WorldWideScience

Sample records for atomic absorption determination

  1. Spectrofluorimetric, Atomic Absorption Spectrometric and Spectrophotometric Determination of Some Fluoroquinolones

    Directory of Open Access Journals (Sweden)

    Hesham Salem

    2005-01-01

    Full Text Available Simple, accurate, sensitive and selective spectrofluorimetric, atomic absorption spectrometric and spectrophotometric methods are described for the quantitative determination of ten fluoroquinolones (amifloxacin, ciprofloxacin hydrochloride, difloxacin hydrochloride, enoxacin, enrofloxacin, lomefloxacin hydrochloride, levofloxacin, norfloxacin, ofloxacin and pefloxacin mesylate. The first method was a spectrofluorimetric method in which samples of the studied drugs in 0.1 N H2SO4 showed native fluorescence at 450 nm when excitation was at 290 nm. The calibration graph was rectilinear from 0.3-1.4 μg mL-1 (method I. Cobalt sulphate was used for precipitation of the ion associates formed from the reaction with the cited drugs. The formation and solubility of the solid complexes at the optimum conditions of pH and ionic strength values have been studied. The method depends on direct determination of the ions in the precipitate or indirect determination of the ions in the filtrate by atomic absorption spectroscopy. The optimum conditions for precipitation were carefully studied. Rectilinear calibration graphs were obtained in the range of 3-30 μg mL-1 for each of the investigated drugs. The molar ratios of the formed chelats were determined by Job's method and their association constants were also calculated (method II. Ammonium vanadate was used for the spectrophotometric determination of the selected fluoroquinolones by oxidation in sulphuric acid medium resulting in the development of a greenish blue colour measured at 766 nm which was attributed to the vanadium (IV produced by reduction of vanadium (V by the selected drugs. The optimum conditions for heating time, reagent concentration and sulphuric acid concentration were carefully studied. The accuracy and precision of the proposed method was confirmed by estimating five or six replicates within Beer's law limits were obtained in the range 10-40 μg mL-1 for each of the investigated drugs

  2. Cinchocaine hydrochloride determination by atomic absorption spectrometry and spectrophotometry.

    Science.gov (United States)

    Abdel-Ghani, Nour T; Youssef, Ahmed F A; Awady, Mohamed A

    2005-05-01

    Two sensitive spectrophotometric and atomic absorption spectrometric procedures have been developed for determination of cinchocaine hydrochloride (Cin.Cl) in pure form and in pharmaceutical formulation. The spectrophotometric method was based on formation of an insoluble colored ion-associate between the cited drug and tetrathiocyanatocobaltate (CoTC) or hexathiocyanatochromate (CrTC) which dissolved and extracted in an organic solvent. The optimal experimental conditions for quantitative extraction such as pH, concentration of the reagents and solvent were studied. Toluene and iso-butyl alcohol proved to be the most suitable solvents for quantitative extraction of Cin-CoTC and Cin-CrTC ion-associates with maximum absorbance at 620 and 555 nm, respectively. The optimum concentration ranges, molar absorptivities, Ringbom ranges and Sandell sensitivities were also evaluated. The atomic absorption spectrometric method is based on measuring of the excess cobalt or chromium in the aqueous solution, after precipitation of the drug, at 240.7 and 357.9 nm, respectively. Linear application ranges, characteristic masses and detection limits were 57.99-361.9, 50.40 and 4.22 microg ml(-1) of Cin.Cl, in case of CoTC, while 37.99-379.9, 18.94 and 0.81 microg ml(-1) in case of CrTC.

  3. The determination of vanadium in brines by atomic absorption spectroscopy

    Science.gov (United States)

    Crump-Wiesner, Hans J.; Feltz, H.R.; Purdy, W.C.

    1971-01-01

    A standard addition method is described for the determination of vanadium in brines by atomic absorption spectroscopy with a nitrous oxide-acetylene flame. Sample pH is adjusted to 1.0 with concentrated hydrochloric acid and the vanadium is directly extracted with 5% cupferron in methyl isobutyl ketone (MIBK). The ketone layer is then aspirated into the flame and the recorded absorption values are plotted as a function of the concentration of the added metal. As little as 2.5 ??g l-1 of vanadium can be detected under the conditions of the procedure. Tungsten and tin interfere when present in excess of 5 and 10 ??g ml-1, respectively. The concentrations of the two interfering ions normally found in brines are well below interference levels. ?? 1971.

  4. Ultratrace determination of tin by hydride generation in-atomizer trapping atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Průša, Libor [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic); Charles University in Prague, Faculty of Science, Department of Analytical Chemistry, Hlavova 8, Prague 2, CZ 128 43 Czech Republic (Czech Republic); Dědina, Jiří [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic); Kratzer, Jan, E-mail: jkratzer@biomed.cas.cz [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic)

    2013-12-04

    Graphical abstract: -- Highlights: •In-atomizer trapping HG-AAS was optimized for Sn. •A compact quartz trap-and-atomizer device was employed. •Generation, preconcentration and atomization steps were investigated in detail. •Hundred percent preconcentration efficiency for tin was reached. •Routine analytical method was developed for Sn determination (LOD of 0.03 ng mL{sup −1} Sn). -- Abstract: A quartz multiatomizer with its inlet arm modified to serve as a trap (trap-and-atomizer device) was employed to trap tin hydride and subsequently to volatilize collected analyte species with atomic absorption spectrometric detection. Generation, atomization and preconcentration conditions were optimized and analytical figures of merit of both on-line atomization as well as preconcentration modes were quantified. Preconcentration efficiency of 95 ± 5% was found. The detection limits reached were 0.029 and 0.14 ng mL{sup −1} Sn, respectively, for 120 s preconcentration period and on-line atomization mode without any preconcentration. The interference extent of other hydride forming elements (As, Se, Sb and Bi) on tin determination was found negligible in both modes of operation. The applicability of the developed preconcentration method was verified by Sn determination in a certified reference material as well as by analysis of real samples.

  5. Atomic Absorption Spectrophotometric Determination of Lead in White Rice

    Directory of Open Access Journals (Sweden)

    Sherryl M. Montalbo

    2015-11-01

    Full Text Available Recent studies on the heavy metal content of rice from various parts of the world have alarmed rice-eating nations, including the Philippines. In 2013, Philippine Rice Research Institute (PhilRice reported that rice in the Philippines needs to be evaluated to determine whether these contain heavy metals such as lead. This research aimed to assess the presence of lead in the three highest selling rice varieties harvested in Oriental Mindoro and sold in Batangas City public markets. It was done to asses if the lead concentration in the raw and cooked rice samples conform to the maximum acceptable level in food established by Joint FAO/WHO Expert Committee on Food Additives (JECFA Program Codex Alimentarius Commission. Survey analysis showed that the three highest selling rice varieties during the period when this study was conducted were Sinandomeng, Dinorado and C-4 Dinorado respectively. Lead analysis of rice samples was carried out using Flame Atomic Absorption Spectroscopy. The lead content in both the raw and cooked rice samples were not detected, meaning that the lead concentration were either not present or may be present but is less than the detection limit of the instrument used. The lead concentration in the rice samples from Oriental Mindoro conformed to the standards for food safety for lead content in rice, which is 0.2 mg/kg or 0.2 ppm, set by the Codex Alimentarius Commission.

  6. Determination of gold in geologic materials by solvent extraction and atomic-absorption spectrometry

    Science.gov (United States)

    Huffman, Claude; Mensik, J.D.; Riley, L.B.

    1967-01-01

    The two methods presented for the determination of traces of gold in geologic materials are the cyanide atomic-absorption method and the fire-assay atomic-absorption method. In the cyanide method gold is leached with a sodium-cyanide solution. The monovalent gold is then oxidized to the trivalent state and concentrated by extracting into methyl isobutyl ketone prior to estimation by atomic absorption. In the fire-assay atomic-absorption method, the gold-silver bead obtained from fire assay is dissolved in nitric and hydrochloric acids. Gold is then concentrated by extracting into methyl isobutyl ketone prior to determination by atomic absorption. By either method concentrations as low as 50 parts per billion of gold can be determined in a 15-gram sample.

  7. Determination of antimony by using tungsten trap atomic absorption spectrometry

    Science.gov (United States)

    Titretir, Serap; Kendüzler, Erdal; Arslan, Yasin; Kula, İbrahim; Bakırdere, Sezgin; Ataman, O. Yavuz.

    2008-08-01

    An electrically heated tungsten coil was used as a trap in the determination of antimony. The technique consists of three steps. Initially, SbH 3 is formed by hydride generation procedure; then the analyte species in vapor form are transported to W-coil trap heated at 370 °C. Following the preconcentration step, the trap is heated to 895 °C; analyte species are revolatilized and transported to the flame-heated quartz atom cell where atomization and the formation of signal take place. The experimental parameters were optimized both for trap and no-trap studies. The most important experimental parameters are concentrations of HCl and NaBH 4 solutions, H 2 and Ar gas flow rates, and collection and revolatilization temperatures of W-coil. Accuracy was tested using a certified reference material, waste water EU-L-1. Limit of detection for the system is 16 ng l - 1 using a sample of 36 ml collected in 4.0 min. Enhancement factor in sensitivity was 17.

  8. Determination of antimony by using tungsten trap atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Titretir, Serap [Department of Chemistry, Inoenue University, 44065 Malatya (Turkey); Kenduezler, Erdal [Department of Primary Education, Faculty of Education, Ahi Evran University, 40100 Kirsehir (Turkey); Arslan, Yasin [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Chemistry, Atatuerk University, 25240 Erzurum (Turkey); Kula, Ibrahim [Department of Chemistry, Mugla University, 48000 Mugla (Turkey); Bakirdere, Sezgin [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Chemistry, Zonguldak Karaelmas University, 67100 Zonguldak (Turkey); Ataman, O. Yavuz. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey)], E-mail: ataman@metu.edu.tr

    2008-08-15

    An electrically heated tungsten coil was used as a trap in the determination of antimony. The technique consists of three steps. Initially, SbH{sub 3} is formed by hydride generation procedure; then the analyte species in vapor form are transported to W-coil trap heated at 370 deg. C. Following the preconcentration step, the trap is heated to 895 deg. C; analyte species are revolatilized and transported to the flame-heated quartz atom cell where atomization and the formation of signal take place. The experimental parameters were optimized both for trap and no-trap studies. The most important experimental parameters are concentrations of HCl and NaBH{sub 4} solutions, H{sub 2} and Ar gas flow rates, and collection and revolatilization temperatures of W-coil. Accuracy was tested using a certified reference material, waste water EU-L-1. Limit of detection for the system is 16 ng l{sup -1} using a sample of 36 ml collected in 4.0 min. Enhancement factor in sensitivity was 17.

  9. Atomic absorption determination of tin in foods: collaborative study.

    Science.gov (United States)

    Elkins, E R; Sulek, A

    1979-09-01

    Samples of green beans, applesauce, and a fruit juice were fortified with tin at 3 levels. Collaborators were asked to digest the samples, using HNO3-H2SO4, add methanol to enhance the absorption signal, and aspirate directly, using a nitrous oxide-acetylene flame. Results were received from 8 laboratories including 4 from Europe. However, only 6 laboratories used the prescribed methodology. All results were considered acceptable. The method has been adopted as interim official first action.

  10. Determination of cadmium in biodiesel using microemulsion and electrothermal atomization atomic absorption spectrometry.

    Science.gov (United States)

    Lima, Adriana S; Silva, Deise G; Teixeira, Leonardo S G

    2015-01-01

    This work aimed to prepare biodiesel microemulsions for the subsequent quantification of cadmium via graphite furnace atomic absorption spectrometry (GFAAS). The biodiesel samples were prepared using n-propanol as an emulsifier, 10% (v/v) nitric acid as the aqueous phase, and biodiesel. Pseudoternary phase diagrams were constructed to determine the microemulsion region with the specified components. The optimized conditions for microemulsion formation were 57.6% (v/v) n-propanol, 21.2% (v/v) biodiesel, and 21.2% (v/v) nitric acid solution. The stability of the microemulsified system was investigated using aqueous and organic standards, and the system was found to be stable for at least 240 min. The applied pyrolysis and atomization temperatures were 800 and 2000 °C, respectively, and 5 μg of aluminum was used as the chemical modifier. The obtained limits of detection and quantification were 0.2 and 0.5 μg kg(-1), respectively, and the characteristic mass was 1.6 pg. The precision, expressed as the relative standard deviation (% R.S.D., n = 10), was 2.5% for a sample with a cadmium concentration of 6.5 μg kg(-1). The accuracy was determined from addition and recovery experiments, with results varying from 93 to 108% recovery. This study demonstrates that the proposed method based on the use of a microemulsion formation in sample preparation can be applied as an efficient alternative for the determination of cadmium in biodiesel by GFAAS. Cadmium determination in biodiesel samples of different origins (soybean, corn, cotton, and sunflower) was evaluated after acid digestion using the inductively coupled plasma-mass spectrometry (ICP-MS) technique, and the obtained results were compared to the results obtained using the proposed method. The paired t test (95% confidence level) did not show significant differences. The concentrations of cadmium found ranged from 5.3 to 8.0 μg kg(-1).

  11. Determination of vanadium in food and traditional Chinese medicine by graphite furnace atomic absorption spectroscopy

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Various experimental conditions were described for the vanadium determination by graphite furnace atomic ab-sorption spectroscopy (GFAAS). The experiments showed that when atomization took place under the conditions where thecombination of a pyrolytic coating graphite tube and fast raising temperature were used and the temperature was stable, thesignal peak shapes could be improved, the sensitivity was enhanced, and the memory effect was removed. The vanadium infood and traditional Chinese medicinal herbs can be accurately determined using the standard curve method.

  12. Direct determination of selenoproteins in polyvinylidene difluoride membranes by electrothermal atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Sidenius, U; Gammelgaard, Bente

    2000-01-01

    A method for the direct determination of selenoproteins in plastic membranes after protein separation by gel electrophoresis was developed. Quantification was based on the determination of the selenium content of the proteins by electrothermal atomic absorption spectrometry (ET-AAS) after manual...... were excised and chemical modifier was added on top of the excised membrane prior to atomic absorption measurement. Acceptable linearity was achieved in the range 2-10 ng Se, corresponding to selenium concentrations close to 1 mg/L, when aqueous solutions of selenomethionine standard as well...

  13. DETERMINING BERYLLIUM IN DRINKING WATER BY GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROSCOPY

    Science.gov (United States)

    A direct graphite furnace atomic absorption spectroscopy method for the analysis of beryllium in drinking water has been derived from a method for determining beryllium in urine. Ammonium phosphomolybdate and ascorbic acid were employed as matrix modifiers. The matrix modifiers s...

  14. Direct microcomputer controlled determination of zinc in human serum by flow injection atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Simonsen, Kirsten Wiese; Nielsen, Bent; Jensen, Arne;

    1986-01-01

    A procedure is described for the direct determination of zinc in human serum by fully automated, microcomputer controlled flow injection atomic absorption spectrometry (Fl-AAS). The Fl system is pumpless, using the negative pressure created by the nebuliser. It only consists of a three-way valve...

  15. Chemical modifiers in electrothermal atomic absorption determination of Platinum and Palladium containing preparations in blood serum

    Directory of Open Access Journals (Sweden)

    Аntonina Alemasova

    2012-11-01

    Full Text Available The biological liquids matrixes influence on the characteristic masses and repeatability of Pt and Pd electrothermal atomic absorption spectroscopy (ETAAS determination was studied. The chemical modifiers dimethylglyoxime and ascorbic acid for matrix interferences elimination and ETAAS results repeatability improvement were proposed while bioliquids ETAAS analysis, and their action mechanism was discussed.

  16. Determination of Trace Iron in High Purity Sodium Fluoride by Graphite Furnace Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A method is described for the direct determination of iron in high purity sodium fluoride using graphite furnace atomic absorption spectrometry. Interferences caused by the matrix are investigated. It is shown that the ashing temperature can be increased to 1 400°C and matrix interferences eliminated, the sensi tivity of iron increased in 1.27 fold by the addition of nickel nitrate. The method is applied to the determina tion of iron in sodium fluoride and satisfactory results are obtained.

  17. Determination of diethyllead in the urine by flameless atomic absorption spectrometry.

    OpenAIRE

    Turlakiewicz, Z; Jakubowski, M.; Chmielnicka, J

    1985-01-01

    A method for the determination of diethyllead in urine by flameless atomic absorption spectrometry after chelation with glyoxal-bis (2-hydroxyanil) and extraction of the formed complex with methyl isobutyl ketone is described. The method is specific in relation to both triethyllead and inorganic lead. The limit of detection was 3.2 micrograms Pb/l and the relative standard deviation in the concentration range 20-100 micrograms Pb/l was 0.076.

  18. Determination of trace elements in paints by direct sampling graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Bentlin, Fabrina R S; Pozebon, Dirce; Mello, Paola A; Flores, Erico M M

    2007-10-17

    A direct sampling graphite furnace atomic absorption spectrometric (DS-GFAAS) method for the determination of Cd, Pb, Cr, Ni, Co and Cu in paints has been developed. Serigraphy, acrylic and tattoo paints were analysed. Approaches like pyrolysis and atomization temperatures, modifiers and sample mass introduced in the atomizer were studied. Quantification was performed using calibration curves measured with aqueous standard solutions pipetted onto the platform. The sample mass introduced in the graphite tube ranged from 0.02 to 8.0 mg. Palladium was used as modifier for Cd, Pb and Cu, while Mg(NO3)2 was used for Co. For Ni determination, the graphite platform was covered with carbon powder. The characteristic masses of Cd, Pb, Cr, Ni, Co and Cu were 1.4, 22.5, 7.9, 11.0, 9.6 and 12.5 pg, while the limits of detection were 0.0004, 0.001, 0.03, 0.22, 0.11 and 0.05 microg g(-1) of Cd, Pb, Cr, Ni, Co and Cu, respectively. The accuracy was determined by comparison of the results with those obtained by inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GFAAS), using liquid sampling of digests. For matrix characterization, major and minor elements (Al, Mg, Ba, Ca, Cr, Cu, Pb, Sr, Ti and Mg) were determined by inductively coupled plasma optical emission spectrometry (ICP OES).

  19. Determination of trace elements in paints by direct sampling graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bentlin, Fabrina R.S. [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, UFRGS, 91501-970 Porto Alegre, RS (Brazil); Pozebon, Dirce [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, UFRGS, 91501-970 Porto Alegre, RS (Brazil)], E-mail: dircepoz@iq.ufrgs.br; Mello, Paola A.; Flores, Erico M.M. [Departamento de Quimica, Universidade Federal de Santa Maria, UFSM, 97105-900 Santa Maria, RS (Brazil)

    2007-10-17

    A direct sampling graphite furnace atomic absorption spectrometric (DS-GFAAS) method for the determination of Cd, Pb, Cr, Ni, Co and Cu in paints has been developed. Serigraphy, acrylic and tattoo paints were analysed. Approaches like pyrolysis and atomization temperatures, modifiers and sample mass introduced in the atomizer were studied. Quantification was performed using calibration curves measured with aqueous standard solutions pipetted onto the platform. The sample mass introduced in the graphite tube ranged from 0.02 to 8.0 mg. Palladium was used as modifier for Cd, Pb and Cu, while Mg(NO{sub 3}){sub 2} was used for Co. For Ni determination, the graphite platform was covered with carbon powder. The characteristic masses of Cd, Pb, Cr, Ni, Co and Cu were 1.4, 22.5, 7.9, 11.0, 9.6 and 12.5 pg, while the limits of detection were 0.0004, 0.001, 0.03, 0.22, 0.11 and 0.05 {mu}g g{sup -1} of Cd, Pb, Cr, Ni, Co and Cu, respectively. The accuracy was determined by comparison of the results with those obtained by inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GFAAS), using liquid sampling of digests. For matrix characterization, major and minor elements (Al, Mg, Ba, Ca, Cr, Cu, Pb, Sr, Ti and Mg) were determined by inductively coupled plasma optical emission spectrometry (ICP OES)

  20. Some problems connected with boron determination by atomic absorption spectroscopy and the sensitivity improvement

    Directory of Open Access Journals (Sweden)

    JELENA J. SAVOVIC

    2001-08-01

    Full Text Available Two atomizers were compared: an N2O–C2H2 flame and a stabilized U-shaped DC arc with aerosol supply. Both the high plasma temperature and the reducing atmosphere obtained by acetylene addition to the argon stream substantially increase the sensitivity of boron determination by atomic absorption spectroscopy (AAS when the arc atomizer is used. The results were compared with those for silicon as a control element. The experimental characteristic concentrations for both elements were compared with the computed values. The experimentally obtained characteristic concentration for boron when using the arc atomizer was in better agreement with the calculated value. It was estimated that the influence of stable monoxide formation on the sensitivity for both elements was about the same, but reduction of analyte and formation of non-volatile carbide particles was more important for boron, which is the main reason for the low sensitivity of boron determination using a flame atomizer. The use of an arc atomizer suppresses this interference and significantly improves the sensitivity of the determination.

  1. Determination of Calcium in Cereal with Flame Atomic Absorption Spectroscopy: An Experiment for a Quantitative Methods of Analysis Course

    Science.gov (United States)

    Bazzi, Ali; Kreuz, Bette; Fischer, Jeffrey

    2004-01-01

    An experiment for determination of calcium in cereal using two-increment standard addition method in conjunction with flame atomic absorption spectroscopy (FAAS) is demonstrated. The experiment is intended to introduce students to the principles of atomic absorption spectroscopy giving them hands on experience using quantitative methods of…

  2. Determination of copper, zinc and iron in broncho-alveolar lavages by atomic absorption spectroscopy.

    Science.gov (United States)

    Harlyk, C; Mccourt, J; Bordin, G; Rodriguez, A R; van der Eeckhout, A

    1997-11-01

    Concentrations of Zn, Cu and Fe were measured in 157 broncho-alveolar lavages (BAL), before and after centrifugation, collected at the Leuven University Hospital (Belgium). Zn was measured by flame-atomic absorption spectroscopy, using direct calibration, while Cu and Fe were determined by electrothermal atomic absorption spectroscopy, using the method of standard additions. For Fe only 56 samples were measured. Most of the studied elements are present in the liquid phase (supernatant). About 90% of Cu concentrations lie between 0 and 15 micrograms/kg, while 90% of Zn concentrations are lower than 230 micrograms/kg, with 30% between 30 and 70 micrograms/kg, and 50% between 100 and 200 micrograms/kg. There seems to be a reverse relationship between Cu and Zn levels with high Cu going along with low Zn and vice versa.

  3. The determination of aluminum, copper, iron, and lead in glycol formulations by atomic absorption spectroscopy

    Science.gov (United States)

    1977-01-01

    Initial screening tests and the results obtained in developing procedures to determine Al, Cu, Fe, and Pb in glycol formulations are described. Atomic absorption completion was selected for Cu, Fe and Pb, and after comparison with emission spectroscopy, was selected for Al also. Before completion, carbon, iron, and lead are extracted with diethyl dithio carbamate (DDC) into methyl isobutyl ketone (MIBK). Aluminum was also extracted into MIBK using 8-hydroxyquinoline as a chelating agent. As little as 0.02 mg/l carbon and 0.06 mg/l lead or iron may be determined in glycol formulations. As little as 0.3 mg/l aluminum may be determined.

  4. Determination of heavy metals in solid emission and immission samples using atomic absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fara, M.; Novak, F. [EGU Prague, PLC, Bichovice, Prague (Czechoslovakia)

    1995-12-01

    Both flame and electrothermal methods of atomic absorption spectroscopy (AAS) have been applied to the determination of Al, As, Be, Ca, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, TI, Se, V and Zn in emission and emission (deposition) samples decomposed in open PTFE test-tubes by individual fuming-off hydrofluoric, perchloroic and nitric acid. An alternative hydride technique was also used for As and Se determination and Hg was determined using a self-contained AAS analyzer. A graphite platform proved good to overcome non-spectral interferences in AAS-ETA. Methods developed were verified by reference materials (inc. NBS 1633a).

