A Highly Selective and Sensitive Turn-on Fluorescent Probe for Al³⁺ Detection: Properties and Applications

Area of Science:

• Analytical Chemistry
• Materials Science
• Biochemistry

Background:

• Aluminum ions (Al³⁺) play crucial roles in biological and environmental systems.
• Accurate detection of Al³⁺ is vital for understanding its physiological and pathological implications.
• Development of selective and sensitive fluorescent probes is essential for Al³⁺ monitoring.

Purpose of the Study:

• To synthesize and characterize a novel fluorescent probe for selective Al³⁺ detection.
• To investigate the sensing mechanism of the probe.
• To evaluate the probe's applicability in real-world samples and bioimaging.

Main Methods:

• Synthesis of (2-hydroxy-5-methylbenzylidene)picolinohydrazide (HMPC) based on hydrazide Schiff base.
• Fluorescence spectroscopy for Al³⁺ detection and selectivity studies.
• Density Functional Theory (DFT) calculations to elucidate sensing mechanisms.

Main Results:

• HMPC exhibited remarkable selectivity and enhanced fluorescence emission towards Al³⁺.
• The probe's response is attributed to intramolecular proton transfer and charge transfer effects.
• Low detection limits (1.87 × 10⁻⁸ M in acetonitrile) were achieved.
• Successful application in detecting Al³⁺ in actual samples and intracellular imaging.

Conclusions:

• HMPC is a highly selective and sensitive fluorescent probe for Al³⁺ detection.
• The probe demonstrates potential for environmental monitoring and biological studies.
• HMPC offers a practical tool for on-site Al³⁺ detection using smartphones and bioimaging.