A Simple Pre-concentration Method for the Determination of Nickel(II) in Urine Samples Using UV-Vis Spectrophotometry and Flame Atomic Absorption Spectrometry Techniques

The cloud point technique was effectively utilized for extraction and pre-concentration of nickel(II) in urine samples before measurement by UV-Vis spectrophotometer and AAS techniques. The metal response to a para-aminophenol (PAP) reagent in a non-ionic surfactant Triton X-114 medium was to form the Ni-PAP complex. The adopted concentration for PAP, concentration of Triton X-114, pH effect and water bath temperature, incubation time, salt effect, and interference effects were all optimized. The calibration curve was linear over the range of (0.0625–1.25) mg L–1 with a correlation coefficient r2 of 0.9682 for the UV-Vis spectrophotometer at a λmax of 629 nm. The limit of detection was 0.005 mg/L. The relative standard deviation for six replicates was 1.07%. This method was applied successfully to determine copper (II) concentrations in 44 urine samples of occupational worker samples as determined by UV-Vis spectrophotometry and FAAS techniques.

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Optimization of cloud point extraction procedure with response surface methodology for quantification of iron by means of flame atomic absorption spectrometry

Journal of the Serbian Chemical Society ◽

10.2298/jsc120103055m ◽

2013 ◽

Vol 78 (1) ◽

pp. 115-127 ◽

Cited By ~ 2

Author(s):

Hossein Abdolmohammad-Zadeh ◽

Abdolhossein Naseri ◽

Golamhossein Sadeghi

Keyword(s):

Atomic Absorption Spectrometry ◽

Atomic Absorption ◽

Cloud Point ◽

Flame Atomic Absorption Spectrometry ◽

Cloud Point Extraction ◽

Limit Of Detection ◽

Absorption Spectrometry ◽

Ionic Surfactant ◽

Flame Atomic Absorption ◽

Relative Standard

A simple micelle-mediated phase separation method has been developed for the pre-concentration of trace levels of iron as a prior step to determination by flame atomic absorption spectrometry (FAAS). The method is based on the cloud point extraction (CPE) of iron using non-ionic surfactant polyethyleneglycolmono-p-nonylphenylether (PONPE 7.5) without adding any chelating agent. Several variables affecting the extraction efficiency were studied and optimized utilizing central composite design (CCD) and three levels full factorial design. Under the optimum conditions, the limit of detection (LOD), limit of quantification (LOQ) and pre-concentration factor were 1.5 ?g L-1, 5.0 ?g L-1 and 100, respectively. The relative standard deviation (RSD) for six replicate determinations at 50 ?g L?1 Fe(III) level was 1.97%. The calibration graph was linear in the rage of 5-100 ?g L-1, with a correlation coefficient of 0.9921. The developed method was validated by the analysis of two certified reference materials and applied successfully to the determination of trace amounts of Fe(III) in water and rice samples.

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Determination of cobalt in water samples by atomic absorption spectrometry after pre-concentration with a simple ionic liquid-based dispersive liquid-liquid micro-extraction methodology

Open Chemistry ◽

10.2478/s11532-010-0030-2 ◽

2010 ◽

Vol 8 (3) ◽

pp. 617-625 ◽

Cited By ~ 18

Author(s):

Hossein Abdolmohammad-Zadeh ◽

Elnaz Ebrahimzadeh

Keyword(s):

Ionic Liquid ◽

Atomic Absorption Spectrometry ◽

Atomic Absorption ◽

Water Samples ◽

Limit Of Detection ◽

Absorption Spectrometry ◽

Experimental Conditions ◽

Flame Atomic Absorption ◽

Relative Standard

AbstractA rapid dispersive liquid-liquid micro-extraction (DLLME) methodology based on the application of 1-hexylpyridinium hexafluorophosphate [C6py][PF6] ionic liquid (IL) as an extractant solvent was applied for the pre-concentration of trace levels of cobalt prior to determination by flame atomic absorption spectrometry (FAAS). 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was employed as a chelator forming a Co-PMBP complex to extract cobalt ions from aqueous solution into the fine droplets of [C6py][PF6]. Some effective factors that influence the micro-extraction efficiency include the pH, the PMBP concentration, the amount of ionic liquid, the ionic strength, the temperature and the centrifugation time which were investigated and optimized. In the optimum experimental conditions, the limit of detection (3s) and the enrichment factor were 0.70 µg L−1 and 60, respectively. The relative standard deviation (RSD) for six replicate determinations of 50 µg L−1 Co was 2.36%. The calibration graph using the pre-concentration system was linear at levels 2–166 µg L−1 with a correlation coefficient of 0.9982. The applicability of the proposed method was evaluated by the determination of trace amounts of cobalt in several water samples.

