title: Determination of lead and cadmium using an ionic liquid and dispersive liquid-liquid microextraction followed by electrothermal atomic absorption spectrometry.
abstract: A procedure for the determination of ultratrace levels of lead and cadmium using dispersive liquid-liquid microextraction followed by electrothermal atomic absorption spectrometry (ETAAS) has been developed. The ionic liquid, 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C8MIm][NTf2]), is formed in situ and used to extract the lead and cadmium complexes with ammonium pyrrolidinedithiocarbamate. The very fine droplets of ([C8MIm][NTf2]) allow effective dispersion without the need for organic solvents. After centrifugation, the concentrations of lead and cadmium in the sedimented phase can be determined by ETAAS. Using a 10 mL aqueous sample, the enrichment factor of the procedure was 280 and detection limits of 0.2 and 3 ng L(-1) were obtained for cadmium and lead, respectively. The relative standard deviations for 10 replicates at the 10 ng L(-1) cadmium and 0.2 μg L(-1) lead levels were 6.5 and 7.3%, respectively. The method was successfully applied to the analysis of waters as well as to lixiviates obtained from toys made of plastic materials.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Regional Campus of International Excellence Campus Mare Nostrum, University of Murcia, Murcia, Spain.
authors.forename: Ignacio
authors.initials: I
authors.lastname: López-García
authors.forename: Yesica
authors.initials: Y
authors.lastname: Vicente-Martínez
authors.forename: Manuel
authors.initials: M
authors.lastname: Hernández-Córdoba
mesh_terms: D002104:Cadmium / Q000032:analysis*; D052578:Ionic Liquids; D007854:Lead / Q000032:analysis*; D059627:Liquid Phase Microextraction / Q000379:methods*; D013054:Spectrophotometry, Atomic / Q000379:methods*
chemical_list: D052578:Ionic Liquids; D002104:Cadmium; D007854:Lead