title: Cloud point extraction-flame atomic absorption spectrometry method for preconcentration and determination of trace cadmium in water samples.
abstract: A method based on cloud point extraction (CPE) separation/preconcentration of trace cadmium (Cd) as a prior step to its determination by flame atomic absorption spectrometry has been developed. Cadmium reacted with 8-hydroxyquinoline to form hydrophobic chelates, which were extracted into the micelles of nonionic surfactant oligoethylene glycol monoalkyl ether (Genapol X-080) in an alkaline medium. Octanol was used to depress the cloud point of Genapol X-080 in the extraction process. The chemical variables that affect the CPE, such as pH of complexation reaction, amount of chelating agent, Genapol X-080 and octanol were evaluated and optimized. Under optimized conditions, linearity was obeyed in the range of 10-500 μg/L, with the correlation coefficient of 0.9993. For 5 mL of sample solution, the enhancement factor was about 20. The limit of detection and limit of quantification of the method were 0.21 and 0.63 μg/L, respectively. The relative standard deviations (n = 6) was 3.2% for a solution containing 100 μg/L of Cd. The accuracy of the preconcentration system was evaluated by recovery measurements on spiked water samples. Recoveries of spiked samples varied in the range of 94.1-103.8%.
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Yunnan Province 650500, China E-mail: yilyil8@163.com.
authors.forename: Jinyan
authors.initials: J
authors.lastname: Ning
authors.affiliation: College of Architecture and City Planning, University of Wisconsin Madison, Madison, WI 53706, USA.
authors.forename: Yang
authors.initials: Y
authors.lastname: Jiao
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Yunnan Province 650500, China E-mail: yilyil8@163.com.
authors.forename: Jiao
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Yunnan Province 650500, China E-mail: yilyil8@163.com.
authors.forename: Lifen
authors.initials: L
authors.lastname: Meng
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Yunnan Province 650500, China E-mail: yilyil8@163.com.
authors.forename: Yaling
authors.initials: Y
authors.lastname: Yang
mesh_terms: D020003:1-Octanol / Q000737:chemistry; D002104:Cadmium / Q000032:analysis* / Q000737:chemistry; D002614:Chelating Agents / Q000737:chemistry; D008823:Micelles; D015125:Oxyquinoline / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D013054:Spectrophotometry, Atomic / Q000379:methods; D013501:Surface-Active Agents / Q000737:chemistry; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
chemical_list: D002614:Chelating Agents; D008823:Micelles; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical; D002104:Cadmium; D011092:Polyethylene Glycols; D015125:Oxyquinoline; C116996:genapol X 080; D020003:1-Octanol