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Cloud point extraction and preconcentration of gold in geological matrices prior to flame atomic absorption determination

Open Chemistry ◽

10.2478/s11532-009-0093-0 ◽

2010 ◽

Vol 8 (1) ◽

pp. 34-40 ◽

Cited By ~ 14

Author(s):

Wifky El-Naggar ◽

Taysseer Lasheen ◽

El-Said Nouh ◽

Ahmed Ghonaim

Keyword(s):

Atomic Absorption ◽

Cloud Point ◽

Cloud Point Extraction ◽

Limit Of Detection ◽

Absorption Spectrometry ◽

Complexing Agent ◽

Rich Phase ◽

Flame Atomic Absorption ◽

Initial Aqueous Solution ◽

Triton X

AbstractBrilliant green was used as a complexing agent in cloud point extraction (CPE) and applied for selective preconcentration of trace amounts of gold in geological matrices. The analyte in the initial aqueous solution was acidified with hydrochloric acid (0.1 M) and octylphenoxypolyethoxyethanol (Triton X-114) was added as a surfactant. After phase separation, based on the cloud point separation of the mixture, the surfactant rich phase was diluted with methanol and the analyte determined in the surfactant rich phase by flame atomic absorption spectrometry (FAAS). After optimization of the complexation and extraction conditions, a preconcentration factor of 31 was obtained for only 10 mL of sample. The analytical curve was linear in the range of 3–1000 ng mL−1 and the limit of detection was 1.5 ng mL−1. The proposed method was applied to the determination of gold in geological samples.

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Development of a Cloud-Point Extraction Method for Cobalt Determination in Natural Water Samples

Journal of Chemistry ◽

10.1155/2013/615175 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Mohammad Reza Jamali ◽

Mohammad Gholinezhad ◽

Saiedeh Balarostaghi ◽

Reyhaneh Rahnama ◽

Seyed Hojjat Allah Rahimi

Keyword(s):

Cloud Point ◽

Water Samples ◽

Cloud Point Extraction ◽

Limit Of Detection ◽

Cobalt Content ◽

Cobalt Ions ◽

Flame Atomic Absorption ◽

Relative Standard ◽

Separation And Preconcentration ◽

Triton X

A new, simple, and versatile cloud-point extraction (CPE) methodology has been developed for the separation and preconcentration of cobalt. The cobalt ions in the initial aqueous solution were complexed with 4-Benzylpiperidinedithiocarbamate, and Triton X-114 was added as surfactant. Dilution of the surfactant-rich phase with acidified ethanol was performed after phase separation, and the cobalt content was measured by flame atomic absorption spectrometry. The main factors affecting CPE procedure, such as pH, concentration of ligand, amount of Triton X-114, equilibrium temperature, and incubation time were investigated and optimized. Under the optimal conditions, the limit of detection (LOD) for cobalt was 0.5 μg L-1, with sensitivity enhancement factor (EF) of 67. Calibration curve was linear in the range of 2–150 μg L-1, and relative standard deviation was 3.2% (c=100 μg L-1;n=10). The proposed method was applied to the determination of trace cobalt in real water samples with satisfactory analytical results.

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Cloud Point Extraction and Flame Atomic Absorption Spectrometry Determination of Lead (II) in Environmental and Food Samples

Journal of AOAC International ◽

10.5740/jaoacint.10-370 ◽

2012 ◽

Vol 95 (6) ◽

pp. 1797-1802 ◽

Cited By ~ 26

Author(s):

Mustafa Soylak ◽

Erkan Yilmaz ◽

Mehrorang Ghaedi ◽

Mortaza Montazerozohori ◽

Marjan Sheibani

Keyword(s):

Atomic Absorption Spectrometry ◽

Atomic Absorption ◽

Cloud Point ◽

Flame Atomic Absorption Spectrometry ◽

Cloud Point Extraction ◽

Extraction Procedure ◽

Absorption Spectrometry ◽

Bath Temperature ◽

Flame Atomic Absorption ◽

Triton X

Abstract A cloud point extraction procedure for the preconcentration of Pb2+ in various samples following complexation with 2,2-(1E,1′E)-1,1′-(2,2′-azanediylbis(ethane-2,1-diyl)bis(azan-1-yl-1-ylidene)) bis(ethan-1-yl-1-ylidene)diphenol in Triton X-114 after centrifugation is reported. A 0.5 mL portion of methanol acidified with 1.0 M HNO3 was added to the surfactant-rich phase prior to analysis by flame atomic absorption spectrometry. The influence of analytical parameters—including pH, concentrations of ligand, Triton X-114, and HNO3, bath temperature, heating time, and centrifugation rate and time—were optimized, and the effect of the matrix ions on the recovery of Pb2+ was investigated. An LOD of 1.9 ng/mL along with a preconcentration factor of 50 with RSD of 1.0% for Pb2+ were achieved. The proposed procedure was applied to the analysis of various real samples.

