title: Development of an on-line temperature-assisted ionic liquid dispersive microextraction system for sensitive determination of vanadium in environmental and biological samples.
abstract: An original flow injection (FI) system was developed for on-line microextraction of Vanadium (V) based on room temperature ionic liquid (RTIL). Vanadium was complexed with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) at pH 4.0. A 40 microL-volume of 1-butyl-3-methylimidazolium hexafluorophosphate ([C(4)mim][PF(6)]) RTIL was mixed with 5 mL of sample solution containing the V-5-Br-PADAP complex. Then, a fully on-line temperature-assisted dispersion procedure was developed, followed by, analyte microextraction; and final on-line separation of the RTIL phase with a florisil-containing microcolumn. Vanadium was removed from the microcolumn with a 10% (v/v) nitric acid (in acetone) solution, and finally measured by electrothermal atomic absorption spectrometry (ETAAS). The detection limit achieved after preconcentration of 5 mL of sample solution, was 4.8 ng L(-1). The relative standard deviation (RSD) for 10 replicate determinations at 5 microg L(-1) of vanadium level was 4.1%, calculated from the obtained peak heights. The calibration graph was linear, with a correlation coefficient of 0.9982 at levels from the detection limits up to 15 microg L(-1). The method was successfully applied for the determination of vanadium in environmental and biological samples.
authors.affiliation: Analytical Chemistry Research and Development Group (QUIANID), LISAMEN-CCT-CONICET-Mendoza, Av. Ruiz Leal S/N Parque General San Martín, M 5502 IRA Mendoza, Argentina.
authors.forename: Paula
authors.initials: P
authors.lastname: Berton
authors.forename: Estefanía M
authors.initials: EM
authors.lastname: Martinis
authors.forename: Rodolfo G
authors.initials: RG
authors.lastname: Wuilloud
mesh_terms: D002138:Calibration; D005591:Chemical Fractionation / Q000379:methods; D004785:Environmental Pollutants / Q000032:analysis* / Q000302:isolation & purification; D052578:Ionic Liquids; D057230:Limit of Detection; D015203:Reproducibility of Results; D013054:Spectrophotometry, Atomic / Q000379:methods; D013696:Temperature; D014639:Vanadium / Q000032:analysis* / Q000302:isolation & purification
chemical_list: D004785:Environmental Pollutants; D052578:Ionic Liquids; D014639:Vanadium