A new dispersive micro-solid phase extraction based on rejection property method combined with FAAS for the simultaneous determination of cobalt and copper after optimisation by Box-Behnken design

ABSTRACT

A new, fast and simple technique of dispersive micro-solid phase extraction based on rejection property (DMSPE-RP) combined with flame atomic absorption spectrometry (FAAS) for the simultaneous preconcentration and determination of trace amounts of cobalt and copper ions has been introduced. In this technique, 1-(2-pyridylazo)-2-naphthol (PAN) was used as a chelating agent and adsorbent. The experimental factors affecting the analytical performance of the method such as pH of the sample solution, the concentration of PAN and salting-out effect were evaluated and optimised using Box–Behnken design. Under the optimum conditions, the method exhibited linear dynamic ranges of 5.0–350.0 µg L⁻¹ for cobalt and 5.0–500.0 µg L⁻¹ for copper with the coefficients of determination higher than 0.997. The detection limits were 1.2 and 1.5 µg L⁻¹ and the enrichment factors were 184.0 and 154.0 for cobalt and copper, respectively. The accuracy of the method was evaluated by the analysis of water-certified reference material (TMDA 53.3 water). The results indicated that the presented method is a good technique for the determination of target metal ions in natural water samples.

KEYWORDS:

• Dispersive micro-solid phase extraction based on rejection property
• cobalt
• copper
• Box–Behnken design
• water samples

Acknowledgments

The support provided by Islamic Azad University of Arak (Arak, Iran) is highly appreciated.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Arak branch - Islamic Azad university.