Multifunctional Schiff Base Chemosensor for Cu²⁺ and 2,4-D Sensing with Potent Antibacterial Activity

Area of Science:

• Chemical Sensing
• Materials Science
• Environmental Science

Background:

• Schiff base compounds are versatile for developing chemosensors.
• Photoinduced electron transfer (PET) mechanisms often limit fluorescence in chemosensors.
• Selective detection of environmental pollutants like 2,4-D and metal ions (Cu2+) is crucial.

Purpose of the Study:

• To synthesize a novel Schiff base chemosensor (SP1) for dual-mode detection of Cu2+ and 2,4-D.
• To investigate the sensing mechanism based on fluorescence and colorimetric changes.
• To evaluate the antibacterial properties of the synthesized chemosensor and its complex.

Main Methods:

• Synthesis of Schiff base chemosensor SP1.
• Fluorescence and UV-Vis spectroscopy for sensing mechanism elucidation.
• Detection limit determination for Cu2+ and 2,4-D.
• Antibacterial activity assay against pathogenic bacterial strains.

Main Results:

• SP1 exhibited a 'turn-on' fluorescence response and color change upon Cu2+ binding, inhibiting PET.
• The SP1-Cu2+ complex enabled 'turn-off' fluorescence sensing of 2,4-D with color recovery.
• High sensitivity achieved with detection limits of 0.003 ppm for Cu2+ and 0.02 ppm for 2,4-D.
• SP1 and its Cu2+ complex demonstrated significant antibacterial efficacy.

Conclusions:

• A novel dual-functional Schiff base chemosensor (SP1) was successfully developed.
• The chemosensor provides a sensitive and reliable platform for detecting Cu2+ and 2,4-D.
• The sensor exhibits potential for environmental monitoring and possesses antibacterial properties.