Search

A simple, efficient, green, and organic solventless dispersive liquid–liquid microextraction procedure was developed to determine Co(II) and Ni(II) ions in water and fruit juice samples by flame atomic absorption spectrometry. In this study, for the first time, both of dispersive and extraction solvents of the method are deep eutectic solvents. Therefore, it is performed without using any organic solvent. The dispersive solvent is composed of choline chloride and butyric acid at a molar ratio of 1:2. The solvent prepared from a mixture of choline chloride and phenylacetic acid at a molar ratio of 1:2 is acted as an extraction solvent. Effect of various analytical parameters such as constituents and molar ratios of dispersive and extraction solvents, volume of the synthesized solvents, temperature, ionic strength, and pH of sample solution on extraction efficiency of the method were investigated and optimized. After optimization of the method, good linearity in the ranges of 0.29–40 μg L−1 and 0.5–40 μg L−1 with coefficients of determination of 0.9919 and 0.9976 was obtained for Co(II) and Ni(II), respectively. Low limits of detection were obtained for Co(II) and Ni(II) (0.10 and 0.17 μg L−1, respectively). The extraction recoveries of the analytes were 95.4% and 92.8% for Co(II) and Ni(II), respectively. To investigate validity of the method, SPS-WW2 as a certificate reference material was analyzed with the proposed method. Finally, the method was successfully applied to determine Co(II) and Ni(II) ions in different water and fruit juice samples. [ABSTRACT FROM AUTHOR]

This paper describes determination of lead in gasoline by graphite furnace atomic absorption spectrometry after application of an air-assisted liquid–liquid microextraction method using deep eutectic solvent. In this study, for the first time, a ternary deep eutectic solvent was synthesized from menthol, mandelic acid, and glycolic acid and was used as a complexing agent and an extraction solvent, simultaneously. Under optimized conditions, the proposed method made possible the determination of lead in the range of 5–50 ng L−1 with a good linearity. The obtained detection and quantification limits were 1.6 and 5.0 ng L−1, respectively. Moreover, enrichment factor and extraction recovery values were 166 and 91.3%, respectively. The optimized and developed method was successfully used for the determination of lead in various gasoline samples. [ABSTRACT FROM AUTHOR]

A vortex‐assisted dispersive micro‐solid‐phase extraction procedure using a new and green sorbent was developed as a simple, fast, and efficient sample preparation method for the extracting five pesticides in several fruit juice samples. In this study, for the first time, riboflavin was used as an efficient sorbent. A few milligrams of riboflavin was directly added into the aqueous solution containing the analytes to adsorb them. After adsorption the analytes, they were desorbed and more concentrated by a dispersive liquid–liquid microextraction procedure. The influence of several effective parameters such as amount of riboflavin, pH, vortex time, eluent nature and volume, and extraction solvent type and volume on the extraction efficiency was investigated. In optimal conditions, linear ranges of the calibration curves were broad. The limits of detection and quantification were attained in the ranges of 0.56–1.5 and 1.9–0.52 ng mL−1, respectively. The proposed method demonstrated to be suitable for concurrent extraction of the studied pesticides in various fruit juice samples with high enrichment factors (320–360) and precision (relative standard deviation ≤7.8% for intra‐ [n = 6] and interday [n = 4] precisions at a concentration of 25 ng mL−1 of each pesticide). [ABSTRACT FROM AUTHOR]

A green, simple, rapid, and efficient ligandless air-assisted liquid-liquid microextraction procedure based on solidification of a ternary deep eutectic solvent was developed for the extraction of trace amounts of cadmium(II) and zinc(II) ions in aqueous samples prior to their determination by flame atomic absorption spectrometry. For this purpose, the deep eutectic solvent is formed by mixing sorbitol, menthol, and mandelic acid at a suitable mole ratio and after heating for a short time, a deep eutectic solvent with low density compared to water is synthesised. The synthesised solvent is used as a chelating agent and also as an extraction solvent. Under the optimum experimental conditions, the linear ranges were obtained in the ranges of 0.5–12.5 and 0.5–10.0 µg L−1 for Zn(II) and Cd(II), respectively. The relative standard deviations (n = 6, C = 2.5 µg L−1 of each cation) were 4.2% and 3.4%, for Cd(II) and Zn(II), respectively. Moreover, the obtained detection limits were 0.15 and 0.12 µg L−1 for Cd(II) and Zn(II), respectively. The accuracy of the developed method was studied by analysing SPS-WW2 Batch 108 water as a certified reference material. Finally, the proposed method was successfully applied in the determination of Cd(II) and Zn(II) ions in water and fruit juice samples. Abbreviations: AALLME: Air-assisted liquid-liquid microextraction; ER: Extraction recovery; FAAS: Flame atomic absorption spectrometry; LOD: Limit of detection; LOQ: Limit of quantification; RSD: Relative standard deviation [ABSTRACT FROM AUTHOR]

