A coumarin-based fluorescent chemosensor as a Sn indicator and a fluorescent cellular imaging agent

Area of Science:

• Organic Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Development of selective and sensitive chemosensors is crucial for detecting specific ions.
• Coumarin derivatives offer versatile platforms for designing fluorescent probes.
• Tin ions (Sn2+) play roles in various industrial applications and biological processes, necessitating accurate detection methods.

Purpose of the Study:

• To synthesize and characterize novel fluorogenic coumarin-based probes.
• To investigate the photophysical properties and solvatochromism of the synthesized probes.
• To evaluate the selectivity and sensitivity of the probes for detecting various metal ions and anions, with a focus on tin ions.

Main Methods:

• Synthesis of coumarin-based probes (1-3) via condensation reactions.
• Spectroscopic analysis (absorption and fluorescence emission) in various solvents.
• Investigation of probe response to different cations and anions, including cytotoxicity assessment and cellular imaging.

Main Results:

• Probes 2b and 3 exhibited significant solvatochromic effects.
• Compound 3 demonstrated high selectivity for tin ions (Sn2+) via a chelation-enhanced quenching mechanism.
• The probe showed a low limit of detection (LOD) of 3.89 μM for Sn2+, with observable fluorescence quenching and colorimetric changes, and was found to be non-toxic in breast cancer cell lines.

Conclusions:

• The synthesized coumarin-based probe 3 is a highly selective and sensitive chemosensor for Sn2+ detection.
• The probe's ability to induce both fluorescence quenching and colorimetric changes offers versatile detection capabilities.
• The non-toxic nature and effectiveness in cellular imaging highlight its potential application in biological and environmental monitoring.