Preconcentration of lead using solidification of floating organic drop and its determination by electrothermal atomic absorption spectrometry

Abstract

A simple microextraction method based on solidification of a floating organic drop (SFOD) was developed for preconcentration of lead prior to its determination by electrothermal atomic absorption spectrometry (ETAAS). Ammonium pyrolidinedithiocarbamate (APDC) was used as complexing agent, and the formed complex was extracted into a 20 μL of 1-undecanol. The extracted complex was diluted with ethanol and injected into a graphite furnace. An orthogonal array design (OAD) with OA16 (45) matrix was employed to study the effects of different parameters such as pH, APDC concentration, stirring rate, sample solution temperature and the exposure time on the extraction efficiency. Under the optimized experimental conditions the limit of detection (based on 3 s) and the enhancement factor were 0.058 μg L−1 and 113, respectively. The relative standard deviation (RSD) for 8 replicate determinations of 1 μg L−1 of Pb was 8.8%. The developed method was validated by the analysis of certified reference materials and was successfully applied to the determination of lead in water and infant formula base powder samples.

Application of a thiourea‐containing task‐specific ionic liquid for the solid‐phase extraction cleanup of lead ions from red lipstick, pine leaves, and water samples

“…A comparison of the proposed method and some recently reported techniques for the separation and determination of Pb(II) is given in Table . As can be seen, this method presents acceptable figures of merit; low detection limit, high enrichment factor, and good linear range in comparison to the other methods.…”

Liquid-phase microextraction combined with graphite furnace atomic absorption spectrometry: A review

“…A C C E P T E D 111], Pb by SFODME [116], As by DLLME [15] and Se by DLLME [19]. Therefore, the sample obtained directly after digestion or with a very small dilution with ultrapure water or diluted acid (mainly 0.1 mol/L HCl or HNO 3 ) in order to achieve the desired pH can be directly subjected to the microextraction procedure.…”

“…[116]. An alternative procedure has been reported for Au determination in soils and sediments, involving ultrasound-assisted acid extraction with diluted HNO 3 + HCl prior to Au preconcentration by DLLME [157].…”

“…For powdered infant formula, the sample was burned in an electric heater and in a muffle furnace, and the residue was dissolved in HCl and HNO 3 [116]. Ultrasound-assisted extraction of Co from nutritional capsules was performed using water [115].…”

Determination of Cadmium and Lead in Water and Food by Organic Drop Microextraction and Flame Atomic Absorption Spectrometry

“…[12] Single solidified floating organic drop microextraction was developed modifying and improving the selectivity of the method. [13][14][15] However, in single solidified floating organic drop microextraction, only a few microliters of solvent is used for extraction of the analytes from aqueous samples, [16] reducing the use of organic solvents and associated purchase and disposal costs. [17,18] In this technique, solvents are employed that have melting point close to room temperature Multivariate techniques have been widely used in analytical chemistry because of their speed and low cost.…”