  5. Determination of tellurium by hydride generation with in situ trapping flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Matusiewicz, H.; Krawczyk, M. [Politechn Poznanska, Poznan (Poland)

    2007-03-15

    The analytical performance of coupled hydride generation - integrated atom trap (HG-IAT) atomizer flame atomic absorption spectrometry (FAAS) system was evaluated for determination of Te in reference material (GBW 07302 Stream Sediment), coal fly ash and garlic. Tellurium, using formation of H{sub 2}Te vapors, is atomized in air-acetylene flame-heated IAT. A new design HG-IAT-FAAS hyphenated technique that would exceed the operational capabilities of existing arrangernents (a water-cooled single silica tube, double-slotted quartz tube or an 'integrated trap') was investigated. An improvement in detection limit was achieved compared with using either of the above atom trapping techniques separately. The concentration detection limit, defined as 3 times the blank standard deviation (3{sigma}), was 0.9 ng mL{sup -1} for Te. For a 2 min in situ preconcentration time (sample volume of 2 mL), sensitivity enhancement compared to flame AAS, was 222 fold, using the hydride generation atom trapping technique. The sensitivity can be further improved by increasing the collection time. The precision, expressed as RSD, was 7.0% (n = 6) for Te. The accuracy of the method was verified using a certified reference material (GBW 07302 Stream Sediment) by aqueous standard calibration curves. The measured Te contents of the reference material was in agreement with the information value. The method was successfully applied to the determination of tellurium in coal fly ash and garlic.

  6. Determination of total magnesium in biological samples using electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Hulanicki, Adam; Godlewska, Beata; Brzóska, Malgorzata

    1995-11-01

    Magnesium content is an important diagnostic parameter in medicine. It is recognized that its determination in one compartment is not sufficient for reliable information about the magnesium status in the body. In addition to the common procedures of magnesium determination in blood by flame atomic absorption spectrometry, the procedure of electrothermal atomization has also been developed and applied to the analysis of blood fractions, mononuclear cells and isolated nuclei of liver cells. Electrothermal atomization is preferred in cases where the sample size is limited and the magnesium content low. The total errors are in the order of 3-4%. Various techniques of sample pretreatment have been tested and direct dilution with 0.05 mol l -1 nitric acid was optimal when the samples were not mineralized. The calibration graph based on standards containing albumin was found to give the best results, as the form of magnesium in the samples may influence the ashing and atomization processes. Good agreement was obtained for determination of magnesium in standard serum. The results are compared with those obtained by the standard flame atomization technique.

  7. Radiation trapping in atomic absorption spectroscopy at lead determination in different matricies

    Energy Technology Data Exchange (ETDEWEB)

    El-Gohary, Z. [Department of Physics, Faculty of Science, Menoufia University, Shebin El-Koom (Egypt)]. E-mail: zhelgohary@yahoo.com

    2005-08-15

    The determination of lead by flame atomic absorption analysis in the presence of Sn and Fe atoms and different matrices such as OH and SO{sub 3} was investigated with the objective of understanding the spectral interference processes at the analytical lines 283.31 nm for a wide range of concentration. The radiation trapping factor was interpreted and evaluated assuming Voigt distribution of the atomic and rotational lines in the flame. The radiation trapping factor was increased by increasing the number density (plasma of the absorbing medium is optically thick). In plasma, there is a certain point of equilibrium between the trapping and the escaping of radiation, which is relevant to 50% of absorption. The spectral background interference can cause a variation of the number density at equilibrium point as a result of the degree of overlap with the analytical line. The spectral background interference can be easily avoided by using another resonance absorption line for the analysis. The chemical modification of the matrix is applied to minimize the interference effect. Nitric acid, ammonium nitrate and magnesium nitrate are most commonly recommended as matrix modifiers.

  8. Radiation trapping in atomic absorption spectroscopy at lead determination in different matricies

    Science.gov (United States)

    El-Gohary, Z.

    2005-08-01

    The determination of lead by flame atomic absorption analysis in the presence of Sn and Fe atoms and different matrices such as OH and SO3 was investigated with the objective of understanding the spectral interference processes at the analytical lines 283.31 nm for a wide range of concentration. The radiation trapping factor was interpreted and evaluated assuming Voigt distribution of the atomic and rotational lines in the flame. The radiation trapping factor was increased by increasing the number density (plasma of the absorbing medium is optically thick). In plasma, there is a certain point of equilibrium between the trapping and the escaping of radiation, which is relevant to 50% of absorption. The spectral background interference can cause a variation of the number density at equilibrium point as a result of the degree of overlap with the analytical line. The spectral background interference can be easily avoided by using another resonance absorption line for the analysis. The chemical modification of the matrix is applied to minimize the interference effect. Nitric acid, ammonium nitrate and magnesium nitrate are most commonly recommended as matrix modifiers.

  9. [Determination of trace selenium in edible fungi with graphite furnace atomic absorption spectroscopy].

    Science.gov (United States)

    Tie, Mei; Zhang, Wei; Li, Jing; Jing, Kui; Zang, Shu-liang; Li, Hua-wei

    2006-01-01

    In the present article, samples were digested by a quartz high-pressure digestion pot, reducing the loss of selenium in digestion. The content of selenium in edible fungi was determined by using graphite furnace atomic absorption spectroscopy, and the results showed that when the content of selenium in edible fungi was determined by using 1% Ni(NO3)2 as a matrix modifier, ashing temperature of 500 degreed C, and atomization temperature of 2 500 degrees C, and rectifying background by deuterium light, the recovery was in the range of 92.1%-115.5%, the relative standard deviation of the method was 1.28%, and the limit of detection was 15.8 microg x L(-1). The method was suitable for the determination of trace selenium in edible fungi with the advantages of being simple, rapid, sensitive, stable and accurate etc., and the results were satisfactory.

  10. Determination of traces of silver in waters by anion exchange and atomic absorption spectrophotometry

    Science.gov (United States)

    Chao, T.T.; Fishman, M. J.; Ball, J.W.

    1969-01-01

    A method has been developed for the accurate determination of 0.1-1 ??g of silver per liter of water. The method permits stabilization of silver in water without loss to container walls. Optimum conditions have been established for the complete recovery of silver from water with an anion-exchange column, for quantitative elution of silver from the resin, and for measurement of silver by atomic absorption spectrophotometry after chelation with ammonium pyrrolidine dithiocarbamate and extraction of the chelate with MIBK. Silver in the 1-10 ??g 1 range can be determined by extraction without pre-concentration on an ion-exchange resin. ?? 1969.

  11. Determination of Aluminum Concentration in Seawater by Colorimetry and Atomic Absorption Spectroscopy.

    Science.gov (United States)

    1972-11-30

    this was also high. 5 . ,Irj ~ - • lri*; llo. TALLE 2 ATOMIC ABSORPTION SPECTROSCOPY DETEPIJINATION OF ALUMINU1 CONCENTRATIO11 OF SEAWATER OCEAN...Concentration in Seawater by Colorimetr-y and Atomic Absorption Spectroscopy Charles A. Greene, Jr. and Everett N. Jones Ocean Science Department T14

  12. Determination of vanadium in mussels by electrothermal atomic absorption spectrometry without chemical modifiers

    Energy Technology Data Exchange (ETDEWEB)

    Saavedra, Y.; Fernandez, P. [Centro de Control do Medio Marino, Peirao de Vilaxoan s/n, Vilagarcia de Arousa, 36611 Pontevedra (Spain); Gonzalez, A. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Quimica, 15706, Santiago de Compostela (Spain)

    2004-05-01

    A method was developed for the quantitative determination of total vanadium concentration in mussels via electrothermal atomic absorption spectrometry (ETAAS). After the microwave digestion of the samples, a program using temperatures of 1600 C and 2600 C for ashing and atomization respectively, without any matrix modifiers, allowed us to obtain results that were satisfactory since they agreed closely with certified reference material values. The detection limit was 0.03 mg kg{sup -1} (dry weight), indicating that the method is suitable for the analysis of mussel samples. This determination was compared with matrix modifiers that have been reported previously. The method was applied to various cultivated and wild mussels from the Galician coast, yielding levels below 1 mg kg{sup -1} (wet weight). (orig.)

  13. Determination of ruthenium in pharmaceutical compounds by graphite furnace atomic absorption spectroscopy.

    Science.gov (United States)

    Jia, Xiujuan; Wang, Tiebang; Bu, Xiaodong; Tu, Qiang; Spencer, Sandra

    2006-04-11

    A graphite furnace atomic absorption (GFAA) spectrometric method for the determination of ruthenium (Rh) in solid and liquid pharmaceutical compounds has been developed. Samples are dissolved or diluted in dimethyl sulfoxide (DMSO) without any other treatment before they were analyzed by GFAA with a carefully designed heating program to avoid pre-atomization signal loss and to achieve suitable sensitivity. Various inorganic and organic solvents were tested and compared and DMSO was found to be the most suitable. In addition, ruthenium was found to be stable in DMSO for at least 5 days. Spike recoveries ranged from 81 to 100% and the limit of quantitation (LOQ) was determined to be 0.5 microg g(-1) for solid samples or 0.005 microg ml(-1) for liquid samples based a 100-fold dilution. The same set of samples was also analyzed by ICP-MS with a different sample preparation method, and excellent agreement was achieved.

  14. Electrothermal atomization atomic absorption spectrometry for the determination of lead in urine: results of an interlaboratory study

    Science.gov (United States)

    Parsons, Patrick J.; Slavin, Walter

    1999-05-01

    Results of an interlaboratory study are reported for the determination of lead in urine. Two levels of a lyophilized material containing biologically-bound lead were prepared using pooled urine obtained from lead-poisoned children undergoing the CaNa 2EDTA mobilization test. The materials were circulated to a group of reference laboratories that participate in the `New York State Proficiency Testing Program for Blood Lead'. Results of the initial round-robin gave all-method consensus target values of 145±22 μg/l (S.D.) for lot 17 and 449±43 μg/l (S.D.) for lot 20. The interlaboratory exercise was repeated some 5 years later and consensus target values were re-calculated using the grand mean (excluding outliers) of results reported by laboratories using electrothermal atomization atomic absorption spectrometry (ETAAS). The re-calculated target values were 139±10 μg/l (S.D.) and 433±12 μg/l (S.D.). The urine reference materials were also analyzed for lead by several laboratories using other instrumental techniques including isotope dilution (ID), inductively coupled plasma (ICP) mass spectrometry (MS), flame atomic absorption with extraction, ICP-atomic emission spectrometry, ID-gas chromatography MS and flow injection-hydride generation AAS, thus providing a rich source of analytical data with which to characterize them. The materials were also used in a long-term validation study of an ETAAS method developed originally for blood lead determinations that has since been used unmodified for the determination of lead in urine also. Recently, urine lead method performance has been tracked in a proficiency testing program specifically for this analysis. In addition, a number of commercial control materials have been analyzed and evaluated.

  15. Determination of cadmium and lead in urine by derivative flame atomic absorption spectrometry using the atom trapping technique

    Science.gov (United States)

    Han-wen, Sun; De-qiang, Zhang; Li-li, Yang; Jian-min, Sun

    1997-06-01

    A method is described for the determinations of cadmium and lead in urine by derivative flame atomic absorption spectrometry with a modified water-cooled stainless steel atom trapping tube. The effects of the trap position, the flame conditions, the coolant flow rates, and the collection time were studied. With a 1 min collection time, the characteristic concentrations (derivative absorbance of 0.0044) for cadmium and lead were 0.028 and 1.4 μg L -1, the detection limits (3σ) were 0.02 and 0.27 μg L -1, respectively. The detection limits and sensitivities of the proposed method were 2 and 3 orders of magnitude higher for 1-3 min collection time than those of conventional flame atomic absorption spectrometry for cadmium and lead, respectively. Urine samples from a small population of normal individuals have been analyzed for cadmium and lead by the proposed method. Satisfactory recoveries of 91-110% and 91-106%, for Cd and Pb were obtained with these urine samples.

  16. Exploiting flow Injection and sequential injection schemes for trace metal determinations by electrothermal atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Hansen, Elo Harald

    Determination of low or trace-level amounts of metals by electrothermal atomic absorption spectrometry (ETAAS) often requires the use of suitable preconcentration and/or separation procedures in order to attain the necessary sensitivity and selectivity. Such schemes are advantageously executed....../preconcentration procedures have been suggested and applied, such as liquid-liquid extraction, (co)precipitation with collection in knotted reactors, adsorption, hydride generation, or ion-exchange. Selected examples of some of these procedures will be discussed. Emphasis will be placed on the use of FI...

  17. Method 200.12 - Determination of Trace Elements in Marine Waters by StabilizedTemperature Graphite Furnace Atomic Absorption

    Science.gov (United States)

    This method provides procedures for the determination of total recoverable elements by graphite furnace atomic absorption (GFAA) in marine waters, including estuarine, ocean and brines with salinities of up to 35 ppt.

  18. Slurry analysis after lead collection on a sorbent and its determination by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Baysal, Asli; Tokman, Nilgun [Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, 34469 Maslak-Istanbul (Turkey); Akman, Suleyman [Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, 34469 Maslak-Istanbul (Turkey)], E-mail: akmans@itu.edu.tr; Ozeroglu, Cemal [Istanbul University, Department of Chemistry, Faculty of Engineering, 34320 Avcilar-Istanbul (Turkey)

    2008-02-11

    In this study, in order to eliminate the drawbacks of elution step and to reach higher enrichment factors, a novel preconcentration/separation technique for the slurry analysis of sorbent loaded with lead prior to its determination by electrothermal atomic absorption spectrometry was described. For this purpose, at first, lead was collected on ethylene glycol dimethacrylate methacrylic acid copolymer (EGDMA-MA) treated with ammonium pyrolidine dithiocarbamate (APDC) by conventional batch technique. After separation of liquid phase, slurry of the sorbent was prepared and directly pipetted into graphite furnace of atomic absorption spectrophotometer. Optimum conditions for quantitative sorption and preparation of the slurry were investigated. A 100-fold enrichment factor could be easily reached. The analyte element in certified sea-water and Bovine-liver samples was determined in the range of 95% confidence level. The proposed technique was fast and simple and the risks of contamination and analyte loss were low. Detection limit (3{delta}) for Pb was 1.67 {mu}g l{sup -1}.

  19. Alternative approaches to correct interferences in the determination of boron in shrimps by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Pasias, I.N.; Pappa, Ch.; Katsarou, V.; Thomaidis, N.S., E-mail: ntho@chem.uoa.gr; Piperaki, E.A.

    2014-02-01

    The aim of this study is to propose alternative techniques and methods in combination with the classical chemical modification to correct the major matrix interferences in the determination of boron in shrimps. The performance of an internal standard (Ge) for the determination of boron by the simultaneous multi-element atomic absorption spectrometry was tested. The use of internal standardization increased the recovery from 85.9% to 101% and allowed a simple correction of errors during sampling preparation and heating process. Furthermore, a new preparation procedure based on the use of citric acid during digestion and dilution steps improved the sensitivity of the method and decreased the limit of detection. Finally, a comparative study between the simultaneous multi-element atomic absorption spectrometry with a longitudinal Zeeman-effect background correction system, equipped with a transversely-heated graphite atomizer and the single element atomic absorption spectrometry with a D{sub 2} background correction system, equipped with an end-heated graphite atomizer was undertaken to investigate the different behavior of boron in both techniques. Different chemical modifiers for the determination of boron were tested with both techniques. Ni-citric acid and Ca were the optimal chemical modifiers when simultaneous multi-element atomic absorption spectrometry and single-element atomic absorption spectrometry were used, respectively. By using the single-element atomic absorption spectrometry, the calculated characteristic mass was 220 pg and the calculated limit of detection was 370 μg/kg. On the contrary, with simultaneous multi-element atomic absorption spectrometry, the characteristic mass was 2200 pg and the limit of detection was 5.5 mg/kg. - Highlights: • New approaches were developed to cope with interferences of B determination by ETAAS • Ge was used as internal standard for the determination of B by simultaneous ETAAS • Citric acid was used during

  20. Preconcentration and Determination of Chromium Species Using Octadecyl Silica Membrane Disks and Flame Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    MOGHIMI Ali; SABER-TEHRANI Mohammad; WAQIF-HUSAIN Syed; MOHAMMADHOSSEINI Majid

    2007-01-01

    A novel and selective method for the fast determination of trace amounts of chromium species in water samples has been developed.The procedure is based on the selective formation of chromium diethyldithiocarbamate complexes at different pH in the presence of Mn(Ⅱ) as an enhancement agent of chromium signals followed by elutionwith organic eluents and determination by atomic flame absorption spectrometry.The maximum capacity of the employed disks was found to be (3964±3) μg and (376±2) μg for Cr(Ⅲ) and Cr(Ⅵ),respectively.The detection limit of the proposed method is 49 and 43 ng·L-1 for Cr(Ⅲ) and Cr(Ⅵ),respectively.The proposed method was successfully applied for determination of chromium species Cr(Ⅲ) and Cr(Ⅵ) in different water samples.

  1. Preconcentration of Vanadium(Ⅴ) on Crosslinked Chitosan and Determination by Graphite Furnace Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new method is proposed for the preconcentration of vanadium(Ⅴ) with crosslinked chitosan (CCTS) and determination by graphite furnace atomic absorption spectrometry (GFAAS). The adsorption rate of vanadium(Ⅴ) by CCTS was 97% at pH 4.0, and vanadium(Ⅴ) was eluted from crosslinked chitosan with 2 mL 2.0 mol*L-1 chlorhydric acid and determined by GFAAS. The detection limit (3σ,n=7) for vanadium(Ⅴ) was 4.8×1 0-12g and the relative standard deviation (R.S.D) at concentration level of 2.6 μg*L-1 is less than 3.6%. The method shows a good selectivity and high sensitivity, and it was applied to determination of vanadium(Ⅴ) in oyster and water samples. The analytic recoveries are (97±5)%.

  2. DETERMINATION OF NICKLE CONTENTS IN SELECTED VANASPATI GHEE THROUGH ATOMIC ABSORPTION SPECTROPHOTOMETER

    Directory of Open Access Journals (Sweden)

    Waqas Ahmad

    2014-12-01

    Full Text Available To convert vegetable edible oils into vanaspati ghee, nickel is used as a catalyst in the hydrogenation process. A simple and fast method for the trace level determination of nickel in ghee is reported. In this different methods were applied for the extraction of residual nickel from ghee samples. Using toluene, as organic solvents, an acid mixture was used for the extraction of nickel. Extracted nickel was quantified with atomic absorption. Among the organic solvents, toluene proved to be the best solvent mediating a 95% extraction of nickel from ghee samples. Nickel was extracted and determined in ten different brands of ghee and in all samples its amount was well above the permissible limit of WHO (0.2 μg/g. Other metals like lead, zinc, copper, and cadmium were also determined and their concentrations were found to be much below the WHO permissible limits.

  3. Method for the determination of cobalt from biological products with graphite furnace atomic absorption spectrometer

    Science.gov (United States)

    Zamfir, Oana-Liliana; Ionicǎ, Mihai; Caragea, Genica; Radu, Simona; Vlǎdescu, Marian

    2016-12-01

    Cobalt is a chemical element with symbol Co and atomic number 27 and atomic weight 58.93. 59 Co is the only stable cobalt isotope and the only isotope to exist naturally on Earth. Cobalt is the active center of coenzymes called cobalamin or cyanocobalamin the most common example of which is vitamin B12. Vitamin B12 deficiency can potentially cause severe and irreversible damage, especially to the brain and nervous system in the form of fatigue, depression and poor memory or even mania and psychosis. In order to study the degree of deficiency of the population with Co or the correctness of treatment with vitamin B12, a modern optoelectronic method for the determination of metals and metalloids from biological samples has been developed, Graphite Furnace - Atomic Absorption Spectrometer (GF- AAS) method is recommended. The technique is based on the fact that free atoms will absorb light at wavelengths characteristic of the element of interest. Free atoms of the chemical element can be produced from samples by the application of high temperatures. The system GF-AAS Varian used as biological samples, blood or urine that followed the digest of the organic matrix. For the investigations was used a high - performance GF-AAS with D2 - background correction system and a transversely heated graphite atomizer. As result of the use of the method are presented the concentration of Co in the blood or urine of a group of patient in Bucharest. The method is sensitive, reproducible relatively easy to apply, with a moderately costs.

  4. Determination of zinc in serum, blood, and ultrafiltrate fluid from patients on hemofiltration by graphite furnace/atomic absorption spectroscopy or flow injection analysis/atomic absorption spectroscopy.

    Science.gov (United States)

    de Blas, O J; Rodriguez, R S; Mendez, J H; Tomero, J A; Gomez, B de L; Gonzalez, S V

    1994-01-01

    Two methods were optimized for the determination of zinc in samples of blood, serum, and ultrafiltrate fluid from patients with chronic renal impairment undergoing hemofiltration. In the first procedure, after acid digestion of the samples, Zn in blood and serum is determined by a system coupled to flow injection analysis and atomic absorption spectroscopy. The method is rapid, automated, simple, needs small amounts of sample, and has acceptable analytical characteristics. The analytical characteristics obtained were as follows: determination range of method, 0.05-2.0 ppm of Zn; precision as coefficient of variation (CV), 5.3%; recovery, 95-105%; and detection limit (DL), 0.02 ppm. The second method is optimized for ultrafiltrate fluid because the sensitivity of the first procedure is not suitable for the levels of Zn (ppb or ng/mL) in these samples. The technique chosen was atomic absorption spectroscopy with electrothermal atomization in a graphite furnace. The analytical characteristics obtained were as follows: determination range of method, 0.3-2.0 ppb Zn; CV, 5.7%; recovery, 93-107%; and DL, 0.12 ppb. The methods were used to determine zinc in samples of blood, serum, and ultrafiltrate fluid from 5 patients with chronic renal impairment undergoing hemofiltration to discover whether there were significant differences in the zinc contents of blood, serum, and ultrafiltrate fluid after the hemofiltration process. An analysis of variance of the experimental data obtained from a randomly selected group of 5 patients showed that zinc concentrations in the ultrafiltrate fluid, venous blood, and venous serum do not vary during hemofiltration (p < 0.05), whereas in arterial blood and serum, the time factor has a significant effect.

  5. Evaluation of quartz tubes as atomization cells for gold determination by thermospray flame furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Morzan, Ezequiel; Piano, Ornela; Stripeikis, Jorge; Tudino, Mabel, E-mail: tudino@qi.fcen.uba.ar

    2012-11-15

    This work describes the development of a new analytical procedure able to determine gold by thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) using nickel tubes (NiT) and quartz tubes (QT) as atomization cells. Experiments involving changes in the flow injection operational parameters, reagent concentrations and sizes of the QT were performed in order to optimize sensitivity. Under the same operational conditions, it was observed that the employment of QT increases the sensitivity of gold determination when compared to the nickel tube. Since solutions of highly concentrated hydrochloric acid showed the best performance as carriers, quartz tubes were also preferred due to its greater tolerance to corrosion by mineral acids in comparison to NiT. In addition, changes in the internal diameter of the QT revealed an important improvement in sensitivity for smaller tubes. Under optimized conditions the main figures of merit showed values close to that of graphite furnace atomic absorption spectrometry with the addition of an excellent improvement of the sample throughput. They are: LOD (3 s): 0.004 {mu}g mL{sup -1}, sensitivity: 0.306 ({mu}g mL{sup -1}){sup -1}, RSD% (n = 10, 1 {mu}g mL{sup -1}): 2.5, linear range: 0.01-4 {mu}g mL{sup -1} and sample throughput: 72 h{sup -1}. This new method was employed for the determination of gold in homeopathic medicines with no need of sample digestion. Validation of the analytical results will be shown. A full discussion of the most relevant findings regarding the role of the atomization cell as a strategic key for improving sensitivity will be also provided. - Highlights: Black-Right-Pointing-Pointer Quartz tubes as furnaces in TS-FFAAS. Black-Right-Pointing-Pointer Small tubes for controlling radial dispersion. Black-Right-Pointing-Pointer Improved figures of merit for gold determination. Black-Right-Pointing-Pointer Analysis of homeopathic medicines.

