Polydiacetylene-based colorimetric and fluorometric sensors for lead ion recognition

Area of Science:

• Materials Science
• Analytical Chemistry
• Environmental Science

Background:

• Lead ions (Pb²⁺) pose significant risks to human health and ecosystems.
• Developing selective and sensitive detection methods for Pb²⁺ is crucial for environmental safety.

Purpose of the Study:

• To develop novel polydiacetylene (PDA)-based liposome sensors for the colorimetric and fluorometric detection of Pb²⁺.
• To functionalize PDA liposomes with thymine-1-acetic acid (TAA) or orotic acid (OA) for enhanced Pb²⁺ binding.
• To evaluate the selectivity, sensitivity, and real-world applicability of the developed sensors.

Main Methods:

• Incorporation of TAA- or OA-functionalized monomers and 10,12-pentacosadiynoic acid (PCDA) into PDA liposomes.
• UV light-induced polymerization to form blue-colored liposomes.
• Colorimetric and fluorometric analysis of liposome response to various metal cations, including Pb²⁺.

Main Results:

• PDA-liposome sensors exhibited a distinct color change from blue to red upon Pb²⁺ addition, visible to the naked eye.
• Significant fluorescence enhancement was observed in the presence of Pb²⁺.
• The sensors demonstrated high selectivity for Pb²⁺ over other transition metal ions.
• Detection limits were as low as 38 nM (TAA) and 25 nM (OA).
• Successful application in detecting trace Pb²⁺ in real water samples with high recovery rates.

Conclusions:

• The developed PDA-based liposome sensors (PDA-EDEA-TAA and PDA-EDEA-OA) are highly selective and sensitive probes for Pb²⁺ detection.
• The sensors offer a simple, rapid, and cost-effective method for monitoring Pb²⁺ in aqueous solutions and environmental samples.
• The findings highlight the potential of functionalized PDA liposomes for practical environmental analysis.