Copyright of Oilseeds & Fats, Crops & Lipids (OCL) is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A green and efficient dispersive liquid-liquid microextraction method based on a new deep eutectic solvent has been developed for the preconcentration and extraction of cobalt and nickel ions. The deep eutectic solvent is formed by mixing choline chloride (hydrogen bond acceptor) and 4-aminophenol (hydrogen bond donor). Then, it is used as a chelating agent as well as extraction solvent. Under the optimum experimental conditions, the linear ranges for Ni(II) and Co(II) were 0.80–50 and 0.50–50 µgL−1, respectively, by flame atomic absorption spectrometry. The obtained detection limits were 0.30 and 0.22 µg L−1 for Ni(II) and Co(II), respectively. ChCl: choline chloride; DES: deep eutectic solvent; DLLME: dispersive liquid-liquid microextraction; EF: enrichment factor; ER: extraction recovery; FAAS: flame atomic absorption spectrometry; LOD: limit of detection; LOQ: limit of quantification. [ABSTRACT FROM AUTHOR]

A new sample preparation method, cyclohexylamine-based heat-induced homogeneous liquid–liquid microextraction, has been developed for the extraction and preconcentration of Cd(II) and Zn(II) ions in edible oils followed by flame atomic absorption spectrometry determination. First, the analytes are extracted into an acidic solution (a balanced mixture of HNO3 and HCl). Second, they are preconcentrated via the microextraction method. Accordingly, cyclohexylamine (as a complexing agent and an extraction solvent) is added at µL-level into the obtained solution containing the analytes to form a homogeneous solution followed by the addition of sodium chloride. After manual shaking, the obtained solution is placed in a water bath thermostated at 60 °C. A cloudy solution because of the decrease in cyclohexylamine solubility in water at high temperature is formed. After centrifuging fine droplets of cyclohexylamine containing Cd(II) and Zn(II)—cyclohexylamine complexes are collected on the top of the aqueous phase. The preconcentrated analytes in the upper phase by use of flame atomic absorption spectrometry are analyzed and determined. Several variables possibly affecting the extraction efficiency were investigated and optimized. Under the optimum conditions, the calibration curves were linear in the ranges of 10–300 and 2.5–200 µg kg− 1 for Cd(II) and Zn(II), respectively. Repeatability of the proposed method, expressed as relative standard deviation, was obtained 2.4 and 1.7% for Cd (II) and Zn(II), respectively. Moreover, the detection limits of the selected analytes were obtained 3.8 and 0.6 µg kg− 1 for Cd(II) and Zn(II), respectively. [ABSTRACT FROM AUTHOR]