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Film Carbon Veil-Based Electrode Modified with Triton X-100 for Nitrite Determination

Chemosensors ◽

10.3390/chemosensors8030078 ◽

2020 ◽

Vol 8 (3) ◽

pp. 78

Author(s):

Natalia Yu. Stozhko ◽

Maria A. Bukharinova ◽

Ekaterina I. Khamzina ◽

Aleksey V. Tarasov ◽

Sergey V. Sokolkov

Keyword(s):

High Selectivity ◽

Limit Of Detection ◽

Ionic Surfactant ◽

Optimal Conditions ◽

Nitrite Determination ◽

Real Samples ◽

Relative Standard ◽

Triton X ◽

Higher Sensitivity ◽

Scanning Electron

A film carbon veil-based electrode (FCVE) modified with non-ionic surfactant Triton X-100 (TrX100) has been developed for nitrite determination. A new simple and producible technique of hot lamination (heat sealing) has been used for the FCVE manufacturing. The paper presents the findings of investigating the FCVE and the TrX100/FCVE by using voltammetry, chronoamperometry, and scanning electron microscopy. Modification of the electrode with TrX100 improves the hydrophilic property of its surface, which results in a larger electrode active area and higher sensitivity. Optimal conditions for nitrite determination with the use of the TrX100/FCVE have been identified. The linear range (LR) and the limit of detection (LOD) are 0.1–100 μM and 0.01 μM, respectively. The relative standard deviation (RSD) does not exceed 2.3%. High selectivity of the sensor ensures its successful application for the analysis of real samples (sausage products and natural water). The obtained results accord well with the results of the standard spectrophotometric method.

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Study on the determination of heavy metals in water samples with ultrasound-assisted dispersive liquid–liquid microextraction prior to FAAS

Water Science & Technology ◽

10.2166/wst.2012.524 ◽

2013 ◽

Vol 67 (2) ◽

pp. 247-253 ◽

Cited By ~ 7

Author(s):

Zonghao Li ◽

Gong Yu ◽

Jun Song ◽

Qi Wang ◽

Mousheng Liu ◽

...

Keyword(s):

Water Samples ◽

Absorption Spectrometry ◽

Influential Factors ◽

Ionic Surfactant ◽

Extraction Solvent ◽

Flame Atomic Absorption ◽

Relative Standard ◽

Dispersive Liquid Liquid Microextraction ◽

Liquid Microextraction

A new, simple and rapid method based on dispersive liquid–liquid microextraction (DLLME) was developed for extracting and preconcentrating copper (Cu), nickel (Ni), lead (Pb) and cadmium (Cd) in water samples prior to flame atomic absorption spectrometry (FAAS) analysis. 1-(2-thiazolylazo)-naphthol (TAN) was used as chelating reagents, and non-ionic surfactant Triton X-114 and CCl4 as disperser solvent and extraction solvent, respectively. Some influential factors relevant to DLLME, such as the concentration of TAN, type and volume of disperser and extraction solvent, pH and ultrasound time, were optimized. Under the optimal conditions, the calibration curve was linear in the range of 10–800 μg L−1 for Cu and Ni, 10–500 μg L−1 for Pb, and 10–1,000 μg L−1 for Cd, respectively. The limits of detection for the four metal ions were below 0.5 μg L−1, with the enhancement factors of 105, 66, 28 and 106 for Cu, Ni, Pb and Cd, respectively. The relative standard deviations (RSD, n = 6) were 2.6–4.1%. The proposed method was applied to determination of Cu, Ni, Pb and Cd in water samples and satisfactory relative recoveries (93.0–101.2%) were achieved.

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Mathematical equation correction to spectral and transport interferences in high-resolution continuum source flame atomic absorption spectrometry: determination of lead in phosphoric acid

Eclética Química ◽

10.1590/s0100-46702010000100002 ◽

2010 ◽

Vol 35 (1) ◽

pp. 19-24 ◽

Cited By ~ 1

Author(s):

Jorge Luiz Raposo Jr ◽

Silvana Ruella de Oliveira ◽

Joaquim Araújo Nóbrega ◽

José Anchieta Gomes Neto

Keyword(s):

