title: Ionic liquid-based single drop microextraction of ultra-trace copper in food and water samples before spectrophotometric determination.
abstract: In this work, room temperature ionic liquid (RTIL) 1-butyl-3-methylimidazolium hexafluorophosphate ([C4mim]PF6) was used as extractant in single drop microextraction (SDME). The traditionally volatile organic extractants were substituted by this green reagent, which changed SDME preconcentration into environmentally friendly method, relatively. After this pretreatment, ultra-trace copper in water and food samples could be accurately detected by spectrophotometer. This study was focused on the improvement of the analytical performance of spectrophotometric determination, expanding its applications. The influence factors relevant to IL-SDME, such as absorption spectra of complex, drop volume of RTIL, stirring rate and time, concentration of chelating agent, pH, and salt effect were studied systematically. Under the optimal conditions, the limit of detection (LOD) was 0.15 μg L(-1) with an enhancement factor (EF) of 33. The proposed method was green, simple, rapid, sensitive, and cost-efficient.
authors.affiliation: College of Pharmacy and Chemistry, Dali University, Dali, Yunnan 671000, China. wenxdong129@163.com
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Wen
authors.forename: Qingwen
authors.initials: Q
authors.lastname: Deng
authors.forename: Jie
authors.initials: J
authors.lastname: Guo
mesh_terms: D000818:Animals; D003300:Copper / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007093:Imidazoles / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry*; D057230:Limit of Detection; D008892:Milk / Q000737:chemistry*; D013053:Spectrophotometry; D013662:Tea / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: C412621:1-butyl-3-methylimidazolium hexafluorophosphate; D007093:Imidazoles; D052578:Ionic Liquids; D013662:Tea; D014874:Water Pollutants, Chemical; D014867:Water; D003300:Copper