  6. Determination of metal concentration in fat supplements for swine nutrition by atomic absorption spectroscopy.

    Science.gov (United States)

    Cocchi, Marina; Faeti, Valerio; Manfredini, Matteo; Manzini, Daniela; Marchetti, Andrea; Sighinolfi, Simona

    2005-01-01

    The presence of some essential and toxic metals in fat supplements for swine diet was investigated. Collected samples represented a relevant production of the Italian industry. In particular, some samples were enriched with antioxidants or waste cooking oils. The method for the determination of Ca, Cu, Cd, Fe, Mg, Mn, Ni, Pb, and Zn in fat samples was developed by means of a certified reference material (CRM 186) and a representative fatty sample (RFS). All samples were digested in closed vessels in a microwave oven and then analyzed by flame atomic absorption or graphite furnace atomic absorption spectrometry. The entire analytical method provided a satisfactory repeatability and reproducibility confirmed by agreement between the experimental recovery data obtained for the CRM 186 sample and, with the method of standard additions, for the RFS material. The samples generally showed a small amount of metals compared with the recommended daily intake for the essential elements. On the other hand, some samples contained a significant concentration, from an analytical point of view, of Cd, Ni, and Pb. Principal component analysis (PCA) was applied to inspect the experimental data obtained from samples analysis. Basically no differences were detected in terms of metal concentration among the fat supplements analyzed.

  7. Use of flameless atomic absorption spectroscopy in immune cytolysis for nonradioactive determination of killer cell activity.

    Science.gov (United States)

    Borella, P; Bargellini, A; Salvioli, S; Cossarizza, A

    1996-02-01

    We describe here a novel method to evaluate natural killer (NK) cytolytic activity by use of flameless atomic absorption spectroscopy (GF-AAS). This technique may be adopted for use in laboratories equipped with electrothermal atomic absorption spectrometers. Nonradioactive Cr as Na2CrO4 was used to label target cells (K562), and cell lysis was evaluated by measuring Cr released after 4 h of incubation with the effectors. We selected 520 micrograms/L as the optimal dose for labeling targets, between 12 and 20 h as the optimal incubation time, and 10(4) cells as the optimal target size. Advantages of this method include: (a) exclusion of radioactive tracer, with no risk for workers; (b) limited costs; (c) high sensitivity and reproducibility; (d) possibility to store samples; and (e) better control of Cr used for labeling cells due to well-determined, fixed Cr concentrations in the range of nontoxic and linear cellular uptake. Comparison with data obtained by conventional 51Cr labeling of targets killed by the same effectors was excellent, yielding comparable results and corroborating the method.

  8. Determination of cyanide by a flow injection analysis-atomic absorption spectrometric method.

    Science.gov (United States)

    López Gómez, A V; Martínez Calatayud, J

    1998-10-01

    A new flow injection analysis (FIA) procedure is proposed for the indirect atomic absorption spectrometric determination of cyanide. The FIA manifold is based on the insertion of the sample into a distilled water carrier, then the sample flows through a solid-phase reactor filled with silver iodide entrapped in polymeric resin beads. The calibration graph is linear over the range 0.2-6.0 mg l-1 of cyanide (correlation coefficient 0.9974), the detection limit is 0.1 mg l-1, the sample throughput is 193 h-1 and the RSD is 0.8%. The method is simple, quick and more selective than other published FIA procedures. The reproducibility obtained by using different solid-phase reactors and solutions is in the range 2.2-3.1% (RSD). The method was applied to the determination of cyanide in commercial samples such as pharmaceutical formulations and industrial electrolytic baths.

  9. Determination of sodium in foods by flame atomic absorption spectrometry after microwave digestion: NMKL interlaboratory study.

    Science.gov (United States)

    Julshamn, Kaare; Lea, Per; Norli, Hilde Skaar

    2005-01-01

    Nine laboratories participated in an interlaboratory method performance (collaborative) study of a method for the determination of sodium in foods by flame atomic absorption spectrometry after wet digestion, using a microwave oven technique. Before the study, the laboratories were able to practice on samples with defined sodium levels (pretrial test). The method was tested on a total of 6 foods (broccoli, carrot, bread, saithe fillet, pork, and cheese) with sodium concentrations of 1480-8260 mg/kg. The materials were presented to the participants in the study as blind duplicates, and the participants were asked to perform single determinations for each sample. The repeatability relative standard deviations (RSDr) for sodium ranged from 1.9 to 6.5%. The reproducibility relative standard deviations (RSDR) ranged from 4.2 to 6.9%. The HorRat values ranged from 0.9 to 1.6.

  10. Slurry sampling graphite furnace atomic absorption spectrometry: determination of trace metals in mineral coal.

    Science.gov (United States)

    Silva, M M; Goreti, M; Vale, R; Caramão, E B

    1999-12-06

    A procedure for lead, cadmium and copper determination in coal samples based on slurry sampling using an atomic absorption spectrometer equipped with a transversely heated graphite tube atomizer is proposed. The slurries were prepared by weighing the samples directly into autosampler cups (5-30 mg) and adding a 1.5 ml aliquot of a diluent mixture of 5% v/v HNO(3), 0.05% Triton X-100 and 10% ethanol. The slurry was homogenized by manual stirring before measurement. Slurry homogenization using ultrasonic agitation was also investigated for comparison. The effect of particle size and the use of different diluent compositions on the slurry preparation were investigated. The temperature programmes were optimized on the basis of pyrolysis and atomization curves. Absorbance characteristics with and without the addition of a palladium-magnesium modifier were compared. The use of 0.05% m/v Pd and 0.03% m/v Mg was found satisfactory for stabilizing Cd and Pb. The calibration was performed with aqueous standards. In addition, a conventional acid digestion procedure was applied to verify the efficiency of the slurry sampling. Better recoveries of the analytes were obtained when the particle size was reduced to <37 mum. Several certified coal reference materials (BCR Nos. 40, 180, and 181) were analyzed, and good agreement was obtained between the results from the proposed slurry sampling method and the certificate values.

  11. Determination of lead in fine particulates by slurry sampling electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Yu, J C; Ho, K F; Lee, S C

    2001-01-02

    A simple method for determining lead in fine particulates (PM2.5) by using electrothermal atomic absorption spectrometry (ETAAS) has been developed. Particulates collected on Nuclepore filter by using a dichotomous sampler were suspended in diluted nitric acid after ultrasonic agitation. The dislodging efficiency is nearly 100% after agitation for 5 min. In order to study the suspension behavior of PM2.5 in solvents, a Brookhaven ZetaPlus Particle Size Analyzer was used to determine the particle size distribution and suspension behavior of air particulates in the solvent. The pre-digestion and modification effect of nitric acid would be discussed. Palladium was added as a chemical modifier and the temperature program of ETAAS was changed in order to improve the recovery. The slurry was introduced directly into a graphite tube for atomization. The metal content in the sample was determined by the standard addition method. In addition, a conventional acid digestion procedure was applied to verify the efficiency of the slurry sampling method. It offers a quick and efficient alternative method for heavy metal characterization in fine particulates.

  12. Determination of palladium by graphite furnace atomic absorption spectroscopy without matrix matching.

    Science.gov (United States)

    Jia, X; Wang, T; Wu, J

    2001-05-30

    A graphite furnace atomic absorption spectroscopy method for the analysis of the palladium (Pd) content in bulk pharmaceutical drug substances and their intermediates prepared in aqueous solutions is extended to samples prepared in acetonitrile (ACN) and ACN-water mixtures as well to samples prepared in dimethyl sulfoxide (DMSO) and DMSO-water mixtures. The Pd content in samples solubilized in these solvents can be accurately determined with calibration established with standards prepared in aqueous solutions without matrix matching or using the method of standard additions. The validity of this method is demonstrated by spike recovery studies and by the agreement with results for the same samples prepared in these solvents, in concentrated nitric acid, and prepared by a microwave digestion system.

  13. Determination of calcium, magnesium and zinc in unused lubricating oils by atomic absorption spectroscopy.

    Science.gov (United States)

    Udoh, A P

    1995-12-01

    Varying concentrations of lanthanum and strontium were added to solutions of ashed unused lubricating oils for the determination of calcium, magnesium and zinc content using flame atomic absorption spectrophotometry. At least 3000 mug g(-1) of lanthanum or strontium was required to completely overcome the interference of the phosphate ion, PO(3-)(4), and give peak values for calcium. The presence of lanthanum or strontium did not cause an appreciable increase in the amount of magnesium and zinc obtained from the analyses. The method is fast and reproducible, and the coefficients of variation calculated for the elements using one of the samples were 1.6% for calcium, 3.5% for magnesium and 0.2% for zinc. Results obtained by this method were better than those obtained by other methods for the same samples.

  14. [Determination of inorganic elements in different parts of Sonchus oleraceus L by flame atomic absorption spectrometry].

    Science.gov (United States)

    Wang, Nai-Xing; Cui, Xue-Gui; Du, Ai-Qin; Mao, Hong-Zhi

    2007-06-01

    Flame atomic absorption spectrometry with air-acetylene flame was used for the determination of inorganic metal elements in different parts ( flower, leaf, stem and root) of Sonchus oleraceus L. The contents of Ca, Mg, K, Na, Fe, Mn, Cu, Zn, Cr, Co, Ni, Pb and Cd in the flower, leaf, stem and root of Sonchus oleraceus L were compared. The order from high to low of the additive weight (microg x g(-1)) for the 13 kinds of metal elements is as follows: leaf (77 213.72) > flower (47 927.15) > stem(42 280.99) > root (28 131.18). From the experimental results it was found that there were considerable differences in the contents of the metal elements in different parts, and there were richer contents of Fe, Zn, Mn and Cu in root and flower, which are necessary to human health, than in other parts.

  15. Determination of barium in bottled drinking water by graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Fagioli, F.; Locatelli, C.; Lanciotti, E.; Vallone, G.; Mazzotta, D.; Mugelli, A.

    1988-11-01

    In relation to the wide environmental spread of barium and to its cardiovascular effects, barium levels were determined by graphite furnace atomic absorption spectrometry in 60 different brands of bottled water marketed in Italy. Matrix interferences were investigated in order to evaluate the use of an analytical calibration function rather than the much more time consuming addition technique. The barium content ranged from limit of detection C/sub L/ (7.0 ..mu..g/1) up to 660 ..mu..g/1, the median value being 80 ..mu..g/l, while the recovery tests varied between 90 and 110% and the precision of the method (s/sub yx/) was 2.5%.

  16. Determination of some antihistaminic drugs by atomic absorption spectrometry and colorimetric methods.

    Science.gov (United States)

    El-Kousy, N; Bebawy, L I

    1999-08-01

    Atomic absorption spectrometry (AAS) and colourimetric methods have been developed for the determination of pizotifen (I), ketotifen (II) and loratadine (III). The first method depends on the reaction of the three drugs (I); (II) and (III) with cobalt thiocyanate reagent at pH 2 to give ternary complexes. These complexes are readily extracted with organic solvent and estimated by indirect atomic absorption method via the determination of the cobalt content in the formed complex after extraction in 0.1 M hydrochloric acid. It was found that the three drugs can be determined in the concentration ranges from 10 to 74, 12 to 95 and 10 to 93 microg ml(-1) with mean percentage recovery of 99.71+/-0.87, 99.70+/-0.79 and 99.62+/-0.75%, respectively. The second method is based on the formation of orange red ion pairs as a result of the reaction between (I); (II) and (III) and molybdenum thiocyanate with maximum absorption at 469.5 nm in dichloromethane. Appropriate conditions were established for the colour reaction. Under the proposed conditions linearity was obeyed in the concentration ranges 3.5-25, 5-37.5 and 2.5-22.5 microg ml(-1) with mean percentage recovery of 99.60+/-0.41, 100.11+/-0.43 and 99.31+/-0.47% for (I): (II) and (III), respectively. The third method depends on the formation of radical ion using 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ). The colour formed was measured at 588 nm for the three drugs (I); (II) and (III), respectively. The method is valid in concentration range 10-80 microg ml(-1) with mean percentage recovery 99.75+/-0.44, 99.94+/-0.72 and 99.17+/-0.36% for (I); (II) and (III), respectively. The proposed methods were applied to the analysis of pharmaceutical preparations. The results obtained were statistically analysed and compared with those obtained by applying the official and reference methods.

  17. Cadmium, copper, lead, and zinc determination in precipitation: A comparison of inductively coupled plasma atomic emission spectrometry and graphite furnace atomization atomic absorption spectrometry

    Science.gov (United States)

    Reddy, M.M.; Benefiel, M.A.; Claassen, H.C.

    1987-01-01

    Selected trace element analysis for cadmium, copper, lead, and zinc in precipitation samples by inductively coupled plasma atomic emission Spectrometry (ICP) and by atomic absorption spectrometry with graphite furnace atomization (AAGF) have been evaluated. This task was conducted in conjunction with a longterm study of precipitation chemistry at high altitude sites located in remote areas of the southwestern United States. Coefficients of variation and recovery values were determined for a standard reference water sample for all metals examined for both techniques. At concentration levels less than 10 micrograms per liter AAGF analyses exhibited better precision and accuracy than ICP. Both methods appear to offer the potential for cost-effective analysis of trace metal ions in precipitation. ?? 1987 Springer-Verlag.

  18. Determination of mercury in hair: Comparison between gold amalgamation-atomic absorption spectrometry and mass spectrometry.

    Science.gov (United States)

    Domanico, Francesco; Forte, Giovanni; Majorani, Costanza; Senofonte, Oreste; Petrucci, Francesco; Pezzi, Vincenzo; Alimonti, Alessandro

    2016-09-29

    Mercury is a heavy metal that causes serious health problems in exposed subjects. The most toxic form, i.e., methylmercury (MeHg), is mostly excreted through human hair. Numerous analytical methods are available for total Hg analysis in human hair, including cold vapour atomic fluorescence spectrometry (CV-AFS), inductively coupled plasma mass spectrometry (ICP-MS) and thermal decomposition amalgamation atomic absorption spectrometry (TDA-AAS). The aim of the study was to compare the TDA-AAS with the ICP-MS in the Hg quantification in human hair. After the washing procedure to minimize the external contamination, from each hair sample two aliquots were taken; the first was used for direct analysis of Hg by TDA-AAS and the second was digested for Hg determination by the ICP-MS. Results indicated that the two data sets were fully comparable (median; TDA-AAS, 475ngg(-1); ICP-MS, 437ngg(-1)) and were not statistically different (Mann-Whitney test; p=0.44). The two techniques presented results with a good coefficient of correlation (r=0.94) despite different operative ranges and method limits. Both techniques satisfied internal performance requirements and the parameters for method validation resulting sensitive, precise and reliable. Finally, the use of the TDA-AAS can be considered instead of the ICP-MS in hair analysis in order to reduce sample manipulation with minor risk of contamination, less time consuming due to the absence of the digestion step and cheaper analyses.

  19. Determination of selenium in human spermatozoa and prostasomes using base digestion and electrothermal atomic absorption spectrophotometry.

    Science.gov (United States)

    Suistomaa, U; Saaranen, M; Vanha-Perttula, T

    1987-10-15

    A method for the determination of selenium in human spermatozoa and prostasomes is described. The samples were digested with 25% (w/v) tetramethylammonium hydroxide (TMAH) in methanol and analyzed by atomic absorption spectrometry with electrothermal atomization and Zeeman background correction (ET-AAS). Nickel was used as a matrix modifier. Calibration was performed using the matrix-based calibration curve. The TMAH-digestion method agreed well with a conventional digestion procedure using concentrated nitric acid. The TMAH-digestion does not require heating or strong acids and it was suitable for small biological samples. The average recovery of added selenium in spermatozoan digests was 95.1 +/- 5.2% (n = 5). The coefficient of variation was 9.1% (n = 21). The accuracy of the method tested with the NBS standard 1577 (bovine liver, certified at 1.1 +/- 0.1 micrograms Se/g) resulted in a value of 0.98 +/- 0.10 micrograms Se/g (n = 16). The method was further tested in an interlaboratory comparison study.

  20. Determination of nickel in active pharmaceutical ingredients by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Bubnič, Zoran; Urleb, Uroš; Kreft, Katjuša; Veber, Marjan

    2010-03-01

    An electrothermal atomic absorption spectrometric procedure for the determination of nickel in active pharmaceutical ingredients was developed. Since the recoveries of nickel by the direct dissolution of samples in diluted nitric acid were low and caused errors in the determination of Ni in pharmaceutical samples, different approaches for sample pre-treatment were examined. It was found that the microwave digestion was the most suitable way for sample preparation. Various combinations of digestion agents and different microwave conditions were tested. The combination of nitric acid and hydrogen peroxide was found to be the most appropriate. The validity of the method was evaluated by recovery studies of spiked samples and by the comparison of the results obtained by inductively coupled plasma mass spectrometry (ICP-MS). The recovery ranged from 87.5 to 104.0% and a good agreement was achieved between both methods. The detection limit and the limit of quantification were 0.6 and 2.1 µg g-1 respectively. The precision of the method was confirmed by the determination of Ni in the spiked samples and was below 4%, expressed in terms of a relative standard deviation. The method was applied to the determination of nickel in production samples of active pharmaceutical ingredients and intermediates.

  1. Determination of iron in natural and mineral waters by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    ROLANDAS KAZLAUSKAS

    2004-05-01

    Full Text Available Simple methods for the determination of Fe in natural and mineral waters by flame atomic absorption spectrometry (AAS are suggested. The results of the investigation of selectivity of the proposed AAS method proved that this procedure is not affected by high concentrations of other metals. The calibration graph for iron was linear at levels near the detection limit up to at least 0.10 mg ml-1. For the determination of microamounts of iron in mineral waters, an extraction AAS technique was developed. Iron was retained as Fe-8-oxyquinoline complex and extracted into chloroform. The optimal conditions for the extraction of the iron complex were determined. The AAS method was applied to the determination of Fe in mineral waters and natural waters from different areas of Lithuania. The accuracy of the developed method was sufficient and evaluated in comparison with a photometric method. The obtained results demonstrated that the procedure could be successfully applied for the analysis of water samples with satisfactory accuracy.

  2. Direct determination of arsenic in petroleum derivatives by graphite furnace atomic absorption spectrometry: A comparison between filter and platform atomizers

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Emilene; Rampazzo, Roger T.; Dessuy, Morgana B. [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil); Vale, Maria Goreti R., E-mail: mgrvale@ufrgs.br [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq - INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Silva, Marcia M. da [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil); Welz, Bernhard [Instituto Nacional de Ciencia e Tecnologia do CNPq - INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Katskov, Dmitri A. [Tshwane University of Technology (TUT), Faculty of Science, Chemistry Department, Pretoria 0001 (South Africa)

    2011-05-15

    In the present work a direct method for the determination of arsenic in petroleum derivatives has been developed, comparing the performance of a commercial transversely heated platform atomizer (THPA) with that of a transversely heated filter atomizer (THFA). The THFA results in a reduction of background absorption and an improved sensitivity as has been reported earlier for this atomizer. The mixture of 0.1% (m/v) Pd + 0.03% (m/v) Mg + 0.05% (v/v) Triton X-100 was used as the chemical modifier for both atomizers. The samples (naphtha, gasoline and petroleum condensate) were stabilized in the form of a three-component solution (detergentless microemulsion) with the sample, propan-1-ol and 0.1% (v/v) HNO{sub 3} in a ratio of 3.0:6.4:0.6. The characteristic mass of 13 pg found in the THFA was about a factor of two better than that of 28 pg obtained with the THPA; however, the limits of detection (LOD) and quantification (LOQ) were essentially the same for both atomizers (1.9 and 6.2 {mu}g L{sup -1}, respectively, for THPA, and 1.8 and 5.9 {mu}g L{sup -1}, respectively, for THFA) due to the increased noise observed with the THFA. A possible explanation for that is a partial blockage of the radiation from the hollow cathode lamp by the narrow inner diameter of this tube and the associated loss of radiation energy. Due to the lack of an appropriate certified reference material, recovery tests were carried out with inorganic and organic arsenic standards and the results were between 89% and 111%. The only advantage of the THFA found in this work was a reduction of the total analysis time by about 20% due to the 'hot injection' that could be realized with this furnace. The arsenic concentrations varied from < LOQ to 43.3 {mu}g L{sup -1} in the samples analyzed in this work.

  3. Determination of trace impurities in titanium dioxide by direct solid sampling electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Docekal, Bohumil [Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic, Veveri 97, CZ-61142, Brno (Czech Republic)], E-mail: docekal@iach.cz; Vojtkova, Blanka [Institute of Materials Science, Faculty of Chemistry, Brno University of Technology, Purkynova 118, CZ-61200 Brno (Czech Republic)

    2007-03-15

    A true direct solid sampling electrothermal atomic absorption spectrometry method with Zeeman-effect background correction (Analytik Jena ZEEnit 60 AAS) was developed for the determination of As, Cd, Hg, Pb, Sb and Zn in powdered titanium dioxide of pharmaceutical, food and cosmetics grade. The interaction of the titanium matrix and graphite surface of the sample carrier boat in a transversely heated graphite tube atomizer was investigated. Conversion of titanium dioxide to interfering TiO{sub 2}-TiC-liquid phase, running out the sampling boat, was observed at temperatures above 2000 deg. C. The temperature program was optimized accordingly for these volatile analytes in atomization and cleaning steps in order to prevent this interference and to prolong significantly the analytical lifetime of the boat to more than one thousand runs. For all elements, calibration by aqueous standard addition method, by wet-chemically analyzed samples with different content of analytes and/or by dosing one sample in different amounts, were proved as adequate quantification procedures. Linear dynamic calibration working ranges can be considerably expanded up to two orders of magnitude within one measurement run by applying three-field dynamic mode of the Zeeman background correction system. The results obtained by true direct solid sampling technique are compared with those of other independent, mostly wet-chemical methods. Very low limits of detection (3{sigma} criterion) of true solid sampling technique of 21, 0.27, 24, 3.9, 6.3 and 0.9 ng g{sup -1} were achieved for As, Cd, Hg, Pb, Sb and Zn, respectively.

  4. [The determination of chromium in feeds by flame atomic absorption spectrophotometry].

    Science.gov (United States)

    Wang, Jian; Jia, Bin; Guo, Li-ping; Lin, Qiu-ping

    2005-07-01

    Chromium in feeds is regulated by China Standard GB 13078-2001. A method of flame atomic absorption spectrophotometry for the determination of Cr in feeds has been developed in allusion to shortage of China standard method. Several acetylene flow-rate, burner-high and the additive of interference suppressor NH4Cl were studied respectively on the effect of sensitivities of Cr(III) and Cr(VI). The two sets analytical average results of Cr in feed sample determined by calibration curves of Cr(III) and Cr(VI) were tested by t test, no marked discrepancy was found. Optimum instrumental conditions of Cr(III) and Cr(VI) with same sensitivity were confirmed. Sensitivity was 0.014 microg x mL(-1) with detection limit 0.70 mg x kg(-1). The recoveries were 94.4%-104.9%. Relative standard deviation of sample determination (5-6 times) was 1.90%-4.08%. This method is simply, fast and exact, the detection limit was answered for Cr limit in feeds regulated by GB 13078-2001, it can be applied to the analysis of Cr in feeds.

  5. Determination of Anionic Surfactants Using Atomic Absorption Spectrometry and Anodic Stripping Voltammetry

    Science.gov (United States)

    John, Richard; Lord, Daniel

    1999-09-01

    An experiment has been developed for our undergraduate analytical chemistry course that demonstrates the indirect analysis of anionic surfactants by techniques normally associated with metal ion determination; that is, atomic absorption spectroscopy (AAS) and anodic stripping voltammetry (ASV). The method involves the formation of an extractable complex between the synthetic surfactant anion and the bis(ethylenediamine)diaqua copper(II) cation. This complex is extracted into chloroform and then back-extracted into dilute acid. The resulting Cu(II) ions are determined by AAS and ASV. Students are required to determine the concentration of a pre-prepared "unknown" anionic surfactant solution and to collect and analyze a real sample of their choice. After the two extraction processes, students typically obtain close to 100% analytical recovery. Correlation between student AAS and ASV results is very good, indicating that any errors that occur probably result from their technique (dilutions, extractions, preparation of standards, etc.) rather than from the end analyses. The experiment is a valuable demonstration of the following analytical principles: indirect analysis; compleximetric analysis; liquid-liquid (solvent) extraction; back-extraction (into dilute acid); analytical recovery; and metal ion analysis using flame-AAS and ASV.

