A new method of microvolume back-extraction procedure for enrichment of Pb and Cd and determination by flame atomic absorption spectrometry

Carasek, Eduardo; Tonjes, Jussara Wick; Scharf, Mauro

doi:10.1016/s0039-9140(01)00556-2

Cited by 72 publications

(30 citation statements)

References 24 publications

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“…A comparison of the current method with the other reported methods [16][17][18][19] is shown in Table 3. The results showed that, the enrichment factor and the detection limit obtained by the proposed method are comparable to methods reported in the literature.…”

Section: Comparison Of Ll-dllme Procedures With the Other Reported Metmentioning

confidence: 99%

Combination of flame atomic absorption spectrometry with ligandless-dispersive liquid- liquid microextraction for preconcentration and determination of trace amount of lead in water samples

Mohammadi¹,

Shamspur²,

Baghelani³

2013

Bull. Chem. Soc. Eth.

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ABSTRACT.A new ligandless-dispersive liquid-liquid microextraction method has been developed for the separation and flame atomic absorption spectrometry determination of trace amount of lead(II) ion. In the proposed approach 1,2-dicholorobenzene and ethanol were used as extraction and dispersive solvents. Factors influencing the extraction efficiency of lead, including the extraction and dispersive solvent type and volume, pH of sample solution, concentration of chloride and extraction time were studied. Under the optimal conditions, the calibration curve was linear in the range of 7.0-6000 ng mL −1 of lead with R 2 = 0.9992 (n = 10) and detection limit based on three times the standard deviation of the blank (3Sb) was 0.5 ng mL −1 in original solution. The relative standard deviation for eight replicate determinations of 1.0 µg mL -1 lead was ±1.6%. The high efficiency of dispersive liquid-liquid microextraction to carry out the determination of trace amounts of lead in complex matrices was demonstrated. The proposed method has been applied for determination of trace amounts of lead in water samples and satisfactory results were obtained. The accuracy was checked by analyzing a certified reference material from the National Institute of Standard and Technology, Trace elements in water (NIST CRM 1643e).

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Section: Comparison Of Ll-dllme Procedures With the Other Reported Metmentioning

confidence: 99%

Combination of flame atomic absorption spectrometry with ligandless-dispersive liquid- liquid microextraction for preconcentration and determination of trace amount of lead in water samples

Mohammadi¹,

Shamspur²,

Baghelani³

2013

Bull. Chem. Soc. Eth.

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“…To assure the homogeneity and statistical validity of the method, a paired t-test was applied to the group of results; the determined "t" value was 0.187, which is below the reference t-value for a 95% confidence interval (t = 2.78). Table 6 indicates the limit of detection (LOD), the relative standard deviation, the sample preparation time and the sample volume in the LLE-microvolume back-extraction [31], co-precipitation [32], off-line SPE (Solid Phase Extraction) [33], on-line SPE [34] CPE and (Cloud Point Extraction) [35] for the extraction and determination of lead in water samples. The comparison of the results exhibits that LOD and the enrichment factor (or enhancement factor) in the present method were better than those of the other methods.…”

Section: Applicationmentioning

confidence: 99%

Determination of Trace Amounts of Lead by Modified Graphite Furnace Atomic Absorption Spectrometry after Liquid Phase Microextraction with Pyrimidine-2-thiol

Nazari¹

2011

AJAC

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The liquid phase microextraction (LPME) was combined with the modified Graphite furnace atomic absorption spectrometry (GF-AAS) for determination of lead in the water and solid samples. In a preconcentration step, lead was extracted from a 2 ml of its aqueous sample in the pH = 5 as lead-Pyrimidine-2-thiol cationic complex into a 4 µl drop of 1,2 dichloroethane and ammonium tetraphenylborate as counter ion immersed in the solution. In the drop, the lead-Pyrimidine-2-thiol ammonium tetraphenylborate ion associated complex was formed. After extraction, the microdrop was retracted and directly transferred into a graphite tube modified by [W.Pd.Mg] (c). Some effective parameters on extraction and complex formation, such as type and volume of organic solvent, pH, concentration of chelating agent and counter ion, extraction time, stirring rate and effect of salt were optimized. Under the optimum conditions, the enrichment factor and recovery were 525% and 94%, respectively. The calibration graph was linear in the range of 0.01 -12 µg·L -1 with correlation coefficient of 0.9975 under the optimum conditions of the recommended procedure. The detection limit based on the 3S b criterion was 0.0072 µg·L -1 and relative standard deviation (RSD) for ten replicate measurement of 0.1 µg·L -1 and 0.4 µg·L -1 lead was 4.5% and 3.8% respectively. The characteristic concentration was 0.0065 µg·L -1 equivalent to a characteristic mass of 26 fg. The results for determination of lead in reference materials, spiked tap water and seawater demonstrated the accuracy, recovery and applicability of the presented method.

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“…Although the development of modern analytical instruments provides a great enhancement in analysis, in many cases the available analytical instrumentation does not demonstrate enough sensitivity for the analysis of natural samples. 15 Nevertheless, the detection of metal trace elements in aqueous samples is difficult due to various factors, particularly their low concentration and the matrix effects. 16 Several methods have been reported for the separation and preconcentration of metal ions, such as coprecipitation, 17,18 liquid-liquid extraction (LLE), 19,20 solid-phase extraction (SPE), [21][22][23] and cloud point extraction (CPE).…”

Section: Introductionmentioning

confidence: 99%

Decanoic Acid Reverse Micelle-Based Coacervates for Microextraction of Silver in Natural Waters Prior to Flame Atomic Absorption Spectrometry Determination

Shokouhifar¹,

Hosseini²,

Jamali³

et al. 2016

Journal of the Brazilian Chemical Society

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In the present work, a novel, simple, and efficient method for the determination of silver in natural water samples was developed. The method is based on the extraction of silver with coacervate made up of decanoic acid reverse micelles and the subsequent determination by flame atomic absorption spectrometry (FAAS). Dithizone was used as a chelating agent. To obtain the best extraction results, some experimental parameters (such as coacervate composition, pH, concentration of chelating agent, and ionic strength) affecting the extraction efficiency were investigated and optimized. Under optimum conditions, the calibration curve was linear in the concentration range of 5-200 µg L -1 , with the correlation coefficient (r) equal to 0.995. The limit of detection and the enrichment factor were 1.6 µg L -1 and 15, respectively. The method was successfully applied to the analysis of silver in natural water samples.

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A new method of microvolume back-extraction procedure for enrichment of Pb and Cd and determination by flame atomic absorption spectrometry

Cited by 72 publications

References 24 publications

Combination of flame atomic absorption spectrometry with ligandless-dispersive liquid- liquid microextraction for preconcentration and determination of trace amount of lead in water samples

Combination of flame atomic absorption spectrometry with ligandless-dispersive liquid- liquid microextraction for preconcentration and determination of trace amount of lead in water samples

Determination of Trace Amounts of Lead by Modified Graphite Furnace Atomic Absorption Spectrometry after Liquid Phase Microextraction with Pyrimidine-2-thiol

Decanoic Acid Reverse Micelle-Based Coacervates for Microextraction of Silver in Natural Waters Prior to Flame Atomic Absorption Spectrometry Determination

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