SWASV performance toward heavy metal ions based on a high-activity and simple magnetic chitosan sensing nanomaterials

A high-activity, eco-friendly and inexpensive magnetic chitosan sensing nanomaterials were introduced for individual electrochemical detection toward Pb(II), Hg(II), Cu(II) and Cd(II) by square wave anodic stripping voltammetry (SWASV). The morphology and structure of Fe3O4-chitosan nanoparticles were characterized by TEM, XRD and FTIR respectively, and their electrochemical behavior based on the sensing materials modified glassy carbon electrode (GCE) was studied by cyclic voltammograms (CV) and electrochemical impedance spectra (EIS). Serving as a heavy metal ions sensor, the chitosan magnetic nanoparticles exhibited much more remarkable electrochemical response toward heavy metal ions. Especially, the introduction of chitosan significantly enhanced the SWASV performance toward Pb(II) with the high sensitivity of 50.6 mu A/mu M and LOD of 0.0422 mu M, which was about 4.8 times than pure Fe(3)O(4)nanoparticles. This result might be due to the strong charge-transfer interaction as well as the chelation and electrostatic interaction existence between Pb(II) and Fe3O4-chitosan unit, which will generate a high concentration region at electrode surface for efficient redox interaction between electrode and Pb(II). Furthermore, the Fe3O4-chitosan modified GCE offers good stability and potential practical applicability in the electrochemical determination of Pb(II). This work provides a potential simple and low cost material for electrochemical detection of toxic metal ions. (C) 2016 Elsevier B.V. All rights reserved.