  6. Simultaneous determination of cadmium and lead in wine by electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Freschi, Gian P. G.; Dakuzaku, Carolina S.; de Moraes, Mercedes; Nóbrega, Joaquim A.; Gomes Neto, José A.

    2001-10-01

    A method has been developed for the direct simultaneous determination of Cd and Pb in white and red wine by electrothermal atomic absorption spectrometry (ET-AAS) using a transversely heated graphite tube atomizer (THGA) with longitudinal Zeeman-effect background correction. The thermal behavior of both analytes during pyrolysis and atomization stages were investigated in 0.028 mol l -1 HNO 3 and in 1+1 v/v diluted wine using mixtures of Pd(NO 3) 2+Mg(NO 3) 2 and NH 4H 2PO 4+Mg(NO 3) 2 as chemical modifiers. With 5 μg Pd+3 μg Mg as the modifiers and a two-step pyrolysis (10 s at 400°C and 10 s at 600°C), the formation of carbonaceous residues inside the atomizer was avoided. For 20 μl of sample (wine+0.056 mol l -1 HNO 3, 1+1, v/v) dispensed into the graphite tube, analytical curves in the 0.10-1.0 μg l -1 Cd and 5.0-50 μg l -1 Pb ranges were established. The characteristic mass was approximately 0.6 pg for Cd and 33 pg for Pb, and the lifetime of the tube was approximately 400 firings. The limits of detection (LOD) based on integrated absorbance (0.03 μg l -1 for Cd, 0.8 μg l -1 for Pb) exceeded the requirements of Brazilian Food Regulations (decree #55871 from Health Department), which establish the maximum permissible level for Cd at 200 μg l -1 and for Pb at 500 μg l -1. The relative standard deviations ( n=12) were typically wine samples varied from 88 to 107% and 93 to 103%, respectively. The accuracy of the direct determination of Cd and Pb was checked for 10 table wines by comparing the results with those obtained for digested wine using single-element ET-AAS, which were in agreement at the 95% confidence level.

  7. Comparisons of selected methods for the determination of kinetic parameters from electrothermal atomic absorption data

    Science.gov (United States)

    Fonseca, Rodney W.; Pfefferkorn, Lisa L.; Holcombe, James A.

    1994-12-01

    Three of the methods available for the determination of kinetic parameters for atom formation in ETAAS were compared. In the approach of mcnally and holcombe [ Anal. Chem. 59, 1015 (1987)], Arrhenius-type plots are used to extract activation energy values while an approximation of the order of release is obtained by studying the alignment of the absorption maxima at increasing analyte concentrations. In the method of rojas and olivares [ Spectrochim. Acta47B, 387 (1992)], plots are prepared for different orders of release, with the correct order yielding a longer linear region from whose slope the activation energy is calculated. The method of yan et al. [ Spectrochim. Acta48B, 605 (1993)] uses a single absorption profile for the calculations. Activation energy and the order of release are obtained from the slope and intercept, respectively, on their graph. All three methods assume linear heating rate, constant activation energies, and furnace isothermality. The methods were tested with the same experimental data sets for Cu, Au and Ni using a spatially isothermal cuvette. Since intensive mathematical treatments commonly have deleterious effects on the uncertainty of the final result, the methods were compared using both the original data and a smoothed version of it. In general, the three methods yielded comparable results for the metals studied. However, choosing the most linear plot to determine the correct order of release when using Rojas and Olivares' method was sometimes subjective, and McNally and Holcombe's method provided only estimates for the orders of release that were neither zero nor unity.

  8. Determination of Inorganic Arsenic Species by Electrochemical Hydride Generation Atomic Absorption Spectrometry with Selective Electrochemical Reduction

    Institute of Scientific and Technical Information of China (English)

    LI Xun; WANG Zheng-Hao

    2007-01-01

    A new direct procedure for the determination of inorganic arsenic species was developed by electrochemical hydride generation atomic absorption spectrometry (EcHG-AAS) with selective electrochemical reduction. The determination of inorganic arsenic species is based on the fact that As(Ⅲ) shows significantly higher absorbance at low electrolytic currents than As(Ⅴ) in 0.3 mol·L-1 H2SO4.The electrolytic current used for the determination of As(Ⅲ) without considerable interferences of As(V) was 0.4 A, whereas the current for the determination of As(Ⅲ)and As(V) was 1.2 A. For equal concentrations of As(Ⅲ) and As(V) in a sample, the interferences of As(V) during the As(Ⅲ) determination were smaller than 5%. The absorbance for As(V) could be calculated by subtracting that for As(Ⅲ) measured at 0.4 A from the total absorbance for As(Ⅲ) and As(V) measured at 1.2 A, and then the concentration of As(V) can be obtained by its calibration curve at 1.2 A. The methodology developed provided the detection limits of 0.3 and 0.6 ng·ml-1 for As(Ⅲ) and As(V) respectively.The relative standrad deviations were of 3.5% for 20 ng·ml-1 As(Ⅲ) and 302% for 20 ng·ml-1 As(V).The method was successfully applied to determination of soluble inorganic arsenic species in Chinese medicine.

  9. Determination of firing distance. Lead analysis on the target by atomic absorption spectroscopy (AAS).

    Science.gov (United States)

    Gagliano-Candela, Roberto; Colucci, Anna P; Napoli, Salvatore

    2008-03-01

    This paper reports a method for the determination of the firing distance. Atomic absorption spectroscopy (AAS) was used to determine the lead (Pb) pattern around bullet holes produced by shots on test targets from the gun. Test shots were made with a Colt 38 Special at 5, 10, 20, 25, 30, 35, 40, 45, 50, 60, 80, and 100 cm target distance. The target was created with sheets of Whatman no. 1 paper on a polystyrene support. The target was subdivided into three carefully cut out rings (1, 2, and 3; with external diameters of 1.4 cm; 5 cm; 10.2 cm, respectively). Each sample was analyzed with graphite furnace AAS. Lead values analysis performed for each ring yielded a linear relation between the firing distance (cm) and the logarithm of lead amounts (microg/cm(2)) in definite target areas (areas 2 + 3): [ln dPb(2+3) = a(0) + a(1)l]; where dPb(2+3) = lead microg/cm(2) of area 2 + 3; a(0) and a(1) are experimentally calculated; l = distance in cm.

  10. An indirect atomic absorption spectrometric determination of ciprofloxacin, amoxycillin and diclofenac sodium in pharmaceutical formulations

    Directory of Open Access Journals (Sweden)

    MAHMOUD MOHAMED ISSA

    2008-05-01

    Full Text Available A highly sensitive indirect atomic absorption spectrophotometric (AAS method has been developed for the determination of very low concentrations of ciprofloxacin, amoxycillin and diclofenac sodium. The method is based on the oxidation of these drugs with iron(III. The excess of iron(III was extracted into diethyl ether and then the iron(II in the aqueous layer was aspirated into an air–acetylene flame and determined by AAS. The linear concentration ranges were 25–400, 50–500 and 60–600 ng ml-1 for ciprofloxacin, amoxycillin and diclofenac sodium, respectively. The results were statistically compared with the official method using t- and f-test at p < 0.05. There were insignificant interferences from most of the excipients present. The intra- and inter-day assay coefficients of variation were less than 6.1 % and the recoveries ranged from 95 to 103 %. The method was applied for the analysis of these drug substances in their commercial pharmaceutical formulations.

  11. Determination of copper in powdered chocolate samples by slurry-sampling flame atomic-absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Walter N.L. dos; Silva, Erik G.P. da; Fernandes, Marcelo S.; Araujo, Rennan G.O.; Costa, Anto' ' enio C.S.; Ferreira, Sergio L.C. [Nucleo de Excelencia em Quimica Analitica da Bahia, Universidade Federal da Bahia, Instituto de Quimica, Salvador, Bahia (Brazil); Vale, M.G.R. [Instituto de Quimica, Universidade Federal da Bahia do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul (Brazil)

    2005-06-01

    Chocolate is a complex sample with a high content of organic compounds and its analysis generally involves digestion procedures that might include the risk of losses and/or contamination. The determination of copper in chocolate is important because copper compounds are extensively used as fungicides in the farming of cocoa. In this paper, a slurry-sampling flame atomic-absorption spectrometric method is proposed for determination of copper in powdered chocolate samples. Optimization was carried out using univariate methodology involving the variables nature and concentration of the acid solution for slurry preparation, sonication time, and sample mass. The recommended conditions include a sample mass of 0.2 g, 2.0 mol L{sup -1} hydrochloric acid solution, and a sonication time of 15 min. The calibration curve was prepared using aqueous copper standards in 2.0 mol L{sup -1} hydrochloric acid. This method allowed determination of copper in chocolate with a detection limit of 0.4 {mu}g g{sup -1} and precision, expressed as relative standard deviation (RSD), of 2.5% (n=10) for a copper content of approximately 30 {mu}g g{sup -1}, using a chocolate mass of 0.2 g. The accuracy was confirmed by analyzing the certified reference materials NIST SRM 1568a rice flour and NIES CRM 10-b rice flour. The proposed method was used for determination of copper in three powdered chocolate samples, the copper content of which varied between 26.6 and 31.5 {mu}g g{sup -1}. The results showed no significant differences with those obtained after complete digestion, using a t-test for comparison. (orig.)

  12. Determination of arsenic in a nickel alloy by flow injection hydride generation atomic absorption spectrometry

    Science.gov (United States)

    Hanna, C. P.; Tyson, J. F.; Offley, S. G.

    1992-08-01

    The development of a method for the direct determination of trace arsenic quantities in nickel alloy digests, by flow injection hydride generation atomic absorption spectrometry, is described. An optimization study of the manifold and chemical parameters produced system performance, in terms of tolerance of the nickel matrix and sensitivity, such that matrix removal and pre-reduction of As(V) to As (III) prior to arsine generation were eliminated. Full recovery of the As(V) signal from a solution containing 5 ng ml -1 in the presence of 60 μg ml -1 nickel was obtained. Validation of the method was achieved by analyzing a British Chemical Standard (BCS) Certified Reference Material (CRM) #346 IN nickel alloy containing arsenic at a concentration of 50 μg g -1. Following dissolution in nitric and hydrofluoric acids by a microwave assisted procedure, the only subsequent preparation required was dilution by the appropriate factor. Up to 60 injections h -1 may be made, with a detection limit of 0.5 ng ml -1 arsenic (250 pg absolute) as As(V) in a 500 μl sample. The peak height characteristic concentration is 0.46 ng ml -1, with a relative standard deviation of 3.5% for a 10 ng ml -1 As(V) standard ( n = 6).

  13. [Determination of thirteen metal elements in the plant Foeniculum vulgare Mill. by flame atomic absorption spectrophotometry].

    Science.gov (United States)

    Xue, Guo-qing; Liu, Qing; Han, Yu-qi; Wei, Hui-guang; Dong, Ting

    2006-10-01

    The objective of the paper is to determine the amount of metal elements of Na, K, Mg, Ca, Cu, Zn, Mn, Fe, Co, Ni, Cd, Cr and Pb in the planted Foeniculum vulgare Mill. by flame atomic absorption spectrophotometry (FAAS), after the cinefaction and the digestion with HNO3-HClO4 (phi 4:1) at 90-95 degrees C and normal pressure. The optimum parameters of FAAS and the effects of solution medium on the results were investigated. The analytical results show that the amount of Na, K, Mg, Ca, Mn, Fe, Cu, Zn and Pb was 1508.7, 27653.0, 2036.0, 4848.1, 24.8, 323.5, 15.2, 23.7 and 10.8 microg x g(-1), respectively, and that of Co, Ni, Cd and Cr was not checked out in the samples. The recovery of standard addition is 97.45%-102.50%, the relative standard deviation (n=9) was 0.34%-2.77%. The characteristic method is quick, simple and convenient and the results are satisfactory.

  14. [Determination of trace elements in new food sources by flame atomic absorption spectrophotometry].

    Science.gov (United States)

    Liu, Li E; Ding, Li; Qi, Min; Han, Xiu Li; Zhang, Hong-Quan

    2007-07-01

    Samples were digested by HNO3 + HClO4. Flame atomic absorption spectrophotometry (FAAS) was successfully used to determine copper, zinc and iron in new resource food. Under our experimental conditions, the recovery ratio was 94.66%-108.80%; the precision was 0.71%-4.78%. This method of measuring elements is convenient, rapid and accurate. The results showed that there are profitable elements, such as copper, zinc and iron in new resourse food in Henan province. By F test and SNK test, the content sequence of metal elements was found as follows: copper, Chrysanthemum morifolium Ramat = Silkworm pupa > flowers of Pueraria lobata Ohwin = Wheat germ = Codonopsis lanceolata = roots of Pueraria lobata Ohwi > Opuntia dillenii Haw. Zinc, Opuntia dillenii Haw > Silkworm pupa = flowers of Pueraria lobata Ohwi = roots of Pueraria lobata Ohwi = Wheat germ = Codonopsis lanceolata = Chrysanthemum morifolium Ramat. Iron, Silkworm pupa = C hrysanthemum morifolium Ramat = roots of Pueraria lobata Ohwi > flowers of Pueraria lobata Ohwi = Wheat germ = Codonopis lanceolata = Opuntia dillenii Haw.

  15. Influence of phosphorus and calcium on flame atomic absorption spectrophotometric determination of lead in canned fish products.

    Science.gov (United States)

    Serra, T M; Serrano, J F

    1984-01-01

    Lead was determined in the presence of whole multiples of the P/Ca ratio found in Portuguese canned fish by flame atomic absorption spectrophotometry with and without using an ashing aid. Under our experimental conditions, use of the ashing aid eliminates P and Ca interference. Results with real samples, spiked with 1, 2, 3, and 4 ppm lead, are presented and statistically treated.

  16. A COMPARISON OF A SPECTROPHOTOMETRIC (QUERCETIN) METHOD AND AN ATOMIC-ABSORPTION METHOD FOR DETERMINATION OF TIN IN FOOD

    DEFF Research Database (Denmark)

    Engberg, Å

    1973-01-01

    Procedures for the determination of tin in food, which involve a spectrophotometric method (with the quercetin-tin complex) and an atomic-absorption method, are described. The precision of the complete methods and of the individual analytical steps required is evaluated, and the parameters...

  17. Determination of nickel by flame atomic-absorption spectrophotometry after separation by adsorption of its nioxime complex on microcrystalline naphthalene.

    Science.gov (United States)

    Nagahiro, T; Puri, B K; Katyal, M; Satake, M

    1984-11-01

    A method has been developed for the determination of nickel in alloys by flame atomic-absorption spectrophotometry after formation of a water-insoluble complex, its adsorption on microcrystalline naphthalene, and dissolution of the complex and naphthalene in nitric acid and xylene.

  18. Determination of mercury in phosphate fertilizers by cold vapor atomic absorption spectrometry.

    Science.gov (United States)

    de Jesus, Robson M; Silva, Laiana O B; Castro, Jacira T; de Azevedo Neto, Andre D; de Jesus, Raildo M; Ferreira, Sergio L C

    2013-03-15

    In this paper, a method for the determination of mercury in phosphate fertilizers using slurry sampling and cold vapor atomic absorption spectrometry (CV QT AAS) is proposed. Because mercury (II) ions form strong complexes with phosphor compounds, the formation of metallic mercury vapor requires the presence of lanthanum chloride as a release agent. Thiourea increases the amount of mercury that is extracted from the solid sample to the liquid phase of the slurry. The method is established using two steps. First, the slurry is prepared using the sample, lanthanum chloride, hydrochloric acid solution and thiourea solution and is sonicated for 20 min. Afterward, mercury vapor is generated using an aliquot of the slurry in the presence of the hydrochloric acid solution and isoamylic alcohol with sodium tetrahydroborate solution as the reducing agent. The experimental conditions for slurry preparation were optimized using two-level full factorial design involving the factors: thiourea and lanthanum chloride concentrations and the duration of sonication. The method allows the determination of mercury by external calibration using aqueous standards with limits of detection and quantification of 2.4 and 8.2 μg kg(-1), respectively, and precision, expressed as relative standard deviation, of 6.36 and 5.81% for two phosphate fertilizer samples with mercury concentrations of 0.24 and 0.57 mg kg(-1), respectively. The accuracy was confirmed by the analysis of a certified reference material of phosphate fertilizer that was provided by the National Institute of Standards & Technology (NIST). The method was applied to determine mercury in six commercial samples of phosphate fertilizers. The mercury content varied from 33.97 to 209.28 μg kg(-1). These samples were also analyzed employing inductively coupled plasma mass spectrometry (ICP-MS). The ICP-MS results were consistent with the results from our proposed method.

  19. Chemical modifiers in arsenic determination in biological materials by tungsten coil electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bruhn, C.G.; Huerta, V.N.; Neira, J.Y. [Departamento de Analisis Instrumental, Facultad de Farmacia, Universidad de Concepcion, P.O. Box 237, Concepcion (Chile)

    2004-01-01

    Palladium, iridium, and rhodium are evaluated as possible chemical modifiers in the determination of As in digest solutions of biological materials (human hair and clam) by tungsten coil electrothermal atomic absorption spectrophotometry (TCA-AAS). The modifier in solution was applied onto the coil and thermally pre-reduced; the pre-reduction conditions, the amount of modifier, and the thermal program were optimized. Palladium was not satisfactory, whereas Ir and Rh were effective modifiers and rendered better relative sensitivity for As by a factor of 1.4 and 1.9, respectively compared to the case without modifier. Upon optimization of thermal conditions for As in pre-reduced Ir (2.0 {mu}g) and Rh (2.0 {mu}g) modifiers and in the digest solutions of the study matrices, Rh (2.0 {mu}g) was more effective modifier and was selected as such. The mean within-day repeatability was 2.8% in consecutive measurements (25-100 {mu}g L{sup -1}) (3 cycles, each of n=6) and confirmed good short-term stability of the absorbance measurements. The mean reproducibility was 4.4% (n=20 in a 3-day period) and the detection limit (3{sigma}{sub blank}/slope) was 29 pg (n=15). The useful coil lifetime in Rh modifier was extended to 300-400 firings. Validation was by determination of As in the certified reference material (CRM) of ''Oyster tissue'' solution with a percentage relative error (E{sub rel}%) of 2% and percentage relative standard deviation (RSD%) of 3% (n=4), and by analytical recovery of As spiked in CRM of human hair [94{+-}8% (n=4)]. The methodology is simple, fast (sample readout frequency 21 h{sup -1}), reliable, of low cost, and was applied to the determination of As in hair samples of exposed and unexposed workers. (orig.)

  20. Determination of arsenic and cadmium in crude oil by direct sampling graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, Alexandre de; Zmozinski, Ariane Vanessa [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Damin, Isabel Cristina Ferreira [Faculdade Dom Bosco de Porto Alegre, 90520-280, Porto Alegre, RS (Brazil); Silva, Marcia Messias, E-mail: mmsilva@iq.ufrgs.br [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil); Vale, Maria Goreti Rodrigues [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil)

    2012-05-15

    In this work, a direct sampling graphite furnace atomic absorption spectrometry method has been developed for the determination of arsenic and cadmium in crude oil samples. The samples were weighed directly on the solid sampling platforms and introduced into the graphite tube for analysis. The chemical modifier used for both analytes was a mixture of 0.1% Pd + 0.06% Mg + 0.06% Triton X-100. Pyrolysis and atomization curves were obtained for both analytes using standards and samples. Calibration curves with aqueous standards could be used for both analytes. The limits of detection obtained were 5.1 {mu}g kg{sup -1} for arsenic and 0.2 {mu}g kg{sup -1} for cadmium, calculated for the maximum amount of sample that can be analyzed (8 mg and 10 mg) for arsenic and cadmium, respectively. Relative standard deviations lower than 20% were obtained. For validation purposes, a calibration curve was constructed with the SRM 1634c and aqueous standards for arsenic and the results obtained for several crude oil samples were in agreement according to paired t-test. The result obtained for the determination of arsenic in the SRM against aqueous standards was also in agreement with the certificate value. As there is no crude oil or similar reference material available with a certified value for cadmium, a digestion in an open vessel under reflux using a 'cold finger' was adopted for validation purposes. The use of paired t-test showed that the results obtained by direct sampling and digestion were in agreement at a 95% confidence level. Recovery tests were carried out with inorganic and organic standards and the results were between 88% and 109%. The proposed method is simple, fast and reliable, being appropriated for routine analysis. - Highlights: Black-Right-Pointing-Pointer A direct sampling GF AAS method to determine As and Cd in crude oil was proposed. Black-Right-Pointing-Pointer The conventional chemical modifier Pd/Mg has been used to stabilize As and Cd. Black

  1. Slurry sampling techniques for the determination of lead in Bangladeshi fish samples by electrothermal atomic absorption spectrometry with a metal tube atomizer.

    Science.gov (United States)

    Rahman, Mohammad Arifur; Kaneco, Satoshi; Suzuki, Tohru; Katsumata, Hideyuki; Ohta, Kiyohisa

    2005-05-01

    Ultrasonic slurry sampling electrothermal atomic absorption spectrometry with a metal tube atomizer has been applied to the determination of lead in Bangladeshi fish samples. The slurry sampling conditions, such as slurry stabilizing agent, slurry concentration, pyrolysis temperature for the slurried fish samples, particle size and ultrasonic agitation time, were optimized for electrothermal atomic absorption spectrometry with the Mo tube atomizer. Thiourea was used as the chemical modifier for the interference of matrix elements. The detection limit was 53 fg (3S/N). The determined amount of lead in Bangladeshi fish samples was consistent with those measured in the dissolved acid-digested samples. The advantages of the proposed methods are easy calibration, simplicity, low cost and rapid analysis.

  2. Atomic absorption techniques for determining vanadium and nickel in crude oil

    Energy Technology Data Exchange (ETDEWEB)

    Grizzle, P.L.; Wilson, C.A.; Ferrero, E.P.; Coleman, H.J.

    1977-05-01

    Four different techniques for sample preparation were evaluated for determining vanadium and nickel in crude oils by atomic absorption (AA) spectroscopy: (1) The flame-analyzed dilution method which consists of direct-flame AA analysis after diluting the sample with a suitable organic solvent; (2) the flame-analyzed, wet-ashing method in which the sample is combusted and the residue is then dissolved before flame analysis; (3) the flameless, dilution method which involves flameless AA analysis of the sample following dilution with a suitable organic solvent; and (4) the direct, flameless method in which the crude oil or residue is directly analyzed by flameless AA. The flame-analyzed dilution method yielded erratic and inaccurate analytical results for samples of crude oils as well as for a residual sample containing standard amounts of vanadium and nickel; hence, it is unsatisfactory for oil-identification. Similarly, the direct, flameless method is unsatisfactory owing to the small concentration range available for analysis (less than approximately 15 ppM). Both the flame-analyzed, wet-ashing and flameless-dilution methods yield reliable and reproducible (better than 10%) quantitative data for nickel and vanadium in crude oils and crude oil residues. Results demonstrate that the error associated with the loss of volatile metal containing compounds upon wet-ashing is within the reproducibility of the technique. Although wet-ashing may be slightly more reproducible, the flameless-dilution method is much simpler and faster and is recommended as the better of the two procedures for routine determinations of trace metals for oil identification.

  3. Matrix effects on the determination of manganese in geological materials by atomic-absorption spectrophotometry under different flame conditions

    Science.gov (United States)

    Sanzolone, R.F.; Chao, T.T.

    1978-01-01

    Suppression caused by five of the seven matrix elements studied (Si, Al, Fe, Ca and Mg) was observed in the atomic-absorption determination of manganese in geological materials, when synthetic solutions and the recommended oxidizing air-acetylene flame were used. The magnitude of the suppression effects depends on (1) the kind and concentration of the interfering elements, (2) the type of acid medium, and (3) the concentration of manganese to be determined. All interferences noted are removed or alleviated by using a reducing nitrous oxide-acetylene flame. The atomic-absorption method using this flame can be applied to the determination of total and extractable manganese in a wide range of geological materials without interferences. Analyses of six U.S. Geological Survey rock standards for manganese gave results in agreement with the reported values. ?? 1978.

