A Novel Mercury-Sensitive Fluorescent Nano-chemosensor using new Functionalized Magnetic core-shell Fe3O4@SiO2 Nanoparticles

Document Type: Original Research Paper

Authors

1 Department of life science engineering, Faculty of New Sciences & Technologies, University of Tehran, Tehran, Iran

2 Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran, Iran

3 Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 14176, Iran

4 Department of Chemistry, Razi University, Kermanshah, Iran

5 Faculty of New Sciences & Technologies, University of Tehran, Tehran, Iran

Abstract

In this work, a novel Hg2+ sensitive fluorescent chemosensor is constructed. The proposed
nano-chemosensor was prepared through the preparation of 3-(benzo[d]thiazol-2-yl)-7-hydroxy-2H-chromen-
2-one functionalized silica nanoparticles which has high magnetization properties (BTC-Fe3O4@SiO2). The
ûnal product was characterized by Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric
analysis (TGA), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and UVvisible
absorption and ûuorescence emission. The material was found to demonstrate selective interactions
with Hg2+ ions. This interaction is most probably due to the presence of the ûuorophore moiety at the surface
of nanomaterial. Fluorescence measurements revealed that the emission intensity of the Hg2+-bound with the
magnetic core-shell Fe3O4@SiO2 NPs increases signiûcantly upon addition of various concentrations of Hg2+,
while in case of other mono, di, trivalent cations no changes or weak changes in the intensities were observed.
The enhancement of ûuorescence is attributed to the strong covalent binding of Hg2+ ions with the binding
constant value of 1.7×105/M. The sensor can be applied for analysis of mercury in environmental sample.

Keywords