Sensitive fluorescence detection of Ni2+ ions using fluorescein functionalized Fe3O4 nanoparticles

摘要: This study describes a very sensitive fluorescence sensor for the selective nanomolar detection of Ni2+ ions. The ion sensing is based on quenching fluorophore (fluorescein) in neutral aqueous medium. composed magnetic core and amino silica shell, functionalized with fluorescein fluorophore. morphology, physical chemical properties materials were studied by FT-IR spectroscopy, X-ray powder diffraction, vibrating sample magnetometer (VSM) Transmission Electron Microscopy (TEM). UV-visible spectroscopy used to characterize nanoparticles. characterization measurements revealed that fluorescent nanostructures superparamagnetic nature an average particle diameter 10 nm. as-fabricated nanosensor (Fe3O4@SiO2-NH2-fluorescein) showed enhanced response towards ions pH was highly target species whereas possible interferences from other metal cations biological molecules negligible. probe has fast response, it limit (LOD = 0.83 nM) medium high binding constant (K) value 3.2 × 104 M−1 complex formation between These features ensure potential use nanomaterials as new class non-toxic biocompatible sensors environmental applications.