Development of Dispersive Liquid-Liquid Microextraction Based on Solidification of Floating Organic Drop for the Sensitive Determination of Trace Copper in Water and Beverage Samples by Flame Atomic Absorption Spectrometry

Abstract

A dispersive liquid-liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) has been developed as a new approach for the extraction of trace copper in water and beverage samples followed by the determination with flame atomic absorption spectrometry. In the DLLME-SFO, 8-hydroxy quinoline, 1-dodecanol, and methanol were used as chelating agent, extraction solvent and dispersive solvent, respectively. The experimental parameters related to the DLLME-SFO such as the type and volume of the extraction and dispersive solvent, extraction time, sample volume, the concentration of chelating agent and salt addition were investigated and optimized. Under the optimum conditions, the enrichment factor for copper was 122. The method was linear in the range from 0.5 to 300 ng mL −1 of copper in the samples with a correlation coefficient (r) of 0.9996 and a limit of detection of 0.1 ng mL −1 . The method was applied to the determination of copper in water and beverage samples. The recoveries for the spiked water and beverage samples at the copper concentration levels of 5.0 and 10.0 ng mL −1 were in the range between 92.0% and 108.0%. The relative standard deviations (RSD) varied from 3.0% to 5.6%.

Dispersive liquid-liquid microextraction for the spectrophotometric determination of Fe3+ with a water soluble Cu(II) phthalocyanine compound

“…To allow phase separation, it must be immiscible with water while miscible with disperser solvent. Besides, the extractive solvent must be denser than water [44][45][46]. For the proposed DLLME procedure, various organic solvents such as chloroform, carbon tetrachloride and dichloromethane were tested.…”

Methyl benzoate as a non-halogenated extraction solvent for dispersive liquid–liquid microextraction: Application to the preconcentration of copper(ii) with 1-nitroso-2-naphthol

“…[6][7][8][9][10] Recently, the use of non-halogenated extraction solvents has been attempted in DLLME. [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] In these cases, it is necessary to devise procedures for the separation of extraction solvents because their densities are usually smaller than that of water. When 1-undecanol [12][13][14][15][16] or 1-dodecanol 17,18 was used as the extraction solvent, the solvent was solidified in an ice bath after the extraction.…”

“…[6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] In these cases, it is necessary to devise procedures for the separation of extraction solvents because their densities are usually smaller than that of water. When 1-undecanol [12][13][14][15][16] or 1-dodecanol 17,18 was used as the extraction solvent, the solvent was solidified in an ice bath after the extraction. The formed solid was separated, and it was then dissolved with the appropriate organic solvent.…”