Flavonol based surface modification of doped chalcogenide nanoflakes as an ultrasensitive fluorescence probe for Al 3+ ion.

A highly selective novel fluorescent probe was prepared by using surface modified ZnS:Mn nanoparticles, functionalized with morin, a flavonol. SEM investigations of the heterostructures prepared using wet chemical precipitation technique revealed a nanoflake type of morphology. HR-TEM and powder XRD analysis confirmed the crystalline planes corresponding to Wurtzite ZnS. The functionalized nanoparticles were characterized using Raman, XPS and FTIR which confirms the binding of morin to the nanoparticles via surface coordination. The prepared probe selectively interacts with Al3+ ions which has been used as an ultrasensitive analytical tool for determination of Al3+ ions. A major advantage of the proposed method is that the other metal ions closely associated with Al3+ did not interfere with the analysis. The detection limit and the quantitation limit were found to be 0.07 nM and 0.20 nM respectively with a linear dynamic range 0.20 nM-80 nM. The method was successfully applied to environmental water samples and other complex matrices.