Abstract

In the current study, the conditions for electrothermal atomic absorption determination of Pb(II) with a graphite “filter-furnace” atomizer (GFF) in the presence of a “universal” chemical modifier – a mixture of palladium and magnesium nitrates (Pd-Mg CM) have been studied and optimized. It has been shown that the use of GFF with Pd-Mg CM allows the temperature at the ashing stage to be raised to 900 °C, and at the atomization stage to 2100 °C, which contributes to more efficient mineralization of the analyzed samples and also leads to an increase in the sensitivity of Pb determination by approximately 1.5 times compared to the technique of evaporation from the furnace wall. A method for direct electrothermal atomic absorption determination of Pb(II) has been developed. The calibration graph is linear in the concentration range of 0.005-0.1 mg/dm³, and the limits of detection and quantification are 0.0008 and 0.0028 mg/dm³, respectively. The proposed method is in good agreement with the results obtained using the standard method, which indicates its suitability for the determination of Pb(II) in dairy products, and the relative standard deviation does not exceed 6.4%.

Keywords: Lead(II), direct determination, electrothermal atomic absorption spectrophotometry, graphite «filter-furnace», chemical modifier

Article language: Uk