  4. Determination of Elements by Atomic Absorption Spectrometry in Medicinal Plants Employed to Alleviate Common Cold Symptoms

    Institute of Scientific and Technical Information of China (English)

    F Zehra Küçükbay; Ebru Kuyumcu

    2014-01-01

    Eleven important medicinal plants generally used by the people of Turkey for the treatment of com-mon cold have been studied for their mineral contents .Eleven minor and major elements (essential ,non-essen-tial and toxic) were identified in the Asplenium adiantum-nigrum L .,Althaea of ficinalis L .,Verbascum phlomoides L .,Euphorbiachamaesyce L .,Zizyphus jujube Miller ,Peganum harmala L .,Arum dioscori-dis Sm .,Sambucus nigra L .,Piper longum L .,Tussilago farfara L .and Elettariacardamomum Maton by employing flame atomic absorption and emission spectrometry and electro-thermal atomic absorption spectrom-etry .Microwave digestion procedure for total concentration was applied under optimized conditions for dissolu-tion of medicinal plants .Plant based biological certified reference materials (CRMs) served as standards for quantification .These elements are found to be present in varying concentrations in the studied plants .The baseline data presented in this work can be used in understanding the role of essential ,non-essential and toxic elements in nutritive ,preventive and therapeutic properties of medicinal plants .

  5. Application of microemulsions in determination of chromium naphthenate in gasoline by flame atomic absorption spectroscopy.

    Science.gov (United States)

    Du, B; Wei, Q; Wang, S; Yu, W

    1997-10-01

    A new method using microemulsified samples is presented. It is for the determination of chromium naphthenate in gasoline by flame absorption spectroscopy. The method has the advantage of simplicity, speed and the use of aqueous standards for calibration instead of organic standards. Coexistent elements do not disturb the determination. Results obtained by this method were better than those obtained by other methods for the same samples.

  6. DETERMINATION OF COPPER AND ZINC IN MINERAL WATERS BY ATOMIC ABSORPTION SPECTROPHOTOMETRY

    Directory of Open Access Journals (Sweden)

    Tatiana Mitina

    2011-12-01

    Full Text Available The content of copper and zinc in mineral waters were determined by atomic spectroscopy with preliminary extraction of metals. Validation of the technique was carried out by the method of standard additions and proved the reliability of analytical data.

  7. Determination of cadmium and lead in edible oils by electrothermal atomic absorption spectrometry after reverse dispersive liquid-liquid microextraction.

    Science.gov (United States)

    López-García, Ignacio; Vicente-Martínez, Yesica; Hernández-Córdoba, Manuel

    2014-06-01

    The dispersive liquid-liquid microextraction of edible oils with a low volume of an acidic solution in the presence of isopropyl alcohol allows cadmium and lead to be completely separated into the aqueous phase. After centrifugation, the metals are determined by electrothermal atomization atomic absorption spectrometry using a palladium salt for chemical modification in the heating cycle. Using a 10 g oil sample, the enrichment factor is 140, which permits detection limits of 0.6 and 10 ng kg(-1) for cadmium and lead, respectively. The results agree with those obtained after sample mineralization. Data for the cadmium and lead levels for 15 samples of different characteristics are given.

  8. Determination of the total iron content of used lubricating oils by atomic-absorption with use of emulsions.

    Science.gov (United States)

    Salvador, A; de la Guardia, M; Berenguer, V

    1983-12-01

    A new method is proposed for the determination of the total iron content of used lubricating oils. It is based on treatment of the samples with a mixture of hydrofluoric and nitric acids (without destruction of the organic matter) and emulsification, followed by atomic-absorption measurement. This allows the use of aqueous standards and provides a simple, rapid, inexpensive and accurate method, that is not affected by the particle size of the solids in the oil.

  9. Determination of Mercury in an Assortment of Dietary Supplements Using an Inexpensive Combustion Atomic Absorption Spectrometry Technique

    OpenAIRE

    Levine, Keith E.; Levine, Michael A.; Weber, Frank X.; Hu, Ye; Perlmutter, Jason; Grohse, Peter M.

    2005-01-01

    The concentrations of mercury in forty, commercially available dietary supplements, were determined using a new, inexpensive analysis technique. The method involves thermal decomposition, amalgamation, and detection of mercury by atomic absorption spectrometry with an analysis time of approximately six minutes per sample. The primary cost savings from this approach is that labor-intensive sample digestion is not required prior to analysis, further automating the analytical procedure. As a res...

  10. Cloud point extraction for the determination of copper in environmental samples by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Ardeshir Shokrollahi

    2008-01-01

    Full Text Available A simple cloud point extraction procedure is presented for the preconcentration of copper in various samples. After complexation by 4-hydroxy-2-mercapto-6-propylpyrimidine (PTU, copper ions are quantitatively extracted into the phase rich in Triton X-114 after centrifugation. Methanol acidified with 0.5 mol L-1 HNO3 was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS. Analytical parameters including concentrations for PTU, Triton X-114 and HNO3, bath temperature, centrifugation rate and time were optimized. The influences of the matrix ions on the recoveries of copper ions were investigated. The detection limits (3SDb/m, n=4 of 1.6 ng mL-1 along with enrichment factors of 30 for Cu were achieved. The proposed procedure was applied to the analysis of environmental samples.

  11. Determination of As, Cd, Cu, Hg and Pb in biological samples by modern electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sardans, Jordi, E-mail: j.sardans@creaf.uab.ca [Ecophysiological and Global Change Unit CSIC-CREAF, Edifici C, Universitat Autonoma de Barcelona, Bellaterra 08193, Barcelona (Spain); Montes, Fernando [Departamento de Ciencias Analiticas, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/ Senda del Rey 9. 28040 Madrid (Spain); Penuelas, Josep [Ecophysiological and Global Change Unit CSIC-CREAF, Edifici C, Universitat Autonoma de Barcelona, Bellaterra 08193, Barcelona (Spain)

    2010-02-15

    Pollution from heavy metals has increased in recent decades and has become an important concern for environmental agencies. Arsenic, cadmium, copper, mercury and lead are among the trace elements that have the greatest impact and carry the highest risk to human health. Electrothermal atomic absorption spectrometry (ETAAS) has long been used for trace element analyses and over the past few years, the main constraints of atomic absorption spectrometry (AAS) methods, namely matrix interferences that provoked high background absorption and interferences, have been reduced. The use of new, more efficient modifiers and in situ trapping methods for stabilization and pre-concentration of these analytes, progress in control of atomization temperatures, new designs of atomizers and advances in methods to correct background spectral interferences have permitted an improvement in sensitivity, an increase in detection power, reduction in sample manipulation, and increase in the reproducibility of the results. These advances have enhanced the utility of Electrothermal atomic absorption spectrometry (ETAAS) for trace element determination at mug L{sup -1} levels, especially in difficult matrices, giving rise to greater reproducibility, lower economic cost and ease of sample pre-treatment compared to other methods. Moreover, the recent introduction of high resolution continuum source Electrothermal atomic absorption spectrometry (HR-CS-ETAAS) has facilitated direct solid sampling, reducing background noise and opening the possibility of achieving even more rapid quantitation of some elements. The incorporation of flow injection analysis (FIA) systems for automation of sample pre-treatment, as well as chemical vapor generation renders (ETAAS) into a feasible option for detection of As and Hg in environmental and food control studies wherein large numbers of samples can be rapidly analyzed. A relatively inexpensive approach with low sample consumption provide additional advantages

  12. Absolute number densities of helium metastable atoms determined by atomic absorption spectroscopy in helium plasma-based discharges used as ambient desorption/ionization sources for mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Reininger, Charlotte; Woodfield, Kellie [Brigham Young University, Department of Chemistry and Biochemistry, Provo, UT 84602 (United States); Keelor, Joel D.; Kaylor, Adam; Fernández, Facundo M. [Georgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta, GA 30332 (United States); Farnsworth, Paul B., E-mail: paul_farnsworth@byu.edu [Brigham Young University, Department of Chemistry and Biochemistry, Provo, UT 84602 (United States)

    2014-10-01

    The absolute number densities of helium atoms in the 2s {sup 3}S{sub 1} metastable state were determined in four plasma-based ambient desorption/ionization sources by atomic absorption spectroscopy. The plasmas included a high-frequency dielectric barrier discharge (HF-DBD), a low temperature plasma (LTP), and two atmospheric-pressure glow discharges, one with AC excitation and the other with DC excitation. Peak densities in the luminous plumes downstream from the discharge capillaries of the HF-DBD and the LTP were 1.39 × 10{sup 12} cm{sup −3} and 0.011 × 10{sup 12} cm{sup −3}, respectively. Neither glow discharge produced a visible afterglow, and no metastable atoms were detected downstream from the capillary exits. However, densities of 0.58 × 10{sup 12} cm{sup −3} and 0.97 × 10{sup 12} cm{sup −3} were measured in the interelectrode regions of the AC and DC glow discharges, respectively. Time-resolved measurements of metastable atom densities revealed significant random variations in the timing of pulsed absorption signals with respect to the voltage waveforms applied to the discharges. - Highlights: • We determine He metastable number densities for four plasma types • The highest number densities were observed in a dielectric barrier discharge • No helium metastable atoms were observed downstream from the exits of glow discharges.

  13. A comparison of simultaneous plasma, atomic absorption, and iron colorimetric determinations of major and trace constituents in acid mine waters

    Science.gov (United States)

    Ball, J.W.; Nordstrom, D.K.

    1994-01-01

    Sixty-three water samples collected during June to October 1982 from the Leviathan/Bryant Creek drainage basin were originally analyzed by simultaneous multielement direct-current plasma (DCP) atomic-emission spectrometry, flame atomic-absorption spectrometry, graphite-furnace atomic-absorption spectrometry (GFAAS) (thallium only), ultraviolet-visible spectrometry, and hydride-generation atomic-absorption spectrometry.Determinations were made for the following metallic and semi-metallic constituents: AI, As, B, Ba, Be, Bi, Cd, Ca, Cr, Co, Cu, Fe(11), Fe(total), Li, Pb, Mg, Mn, Mo, Ni, K, Sb, Se, Si, Na, Sr, TI, V, and Zn. These samples were re-analyzed later by simultaneous multielement inductively coupled plasma (ICP) atomic-emission spectrometry and Zeeman-corrected GFAAS to determine the concentrations of many of the same constituents with improved accuracy, precision, and sensitivity. The result of this analysis has been the generation of comparative concentration values for a significant subset of the solute constituents. Many of the more recently determined values replace less-than-detection values for the trace metals; others constitute duplicate analyses for the major constituents. The multiple determinations have yielded a more complete, accurate, and precise set of analytical data. They also have resulted in an opportunity to compare the performance of the plasma-emission instruments operated in their respective simultaneous multielement modes. Flame atomic-absorption spectrometry was judged best for Na and K and hydride-generation atomic-absorption spectrometry was judged best for As because of their lower detection limit and relative freedom from interelement spectral effects. Colorimetric determination using ferrozine as the color agent was judged most accurate, precise, and sensitive for Fe. Cadmium, lead, and vanadium concentrations were too low in this set of samples to enable a determination of whether ICP or DCP is a more suitable technique. Of

  14. Determination of silver in soils, sediments, and rocks by organic-chelate extraction and atomic absorption spectrophotometry

    Science.gov (United States)

    Chao, T.T.; Ball, J.W.; Nakagawa, H.M.

    1971-01-01

    A useful method for the determination of silver in soil, sediment, and rock samples in geochemical exploration has been developed. The sample is digested with concentrated nitric acid, and the silver extracted with triisooctyl thiophosphate (TOTP) in methyl isobutyl ketone (MIBK) after dilution of the acid digest to approximately 6 M. The extraction of silver into the organic extractant is quantitative and not affected by the nitric acid concentration from 4 M to 8 M, or by different volumes of TOTP-MIBK. The extracted silver is stable and remains in the organic phase up to several days. The silver concentration is determined by atomic absorption spectrophotometry. ?? 1971.

  15. Determination of toxic metals in some herbal drugs through atomic absorption spectroscopy.

    Science.gov (United States)

    Hina, Bushra; Rizwani, Ghazala Hafeez; Naseem, Shahid

    2011-07-01

    This study presents a picture of occurrence of heavy metals (Pb, Cd, Cu, Cr, Co, Fe, Ni, Zn) in some selected valuable herbal drugs (G. glabra, O. bracteatum, V. odorata , F. vulgare, C. cyminum, C. sativum, and Z. officinalis) purchased from three different zones (southern, eastern, and western) of Karachi city using atomic absorption spectrophotometer. Heavy metal concentrations in these drugs were found in the range of: 3.26-30.46 for Pb, 1.6-4.91 for Cd, 0.65-120.21 for Cu, 83.74-433.76 for Zn, 1.61-186.75 for Cr, 0.48-76.97 for Ni, 5.54-77.97 for Co and 65.68-1652.89 µg/g for Fe. Percentage of heavy metals that were found beyond the permissible limits were: 71.4% for Pb, 28.51% for Cd, 14.2% for Cu, and 9.5 % for Cr. Significant difference was noticed for each heavy metal among herbal drugs as well as their zones of collection using two way ANOVA followed by least significant (LSD) test at p<0.05.Purpose of this research is to detect each type of heavy metal contaminant of herbal drugs by environmental pollution, as well as to highlight the health risks associated with the use of such herbal drugs that contain high levels of toxic heavy metals.

  16. Determination of selenium and tellurium in the gas phase using specific columns and atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Muangnoicharoen, S.; Chiou, K.Y.; Manuel, O.K.

    1986-11-01

    Total selenium and tellurium in the gas phase were analyzed after adsorption on gold-coated beads and charcoal. The thermally eluting gas was trapped on columns filled with quartz beads that were cooled in an ice bath. The beads were boiled in dilute HCl, and the resulting solution was analyzed for Se and Te by graphite furnace atomic absorption spectrometry. Their results demonstrate that gold-coated beads efficiently trap gaseous Se and Te at a low gas flow rate, but at higher flow rates charcoal traps are more expedient. With charcoal traps, it was found that local air samples contain Se in the range of 0.92-3.05 ng m/sup -3/ and Te in the range of 0.10-0.34 ng m/sup -3/. Detection limits down to about 0.1 ng m/sup -3/ allow the ready detection of Se and Te in rural air with a precision of about +/- 6% at the nanogram level of Te and about +/- 4% at the nanogram level of Se.

  17. Colorimetric and atomic absorption spectrometric determination of mucolytic drug ambroxol through ion-pair formation with iron and thiocyanate.

    Science.gov (United States)

    Levent, Abdulkadir; Sentürk, Zühre

    2010-09-01

    Colorimetric and atomic absorption spectrometric methods have been developed for the determination of mucolytic drug Ambroxol. These procedures depend upon the reaction of iron(III) metal ion with the drug in the presence of thiocyanate ion to form stable ion-pair complex which extractable chloroform. The red-coloured complex was determined either colorimetrically at 510 nm or by indirect atomic absorption spectrometry (AAS) via the determination of the iron content in the formed complex. The optimum experimental conditions for pH, concentrations of Fe(3+) and SCN(-), shaking time, phase ratio, and the number of extractions were determined. Under the proposed conditions, linearity was obeyed in the concentration ranges 4.1x10(-6) - 5.7x10(-5) M (1.7-23.6 µg mL(-1)) using both methods, with detection limits of 4.6x10(-7) M (0.19 µg mL(-1)) for colorimetry and 1.1x10(-6) M (0.46 µg mL(-1)) for AAS. The proposed methods were applied for the determination of Ambroxol in tablet dosage forms. The results obtained were statistically analyzed and compared with those obtained by applying the high-performance liquid chromatographic method with diode-array detection.

  18. Determination of cadmium by electrothermal atomic absorption spectrometry after microwave-assisted digestion of animal tissues and sewage sludges.

    Science.gov (United States)

    Chakraborty, R; Das, A K; Cervera, M L; De La Guardia, M

    1996-04-01

    The determination of cadmium in different sample types has been carried out by electrothermal atomization atomic absorption spectrometry with D(2)-background correction using a unpyrocoated graphite tube, after pressurized microwave-assisted digestion. Five chemical modifiers [(NH(4))(2)HPO(4), Pd(NO)(3))(2), Ni(NO(3))(2), thiourea and Triton X-100] have been assayed and nickel nitrate has been found to be most effective for an accurate determination of cadmium in mussel tissue, pig kidney and sewage sludge. The characteristic mass of the method is of the order of 1 pg and the limit of detection is lower than 0.1 ng/ml.

  19. Application of methane as a gaseous modifier for the determination of silicon using electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Heinrich, Hans-Joachim, E-mail: hans-joachim.heinrich@bam.de; Kipphardt, Heinrich

    2012-04-15

    For determination of silicon in aqueous solutions by electrothermal atomic absorption spectrometry methane/argon mixtures as a gaseous modifier were applied during the pyrolysis step to improve the analytical performance. The beneficial effects observed on thermal stabilization, signal enhancement and shape of absorbance signals were attributed to the thermal decomposition products of methane, which were hydrogen and carbon black (soot). Using a 5% CH{sub 4} mixture with argon, the optimized pyrolysis and atomization temperatures were 1350 Degree-Sign C and 2450 Degree-Sign C, respectively. A flushing step following the pyrolysis was mandatory to avoid background absorption and accelerated deposition of pyrolytic graphite. Characteristic masses of 50 and 30 pg were obtained for standard transversely heated graphite atomizer (THGA) tubes and end-capped THGA tubes, respectively, which were lower than with other previously applied modifiers. A limit of detection of 0.2 {mu}g L{sup -1} (3 s, n = 10) has been obtained. In addition, this gaseous modifier did not contribute to contamination which often was significant when a liquid modifier solution was co-injected. The proposed method has been applied to the determination of silicon in ultrapure water, nitric and hydrochloric acids. - Highlights: Black-Right-Pointing-Pointer CH{sub 4}/Ar gas mixtures act as new modifier in the determination of Si using ET AAS. Black-Right-Pointing-Pointer CH{sub 4} improved thermal stabilization, atomization efficiency and signal shape of Si. Black-Right-Pointing-Pointer Optimum performance by addition of 5% CH{sub 4} during pyrolysis at 1350 Degree-Sign C. Black-Right-Pointing-Pointer Gaseous modifier does not contribute to blank values. Black-Right-Pointing-Pointer Optimized method suitable for determination of Si in ultrapure reagents.

  20. Methylmercury determination using a hyphenated high performance liquid chromatography ultraviolet cold vapor multipath atomic absorption spectrometry system

    Science.gov (United States)

    Campos, Reinaldo C.; Gonçalves, Rodrigo A.; Brandão, Geisamanda P.; Azevedo, Marlo S.; Oliveira, Fabiana; Wasserman, Julio

    2009-06-01

    The present work investigates the use of a multipath cell atomic absorption mercury detector for mercury speciation analysis in a hyphenated high performance liquid chromatography assembly. The multipath absorption cell multiplies the optical path while energy losses are compensated by a very intense primary source. Zeeman-effect background correction compensates for non-specific absorption. For the separation step, the mobile phase consisted in a 0.010% m/v mercaptoethanol solution in 5% methanol (pH = 5), a C 18 column was used as stationary phase, and post column treatment was performed by UV irradiation (60 °C, 13 W). The eluate was then merged with 3 mol L - 1 HCl, reduction was performed by a NaBH 4 solution, and the Hg vapor formed was separated at the gas-liquid separator and carried through a desiccant membrane to the detector. The detector was easily attached to the system, since an external gas flow to the gas-liquid separator was provided. A multivariate approach was used to optimize the procedure and peak area was used for measurement. Instrumental limits of detection of 0.05 µg L - 1 were obtained for ionic (Hg 2+) and HgCH 3+, for an injection volume of 200 µL. The multipath atomic absorption spectrometer proved to be a competitive mercury detector in hyphenated systems in relation to the most commonly used atomic fluorescence and inductively coupled plasma mass spectrometric detectors. Preliminary application studies were performed for the determination of methyl mercury in sediments.

  1. Methylmercury determination using a hyphenated high performance liquid chromatography ultraviolet cold vapor multipath atomic absorption spectrometry system

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Reinaldo C. [Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, Rua Marques de S Vicente 225, 22453-900 Rio de Janeiro (Brazil)], E-mail: rccampos@puc-rio.br; Goncalves, Rodrigo A.; Brandao, Geisamanda P.; Azevedo, Marlo S. [Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, Rua Marques de S Vicente 225, 22453-900 Rio de Janeiro (Brazil); Oliveira, Fabiana; Wasserman, Julio [Institut of Geosciences, Fluminense Federal University, Av. Gal. Milton Tavares de Souza, s/n, 24.210-340, Niteroi, Rio de Janeiro (Brazil)

    2009-06-15

    The present work investigates the use of a multipath cell atomic absorption mercury detector for mercury speciation analysis in a hyphenated high performance liquid chromatography assembly. The multipath absorption cell multiplies the optical path while energy losses are compensated by a very intense primary source. Zeeman-effect background correction compensates for non-specific absorption. For the separation step, the mobile phase consisted in a 0.010% m/v mercaptoethanol solution in 5% methanol (pH = 5), a C{sub 18} column was used as stationary phase, and post column treatment was performed by UV irradiation (60 deg. C, 13 W). The eluate was then merged with 3 mol L{sup -1} HCl, reduction was performed by a NaBH{sub 4} solution, and the Hg vapor formed was separated at the gas-liquid separator and carried through a desiccant membrane to the detector. The detector was easily attached to the system, since an external gas flow to the gas-liquid separator was provided. A multivariate approach was used to optimize the procedure and peak area was used for measurement. Instrumental limits of detection of 0.05 {mu}g L{sup -1} were obtained for ionic (Hg{sup 2+}) and HgCH{sub 3}{sup +}, for an injection volume of 200 {mu}L. The multipath atomic absorption spectrometer proved to be a competitive mercury detector in hyphenated systems in relation to the most commonly used atomic fluorescence and inductively coupled plasma mass spectrometric detectors. Preliminary application studies were performed for the determination of methyl mercury in sedi0011men.

  2. Simple Atomic Absorption Spectroscopic and Spectrophotometric Methods for Determination of Pioglitazone Hydrochloride and Carvedilol in Pharmaceutical Dosage Forms

    Directory of Open Access Journals (Sweden)

    Afaf A. Abdelmonem

    2014-01-01

    Full Text Available This study represents simple atomic absorption spectroscopic and spectrophotometric methods for determination of pioglitazone hydrochloride (PGZ-HCl and carvedilol (CRV based on formation of ion-pair associates between drugs and inorganic complex, bismuth(III tetraiodide (Method A and between drugs and organic acidic dyes, fast green and orange G (Method B. Method A is based on formation of ion-pair associate between drugs and bismuth(III tetraiodide in acidic medium to form orange-red ion-pair associates, which can be quantitatively determined by two different procedures. The formed ion-pair associate is extracted by methylene chloride, dissolved in acetone, dried, and then decomposed by hydrochloric acid, and bismuth content is determined by direct atomic absorption spectrometric technique (Procedure 1 or extracted by methylene chloride, dissolved in acetone, and quantified spectrophotometrically at 490 nm (Procedure 2. Method B is based on formation of ion-pair associate between drugs and either fast green dye or orange G dye in acidic medium to form ion-pair associates. The formed ion-pair associate is extracted by methylene chloride and quantified spectrophotometrically at 630 nm (for fast green dye method or 498 nm (for orange G dye method. Optimal experimental conditions have been studied. Both methods are applied for determination of the drugs in tablets without interference.

