title: Composite of Cu metal nanoparticles-multiwall carbon nanotubes-reduced graphene oxide as a novel and high performance platform of the electrochemical sensor for simultaneous determination of nitrite and nitrate.
abstract: In the present research, we aimed to fabricate a novel electrochemical sensor based on Cu metal nanoparticles on the multiwall carbon nanotubes-reduced graphene oxide nanosheets (Cu/MWCNT/RGO) for individual and simultaneous determination of nitrite and nitrate ions. The morphology of the prepared nanocomposite on the surface of glassy carbon electrode (GCE) was characterized using various methods including scanning electron microscopy (SEM), atomic force microscopy (AFM), and electrochemical impedance spectroscopy. Under optimal experimental conditions, the modified GCE showed excellent catalytic activity toward the electro-reduction of nitrite and nitrate ions (pH=3.0) with a significant increase in cathodic peak currents in comparison with the unmodified GCE. By square wave voltammetry (SWV) the fabricated sensor demonstrated wide dynamic concentration ranges from 0.1 to 75μM with detection limits (3Sb/m) of 30nM and 20nM method for nitrite and nitrate ions, respectively. Furthermore, the applicability of the proposed modified electrode was demonstrated by measuring the concentration of nitrite and nitrate ions in the tap and mineral waters, sausages, salami, and cheese samples.
authors.affiliation: Chemical Injuries Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran. Electronic address: h.bagheri@bmsu.ac.ir.
authors.forename: Hasan
authors.initials: H
authors.lastname: Bagheri
authors.affiliation: Laboratory for Sensors, Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges Köhler Allee 103, 79110 Freiburg, Germany.
authors.forename: Ali
authors.initials: A
authors.lastname: Hajian
authors.affiliation: Young Researchers and Elite Club, Hamedan Branch, Islamic Azad University, Hamedan, Iran.
authors.forename: Mosayeb
authors.initials: M
authors.lastname: Rezaei
authors.affiliation: Young Researchers and Elite Club, Hamedan Branch, Islamic Azad University, Hamedan, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Shirzadmehr
mesh_terms: D003300:Copper / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009566:Nitrates / Q000032:analysis*; D009573:Nitrites / Q000032:analysis*; D010087:Oxides
chemical_list: D037742:Nanotubes, Carbon; D009566:Nitrates; D009573:Nitrites; D010087:Oxides; D006108:Graphite; D003300:Copper
keywords: Cu metal nanoparticles; Electrochemical sensor; Graphene; Modified electrode; Multiwall carbon nanotubes; Nitrate and nitrite ions