a National Special Superfine Powder Engineering Research Center, Nanjing University of Science and Technology, Nanjing 210094, China

b School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China

摘要：In this work, a high-performance probe for Hg2+ detection has been successfully synthesized based on Rhodamine B isothiocyanate (RBI) and thioglycolic acid (TA) co-modified Fe3O4@Au nanocomposites. The probe has many favorable properties, including suitable size and magnetic response (46.28 emu/g). Importantly, the fluorescence changes of the probe are remarkably specific for Hg2+ in the presence of other competitive cations, and the limit of detection (LOD) for Hg2+ in aqueous solutions is lower (3.03 nM) than the value of the World Health Organization (30 nM), which meet the selective and sensitive requirements for practical application. Interestingly, due to the magnetic responsive performance of Fe3O4, the probe can be recycled by a magnet and reused by addition of free RBI into Fe3O4@Au solutions that were already used for Hg2+ detection. Furthermore, the experiments of probe for monitoring Hg2+ inside human umbilical vein endothelial (HUVEC) cells reveal that the probe has biocompatibility and low cytotoxicity, and can effectively detect Hg2+ in a short time. All the results presented in this study show that the proposed probe has significant potential for Hg2+ detection in environmental and biological samples.

關(guān)鍵詞：Hg2+; Fe3O4@Au nanocomposite; Targeted detection; Recyclable; Cell imaging