An Ethyl-Thioglycolate-Functionalized Fe(3)O(4)@ZnS Magnetic Fluorescent Nanoprobe for the Detection of Ag(+) and Its Applications in Real Water Solutions.

Ethyl-thioglycolate-modified Fe(3)O(4)@ZnS nanoparticles (Fe(3)O(4)@ZnS-SH) were successfully prepared using a simple chemical precipitation method. The introduction of ethyl thioglycolate better regulated the surface distribution of ZnS, which can act as a recognition group and can cause a considerable quenching of the fluorescence intensity of the magnetic fluorescent nanoprobe, Fe(3)O(4)@ZnS-SH. Benefiting from stable fluorescence emission, the magnetic fluorescent nanoprobe showed a highly selective fluorescent response to Ag+ in the range of 0-400 μM, with a low detection limit of 0.20 μM. The magnetic fluorescent nanoprobe was used to determine the content of Ag(+) in real samples. A simple and environmentally friendly approach was proposed to simultaneously achieve the enrichment, detection, and separation of Ag(+) and the magnetic fluorescent nanoprobe from an aqueous solution. These results may lead to a wider range of application prospects of Fe(3)O(4) nanomaterials as base materials for fluorescence detection in the environment.