A bifunctional sensor based on Au-Fe3O4 nanoparticle for the detection of Cd2+

A bifunctional sensor based on Au-Fe3O4 nanoparticles (NPs) modified by ethyl 1-(2-(3′,4′-dihydroxyphenyl)-2-oxoethyl)-1H-1,2,3-triazole-4-carboxylate (ETC) was developed. Due to the coordination interaction between cadmium (Cd2+) and ETC, Cd2+ induced the aggregation of Au-Fe3O4 NPs from dispersion, concomitant with a change in UV-vis spectra and transverse relaxation time (T2). The combined signals provided high selectively for Cd2+ ions.