title: Dispersive Liquid-Liquid Microextraction Using Low-Toxic Solvent for the Determination of Heavy Metals in Water Samples by Inductively Coupled Plasma-Mass Spectrometry.
abstract: A low-toxic dispersive liquid-liquid microextraction (DLLME) combined with inductively coupled plasma-MS was used for preconcentration and determination of Cu, Cr, Cd, Ni, Mn, and Pb in real-water samples. In traditional DLLME analysis, chlorinated solvents have been widely used as extraction solvents. However, these solvents are not environmentally friendly. To overcome this problem, we used a low-toxic bromosolvent (1-bromo-3-methylbutane; lethal concentration, 50%, 6150 mg/kg) as the extraction solvent. To study the effects of different parameters on the extraction efficiency, an orthogonal array experimental design with an L16(4(5)) matrix was used. Under the best experimental conditions (i.e., concentration of complexing reagent 1-(2-pyridylazo)-2-naphthol, 1.5 × 10(-3) mol/L; pH, 7.0; volume of acetone, 0.5 mL; volume of 1-bromo-3 methylbutane, 30 μL; and without salt addition), the enhancement factor ranged from 34 to 40. The linear dynamic range was 1-1000 μg/L with r(2) values of 0.9984-0.9999, and the LODs were between 0.042 and 0.53 μg/L. RSDs (at metal ion concentrations of 20 μg/L, n = 6) were 2.12 to 3.42%. The developed method was successfully applied to the extraction and determination of the mentioned metal ions in real-water samples, and satisfactory results were obtained.
authors.affiliation: Chongqing University, Key Laboratory of Eco-Environment of Three Gorges Region of Ministry of Education, Chongqing 400045, China.
authors.forename: Guilong
authors.initials: G
authors.lastname: Peng
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.forename: Qiang
authors.initials: Q
authors.lastname: He
authors.forename: Daniel
authors.initials: D
authors.lastname: Mmereki
authors.forename: Guangming
authors.initials: G
authors.lastname: Zhou
authors.forename: Junhua
authors.initials: J
authors.lastname: Chen
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Tang
mesh_terms: D006842:Hydrocarbons, Brominated / Q000737:chemistry*; D059627:Liquid Phase Microextraction; D013058:Mass Spectrometry; D019216:Metals, Heavy / Q000032:analysis*; D012997:Solvents / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D006842:Hydrocarbons, Brominated; D019216:Metals, Heavy; D012997:Solvents; D014874:Water Pollutants, Chemical