A green effervescence-assisted dispersive liquid-liquid microextraction based on phthalic acid as complexing agent and co-disperser performed in a narrow-bore tube has been developed for the extraction and preconcentration of zinc and cadmium from high volume of aqueous sample, followed by flame atomic absorption spectrometry. Initially phthalic acid is added to the aqueous sample to form phthalate-metal complexes. Then the sample is transferred by a syringe into a home-made setup consists of a narrow-bore glass tube with its nozzle-shaped head when its bottom connected to a glass balloon containing sodium bicarbonate and an extraction solvent at μL-level. Immediately a reaction occurs between the sodium bicarbonate and the excess amount of phthalic acid, and the produced CO 2 leads to the dispersion of the extractant into the sample as fine droplets which result in extraction of the complexes into the extractant. Under the optimum conditions, the calibration curves were linear in the ranges of 0.50–7.5 and 0.30–7.5 μg L−1 for cadmium and zinc, respectively. The detection limits were 0.21 and 0.14 μg L−1 for cadmium and zinc, respectively. Extraction recoveries were 89% and 100%, and enrichment factors were found to be 117 and 131, for cadmium and zinc, respectively. Finally environmental water and fruit juice samples were successfully analyzed using the developed method. • A green effervescence-assisted DLLME based on phthalic acid performed in a narrow-bore tube has been developed. • For the first time, phthalic acid was simultaneously used for complexing of analytes and as co-disperser in DLLME. • DLLME was performed without addition of toxic complexing agent and disperser solvent. • Much low of an organic solvent was used as the extraction solvent in the absence of disperser solvent, for high volume (25 mL) of sample. • The linearity, ER, EF, and repeatability of the method were validated within the acceptable ranges. [ABSTRACT FROM AUTHOR]

A simple, green, rapid, and efficient ligandless dispersive liquid-liquid microextraction procedure based on solidification of a ternary deep eutectic solvent has been proposed for the extraction of trace amounts of Cd(II), Cu(II), and Pb(II) ions in milk samples prior to their determination by flame atomic absorption spectrometry. Initially, a suitable mole ratio of sorbitol, menthol, and mandelic acid are mixed in a test tube, and after heating, a deep eutectic solvent with low density compared to water is formed. The synthesized solvent is used as a chelating agent and an extraction solvent in the extraction of some heavy metal ions from milk samples. The influence of several effective parameters on the responses and extraction recoveries of the analytes was investigated. Under the optimum experimental conditions, the linear ranges were in the ranges of 1.0–40 μg L−1 for Cd(II) and Pb(II), and 1.0–25 μg L−1 for Cu(II). The obtained relative standard deviations (n = 6, C = 2.5 μg L−1 of each cation) and detection limits were in the ranges of 3.4–4.1% and 0.38–0.42 μg L−1, respectively. Finally, the developed method was successfully applied for the determination of Cd(II), Cu(II), and Pb(II) ions in different milk samples. Image 1 • An efficient ligandless DLLME method using a synthesized ternary DES is proposed for the extraction and preconcentration of Cd(II), Cu(II), and Pb(II) ions at trace levels from milk samples. • A few microliters of the synthesized DES was used simultaneously as a complexing agent and an extraction solvent, therefore, the extraction was performed without using any organic solvent. • This study is the first report on the application of the present method for the extraction of heavy metals in milk samples. • The proposed method offers numerous advantages, such as simplicity, ease of operation, and low cost. • The developed method was used for the determination of the analytes in different milk samples. [ABSTRACT FROM AUTHOR]

In this study, a simple and sensitive analytical method was developed for the determination of some heavy metal ions in aqueous samples using inductively coupled plasma-optical emission spectrometry. In this method, firstly, cobalt ferrite nanoparticles were synthesized before they were functionalized with a deep eutectic solvent. The used functionalization solvent was prepared by mixing choline chloride and p -aminophenol. The obtained new nanoadsorbent was used for the extraction of Zn(II), Ni(II), Cu(II), Pb(II), and Hg(II) from the sample solutions by dispersive micro solid phase extraction. The effect of some important parameters such as the sorbent amount, ionic strength, pH, agitation mode and time, and elution solvent type and volume on the extraction efficiency of the method was investigated. Broad linear ranges (1.83–200 ng mL−1) with low limits of detection in the range of 0.54–1.3 ng mL−1 were obtained. The accuracy of the developed method was investigated by determination of the analytes in a certified reference material (SPS-WW2 Batch 108 water). The extraction recoveries of the analytes were obtained in the range of 72–90%. Finally, the developed method was successfully applied to determine the selected ions in different water and fruit juice samples, and the relative recoveries were obtained in the range of 85–104%. • Cobalt ferrite nanoparticles were functionalized with a deep eutectic solvent. • A green solvent instead of toxic and expensive reagents was used for modification. • The sorbent was used for the extraction of Zn, Ni, Cu, Pb, and Hg. • Using low amount of sorbent and low LODs were important features of the method. [ABSTRACT FROM AUTHOR]