Chemometrically driven multiplexed metal ion detection using a triple emitting quantum dots-based nanoprobe.

Area of Science:

• Environmental Science
• Analytical Chemistry
• Materials Science

Background:

• Metal ion pollution is a global environmental and health concern, with synergistic toxicity.
• Simultaneous quantification of multiple metal ions is challenging but crucial for accurate risk assessment.
• Existing methods often lack the speed, accuracy, or cost-effectiveness required for widespread monitoring.

Purpose of the Study:

• To develop a novel, accurate, and rapid method for simultaneous detection of eleven common metal ions.
• To utilize a triple-emission nanoprobe for enhanced multiplexed sensing capabilities.
• To apply advanced chemometric tools for analyzing photoluminescence data and improving quantification accuracy.

Main Methods:

• Fabrication of a triple-emission nanoprobe using carbon dots and capped CdTe quantum dots (green-emitting glutathione-QDs and red-emitting 3-mercaptopropionic acid-QDs).
• Simultaneous detection of Ag+, Cu2+, Hg2+, Al3+, Pb2+, Fe3+, Fe2+, Zn2+, Ni2+, Cd2+, and Ca2+.
• Analysis of first- and second-order photoluminescence (PL) data using partial least squares (PLS) and unfolded partial least squares (U-PLS) chemometric models.

Main Results:

• High accuracy (R2P > 0.9) achieved for several metal ions at low concentrations (mmol L-1) using advanced chemometric analysis.
• Second-order PL data provided superior results compared to first-order data due to time-dependent metal ion interactions.
• First-time observation of the significant impact of metal ion molar ratios on model accuracy.

Conclusions:

• The developed nanoprobe and chemometric approach offers a highly accurate and efficient solution for simultaneous multi-metal ion detection.
• This method enhances environmental monitoring capabilities and contributes to understanding complex mixed metal ion systems.
• The findings pave the way for earlier detection and mitigation of metal ion contamination threats, safeguarding environmental and human health.