NiFe₂O₄ nanospheres functionalized with 2-(2, 4-Dihydroxyphenyl)-3, 5, 7-trihydroxychromen-4-one for selective...

Herein, a rational combination of dispersive solid-phase sorbent and 2-(2, 4-Dihydroxyphenyl)-3, 5, 7-trihydroxychromen-4-one (morin) was proposed for sensitive and selective determination of Al³⁺ ion. Nickel ferrite nanospheres (NiFe₂O₄ NS) functionalized with morin was used to preconcentrate and estimate Al³⁺ via the formation of fluorescent complex at pH 7.0. The functionalization was assisted by anionic surfactant sodium dodecyl sulphate (SDS) and ultrasonication. The results revealed that the fluorescence intensity of Al-morin/SDS@ NiFe₂O₄ NS is higher than Al-morin. Functionalization of NiFe₂O₄ NS with morin was confirmed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), powder X-ray diffractometer (PXRD), and fluorescence spectroscopy. Under the optimum conditions, the fluorescence intensity increased with increasing of Al³⁺ concentrations in the range of 0.28-500.0 ng mL^-1 with LOD (S/N = 3) of 0.09 ng mL^-1. The method was applied for the determination of Al³⁺ in natural waters and human serum samples with recoveries % of 97-104% and RSDs % of 2-4%.