title: Electrochemical sensors for the simultaneous determination of zinc, cadmium and lead using a Nafion/ionic liquid/graphene composite modified screen-printed carbon electrode.
abstract: A simple, low cost, and highly sensitive electrochemical sensor, based on a Nafion/ionic liquid/graphene composite modified screen-printed carbon electrode (N/IL/G/SPCE) was developed to determine zinc (Zn(II)), cadmium (Cd(II)), and lead (Pb(II)) simultaneously. This disposable electrode shows excellent conductivity and fast electron transfer kinetics. By in situ plating with a bismuth film (BiF), the developed electrode exhibited well-defined and separate peaks for Zn(II), Cd(II), and Pb(II) by square wave anodic stripping voltammetry (SWASV). Analytical characteristics of the BiF/N/IL/G/SPCE were explored with calibration curves which were found to be linear for Zn(II), Cd(II), and Pb(II) concentrations over the range from 0.1 to 100.0 ng L(-1). With an accumulation period of 120 s detection limits of 0.09 ng mL(-1), 0.06 ng L(-1) and 0.08 ng L(-1) were obtained for Zn(II), Cd(II) and Pb(II), respectively using the BiF/N/IL/G/SPCE sensor, calculated as 3σ value of the blank. In addition, the developed electrode displayed a good repeatability and reproducibility. The interference from other common ions associated with Zn(II), Cd(II) and Pb(II) detection could be effectively avoided. Finally, the proposed analytical procedure was applied to detect the trace metal ions in drinking water samples with satisfactory results which demonstrates the suitability of the BiF/N/IL/G/SPCE to detect heavy metals in water samples and the results agreed well with those obtained by inductively coupled plasma mass spectrometry.
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, Thailand.
authors.forename: Sudkate
authors.initials: S
authors.lastname: Chaiyo
authors.affiliation: Institute of Chemistry, Department of Analytical Chemistry, Karl-Franzens University, Universitätsplatz 1, Graz A-8010, Austria.
authors.forename: Eda
authors.initials: E
authors.lastname: Mehmeti
authors.affiliation: Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia.
authors.forename: Kristina
authors.initials: K
authors.lastname: Žagar
authors.affiliation: Department of Chemistry, Faculty of Science, Srinakharinwirot University, Sukhumvit 23, Wattana, Bangkok, Thailand. Electronic address: weena@swu.ac.th.
authors.forename: Weena
authors.initials: W
authors.lastname: Siangproh
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, Thailand; Center of Excellence on Petrochemical and Materials Technology, Chulalongkorn University, Patumwan, Bangkok, Thailand. Electronic address: corawon@chula.ac.th.
authors.forename: Orawon
authors.initials: O
authors.lastname: Chailapakul
authors.affiliation: Institute of Chemistry, Department of Analytical Chemistry, Karl-Franzens University, Universitätsplatz 1, Graz A-8010, Austria. Electronic address: kurt.kalcher@uni-graz.at.
authors.forename: Kurt
authors.initials: K
authors.lastname: Kalcher
keywords: Bismuth film; Cadmium; Lead; Nafion/ionic liquid/graphene composite; Screen-printed carbon electrode; Zinc