Identification of multi-component metal ion mixtures in complex systems using fluorescence sensor arrays

Area of Science:

• Environmental Chemistry
• Nanotechnology
• Analytical Chemistry

Background:

• Co-contamination of multiple metal ions poses significant risks to human health.
• Rapid and accurate discrimination of heavy metal ions in complex aquatic systems is challenging.

Purpose of the Study:

• To develop a high-throughput fluorescence sensor array for simultaneous identification and quantification of seven heavy metal ions.
• To enable rapid detection of heavy metals in environmental waters with minimal sample pretreatment.

Main Methods:

• Fabrication of a fluorescence sensor array using three distinct gold nanoclusters (GSH-Au NCs, OVA-Au NCs, BSA-Au NCs).
• Utilizing distinct binding capacities of gold nanoclusters to induce unique fluorescence variations (enhancement and quenching).
• Integrating fluorescence fingerprints with linear discriminant analysis (LDA) and hierarchical cluster analysis (HCA) for data analysis.

Main Results:

• The sensor array successfully identified and quantified seven heavy metal ions (Pb2+, Fe3+, Cu2+, Co2+, Ag+, Hg2+, As3+).
• Achieved a limit of detection (LOD) at the nanomolar (nM) concentration level with high accuracy.
• Demonstrated a unique fluorescence pattern for each metal ion, enabling distinct recognition.

Conclusions:

• The developed fluorescence sensor array provides a sensitive and accurate platform for detecting multiple heavy metal ions in environmental waters.
• The system requires minimal sample pretreatment, making it suitable for real-time environmental monitoring.
• This approach offers a generalizable platform for the detection of various low-concentration targets in environmental samples.