  3. A preconcentration system for determination of copper and nickel in water and food samples employing flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tuzen, Mustafa [Department of Chemistry, Gaziosmanpasa University, 60250 Tokat (Turkey); Soylak, Mustafa [Department of Chemistry, Erciyes University, 38039 Kayseri (Turkey)], E-mail: soylak@erciyes.edu.tr; Citak, Demirhan [Department of Chemistry, Gaziosmanpasa University, 60250 Tokat (Turkey); Ferreira, Hadla S.; Korn, Maria G.A. [Universidade Federal da Bahia, Instituto de Quimica, 40170-290 Salvador (Brazil); Bezerra, Marcos A. [Universidade Estadual do Sudoeste da Bahia, 45200-190 Jequie (Brazil)

    2009-03-15

    A separation/preconcentration procedure using solid phase extraction has been proposed for the flame atomic absorption spectrometric determination of copper and nickel at trace level in food samples. The solid phase is Dowex Optipore SD-2 resin contained on a minicolumn, where analyte ions are sorbed as 5-methyl-4-(2-thiazolylazo) resorcinol chelates. After elution using 1 mol L{sup -1} nitric acid solution, the analytes are determinate employing flame atomic absorption spectrometry. The optimization step was performed using a full two-level factorial design and the variables studied were: pH, reagent concentration (RC) and amount of resin on the column (AR). Under the experimental conditions established in the optimization step, the procedure allows the determination of copper and nickel with limit of detection of 1.03 and 1.90 {mu}g L{sup -1}, respectively and precision of 7 and 8%, for concentrations of copper and nickel of 200 {mu}g L{sup -1}. The effect of matrix ions was also evaluated. The accuracy was confirmed by analyzing of the followings certified reference materials: NIST SRM 1515 Apple leaves and GBW 07603 Aquatic and Terrestrial Biological Products. The developed method was successfully applied for the determination of copper and nickel in real samples including human hair, chicken meat, black tea and canned fish.

  4. An abbreviated fire-assay atomic-absorption method for the determination of gold and silver in ores and concentrates.

    Science.gov (United States)

    Moloughney, P E

    1977-02-01

    A simplified scheme, combining aspects of the classical fire-assay with an atomic-absorption finish, is presented for the determination of gold and silver in ores and concentrates. The lead assay button is scorified to approximately 2 g and then parted in nitric acid. The filtrate is analysed by AAS for silver; the residue is dissolved in aqua regia and subsequently analysed for gold by AAS. The precision and accuracy of the method have been established by application to four diverse certified reference materials. The proposed method eliminates the need for such time-consuming steps as inquartation, multiple scorifications, and cupellation.

  5. [Determination of Pb and Al in blood and hair of child using transverse heated graphite furnace atomic absorption spectroscopy].

    Science.gov (United States)

    Niu, Feng-lan; Xie, Wen-bing; Li, Chen-xu; Dong, Wei-yan

    2005-04-01

    Pb and Al in blood and hair of child were determined by transverse heated graphite furnace atomic absorption spectrometry with NH4H2PO4 and Mg(NO3)2 as a modifier, which enhanced the temperature of ashing, eliminated the matrix interference and memorial effect. The method is rapid, simple and accurate. The characteristic mass of the method was 2.3 x 10(-11) g and 2.2 x 10(-11) g for Pb and Al respectively. The relative standard deviation of Pb and Al was 3.0% and 11.4%, respectively, and the recovery was 96%-102%.

  6. Direct determination of lead in human urine and serum samples by electrothermal atomic absorption spectrometry and permanent modifiers

    OpenAIRE

    Andrada,Daniel; Pinto,Frederico G.; Magalhães, Cristina Gonçalves; Nunes,Berta R.; Franco,Milton B.; Silva,José Bento Borba da

    2006-01-01

    The object of the present study was the development of alternative methods for the direct determination of lead in undigested samples of human urine and serum by electrothermal atomic absorption spectrometry (ET AAS). Thus, some substances have been investigated to act as chemical modifiers. Volumes of 20 µL of diluted samples, 1 + 1, v/v for urine and 1 + 4, v/v for serum, with HNO3 1% v/v and 0.02% v/v of cetil trimethyl ammonium chloride (CTAC) were prepared directly in the autosampler cup...

  7. Direct determination of cadmium in Orujo spirit samples by electrothermal atomic absorption spectrometry: Comparative study of different chemical modifiers

    Energy Technology Data Exchange (ETDEWEB)

    Vilar Farinas, M. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain); Barciela Garcia, J. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain); Garcia Martin, S. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain); Pena Crecente, R. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain); Herrero Latorre, C. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain)]. E-mail: cherrero@lugo.usc.es

    2007-05-22

    In this work, several analytical methods are proposed for cadmium determination in Orujo spirit samples using electrothermal atomic absorption spectrometry (ETAAS). Permanent chemical modifiers thermally coated on the platforms inserted in pyrolytic graphite tubes (such as W, Ir, Ru, W-Ir and W-Ru) were comparatively studied in relation to common chemical modifier mixtures [Pd-Mg(NO{sub 3}){sub 2} and (NH{sub 4})H{sub 2}PO{sub 4}-Mg(NO{sub 3}){sub 2}] for cadmium stabilization. Different ETAAS Cd determination methods based on the indicated modifiers have been developed. In each case, pyrolysis and atomization temperatures, atomization shapes, characteristic masses and detection limits as well as other analytical characteristics have been determined. All the assayed modifiers (permanent and conventional) were capable of achieving the appropriate stabilization of the analyte, with the exception of Ru and W-Ru. Moreover, for all developed methods, recoveries (99-102%) and precision (R.S.D. lower than 10%) were acceptable. Taking into account the analytical performance (best detection limit LOD = 0.01 {mu}g L{sup -1}), the ETAAS method based on the use of W as a permanent modifier was selected for further direct Cd determinations in Orujo samples from Galicia (NW Spain). The chosen method was applied in the determination of the Cd content in 38 representative Galician samples. The cadmium concentrations ranged

  8. Absolute number densities of helium metastable atoms determined by atomic absorption spectroscopy in helium plasma-based discharges used as ambient desorption/ionization sources for mass spectrometry

    Science.gov (United States)

    Reininger, Charlotte; Woodfield, Kellie; Keelor, Joel D.; Kaylor, Adam; Fernández, Facundo M.; Farnsworth, Paul B.

    2014-10-01

    The absolute number densities of helium atoms in the 2s 3S1 metastable state were determined in four plasma-based ambient desorption/ionization sources by atomic absorption spectroscopy. The plasmas included a high-frequency dielectric barrier discharge (HF-DBD), a low temperature plasma (LTP), and two atmospheric-pressure glow discharges, one with AC excitation and the other with DC excitation. Peak densities in the luminous plumes downstream from the discharge capillaries of the HF-DBD and the LTP were 1.39 × 1012 cm- 3 and 0.011 × 1012 cm- 3, respectively. Neither glow discharge produced a visible afterglow, and no metastable atoms were detected downstream from the capillary exits. However, densities of 0.58 × 1012 cm- 3 and 0.97 × 1012 cm- 3 were measured in the interelectrode regions of the AC and DC glow discharges, respectively. Time-resolved measurements of metastable atom densities revealed significant random variations in the timing of pulsed absorption signals with respect to the voltage waveforms applied to the discharges.

  9. Chromium speciation by solid phase extraction on Dowex M 4195 chelating resin and determination by atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Saygi, Kadriye Ozlem; Tuzen, Mustafa [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Soylak, Mustafa [Erciyes University, Faculty of Science and Arts, Chemistry Department, 38039 Kayseri (Turkey)], E-mail: msoylak@gmail.com; Elci, Latif [Pamukkale University, Faculty of Science and Arts, Chemistry Department, 20020 Denizli (Turkey)

    2008-05-30

    A solid phase extraction procedure has been established for chromium speciation in natural water samples prior to determination by atomic absorption spectrometry. The procedure is based on the solid phase extraction of the Cr(VI)- Dowex M 4195 chelating resin. After oxidation of Cr(III) to Cr(VI) by using H{sub 2}O{sub 2}, the presented method was applied to the determination of the total chromium. The level of Cr(III) is calculated by difference of total chromium and Cr(VI) levels. The procedure was optimized for some analytical parameters including pH, eluent type, flow rates of sample and eluent, matrix effects, etc. The presented method was applied for the speciation of chromium in natural water samples with satisfactory results (recoveries >95%, RSDs <10%). In the determinations of chromium species, flame atomic absorption spectrometer was used. The results were checked by using NIST SRM 2711 Montana soil and GBW 07603 Bush branched and leaves.

  10. Microwave-assisted extraction and ultrasonic slurry sampling procedures for cobalt determination in geological samples by electrothermal atomic absorption spectroscopy.

    Science.gov (United States)

    Felipe-Sotelo, M; Carlosena, A; Fernández, E; López-Mahía, P; Muniategui, S; Prada, D

    2004-06-17

    Slurry sampling is compared to microwave-assisted acid digestion for cobalt determination in soil/sediment samples by electrothermal atomic absorption spectrometry (ETAAS). Furnace temperature programs and appropriate amounts of three chemical modifiers were optimised in order to get the highest signals and good separations between the atomic and background signals. Using nitric acid (0.5% (v/v)) as liquid medium, no chemical modifier was needed. The detection limit, based on integrated absorbance, was 0.04mugg(-1) for digests and slurries. Within-batch precision and analytical recoveries were satisfactory for both procedures. Accuracy was tested by analysing a reference soil and a sediment from IRMM. The methods were further compared employing a set of roadside soils and estuarine sediments. As no significant differences (95% confidence) were found, practical analytical properties were suggested in order to select one of them.

  11. Comparison of Adsorbed Mercury Screening Method With Cold-Vapor Atomic Absorption Spectrophotometry for Determination of Mercury in Soil

    Science.gov (United States)

    Easterling, Donald F.; Hovanitz, Edward S.; Street, Kenneth W.

    2000-01-01

    A field screening method for the determination of elemental mercury in environmental soil samples involves the thermal desorption of the mercury from the sample onto gold and then the thermal desorption from the gold to a gold-film mercury vapor analyzer. This field screening method contains a large number of conditions that could be optimized for the various types of soils encountered. In this study, the conditions were optimized for the determination of mercury in silty clay materials, and the results were comparable to the cold-vapor atomic absorption spectrophotometric method of determination. This paper discusses the benefits and disadvantages of employing the field screening method and provides the sequence of conditions that must be optimized to employ this method of determination on other soil types.

  12. [Determination of trace silver in water samples by solid phase extraction portable tungsten-coil electrothermal atomic absorption spectrometry].

    Science.gov (United States)

    Fan, Guang-yu; Jiang, Xiao-ming; Zheng, Cheng-bin; Hou, Xian-deng; Xu, Kai-lai

    2011-07-01

    A simple method has been developed for the determination of silver in environmental water samples using solid phase extraction with tungsten-coil electrothermal atomic absorption spectrometry. Silica gel was used as an adsorbent and packed into a syringe barrel for solid phase extraction of silver prior to its determination by using a portable tungsten-coil electrothermal atomic absorption spectrometer. Optimum conditions for adsorption and desorption of silver ion, as well as interferences from co-existing ions, were investigated. A sample pH value of 6.0, a sample loading flow rate of 4.0 mL x min(-1), and the mixture of 4% (m/v) thiourea and 2% (phi) nitrate acid with the eluent flow rate of 0.5 mL x min(-1) for desorption were selected for further studies. Under optimal conditions, a linear range of 0.20-4.00 ng x mL(-1), a limit of detection (3sigma) of 0.03 ng x mL(-1) and a preconcentration factor of 94 were achieved. The proposed method was validated by testing three environmental water samples with satisfactory results.

  13. Study of the roles of chemical modifiers in determining boron using graphite furnace atomic absorption spectrometry and optimization of the temperature profile during atomization.

    Science.gov (United States)

    Yamamoto, Yuhei; Shirasaki, Toshihiro; Yonetani, Akira; Imai, Shoji

    2015-01-01

    The measurement conditions for determining boron using graphite furnace-atomic absorption spectrometry (GF-AAS) were investigated. Differences in the boron absorbance profiles were found using three different commercially available GF-AAS instruments when the graphite atomizers in them were not tuned. The boron absorbances found with and without adjusting the graphite atomizers suggested that achieving an adequate absorbance for the determination of boron requires a sharp temperature profile that overshoots the target temperature during the atomization process. Chemical modifiers that could improve the boron absorbance without the need for using coating agents were tested. Calcium carbonate improved the boron absorbance but did not suppress variability in the peak height. Improvement of boron absorbance was comparatively less using iron nitrate or copper nitrate than using calcium carbonate, but variability in the peak height was clearly suppressed using iron nitrate or copper nitrate. The limit of detection was 0.0026 mg L(-1) when iron nitrate was used. It appears that iron nitrate is a useful new chemical modifier for the quick and simple determination of boron using GF-AAS.

  14. Determination of silver, bismuth, cadmium, copper, lead, and zinc in geologic materials by atomic absorption spectrometry with tricaprylylmethylammonium chloride

    Science.gov (United States)

    Viets, J.G.

    1978-01-01

    Interferences commonly encountered in the determination of silver, bismuth, cadmium, copper, lead, and zinc at crustal abundance levels are effectively eliminated using a rapid, sensitive, organic extraction technique. A potassium chlorate-hydrochloric acid digestion solubilizes the metals not tightly bound in the silicate lattice of rocks, soils, and stream sediments. The six metals are selectively extracted into a 10% Aliquat 336-MIBK organic phase in the presence of ascorbic acid and potassium iodide. Metals in the organic extract are determined by flame atomic absorption spectrometry to the 0.02-ppm level for silver, cadmium, copper, and zinc and to the 0.2-ppm level for bismuth and lead with a maximum relative standard deviation of 18.8% for known reference samples. An additional hydrofluoric acid digestion may be used to determine metals substituted in the silicate lattice.

  15. Determination of Ultratrace Amounts of Copper(Ⅱ) in Water Samples by Electrothermal Atomic Absorption Spectrometry After Cloud Point Extraction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry (ETAAS) after cloud point extraction (CPE). 1-( 2-Pyridylazo)-2-naphthol was used as the chelating reagent and Triton X-114 as the micellar-forming surfactant. CPE was conducted in a pH 8.0 medium at 40 ℃ for 10 min. After the separation of the phases by centrifugation, the surfactant-rich phase was diluted with 1 mL of a methanol solution of 0. 1 mol/L HNO3. Then 20 μL of the diluted surfactant-rich phase was injected into the graphite furnace for atomization in the absence of any matrix modifier. Various experimental conditions that affect the extraction and atomization processes were optimized. A detection limit of 5 ng/L was obtained after preconcentration. The linear dynamic range of the copper mass concentration was found to be 0-2.0ng/mL, and the relative standard deviation was found to be less than 3.1% for a sample containing 1.0 ng/mL Cu(Ⅱ). This developed method was successfully applied to the determination of ultratrace amounts of Cu in drinking water, tap water, and seawater samples.

  16. Determination of mercury in an assortment of dietary supplements using an inexpensive combustion atomic absorption spectrometry technique.

    Science.gov (United States)

    Levine, Keith E; Levine, Michael A; Weber, Frank X; Hu, Ye; Perlmutter, Jason; Grohse, Peter M

    2005-01-01

    The concentrations of mercury in forty, commercially available dietary supplements, were determined using a new, inexpensive analysis technique. The method involves thermal decomposition, amalgamation, and detection of mercury by atomic absorption spectrometry with an analysis time of approximately six minutes per sample. The primary cost savings from this approach is that labor-intensive sample digestion is not required prior to analysis, further automating the analytical procedure. As a result, manufacturers and regulatory agencies concerned with monitoring lot-to-lot product quality may find this approach an attractive alternative to the more classical acid-decomposition, cold vapor atomic absorption methodology. Dietary supplement samples analyzed included astragalus, calcium, chromium picolinate, echinacea, ephedra, fish oil, ginger, ginkgo biloba, ginseng, goldenseal, guggul, senna, St John's wort, and yohimbe products. Quality control samples analyzed with the dietary supplements indicated a high level of method accuracy and precision. Ten replicate preparations of a standard reference material (NIST 1573a, tomato leaves) were analyzed, and the average mercury recovery was 109% (2.0% RSD). The method quantitation limit was 0.3 ng, which corresponded to 1.5 ng/g sample. The highest found mercury concentration (123 ng/g) was measured in a concentrated salmon oil sample. When taken as directed by an adult, this product would result in an approximate mercury ingestion of 7 mug per week.

  17. Development of a cloud point extraction and preconcentration method for Cd and Ni prior to flame atomic absorption spectrometric determination

    Energy Technology Data Exchange (ETDEWEB)

    Manzoori, Jamshid L. [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)]. E-mail: manzoori@tabrizu.ac.ir; Karim-Nezhad, Ghasem [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2004-09-13

    In this work a new cloud point extraction (CPE) methodology was developed for the separation and preconcentration of cadmium and nickel. The analyte in the initial aqueous solution was complexed with dithizone and Triton X-114 was added as surfactant. After phase separation, based on the cloud point of the mixture, and dilution of the surfactant-rich phase with tetrahydrofuran (THF), the enriched analytes were determined by flame atomic absorption spectrometry. After optimization of the complexation and extraction conditions and preconcentration of only 10 ml of sample in the presence of 0.05% Triton X-114, the enhancement factors of 52 and 39 and the detection limits of 0.31 {mu}g l{sup -1} and 1.2 {mu}g l{sup -1} were obtained for cadmium and nickel respectively. The proposed method was applied satisfactorily to the determination of cadmium and nickel in water samples.

  18. Determination of mercury in estuarine sediments by flow injection-cold vapour atomic absorption spectrometry after microwave extraction

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Garcia, M.L.; Carlosena, A.; Lopez-Mahia, P.; Muniategui, S.; Prada, D. [University of La Coruna (Spain). Dept. Analytical Chemistry

    1999-01-01

    A flow injection-cold vapour atomic absorption spectrometric (CVAAS) method was developed for the determination of mercury at trace level in estuarine sediments using sodium tetra-hydro-borate (III) as reductant. The mercury was solubilized with nitric acid in closed vessels nd microwave oven heating. Instrumental and operational conditions (volume and concentration of reagents, reaction time, etc.) were optimized. The effect of several ions on the analytical signal was also studied; no interferences were recorded excepting for copper and nickel which caused a serious depressing effect. The detection limit obtained was 0.01 {mu}g g{sup -1}. The validation of the method was performed analyzing a certified reference sediment, BCR CRM 277 Estuarine Sediment. Good recovery (c.a. 98 %) and precision (< 3 %, RSD) were achieved. The proposed method was successfully applied to the determination of mercury in sediment samples from Ares-Betanzos Estuary (Galicia, NW Spain). (authors) 19 refs.

  19. Membrane filtration of nickel(II) on cellulose acetate filters for its preconcentration, separation, and flame atomic absorption spectrometric determination

    Energy Technology Data Exchange (ETDEWEB)

    Soylak, Mustafa [Chemistry Dept., Faculty of Science Arts, University of Erciyes, Kayseri (Turkey); Unsal, Yunus Emre; Aydin, Ayse [Fen Bilimleri Enstitusu, University of Erciyes, Kayseri (Turkey); Kizil, Nebiye [Saglik Bilimleri Enstitusu, University of Erciyes, Kayseri (Turkey)

    2010-01-15

    An enrichment method for trace amounts of Ni(II), as 8-hydroxyquinoline chelates, has been established on a cellulose acetate membrane filter. Ni(II)-8-hydroxyquinoline chelates adsorbed on a membrane filter were eluted using 5 mL of 1 M HNO{sub 3}. The eluent nickel concentration was determined by a flame atomic absorption spectrometer. The influence of some analytical parameters, including pH, amount of reagent, sample volume, etc., on recovery was investigated. The interference of co-existent ions was studied. The nickel detection limit was 4.87 {mu}g/L. The method was applied to real samples for the determination of nickel(II) ions. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  20. Coprecipitation of trace amounts of silicon with aluminum hydroxide and the determination by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Ardeshir Shokrollahi

    2014-01-01

    Full Text Available A simple preconcentration method of silicon based on coprecipitation with aluminum hydroxide prior to its flame atomic absorption (FAAS determination was established. The recovery values of analyte ion was higher than 95%. The parameters including types of hydroxide ion source for precipitation, acid type for dissolution step, amount of aluminum ion as collector, pH, temperature, standing and centrifuge time, and sample volume were optimized for the quantitative recovery of the analyte. The influences of matrix ions were also examined. The relative standard deviation was found to be 3.2%. The limit of detection was calculated as (0.1 mg L-1. The preconcentration factor is 100 for (200 mL solution. The proposed method was successfully applied for the determination of silicon in some water and alloy samples.

  1. Solid phase extraction of gold(III) on Amberlite XAD-2000 prior to its flame atomic absorption spectrometric determination.

    Science.gov (United States)

    Elci, Latif; Sahan, Derya; Basaran, Aydan; Soylak, Mustafa

    2007-09-01

    A solid phase extraction method for the determination of gold(III) at trace levels by flame atomic absorption spectrometer (FAAS) was developed. The method was based on retention of gold as chloro complexes through the Amberlite XAD-2000. The effect of some analytical parameters including hydrochloric acid concentration, sample volume, sample and eluent flow rates, eluent volume, eluent concentration and interfering ions on the recovery of gold(III) was investigated. The retention of gold(III) from 1.5 mol l(-1) HCl solution and the recovery of gold with 0.07 mol l(-1) NH3 solution were quantitative (>or=95%). The relative standard deviation (RSD) was calculated as 3.2% (n = 10). The detection limit for gold was 2 microg l(-1). The accuracy was checked with the determination of gold spiked an artificial seawater and a pure copper samples.

  2. Determination of total tin in geological materials by electrothermal atomic-absorption spectrophotometry using a tungsten-impregnated graphite furnace

    Science.gov (United States)

    Zhou, L.; Chao, T.T.; Meier, A.L.

    1984-01-01

    An electrothermal atomic-absorption spectrophotometric method is described for the determination of total tin in geological materials, with use of a tungsten-impregnated graphite furnace. The sample is decomposed by fusion with lithium metaborate and the melt is dissolved in 10% hydrochloric acid. Tin is then extracted into trioctylphosphine oxide-methyl isobutyl ketone prior to atomization. Impregnation of the furnace with a sodium tungstate solution increases the sensitivity of the determination and improves the precision of the results. The limits of determination are 0.5-20 ppm of tin in the sample. Higher tin values can be determined by dilution of the extract. Replicate analyses of eighteen geological reference samples with diverse matrices gave relative standard deviations ranging from 2.0 to 10.8% with an average of 4.6%. Average tin values for reference samples were in general agreement with, but more precise than, those reported by others. Apparent recoveries of tin added to various samples ranged from 95 to 111% with an average of 102%. ?? 1984.

  3. Nickel and strontium nitrates as modifiers for the determination of selenium in wine by Zeeman electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Cvetković, J; Stafilov, T; Mihajlović, D

    2001-08-01

    A mixed matrix modifier of nickel and strontium nitrates was used as a chemical modifier for the determination of selenium in wines by Zeeman electrothermal atomic absorption spectrometry. Wine samples were heated on a boiling water bath with small amounts of nitric acid and hydrogen peroxide. For complete elimination of interference, especially from sulfates and phosphates, selenium is complexed with ammonium pyrolidinedithiocarbamate (APDTC), extracted into methyl isobutyl ketone (MIBK), and measured by ETAAS. The graphite furnace temperature program was optimized for both aqueous and organic solutions. Pyrolysis temperatures of 1300 degrees C and 800 degrees C were chosen for aqueous and organic solutions, respectively; 2700 degrees C and 2100 degrees C were used as optimum atomization temperatures for aqueous and organic solutions, respectively. The optimum modifier mass established is markedly lower than those presented in the literature. The platform atomization ensures pretreatment stabilization up to 1100 degrees C and 1600 degrees C, respectively, for organic and aqueous selenium solutions. The procedure was verified by the method of standard addition. The investigated wine samples originated from the different regions of the Republic of Macedonia. The selenium concentration varied from not detectable to 0.93 microg L(-1).

