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

2010 ◽  
Vol 35 (1) ◽  
pp. 19-24 ◽  
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.

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

2018 ◽  
Vol 35 (1) ◽  
pp. 19
Author(s):  
Jorge Luiz Raposo Junior ◽  
Silvana Ruella De Oliveira ◽  
Joaquim Araújo Nóbrega ◽  
José Gomes Anchieta 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 Atotal 217.0005 nm = A Pb 217.0005 nm + A PO 217.0005 nm. This may be easily done by measuring other PO wavelengths (e.g. 217.0458 nm) and calculating the relative contribution of PO absorbance (APO) to the total absorbance (Atotal) at 217.0005 nm: A Pb 217.0005 nm = Atotal 217.0005 nm - A PO 217.0005 nm = Atotal 217.0005 nm - k (A PO 217.0458 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.

scholarly journals 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

2010 ◽  
Vol 8 (3) ◽  
pp. 617-625 ◽  
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.

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

2019 ◽  
Vol 19 (3) ◽  
pp. 638 ◽  
Author(s):  
Ahmed Fadhil Khudhair ◽  
Mouyed Khudhair Hassan ◽  
Hasan F. Alesary ◽  
Ahmed S. Abbas
Keyword(s):  
Limit Of Detection ◽  
Ph Effect ◽  
Absorption Spectrometry ◽  
Bath Temperature ◽  
Urine Samples ◽  
Ionic Surfactant ◽  
Concentration Method ◽  
Flame Atomic Absorption ◽  
Relative Standard ◽  
Triton X

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.

scholarly journals DETERMINATION OF COPPER AT WIDE RANGE CONCENTRATIONS USING INSTRUMENTAL FEATURES OF HIGH-RESOLUTION CONTINUUM SOURCE FLAME ATOMIC ABSORPTION SPECTROMETRY

2018 ◽  
Vol 35 (4) ◽  
pp. 87
Author(s):  
Renata Toledo Lima ◽  
Jorge Luiz Raposo Júnior ◽  
Alex Virgílio ◽  
José Anchieta Gomes Neto
Keyword(s):  
High Resolution ◽  
Atomic Absorption Spectrometry ◽  
Atomic Absorption ◽  
Flame Atomic Absorption Spectrometry ◽  
Absorption Spectrometry ◽  
Continuum Source ◽  
Flame Atomic Absorption ◽  
Relative Standard ◽  
Wide Range

This work describes a method to determine Cu at wide range concentrations in a single run without need of further dilutions employing high-resolution continuum source flame atomic absorption spectrometry. Different atomic lines for Cu at 324.754 nm, 327.396 nm, 222.570 nm, 249.215 nm and 224.426 nm were evaluated and main figures of merit established. Absorbance measurements at 324.754 nm, 249.215 nm and 224.426 nm allows the determination of Cu in the 0.07 – 5.0 mg L-1, 5.0 – 100 mg L-1 and 100 – 800 mg L-1 concentration intervals respectively with linear correlation coefficients better than 0.998. Limits of detection were 21 μg L-1, 310 μg L-1 and 1400 μg L-1 for 324.754 nm, 249.215 nm and 224.426 nm, respectively and relative standard deviations (n = 12) were £ 2.7%. The proposed method was applied to water samples spiked with Cu and the results were in agreement at a 95% of confidence level (paired t-test) with those obtained by line-source flame atomic absorption spectrometry.

scholarly journals Determination of copper at wide range concentrations using instrumental features of high-resolution continuum source flame atomic absorption spectrometry

2010 ◽  
Vol 35 (4) ◽  
pp. 87-92 ◽  
Author(s):  
Renata Toledo Lima ◽  
Jorge Luiz Raposo Jr. ◽  
Alex Virgílio ◽  
José Anchieta Gomes Neto
Keyword(s):  
High Resolution ◽  
Atomic Absorption Spectrometry ◽  
Atomic Absorption ◽  
Flame Atomic Absorption Spectrometry ◽  
Absorption Spectrometry ◽  
Continuum Source ◽  
Flame Atomic Absorption ◽  
Relative Standard ◽  
Wide Range

This work describes a method to determine Cu at wide range concentrations in a single run without need of further dilutions employing high-resolution continuum source flame atomic absorption spectrometry. Different atomic lines for Cu at 324.754 nm, 327.396 nm, 222.570 nm, 249.215 nm and 224.426 nm were evaluated and main figures of merit established. Absorbance measurements at 324.754 nm, 249.215 nm and 224.426 nm allows the determination of Cu in the 0.07 - 5.0 mg L-1, 5.0 - 100 mg L-1 and 100 - 800 mg L-1 concentration intervals respectively with linear correlation coefficients better than 0.998. Limits of detection were 21 µg L-1, 310 µg L-1 and 1400 µg L-1 for 324.754 nm, 249.215 nm and 224.426 nm, respectively and relative standard deviations (n = 12) were £ 2.7%. The proposed method was applied to water samples spiked with Cu and the results were in agreement at a 95% of confidence level (paired t-test) with those obtained by line-source flame atomic absorption spectrometry.

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

2013 ◽  
Vol 78 (1) ◽  
pp. 115-127 ◽  
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.

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

2010 ◽  
Vol 8 (1) ◽  
pp. 34-40 ◽  
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.

Modern Methodological Approaches to Sample Preparation for the Determination of Trace Elements in Food Products and Plant Raw Materials

2021 ◽  
pp. 48-54
Author(s):  
NE Fedorova ◽  
MV Egorova ◽  
AS Rodionov
Keyword(s):  
High Resolution ◽  
Sample Preparation ◽  
Atomic Absorption Spectrometry ◽  
Atomic Absorption ◽  
Flame Atomic Absorption Spectrometry ◽  
Limit Of Detection ◽  
Absorption Spectrometry ◽  
Flame Atomic Absorption ◽  
Homogeneity Of Variances ◽  
Limit Of Quantitation

Introduction. Various copper compounds are most widely used as plant protection agents in agriculture. From a hygienic point of view, information on excessive accumulation of copper in plants related to the use of a specific formulation of copper-containing pesticides is of interest. Our objective was to assess feasibility of increasing statistical significance of results of determining low residue levels of a copper-containing pesticide in apple samples by flame atomic absorption spectrometry using a high-resolution spectrometer in combination with developed approaches to sample preparation of plant-based foods, including homogenization with dry ice and microwave mineralization. Materials and methods: We analyzed 30 samples of apples collected in three different agro-climatic zones by flame atomic absorption spectrometry and electrothermal atomization atomic absorption spectrometry. Both methods were validated on 10 samples with added copper at levels 1-5 of the lower limit of quantitation. A statistical calculation was performed based on a simple Student’s test to assess the significance of differences between the results of measurements by flame and electrothermal techniques. Homogeneity of variances was estimated using the Fisher test to clarify the possibility of comparing two data sets. Results: The use of a technique of cryo-grinding and microwave decomposition in a microwave reactor in combination with a high-resolution continuum source atomic absorption spectrometry demonstrated a decrease in scattering and the limit of detection and better repeatability in the analysis of parallel samples. Results of statistical calculations confirmed the homogeneity of variances in data samples obtained for electrothermal and flame techniques, and the further Student’s t-test showed insignificant differences between the results of measurements obtained by FAAS and ET-AAS. Conclusion: Our findings prove that modern methods of sample preparation in combination with highly sensitive equipment allow a significant reduction in the limit of detection and scattering of test results.

Sign in / Sign up

Export Citation Format

Share Document