A highly selective, sensitive and reversible fluorescence chemosensor for Zn(2+) and its cell viability

Area of Science:

• Coordination Chemistry
• Materials Science
• Analytical Chemistry

Background:

• Schiff base ligands are versatile in coordination chemistry.
• Developing selective metal ion sensors is crucial for environmental and biological monitoring.
• Understanding ligand-metal interactions aids in designing functional materials.

Purpose of the Study:

• To synthesize and characterize a new imine conjugate Schiff base ligand (H2L).
• To evaluate the sensing capabilities of H2L for various metal ions.
• To investigate the structural and cytotoxic properties of the ligand and its metal complex.

Main Methods:

• Synthesis of Schiff base ligand H2L.
• UV-vis, fluorescence, and 1H NMR titration for sensing studies.
• Single crystal X-ray diffraction for structural analysis.
• Cytotoxicity assays against MCF-7 and A375 cell lines.

Main Results:

• H2L demonstrated selective 'turn-on' fluorescence sensing for Zn2+ among 18 metal ions.
• The detection limit for Zn2+ was determined to be 1.47 μM.
• X-ray studies confirmed the formation of a binuclear Zn2+ complex (1) and revealed unique 1D-polymeric chains in H2L due to C–H⋯C interactions.
• Both H2L and complex 1 exhibited marginal cytotoxicity.

Conclusions:

• The synthesized Schiff base ligand H2L is an effective fluorescent sensor for Zn2+.
• The structural analysis provides insights into ligand-metal binding and self-assembly.
• The low cytotoxicity suggests potential applications in biological systems.