  4. Determination of lead in wine and rum samples by flow injection-hydride generation-atomic absorption spectrometry.

    Science.gov (United States)

    Elçi, Latif; Arslan, Zikri; Tyson, Julian F

    2009-03-15

    A method for direct determination of lead in wine and rum samples was developed, using a flow injection hydride generation system coupled to an atomic absorption spectrometer with flame-quartz atomizer (FI-HG-AAS). Lead hyride (PbH(4)) was generated using potassium ferricyanide (K(3)Fe(CN)(6)), as oxidant and sodium tetrahydroborate (NaBH(4)) as reductant. Samples were acidified to 0.40% (v/v) HCl for wine and to 0.30% (v/v) HCl for rum, which were then mixed on-line with 3% (m/v) K(3)Fe(CN)(6) solution in 0.03% (v/v) HCl prior to reaction with 0.2% (m/v) alkaline NaBH(4) solution. Lead contents of a rum and two different red wine samples were determined by FI-HG-AAS agreed with those obtained by ICP-MS. The analytical figures of merit of method developed were determined. The calibration curve was linear up to 8.0 microg L(-1) Pb with a regression coefficient of 0.998. The relative error was lower than 4.58%. The relative standard deviation (n=7) was better than 12%. A detection limit of 0.16 microg L(-1) was achieved for a sample volume of 170 microL.

  5. Determination of silicon and aluminum in silicon carbide nanocrystals by high-resolution continuum source graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Dravecz, Gabriella; Bencs, László; Beke, Dávid; Gali, Adam

    2016-01-15

    The determination of Al contaminant and the main component Si in silicon carbide (SiC) nanocrystals with the size-distribution of 1-8nm dispersed in an aqueous solution was developed using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS-GFAAS). The vaporization/atomization processes were investigated in a transversally heated graphite atomizer by evaporating solution samples of Al and Si preserved in various media (HCl, HNO3). For Si, the best results were obtained by applying a mixture of 5µg Pd plus 5µg Mg, whereas for Al, 10µg Mg (each as nitrate solution) was dispensed with the samples, but the results obtained without modifier were found to be better. This way a maximum pyrolysis temperature of 1200°C for Si and 1300°C for Al could be used, and the optimum (compromise) atomization temperature was 2400°C for both analytes. The Si and Al contents of different sized SiC nanocrystals, dispersed in aqueous solutions, were determined against aqueous (external) calibration standards. The correlation coefficients (R values) of the calibrations were found to be 0.9963 for Si and 0.9991 for Al. The upper limit of the linear calibration range was 2mg/l Si and 0.25mg/l Al. The limit of detection was 3µg/l for Si and 0.5µg/l for Al. The characteristic mass (m0) was calculated to be 389pg Si and 6.4pg Al. The Si and Al content in the solution samples were found to be in the range of 1.0-1.7mg/l and 0.1-0.25mg/l, respectively.

  6. Cloud point extraction thermospray flame quartz furnace atomic absorption spectrometry for determination of ultratrace cadmium in water and urine

    Science.gov (United States)

    Wu, Peng; Zhang, Yunchang; Lv, Yi; Hou, Xiandeng

    2006-12-01

    A simple, low cost and highly sensitive method based on cloud point extraction (CPE) for separation/preconcentration and thermospray flame quartz furnace atomic absorption spectrometry was proposed for the determination of ultratrace cadmium in water and urine samples. The analytical procedure involved the formation of analyte-entrapped surfactant micelles by mixing the analyte solution with an ammonium pyrrolidinedithiocarbamate (APDC) solution and a Triton X-114 solution. When the temperature of the system was higher than the cloud point of Triton X-114, the complex of cadmium-PDC entered the surfactant-rich phase and thus separation of the analyte from the matrix was achieved. Under optimal chemical and instrumental conditions, the limit of detection was 0.04 μg/L for cadmium with a sample volume of 10 mL. The analytical results of cadmium in water and urine samples agreed well with those by ICP-MS.

  7. Cloud point extraction-thermospray flame quartz furnace atomic absorption spectrometry for determination of ultratrace cadmium in water and urine

    Energy Technology Data Exchange (ETDEWEB)

    Wu Peng [Analytical and Testing Center, Sichuan University, Chengdu, Sichuan 610064 (China); Zhang Yunchang [College of Chemistry, Sichuan University, Chengdu, Sichuan 610064 (China); Lv Yi [College of Chemistry, Sichuan University, Chengdu, Sichuan 610064 (China); Hou Xiandeng [Analytical and Testing Center, Sichuan University, Chengdu, Sichuan 610064 (China) and College of Chemistry, Sichuan University, Chengdu, Sichuan 610064 (China)]. E-mail: houxd@scu.edu.cn

    2006-12-15

    A simple, low cost and highly sensitive method based on cloud point extraction (CPE) for separation/preconcentration and thermospray flame quartz furnace atomic absorption spectrometry was proposed for the determination of ultratrace cadmium in water and urine samples. The analytical procedure involved the formation of analyte-entrapped surfactant micelles by mixing the analyte solution with an ammonium pyrrolidinedithiocarbamate (APDC) solution and a Triton X-114 solution. When the temperature of the system was higher than the cloud point of Triton X-114, the complex of cadmium-PDC entered the surfactant-rich phase and thus separation of the analyte from the matrix was achieved. Under optimal chemical and instrumental conditions, the limit of detection was 0.04 {mu}g/L for cadmium with a sample volume of 10 mL. The analytical results of cadmium in water and urine samples agreed well with those by ICP-MS.

  8. Cloud point extraction and flame atomic absorption spectrometric determination of cadmium and nickel in drinking and wastewater samples.

    Science.gov (United States)

    Naeemullah; Kazi, Tasneem G; Shah, Faheem; Afridi, Hassan I; Baig, Jameel Ahmed; Soomro, Abdul Sattar

    2013-01-01

    A simple method for the preconcentration of cadmium (Cd) and nickel (Ni) in drinking and wastewater samples was developed. Cloud point extraction has been used for the preconcentration of both metals, after formation of complexes with 8-hydroxyquinoline (8-HQ) and extraction with the surfactant octylphenoxypolyethoxyethanol (Triton X-114). Dilution of the surfactant-rich phase with acidified ethanol was performed after phase separation, and the Cd and Ni contents were measured by flame atomic absorption spectrometry. The experimental variables, such as pH, amounts of reagents (8-HQ and Triton X-114), temperature, incubation time, and sample volume, were optimized. After optimization of the complexation and extraction conditions, enhancement factors of 80 and 61, with LOD values of 0.22 and 0.52 microg/L, were obtained for Cd and Ni, respectively. The proposed method was applied satisfactorily for the determination of both elements in drinking and wastewater samples.

  9. Speciation determination of chromium(III) and (VI) using preconcentration cloud point extraction with flame atomic absorption spectrometry (FAAS)

    Energy Technology Data Exchange (ETDEWEB)

    Kiran, K. [Department of Environmental Sciences, S.V. University, Tirupati, 517502 A.P. (India); Kumar, K. Suresh; Prasad, B.; Suvardhan, K. [Department of Chemistry, S. V. University, Tirupati, 517502 A.P. (India); Lekkala, Ramesh Babu [Department of Environmental Sciences, S.V. University, Tirupati, 517502 A.P. (India); Janardhanam, K. [Department of Environmental Sciences, S.V. University, Tirupati, 517502 A.P. (India)], E-mail: Kandukurijanardhanam@gmail.com

    2008-02-11

    bis-[2-Hydroxy-1-naphthaldehyde] thiourea was synthesized and preconcentration cloud point extraction (CPE) for speciation determination of chromium(III) and (VI) in various environmental samples with flame atomic absorption spectrometry (FAAS) has been developed. Chromium(III) complexes with bis-[2-hydroxynaphthaldehyde] thiourea is subsequently entrapped in the surfactant micelles. After complexation of chromium(III) with reagent, the analyte was quantitatively extracted to the surfactant-rich phase in the non-ionic surfactant Triton X-100 after centrifugation. The effect of pH, concentration of chelating agent, surfactant, equilibration temperature and time on CPE was studied. The relative standard deviation was 2.13% and the limits of detection were around 0.18 {mu}g L{sup -1}.

  10. Lead determination at ng/mL level by flame atomic absorption spectrometry using a tantalum coated slotted quartz tube atom trap.

    Science.gov (United States)

    Demirtaş, İlknur; Bakırdere, Sezgin; Ataman, O Yavuz

    2015-06-01

    Flame atomic absorption spectrometry (FAAS) still keeps its importance despite the relatively low sensitivity; because it is a simple and economical technique for determination of metals. In recent years, atom traps have been developed to increase the sensitivity of FAAS. Although the detection limit of FAAS is only at the level of µg/mL, with the use of atom traps it can reach to ng/mL. Slotted quartz tube (SQT) is one of the atom traps used to improve sensitivity. In atom trapping mode of SQT, analyte is trapped on-line in SQT for few minutes using ordinary sample aspiration, followed by the introduction of a small volume of organic solvent to effect the revolatilization and atomization of analyte species resulting in a transient signal. This system is economical, commercially available and easy to use. In this study, a sensitive analytical method was developed for the determination of lead with the help of SQT atom trapping flame atomization (SQT-AT-FAAS). 574 Fold sensitivity enhancement was obtained at a sample suction rate of 3.9 mL/min for 5.0 min trapping period with respect to FAAS. Organic solvent was selected as 40 µL of methyl isobutyl ketone (MIBK). To obtain a further sensitivity enhancement inner surface of SQT was coated with several transition metals. The best sensitivity enhancement, 1650 fold enhancement, was obtained by the Ta-coated SQT-AT-FAAS. In addition, chemical nature of Pb species trapped on quartz and Ta surface, and the chemical nature of Ta on quartz surface were investigated by X-ray photoelectron spectroscopy (XPS) and Raman Spectroscopy. Raman spectrometric results indicate that tantalum is coated on SQT surface in the form of Ta2O5. XPS studies revealed that the oxidation state of Pb in species trapped on both bare and Ta coated SQT surfaces is +2. For the accuracy check, the analyses of standard reference material were performed by use of SCP SCIENCE EnviroMAT Low (EU-L-2) and results for Pb were to be in good agreement with

  11. Determination of vanadium in urine by electrothermal atomic absorption spectrometry using hot injection and preconcentration into the graphite tube

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Kelly G.; Nobrega, Joaquim A. [Sao Carlos Univ., SP (Brazil). Dept. de Quimica; Nogueira, Ana Rita A. [Embrapa Pecuaria Sudeste, Sao Carlos, SP (Brazil)]. E-mail: anarita@cppse.embrapa.br; Gomes Neto, Jose A. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica

    2004-10-01

    In this work it was developed a procedure for the determination of vanadium in urine samples by electrothermal atomic absorption spectrometry using successive injections for preconcentration into a preheated graphite tube. Three 60 {mu}L volumes were sequentially injected into the atomizer preheated to a temperature of 110 deg C. Drying and pyrolysis steps were carried out after each injection. A chemical modifier, barium difluoride (100 mg L{sup -1}), and a surfactant, Triton X-100 (0.3% v v{sup -1}), were added to the urine sample. When injecting into a hot graphite tube, the sample flow-rate was 0.5 {mu} s{sup -1}. The limits of detection and quantification were 0.54 and 1.82 without preconcentration, and 0.11 and 0.37 {mu}g L{sup -1} with preconcentration, respectively. The accuracy of the procedure was evaluated by an addition-recovery experiment employing urine samples. Recoveries varied from 96.0 to 103% for additions ranging from 0.8 to 3.5 {mu}g L{sup -1} V. The developed procedure allows the determination of vanadium in urine without any sample pretreatment and with minimal dilution of the sample. (author)

  12. Cloud point extraction for the determination of cadmium and lead in biological samples by graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Maranhão, Tatiane De A.; Borges, Daniel L. G.; da Veiga, Márcia A. M. S.; Curtius, Adilson J.

    2005-06-01

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of Cd and Pb from digested biological samples. After complexation with O,O-diethyldithiophosphate (DDTP) in hydrochloric acid medium, the analytes are quantitatively extracted to the phase rich in the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 0.1 mol L-1 HNO3 was added to the surfactant-rich phase prior to its analysis by electrothermal atomic absorption spectrometry (ET AAS). The adopted concentrations for DDTP, Triton X-114 and hydrochloric acid were all optimized. Pyrolysis and atomization temperatures were optimized using the extracts and pyrolysis temperatures of 700 °C for both elements and atomization temperatures of 1400 and 1600 °C for cadmium and lead, respectively, were used without adding any modifier, which shows that considerable analyte stabilization is provided by the medium itself. A more detailed investigation was carried out to determine which components of the extract were responsible for the high thermal stability achieved and it revealed that the amount of DDTP added and the phosphorus content of the digested samples contributed significantly to this phenomenon. Detection limits (3σB) of 6 and 40 ng g-1, along with enrichment factors of 129 and 18 for Cd and Pb, respectively, were achieved. The proposed procedure was applied to the analysis of five certified biological reference materials after microwave-assisted acid digestion in a mixture of H2O2 and HNO3. Comparison with certified values was performed for accuracy evaluation, resulting in good agreement according to the t-test for a 95% confidence level. The high efficiency of cloud point extraction to carry out the determination of the studied analytes in complex matrices was, therefore, demonstrated.

  13. Cloud point extraction for the determination of cadmium and lead in biological samples by graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Maranhao, Tatiane de A. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Borges, Daniel L.G. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)]. E-mail: daniel@qmc.ufsc.br; Veiga, Marcia A.M.S. da [Instituto de Quimica, Universidade de Sao Paulo, 05513-970, CP 26077, Sao Paulo, SP (Brazil); Curtius, Adilson J. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)

    2005-06-30

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of Cd and Pb from digested biological samples. After complexation with O,O-diethyldithiophosphate (DDTP) in hydrochloric acid medium, the analytes are quantitatively extracted to the phase rich in the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 0.1 mol L{sup -1} HNO{sub 3} was added to the surfactant-rich phase prior to its analysis by electrothermal atomic absorption spectrometry (ET AAS). The adopted concentrations for DDTP, Triton X-114 and hydrochloric acid were all optimized. Pyrolysis and atomization temperatures were optimized using the extracts and pyrolysis temperatures of 700 deg. C for both elements and atomization temperatures of 1400 and 1600 deg. C for cadmium and lead, respectively, were used without adding any modifier, which shows that considerable analyte stabilization is provided by the medium itself. A more detailed investigation was carried out to determine which components of the extract were responsible for the high thermal stability achieved and it revealed that the amount of DDTP added and the phosphorus content of the digested samples contributed significantly to this phenomenon. Detection limits (3{sigma} {sub B}) of 6 and 40 ng g{sup -1}, along with enrichment factors of 129 and 18 for Cd and Pb, respectively, were achieved. The proposed procedure was applied to the analysis of five certified biological reference materials after microwave-assisted acid digestion in a mixture of H{sub 2}O{sub 2} and HNO{sub 3}. Comparison with certified values was performed for accuracy evaluation, resulting in good agreement according to the t-test for a 95% confidence level. The high efficiency of cloud point extraction to carry out the determination of the studied analytes in complex matrices was, therefore, demonstrated.

  14. Determination of total arsenic content in water by atomic absorption spectroscopy (AAS) using vapour generation assembly (VGA).

    Science.gov (United States)

    Behari, Jai Raj; Prakash, Rajiv

    2006-03-01

    Analysis of arsenic in water is important in view of contamination of ground water with arsenic in some parts of the world including West Bengal in India and neighboring country Bangladesh. WHO has fixed the threshold for arsenic in drinking water to 10ppb (microg/l) level, hence the methodology for determination of arsenic is required to be sensitive at ppb level. Atomic absorption spectrophotometry with vapour generation assembly (AAS-VGA) is well known technique for the trace analysis of arsenic. However, total arsenic analysis [As(III)+As(V)] is very crucial and it requires reduction of As(V) to As(III) for correct analysis. As(III) is reduced to AsH3 vapours and finally to free As atoms, which are responsible for absorption signal in AAS. To accomplish this the vapour generation assembly attached to AAS has acid channel filled with 10 M HCl and the reduction channel with sodium borohydride. Further sample can be reduced either before aspiration for analysis, using potassium iodide (KI) or the sample can be introduced in the instrument directly and KI can be added in the reduction channel along with the sodium borohydride. The present work shows that samples prepared in 3 M HCl can be reduced with KI for 30 min before introduction in the instrument. Alternatively samples can be prepared in 6 M HCl and directly aspirated in AAS using KI in VGA reduction channel. The latter methodology is more useful when the sample size is large and time cycle is difficult to maintain. It is observed that the acid concentration of the sample in both the situations plays an important role. Further reduction in acid concentration and analysis time is achieved for the arsenic analysis by using modified method. Analysis in both the methods is sensitive at ppb level.

  15. [Investigation of determining strontium in M. nitida Benth. var. hirsutissima. Z. Wei. by flame atomic absorption spectra].

    Science.gov (United States)

    Zhang, Ling; Rao, Zhi-Jun; Guan, Yuan-Yuan; Zhang, Hai-Ming

    2010-12-01

    The present paper is aimed to establish the method of determining the strontium in M. nitida Benth. var. hirsutissima. Z. Wei. by means of air-acetylene flame atomic absorption spectra, and also provide reference for the determination of the strontium in other traditional Chinese medicine. M. Nitida Benthvarhirsutissima Z. Wei. was taken as the object. The authors used nitric-perchloric acid as digestion solution to digest samples by microwave which was controlled by pressure, and used EDTA-2Na as the releasing agent to add in the samples for determining the strontium in M. nitida Benth. var. hirsutissima. Z. Wei. by FAAS. The results showed that the samples were entirely digested by microwave. The working curve was Y = 0.036 5x -0.001 1, r = 0.999 4, the range was 0-1.6 microg x mL(-1), the average recovery rate was 101.5% with RSD 2.04%, and the method detection limit was 0.008 2 microg x mL(-1) (n = 21). It is concluded that this method is simple and accurate. It has high sensitivity and can be effectively used for determining the strontium in this traditional Chinese medicine.

  16. Determination of Trace Amounts of Nickel (Ⅱ) by Graphite Furnace Atomic Absorption Spectrometry Coupled with Cloud Point Extraction

    Institute of Scientific and Technical Information of China (English)

    SHAH Syed Mazhar; WANG Hao-nan; SU Xing-guang

    2011-01-01

    A new method based on the cloud point extraction(CPE) for separation and preconcentration of nickel(Ⅱ)and its subsequent determination by graphite furnace atomic absorption spectrometry(GFAAS) was proposed,8-hydroxyquinoline and Triton X-100 were usedl as the ligand and surfactant respectively. Nickel(Ⅱ) can form a hydrophobic complex with 8-hydroxyquinoline, the complex can be extracted into the small volume surfactant rich phase at the cloud point temperature(CPT) for GFAAS determination. The factors affecting the cloud point extraction,such as pH, ligand concentration, surfactant concentration, and the incubation time were optimized. Under the optimal conditions, a detection limit of 12 ng/L and a relative standard deviation(RSD) of 2.9% were obtained for Ni(Ⅱ) determination. The enrichment factor was found to be 25. The proposed method was successfully applied to the determination of nickel(Ⅱ) in certified reference material and different types of water samples and the recovery was in a range of 95% 103%.

  17. Determination of trace lead in rice of sewage irrigation by graphite furnace atomic-absorption spectrometry

    Institute of Scientific and Technical Information of China (English)

    JIXueping; RENJujie

    1994-01-01

    The early literatures reported that a lot of matrix interference were encounted in the determination of lend content in various samples. Chlorides produced serious interference on analysis of lead content. All acids except phosphoric acid reduced sensitivity of determination of Pb. Hinderberger et al.

  18. Determination of cadmium in rice and water by tungsten coil electrothermal vaporization-atomic fluorescence spectrometry and tungsten coil electrothermal atomic absorption spectrometry after cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Wen Xiaodong [College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China); Wu Peng [Analytical and Testing Center, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China); Chen Li [College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China); Hou Xiandeng, E-mail: houxd@scu.edu.cn [College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China); Analytical and Testing Center, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China)

    2009-09-14

    In this work, the microsampling nature of tungsten coil electrothermal vaporization Ar/H{sub 2} flame atomic fluorescence spectrometry (W-coil ETV-AFS) as well as tungsten coil electrothermal atomic absorption spectrometry (W-coil ET-AAS) was used with cloud point extraction (CPE) for the ultrasensitive determination of cadmium in rice and water samples. When the temperature of the extraction system is higher than the cloud point temperature of the selected surfactant Triton X-114, the complex of cadmium with dithizone can be quantitatively extracted into the surfactant-rich phase and subsequently separated from the bulk aqueous phase by centrifugation. The main factors affecting the CPE, such as concentration of Triton X-114 and dithizone, pH, equilibration temperature and incubation time, were optimized for the best extract efficiency. Under the optimal conditions, the limits of detection for cadmium by W-coil ETV-AFS and W-coil ET-AAS were 0.01 and 0.03 {mu}g L{sup -1}, with sensitivity enhancement factors of 152 and 93, respectively. The proposed methods were applied to the determination of cadmium in certified reference rice and water samples with analytical results in good agreement with certified values.

  19. Determination of trace nickel in water samples by cloud point extraction preconcentration coupled with graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sun Zhimei [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China); Department of Chemistry and Biology, Huainan Normal University, Huainan 232001 (China); Liang Pei [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)]. E-mail: liangpei@mail.ccnu.edu.cn; Ding Qiong [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China); Cao Jing [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)

    2006-09-21

    A new method based on the cloud point extraction (CPE) preconcentration and graphite furnace atomic absorption spectrometry (GFAAS) detection was proposed for the determination of trace nickel in water samples. When the micelle solution temperature is higher than the cloud point of surfactant p-octylpolyethyleneglycolphenyether (Triton X-100), the complex of Ni{sup 2+} with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) could enter surfactant-rich phase and be concentrated, then determined by GFAAS. The main factors affecting the cloud point extraction were investigated in detail. An enrichment factor of 27 was obtained for the preconcentration of Ni{sup 2+} with 10 mL solution. Under the optimal conditions, the detection limit of Ni{sup 2+} is 0.12 ng mL{sup -1} with R.S.D. of 4.3% (n = 10, c = 100 ng mL{sup -1}). The proposed method was applied to determination of trace nickel in water samples with satisfactory results.

  20. Flame Atomic Absorption Determination of Gold Ion in Aqueous Samples after Preconcentration Using 9-Acridinylamine Functionalized γ-Alumina Nanoparticles

    Directory of Open Access Journals (Sweden)

    Mohammad Karimi

    2013-01-01

    Full Text Available A simple and sensitive solid phase extraction utilizing 9-acridinylamine functionalized alumina nanoparticles was developed, and their potential use for preconcentration and subsequent determination of gold by flame atomic absorption spectrometry (FAAS was investigated. A number of parameters, namely, type, concentration, and volume of eluent, pH of the sample solution, flow rate of extraction, and volume of the sample, were evaluated. The effect of a variety of ions on preconcentration and recovery was also investigated. Gold ions were found to be recovered quantitatively at pH 3.0, with 0.1 mol L−1 thiourea in 2 mol L−1 H2SO4 as eluent. The limit of detection (LOD, defined as five times the standard deviation of the blank, was determined to be lower than 13.0 ppb. Under optimum conditions, the accuracy and precision (RSD% of the method were >98.0 and <1.5%, respectively. To gauge its ability in terms of application to real samples, the proposed method was successfully applied for determination of gold concentration in waste water samples and one soil standard material, and satisfactory results were obtained.

  1. [Determination of trace elements in Lophatherum gracile brongn from different habitat by microwave digestion-atomic absorption spectroscopy].

