to their co-occurrence.
• Conventional fluorescent probes struggle with multiplex discrimination of metal ions using specific recognition mechanisms.

Purpose of the Study:

• To develop a dual-channel ratiometric fluorescent sensor array for discriminating ten different metal ions.
• To enable the reliable detection and quantification of multicomponent heavy metal mixtures in aqueous environments.

Main Methods:

• Construction of a sensor array using salicylaldehyde (SA)-functionalized, protein-stabilized gold nanoclusters (AuNCs).
• Utilizing distinct ratiometric fluorescence response patterns for pattern recognition.
• Applying principal component analysis (PCA), linear discriminant analysis (LDA), and the ExtraTrees model for classification and quantification.

Main Results:

• The sensor array successfully discriminated ten metal ions (Zn²⁺, Hg²⁺, Co²⁺, Pb²⁺, Ag⁺, Cu²⁺, Fe²⁺, Fe³⁺, Ni²⁺, Mn²⁺) at concentrations as low as 0.5 μM.
• Reliable classification and discrimination of multicomponent heavy metal mixtures were achieved.
• The ExtraTrees model enhanced concentration-independent classification and quantitative prediction.

Conclusions:

• The developed sensor array demonstrates high potential for practical monitoring of multiple heavy metal ions in complex aquatic environments.
• The array offers a robust platform for multiplex heavy metal detection, overcoming limitations of traditional methods.
• This technology can contribute to improved environmental water quality assessment and management.