A pyridine-containing Cu²⁺-selective probe based on naphthalimide derivative

Area of Science:

• Analytical Chemistry
• Organic Chemistry
• Materials Science

Background:

• Copper ions (Cu2+) play crucial roles in biological processes but elevated levels can be toxic.
• Developing selective and sensitive methods for Cu2+ detection is essential for environmental monitoring and biological studies.
• Fluorescent probes offer advantages like high sensitivity and real-time detection capabilities.

Purpose of the Study:

• To synthesize and characterize a new fluorescent probe (P) for selective Cu2+ detection.
• To evaluate the probe's sensitivity, selectivity, and detection limit in aqueous media.
• To establish optimal conditions for Cu2+ quantification using the developed probe.

Main Methods:

• Synthesis and characterization of a naphthalimide-based fluorescent probe (P) with a pyridine group.
• Spectroscopic analysis (UV-Vis and fluorescence) to determine probe-environment interactions.
• Optimization of reaction conditions (pH, solvent composition) for Cu2+ sensing.
• Determination of linear response range and detection limit for Cu2+.

Main Results:

• Successful synthesis and characterization of fluorescent probe P.
• Probe P exhibited high selectivity and sensitivity towards Cu2+ in aqueous solutions.
• A linear response of probe P (2 μM) to Cu2+ was observed in the range of 0.05-0.9 μM under optimized conditions (ethanol-water, pH 7.4).
• The detection limit for Cu2+ was determined to be as low as 0.03 μM.

Conclusions:

• The synthesized naphthalimide-based probe P is a highly selective and sensitive chemosensor for Cu2+.
• Probe P demonstrates potential for accurate quantification of Cu2+ in environmental or biological samples.
• The low detection limit and good linear response highlight the probe's utility in trace metal analysis.