Phosphoric Acid ◽

Limit Of Detection ◽

Absorption Spectrometry ◽

Mathematical Equation ◽

Continuum Source ◽

Relative Contribution ◽

Flame Atomic Absorption ◽

Calibration Curves ◽

Relative Standard ◽

Better Than

In this work, a new mathematical equation correction approach for overcoming spectral and transport interferences was proposed. The proposal was applied to eliminate spectral interference caused by PO molecules at the 217.0005 nm Pb line, and the transport interference caused by variations in phosphoric acid concentrations. Correction may be necessary at 217.0005 nm to account for the contribution of PO, since Atotal217.0005 nm = A Pb217.0005 nm + A PO217.0005 nm. This may be easily done by measuring other PO wavelengths (e.g. 217.0458 nm) and calculating the relative contribution of PO absorbance (A PO) to the total absorbance (Atotal) at 217.0005 nm: A Pb217.0005 nm = Atotal217.0005 nm - A PO217.0005 nm = Atotal217.0005 nm - k (A PO217.0458 nm). The correction factor k is calculated from slopes of calibration curves built up for phosphorous (P) standard solutions measured at 217.0005 and 217.0458 nm, i.e. k = (slope217.0005 nm/slope217.0458 nm). For wavelength integrated absorbance of 3 pixels, sample aspiration rate of 5.0 ml min-1, analytical curves in the 0.1 - 1.0 mg L-1 Pb range with linearity better than 0.9990 were consistently obtained. Calibration curves for P at 217.0005 and 217.0458 nm with linearity better than 0.998 were obtained. Relative standard deviations (RSD) of measurements (n = 12) in the range of 1.4 - 4.3% and 2.0 - 6.0% without and with mathematical equation correction approach were obtained respectively. The limit of detection calculated to analytical line at 217.0005 nm was 10 µg L-1 Pb. Recoveries for Pb spikes were in the 97.5 - 100% and 105 - 230% intervals with and without mathematical equation correction approach, respectively.

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Spectrophotometric Determination of Zirconium by Dispersive Liquid-Liquid Microextraction based on Solidification of Floating Organic Droplets

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22863 ◽

2020 ◽

Vol 32 (12) ◽

pp. 3191-3196

Author(s):

Intizam Ahmadov

Keyword(s):

Spectrophotometric Determination ◽

Limit Of Detection ◽

Ph Effect ◽

Ionic Surfactant ◽

Ligand Effect ◽

Limit Of Quantification ◽

Relative Standard ◽

Dispersive Liquid Liquid Microextraction ◽

Liquid Microextraction

In this study, a new method was developed for the spectrophotometric determination of zirconium by the procedure of dispersive liquid-liquid microextraction based on the solidification of floating organic droplets (DLLME-SFO). o-Nitrobenzene-azopyrocatechol (o-NBAP) and non-ionic surfactant (OP-10) were used in the complex formation. At the first stage, a separation and solidification processes were carried out, after which the solidified samples were examined by spectrophotometric method. The effect of various parameters viz. pH effect, ion resistance, ligand effect, volume and type of extraction and dispersion solution, extraction time and temperature effect were studied. The results of the experiment were optimized with design programs. The calibration curve was linear ranging from 0.5 to70 μg L-1, with a correlation coefficient of 0.998. The limit of detection (LOD) is 0.12 μg L-1, the limit of quantification (LOQ) is 0.40 μg L-1 and the relative standard deviation (RSD) at 60 μg L-1 is 1.6% (n=6). This method was also applied to determine zirconium in various water samples. The obtained reextraction amount was 98-110%.

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Selective Ligandless Cloud Point Extraction of Palladium from Water and Dust Samples

Journal of AOAC International ◽

10.5740/jaoacint.12-305 ◽

2015 ◽

Vol 98 (1) ◽

pp. 201-205 ◽

Cited By ~ 3

Author(s):

Sayed Zia Mohammadi ◽

Mohsen Mohammadnezhad

Keyword(s):

Cloud Point ◽

High Efficiency ◽

Cloud Point Extraction ◽

Absorption Spectrometry ◽

Ionic Surfactant ◽

Solution Ph ◽

Flame Atomic Absorption ◽

Separation And Preconcentration ◽

Triton X

Abstract In this study, the phase-separation phenomenon ofnon-ionic surfactants was used for separation and preconcentration of Pd(II). The cloud point extraction(CPE) method is based on the formation of PdI2 which is then entrapped in the non-ionic surfactant Triton X-114. Ethanol acidified with 0.5 M HNO3 was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry. The main factors affecting CPE efficiency, such as sample solution pH, concentration of iodide ion and Triton X-114, equilibration temperature and time, were all investigated and optimized. At optimum conditions, a calibration curve was constructed for the determination of palladium according to the ligandless CPE procedure. Linearity was maintained between 1.0 to 500.0 ng/mL. The LOD based on three times the SD of the blank divided by the slope of analytical curve, (3Sb/m) was 0.3 ng/mL. Seven replicatedeterminations of a solution containing of 4.0 μg palladium gave a mean absorbance of 0.359 with RSD ±1.85%. The high efficiency of CPE to carry out the determination of palladium in complex matrixes was demonstrated. The proposed method has beenapplied to the determination of trace amounts of palladium in a platinum-iridium alloy, water, and dust samples, with satisfactory results.

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