Photophysical and Physicochemical Investigation of Newly Synthesized Polycyclic Pyrazoline-Benzothiazole as Fluorescence Chemosensor for the Detection of Cu²⁺ Metal Ion

Abstract

The title compound 2-(3-(2,5-dimethylfuran-3-yl)-5-(9-ethyl-9H-carbazol-3-yl)-4,5-dihydro-1H-pyrazol-1-yl)benzo[d]thiazole (DEPT) was synthesized by the reaction of 2-hydrazinobenzothiazole with chalcone (DFCP). The structure of the DEPT was established by the spectroscopic techniques and elemental analysis. Photophysical and physicochemical properties of the DEPT chromophore was studied by absorption and fluorescence spectroscopy. The optical properties of newly synthesized DEPT chromophore were depended on the different polarity of the solvents. Effects of two surfactants cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) of the DEPT chromophore were studied and suggested that, it can be used as probe to determine the critical micelle concentration of the CTAB and SDS surfactants. Moreover, DEPT chromophore can be used as fluorometric detection of selective Cu²⁺ metal ion. According to the obtained data, the fluorescence intensity of the DEPT was decreased intensity of the fluorescence spectra significantly by the concentration dependent manner. So the DEPT can be used as on to off fluorescence chemosensor for the detection of Cu²⁺ metal ion. Quenching behavior was explained by the Benesi-Hildebrand and Stern-Volmer mechanism.

Keywords:

• Pyrazoline
• optical properties
• sensor
• metal ion

Acknowledgements

The authors, therefore, acknowledge with thanks DSR for technical and financial support.

Additional information

Funding

This project was funded by the deanship of Scientific Research (DSR) at King Abdulaziz University, Jeddah, under grant number G-488-130-1439.