A highly sensitive coumarin-thiophene hybrid chemosensor for sensing of H2O2 and aluminium

Abstract A highly sensitive coumarin-thiophene hybrid chemosensor (CZT) has been successfully designed for sensing of H2O2 and aluminium ion in physiological condition. A large stoke shift and significant enhancement in fluorescence spectra was recorded at λem = 505 nm when sensor was tested with hydrogen peroxide. In the sensing of H2O2, increase in emission peak was linearly depend on concentration of hydrogen peroxide in the range of 50 μM to 2.0 mM which results the detection limit of 1.5 × 10−7 M. Furthermore, colorimetric and spectrophotometric studies reveal that reported sensor had potential to sense Al3+ ion selectively over other tested competitive cations and sensitivity for Al3+ was not affected by coexistent of tested metal ions with detection limit of 1.14 × 10−6 M which is lower than WHO recommendation. The Job's continuation variation plot demonstrated that sensor CZT binds with Al3+ ion via 1:1 binding stoichiometry.