Optical fiber fluorescence Cu²⁺ sensing technology based on CdSe/ZnS quantum dots: Large detection range, low...

Area of Science:

• Materials Science
• Environmental Science
• Analytical Chemistry

Background:

• Copper ion (Cu2+) imbalances impact human health and ecosystems.
• Existing Cu2+ sensors have limitations in detection range, detection limits, cost, and preparation complexity.
• There is a need for advanced Cu2+ sensors for real-time environmental monitoring.

Purpose of the Study:

• To design and fabricate a high-performance optical fiber fluorescent sensor for Cu2+ detection.
• To overcome the limitations of current Cu2+ sensing technologies.
• To enable cost-effective, real-time monitoring of Cu2+ in environmental samples.

Main Methods:

• Fabrication of an optical fiber sensor using polyethylene glycol diacrylate (PEGDA) hydrogel encapsulated CdSe/ZnS quantum dots (QDs).
• Utilizing the porous nature of PEGDA hydrogels for selective Cu2+ permeation and interaction with QDs.
• Employing fluorescence quenching of QDs upon reaction with Cu2+ for quantitative analysis.

Main Results:

• The sensor achieved a quantitative detection range of 0.1-200 μM for Cu2+.
• A low limit of detection (LOD) of 0.8 nM was recorded.
• The sensor demonstrated a rapid response time of 5 seconds, strong specificity, and successful application in real water samples.

Conclusions:

• The developed sensor offers a large detection range and a low LOD for Cu2+.
• The synthesis of the core fluorescent probe is straightforward and rapid (approx. 2 min UV irradiation).
• This technology holds significant potential for real-time Cu2+ monitoring, especially in confined environments.