Determination of Nickel in Food Samples by Flame Atomic Absorption Spectroscopy after Preconcentration and Microextraction Based Ionic Liquids Using Full Factorial and Central Composite Design
Article first published online: 31 JUL 2012
© 2012 Institute of Food Technologists®
Journal of Food Science
Volume 77, Issue 12, pages C1242–C1248, December 2012
How to Cite
Zarei, Z. and Shemirani, F. (2012), Determination of Nickel in Food Samples by Flame Atomic Absorption Spectroscopy after Preconcentration and Microextraction Based Ionic Liquids Using Full Factorial and Central Composite Design. Journal of Food Science, 77: C1242–C1248. doi: 10.1111/j.1750-3841.2012.02820.x
- Issue published online: 13 DEC 2012
- Article first published online: 31 JUL 2012
- MS 20111398 Submitted 11/19/2011, Accepted 5/23/2012.
- central composite design;
- ionic liquid;
- in situ solvent formation microextraction;
- microsample introduction;
Abstract: In this research, a microextraction technique based on ionic liquids (ILs) termed in situ solvent formation microextraction (ISFME) was used for determination of nickel in solutions. 1-(2-pyridylazo)-2-naphtol (PAN) was chosen as a complexing agent. After preconcentration, the settled IL-phase was dissolved in 50 μL of ethanol and aspirated into the flame atomic absorption spectrometer (FAAS) using a home-made microsample introduction system. Injection of 50 μL volumes of analyte into an air–acetylene flame provided very sensitive spike-like and reproducible signals.
ISFME is based on phase separation phenomenon of ionic liquids in aqueous solutions. This method is simple and rapid for extraction and preconcentration of metal ions from food samples and can be applied for the sample solutions containing very high concentrations of salt. Furthermore, this technique is much safer in comparison with the organic solvent extraction because of using ionic liquid.
The effective parameters such as amount of IL, salt effect, concentration of the chelating agent and ion pairing agent were inspected by a full factorial design to identify important parameters and their interactions. Next, a central composite design was applied to obtain optimum point of the important parameters. Under the optimum conditions, the calibration graph was linear over the range of 2 to 80 ng/mL. The limit of detection and relative standard deviation (n= 6) were 0.6 ng/mL and 2%, respectively.