title: Electrochemical platform based on nitrogen-doped graphene/chitosan nanocomposite for selective Pb2+detection.
abstract: A novel nanocomposite was developed and used for trace determination of Pb2+cations from aqueous solutions. The nanocomposite was obtained by the association of N-doped graphene (N-Gr) with a biocompatible polymer, namely chitosan (Ch). The characterization of the new nanocomposite material (Ch-N-Gr) was performed using TEM, STEM-EDX, SEM, XRD and XPS techniques. Compared with the bare gold electrode (GE) a remarkable enhancement of the voltammetric response of the modified electrode (Ch-N-Gr/GE) was always observed. Using the Ch-N-Gr/GE, the Pb2+voltammetric response showed a pair of well defined, quasi-reversible anodic and cathodic peaks, with the peak potentials located at about -0.59 V and -0.69 V, respectively. The calibration curves were obtained over a large linear range, from 10-7to 10-4M Pb2+concentration. Under optimized conditions, the detection limit was found to be 6.64 × 10-8M. The effect of several interfering species (such as other metallic cations or organic compounds of various concentrations) on the determination of Pb2+concentration was also studied, and the results proved the selectivity of the proposed modified electrode. The validity and effectiveness of the method was further confirmed by trace determination of Pb2+in real samples.
authors.affiliation: National Institute for Research and Development of Isotopic and Molecular Technologies, Donat Street, No. 67-103, RO-400293, Cluj-Napoca, Romania.
authors.forename: Lidia
authors.initials: L
authors.lastname: Magerusan
authors.forename: Crina
authors.initials: C
authors.lastname: Socaci
authors.forename: Maria
authors.initials: M
authors.lastname: Coros
authors.forename: Florina
authors.initials: F
authors.lastname: Pogacean
authors.forename: Marcela Corina
authors.initials: MC
authors.lastname: Rosu
authors.forename: Stefan
authors.initials: S
authors.lastname: Gergely
authors.forename: Stela
authors.initials: S
authors.lastname: Pruneanu
authors.forename: Cristian
authors.initials: C
authors.lastname: Leostean
authors.forename: Ioan Ovidiu
authors.initials: IO
authors.lastname: Pana