    Science.gov (United States)

    Yuan, Ke; Xue, Yue-Qin; Gui, Ren-Yi; Sun, Su-Qin; Yin, Ming-Wen

    2010-03-01

    A method of microwave digestion technique was proposed to determine the content of Zn, Fe, Cu, Mn, K, Ca, Mg, Ni, Cd, Pb, Cr, Co, Al, Se and As in Lophatherum gracile brongn of different habitat by atomic absorption spectroscopy. The RSD of the method was between 1.23% and 3.32%, and the recovery rates obtained by standard addition method were between 95.8% and 104.20%. The results of the study indicate that the proposed method has the advantages of simplicity, speediness and sensitivity. It is suitable for the determination of the contents of metal elements in Lophatherum gracile brongn. The experimental results also indicated that different areas' Lophantherum gracile brongn had different trace elements content. The content of trace elements K, Mg, Ca, Fe and Mn beneficial to the human body was rich. The content of the heavy metal trace element Pb in Lophantherum gracile brongn of Hunan province was slightly high. The content of the heavy metal trace element Cu in Lophantherum gracile brongn of Guangdong province and Anhui province is also slightly higher. Beside, the contents of harmful trace heavy metal elements Cd, Cu, Cr, Pb and As in Lophatherum gracile brongn of different habitat are all lower than the limits of Chinese Pharmacopoeia and Green Trade Standard for Importing and Exporting Medicinal Plant and Preparation and National Food Sanitation Standard. These determination results provided the scientific data for further discussing the relationship between the content of trace elements in Lophantherum gracile brongn and the medicine efficacy.

  2. Sensitive determination of cadmium in water samples by room temperature ionic liquid-based preconcentration and electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Martinis, Estefania M. [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT - CONICET - Mendoza), Av. Ruiz Leal S/N Parque General San Martin, C.C. 131, M 5502 IRA Mendoza (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Olsina, Roberto A. [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis (Argentina); Altamirano, Jorgelina C. [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT - CONICET - Mendoza), Av. Ruiz Leal S/N Parque General San Martin, C.C. 131, M 5502 IRA Mendoza (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza (Argentina); Wuilloud, Rodolfo G. [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT - CONICET - Mendoza), Av. Ruiz Leal S/N Parque General San Martin, C.C. 131, M 5502 IRA Mendoza (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza (Argentina)], E-mail: rwuilloud@mendoza-conicet.gov.ar

    2008-10-17

    A sensitive preconcentration methodology for Cd determination at trace levels in water samples was developed in this work. 1-Butyl-3-methylimidazolium hexafluorophosphate ([C{sub 4}MIM][PF{sub 6}]) room temperature ionic liquid (RTIL) was successfully used for Cd preconcentration, as cadmium-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol complex [Cd-5-Br-PADAP]. Subsequently, Cd was back-extracted from the RTIL phase with 500 {mu}L of 0.5 mol L{sup -1} nitric acid and determined by electrothermal atomic absorption spectrometry (ETAAS). A preconcentration factor of 40 was achieved with 20 mL of sample. The limit of detection (LOD) obtained under optimum conditions was 3 ng L{sup -1} and the relative standard deviation (R.S.D.) for 10 replicates at 1 {mu}g L{sup -1} Cd{sup 2+} concentration level was 3.5%, calculated at peak heights. The calibration graph was linear from concentration levels near the detection limits up to at least 5 {mu}g L{sup -1}. A correlation coefficient of 0.9997 was achieved. Validation of the methodology was performed by standard addition method and analysis of certified reference material (CRM). The method was successfully applied to the determination of Cd in river and tap water samples.

  3. FLAME ATOMIC ABSORPTION DETERMINATION OF COPPER IN CEREALS FOOD SAMPLES WITH THE PRECONCENTRATION OF POTASSIUM TETRATITANATE WHISKER

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A simple and reliable method has been developed for separation and preconcentration of trace amounts of copper ions in cereals food for subsequent measurement by flame atomic absorption spectrometry (FAAS). The Cu2+ ions are adsorbed selectively and quantitatively during the passage. The retained copper ions were desorbed from the potassium tetratitanate whisker with 10.0mL of 2mol/L sulphuric acid solutions as eluent and were determined by FAAS. The linear range was 0.05μg/mL~0.20μg/mL in the original solution with a correlation coefficient of 0.9998. The detection limit of the proposed method is 2.1ng/mL in the original solution (3σ, n=9). Determination of copper in standard ions showed that the proposed method has good accuracy (recovery was more than 95%). The method was successfully applied for recovery and determination of copper in cereals food samples.

  4. FLAME ATOMIC ABSORPTION DETERMINATION OF COPPER IN CEREALS FOOD SAMPLES WITH THE PRECONCENTRATION OF POTASSIUM TETRATITANATE WHISKER

    Institute of Scientific and Technical Information of China (English)

    XU Wanzhen; ZHANG Xinghua; YAN Yongsheng; LIU Aiqin; JING Junjie

    2007-01-01

    A simple and reliable method has been developed for separation and preconcentration of trace amounts of copper ions in cereals food for subsequent measurement by flame atomic absorption spectrometry (FAAS). The Cu2+ ions are adsorbed selectively and quantitatively during the passage. The retained copper ions were desorbed from the potassium tetratitanate whisker with 10.0mL of 2mol/L sulphuric acid solutions as eluent and were determined by FAAS. The linear range was 0.05μg/mL~0.20μg/mL in the original solution with a correlation coefficient of 0.9998. The detection limit of the proposed method is 2.1ng/mL in the original solution (3σ, n=9). Determination of copper in standard ions showed that the proposed method has good accuracy (recovery was more than 95%). The method was successfully applied for recovery and determination of copper in cereals food samples.

  5. A method optimization study for atomic absorption spectrophotometric determination of total zinc in insulin using direct aspiration technique

    Directory of Open Access Journals (Sweden)

    Sadia Ata

    2015-03-01

    Full Text Available A sensitive, reliable and relative fast method has been developed for the determination of total zinc in insulin by atomic absorption spectrophotometer. This designed study was used to optimize the procedures for the existing methods. Spectrograms of both standard and sample solutions of zinc were recorded by measuring the absorbance at 213.9 nm for determination of total zinc. System suitability parameters were evaluated and were found to be within the limits. Linearity was evaluated through graphical representation of concentration versus absorbance. Repeatability (intra-day and intermediate precision (inter-day were assessed by analyzing working standard solutions. Accuracy and robustness were experimented from the standard procedures. The percentage recovery of zinc was found to be 99.8%, relative standard deviation RSD 1.13%, linearity of determination LOD 0.0032 μg/mL, and limit of quantization LOQ 0.0120 μg/mL. This developed and proposed method was then validated in terms of accuracy, precision, linearity and robustness which can be successfully used for the quantization of zinc in insulin.

  6. Determination of Pb(Ⅱ) and Cu(Ⅱ) by Electrothermal Atomic Absorption Spectrometry after Preconcentration by a Schiff Base Adsorbed on Surfactant Coated Alumina

    Institute of Scientific and Technical Information of China (English)

    SABER TEHRANI Mohammad; RASTEGAR Faramarz; PARCHEHBAF Ayob; KHATAMIAN Masoomeh

    2006-01-01

    1,2-Bis(salicylidenamino)ethane loaded onto sodium dodecyl sulfate-coated alumina was used as a new chelating sorbent for the preconcentration of traces of Pb(Ⅱ) and Cu(Ⅱ) prior to atomic absorption spectrometric determination. The influence of pH, flow rates of sample and eluent solutions, and foreign ions on the recovery of Pb(Ⅱ)by electrothermal atomic absorption spectrometry (ETAAS). The data of limit of detection (3σ) for Pb(Ⅱ) and Cu(Ⅱ)posed method was successfully applied to determination of lead and copper in different water samples.

  7. Determination of Cd, Pb and As in sediments of the Sava River by electrothermal atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    SIMONA MURKO

    2010-01-01

    Full Text Available The applicability of nitric acid, palladium nitrate and a mixture of palladium and magnesium nitrate as matrix modifiers were estimated for the accurate and reproducible determination of cadmium (Cd, lead (Pb and arsenic (As in sediments of the Sava River by electrothermal atomic absorption spectrometry, ETAAS. Decomposition of the samples was done in a closed vessel microwave-assisted digestion system using nitric, hydrochloric and hydrofluoric acids, followed by the addition of boric acid to convert the fluorides into soluble complexes. The parameters for the determination of Cd, Pb and As in sediments were optimised for each individual element and for each matrix modifier. In addition, two sediment reference materials were also analysed. In determination of Cd and Pb, nitric acid was found to be the most appropriate matrix modifier. The accurate and reliable determination of Cd and Pb in sediments was possible also in the presence of boric acid. The use of a mixture of palladium and magnesium nitrate efficiently compensated for matrix effects and enabled the accurate and reliable determination of As in the sediments. Quantification of Cd and As was performed by calibration using acid matched standard solutions, while the standard addition method was applied for the quantification of Pb. The repeatability of the analytical procedure for the determination of Cd, Pb and As in sediments was ±5 % for Cd, ±4 % for Pb and ±2 % for As. The LOD values of the analytical procedure were found to be 0.05 mg/kg for Cd and 0.25 mg/kg for Pb and As, while the LOQ values were 0.16 mg/kg for Cd and 0.83 mg/kg for Pb and As. Finally, Cd, Pb and As were successfully determined in sediments of the Sava River in Slovenia.

  8. Determination of serum aluminum by electrothermal atomic absorption spectrometry: A comparison between Zeeman and continuum background correction systems

    Science.gov (United States)

    Kruger, Pamela C.; Parsons, Patrick J.

    2007-03-01

    Excessive exposure to aluminum (Al) can produce serious health consequences in people with impaired renal function, especially those undergoing hemodialysis. Al can accumulate in the brain and in bone, causing dialysis-related encephalopathy and renal osteodystrophy. Thus, dialysis patients are routinely monitored for Al overload, through measurement of their serum Al. Electrothermal atomic absorption spectrometry (ETAAS) is widely used for serum Al determination. Here, we assess the analytical performances of three ETAAS instruments, equipped with different background correction systems and heating arrangements, for the determination of serum Al. Specifically, we compare (1) a Perkin Elmer (PE) Model 3110 AAS, equipped with a longitudinally (end) heated graphite atomizer (HGA) and continuum-source (deuterium) background correction, with (2) a PE Model 4100ZL AAS equipped with a transversely heated graphite atomizer (THGA) and longitudinal Zeeman background correction, and (3) a PE Model Z5100 AAS equipped with a HGA and transverse Zeeman background correction. We were able to transfer the method for serum Al previously established for the Z5100 and 4100ZL instruments to the 3110, with only minor modifications. As with the Zeeman instruments, matrix-matched calibration was not required for the 3110 and, thus, aqueous calibration standards were used. However, the 309.3-nm line was chosen for analysis on the 3110 due to failure of the continuum background correction system at the 396.2-nm line. A small, seemingly insignificant overcorrection error was observed in the background channel on the 3110 instrument at the 309.3-nm line. On the 4100ZL, signal oscillation was observed in the atomization profile. The sensitivity, or characteristic mass ( m0), for Al at the 309.3-nm line on the 3110 AAS was found to be 12.1 ± 0.6 pg, compared to 16.1 ± 0.7 pg for the Z5100, and 23.3 ± 1.3 pg for the 4100ZL at the 396.2-nm line. However, the instrumental detection limits (3

  9. Determination of serum aluminum by electrothermal atomic absorption spectrometry: A comparison between Zeeman and continuum background correction systems

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, Pamela C. [Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, P.O. Box 509, Albany, NY 12201-0509 (United States); Parsons, Patrick J. [Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, P.O. Box 509, Albany, NY 12201-0509 (United States); Lead Poisoning/Trace Elements Laboratory, Wadsworth Center, New York State Department of Health, P.O. Box 509, Albany, NY 12201-0509 (United States)], E-mail: patrick.parsons@wadsworth.org

    2007-03-15

    Excessive exposure to aluminum (Al) can produce serious health consequences in people with impaired renal function, especially those undergoing hemodialysis. Al can accumulate in the brain and in bone, causing dialysis-related encephalopathy and renal osteodystrophy. Thus, dialysis patients are routinely monitored for Al overload, through measurement of their serum Al. Electrothermal atomic absorption spectrometry (ETAAS) is widely used for serum Al determination. Here, we assess the analytical performances of three ETAAS instruments, equipped with different background correction systems and heating arrangements, for the determination of serum Al. Specifically, we compare (1) a Perkin Elmer (PE) Model 3110 AAS, equipped with a longitudinally (end) heated graphite atomizer (HGA) and continuum-source (deuterium) background correction, with (2) a PE Model 4100ZL AAS equipped with a transversely heated graphite atomizer (THGA) and longitudinal Zeeman background correction, and (3) a PE Model Z5100 AAS equipped with a HGA and transverse Zeeman background correction. We were able to transfer the method for serum Al previously established for the Z5100 and 4100ZL instruments to the 3110, with only minor modifications. As with the Zeeman instruments, matrix-matched calibration was not required for the 3110 and, thus, aqueous calibration standards were used. However, the 309.3-nm line was chosen for analysis on the 3110 due to failure of the continuum background correction system at the 396.2-nm line. A small, seemingly insignificant overcorrection error was observed in the background channel on the 3110 instrument at the 309.3-nm line. On the 4100ZL, signal oscillation was observed in the atomization profile. The sensitivity, or characteristic mass (m{sub 0}), for Al at the 309.3-nm line on the 3110 AAS was found to be 12.1 {+-} 0.6 pg, compared to 16.1 {+-} 0.7 pg for the Z5100, and 23.3 {+-} 1.3 pg for the 4100ZL at the 396.2-nm line. However, the instrumental detection

  10. Determination of platinum traces contamination by graphite furnace atomic absorption spectrometry after preconcentration by cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Chappuy, M. [Analytical Development Laboratory, Pharmaceutical Establishment of Paris Hospitals, 7 rue du Fer a Moulin, 75005 Paris (France); Caudron, E., E-mail: eric.caudron@eps.aphp.fr [Analytical Development Laboratory, Pharmaceutical Establishment of Paris Hospitals, 7 rue du Fer a Moulin, 75005 Paris (France); Groupe de Chimie Analytique de Paris-Sud, EA 4041, IFR 141, School of Pharmacy, Univ Paris-Sud, 92296 Chatenay-Malabry (France); Bellanger, A. [Department of Pharmacy, Pitie-Salpetriere Hospital (Paris Public Hospital Authority), 47 boulevard de l' hopital, 75013 Paris (France); Pradeau, D. [Analytical Development Laboratory, Pharmaceutical Establishment of Paris Hospitals, 7 rue du Fer a Moulin, 75005 Paris (France)

    2010-04-15

    A simple and sensitive method is described for the determination of platinum surface contamination originating from cisplatin, carboplatin and oxaliplatin. Following extraction from swabs and preconcentration with the cloud point extraction (CPE) method, detection was by graphite furnace atomic absorption spectrometry (GFAAS). After desorption of platinum compounds from the swab, CPE involved on preconcentration of platinum in aqueous solution with diethyldithiocarbamate (DDTC) as chelating agent and Triton X-114 as extraction medium. DDTC is not only a chelating agent, but may also be a good candidate for the inactivation of platinum compounds. DDTC is recommended by the Word Health Organization (WHO) for the destruction of platinum-based anticancer drugs. The main factors affecting CPE efficiency, pH of the sample solution, concentrations of DDTC and Triton X-114, equilibration temperature and incubation time, were evaluated in order to enhance sensitivity of the method. The desorption of platinum compounds from the swab was investigated in parallel. Since platinum is bound to DDTC, it must exchange with copper in order to enhance platinum atomizing by GFAAS. A preconcentration factor of 29 was obtained for 10 mL of a platinum solution at 10 {mu}g mL{sup -1}. In optimal conditions, the limit of detection was 0.2 ng mL{sup -1}, corresponding to 2.0 ng of platinum metal on the swab. Absorbance was linear between 0.7 and 15 ng mL{sup -1}. The proposed method was applied for the determination of surface contamination by platinum compounds with correct results.

  11. Cloud point extraction for the preconcentration of silver and palladium in real samples and determination by atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tavallali, Hossein; Yazdandoust, Saeed; Yazdandoust, Mozhdeh [Department of Chemistry, Payame Noor University (PNU), Shiraz (Iran)

    2010-03-15

    A cloud point extraction procedure is presented for the preconcentration and simultaneous determination of Ag{sup +} and Pd{sup 2+} in various samples. After complexation with 2-((2-((1H-benzo[d]imidazole-2-yl)methoxy)phenoxy)methyl)-1H-benzo[d]imidazol (BIMPI), which was used as a new chelating agent, analyte ions were quantitatively extracted to a phase rich in Triton X-114 following centrifugation, and determination was carried out by flame atomic absorption spectrometry (FAAS). Under the optimum experimental conditions (i. e., pH = 7.0, 15.0.10{sup -5} mol/L BIMPI and 0.036% (w/v) Triton X-114), calibration graphs were linear in the range of 28.0-430.0 {mu}g/L and 57.0-720.0 {mu}g/L with detection limits of 10.0 and 25.0 {mu}g/L for Ag{sup +} and Pd{sup 2+}, respectively. The enrichment factors were 35.0 and 28.0 for Ag{sup +} and Pd{sup 2+}, respectively. The method has been successfully applied to evaluate these metals in some real samples, including waste water, soil and hydrogenation catalyst samples. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  12. Preconcentration procedure using cloud point extraction in the presence of electrolyte for cadmium determination by flame atomic absorption spectrometry

    Science.gov (United States)

    Coelho, Luciana Melo; Arruda, Marco Aurélio Zezzi

    2005-06-01

    This paper describes a micelle-mediated phase separation in the presence of electrolyte as a preconcentration method for cadmium determination by flame atomic absorption spectrometry (FAAS). Cadmium was complexed with ammonium O,O-diethyldithiophosphate (DDTP) in an acidic medium (0.32 mol l- 1 HCl) using Triton X-114 as surfactant and quantitatively extracted into a small volume (about 20 μl) of the surfactant-rich phase after centrifugation. The chemical variables that affect the cloud point extraction, such as complexing time (0 20 min), Triton X114 concentration (0.043 0.87% w/v) and complexing agent concentration (0.01 0.1 mol l- 1), were investigated. The cloud point is formed in the presence of NaCl at room temperature (25 °C), and the electrolyte concentration (0.5 5% w/v) was also investigated. Under optimized conditions, only 8 ml of sample was used in the presence of 0.043% w/v Triton X-114 and 1% (w/v) NaCl. This method permitted limits of detection and quantification of 0.9 μg l- 1 and 2.9 μg l- 1 Cd, respectively, and a linear calibration range from 3 to 400 μg l- 1 Cd. The proposed method was applied to Cd determination in physiological solutions (containing 0.9% (w/v) of NaCl), mineral water, lake water and cigarette samples (tobacco).

  13. Determination of ultra-trace aluminum in human albumin by cloud point extraction and graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sun Mei, E-mail: sunmei@ustc.edu.cn [Hefei National Laboratory for Physical Sciences on Microscale, University of Science and Technology of China, No. 96, Jinzhai Road, Hefei 230026 (China); Wu Qianghua [Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026 (China)

    2010-04-15

    A cloud point extraction (CPE) method for the preconcentration of ultra-trace aluminum in human albumin prior to its determination by graphite furnace atomic absorption spectrometry (GFAAS) had been developed in this paper. The CPE method was based on the complex of Al(III) with 1-(2-pyridylazo)-2-naphthol (PAN) and Triton X-114 was used as non-ionic surfactant. The main factors affecting cloud point extraction efficiency, such as pH of solution, concentration and kind of complexing agent, concentration of non-ionic surfactant, equilibration temperature and time, were investigated in detail. An enrichment factor of 34.8 was obtained for the preconcentration of Al(III) with 10 mL solution. Under the optimal conditions, the detection limit of Al(III) was 0.06 ng mL{sup -1}. The relative standard deviation (n = 7) of sample was 3.6%, values of recovery of aluminum were changed from 92.3% to 94.7% for three samples. This method is simple, accurate, sensitive and can be applied to the determination of ultra-trace aluminum in human albumin.

  14. Determination of total arsenic in coal and wood using oxygen flask combustion method followed by hydride generation atomic absorption spectrometry.

    Science.gov (United States)

    Geng, Wenhua; Furuzono, Takuya; Nakajima, Tsunenori; Takanashi, Hirokazu; Ohki, Akira

    2010-04-15

    A simple and sensitive procedure for the determination of total arsenic in coal and wood was conducted by use of oxygen flask combustion (OFC) followed by hydride generation atomic absorption spectrometry (HGAAS). The effect of various items (composition of absorbent, standing time between the combustion and filtration, particle size and mass of sample) was investigated. Under the optimized conditions of the OFC method, nine certified reference materials were analyzed, and the values of arsenic concentration obtained by this method were in good accordance with the certified values. The limit of detection (LOD) and relative standard deviation (RSD) of the method were 0.29 microg g(-1) and less than 8%, respectively. In addition, eight kinds of coals and four chromated copper arsenate (CCA)-treated wood wastes were analyzed by the present method, and the data were compared to those from the microwave-acid digestion (MW-AD) method. The determination of arsenic in solid samples was discussed in terms of applicable scope and concentration range of arsenic.

  15. Immersed single-drop microextraction-electrothermal vaporization atomic absorption spectroscopy for the trace determination of mercury in water samples.

    Science.gov (United States)

    Bagheri, Habib; Naderi, Mehrnoush

    2009-06-15

    A new method based on single-drop microextraction (SDME) combined with electrothermal vaporization atomic absorption spectroscopy (ETV-AAS) was developed for the trace determination of mercury in water samples. A microdrop of m-xylene was applied as the extraction solvent. After extraction, the microdrop was introduced, directly, into a graphite furnace of AAS. Some important extraction parameters such as type of solvent, volume of solvent, sample stirring, ionic strength, sample pH, chelating agent concentration, sample temperature, and extraction time were investigated and optimized. The highest possible microdrop volume of 10 microL, a sampling temperature of 27 degrees C, and use of m-xylene containing dithizone, as complexing agent, are major parameters led to achieve a high enrichment factor of 970. Under the optimized conditions, the detection limit of the method was 0.01 microg L(-1) and the relative standard deviation was 6.1% (n=7). The proposed method has been successfully applied to the determination of Hg in two river water samples. The effects of interfering species such as Pt, Pd, Cu, Au, and Bi, having the tendency to form complexes with dithizone, at two concentration levels of 100 and 1000 microg L(-1) were also studied.

  16. Determination of platinum and palladium in road dust after their separation on immobilized fungus by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Woinska, Sylwia; Godlewska-Zylkiewicz, Beata, E-mail: bgodlew@uwb.edu.pl

    2011-07-15

    A flow solid phase extraction procedure based on biosorption of Pt(IV) and Pd(II) on Aspergillus sp. immobilized on cellulose resin Cellex-T was proposed for the separation and preconcentration of Pt and Pd before their determination by electrothermal atomic absorption spectrometry (ETAAS). The analytical conditions including sample pH, eluent type, flow rates of sample and eluent solutions were examined. The analytes were selectively retained on the biosorbent in acidic medium (pH 1) and subsequently eluted from the column with 1 mL of thiourea solution (0.25 mol L{sup -1} thiourea in 0.3 mol L{sup -1} HCl). The reproducibility of the procedure was below 5%. The limit of detection of the method was 0.020 ng mL{sup -1} for Pt and 0.012 ng mL{sup -1} for Pd. The method validation was performed by analysis of certified reference materials BCR-723 (tunnel dust) and SARM-76 (platinum ore). The developed separation procedure was applied to the determination of Pt and Pd in road dust samples by ETAAS. The applied biosorbent is characterized by high sorption capacity: 0.47 mg g{sup -1} for Pt and 1.24 mg g{sup -1} for Pd.

  17. Determination of platinum and palladium in road dust after their separation on immobilized fungus by electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Woińska, Sylwia; Godlewska-Żyłkiewicz, Beata

    2011-07-01

    A flow solid phase extraction procedure based on biosorption of Pt(IV) and Pd(II) on Aspergillus sp. immobilized on cellulose resin Cellex-T was proposed for the separation and preconcentration of Pt and Pd before their determination by electrothermal atomic absorption spectrometry (ETAAS). The analytical conditions including sample pH, eluent type, flow rates of sample and eluent solutions were examined. The analytes were selectively retained on the biosorbent in acidic medium (pH 1) and subsequently eluted from the column with 1 mL of thiourea solution (0.25 mol L - 1 thiourea in 0.3 mol L - 1 HCl). The reproducibility of the procedure was below 5%. The limit of detection of the method was 0.020 ng mL - 1 for Pt and 0.012 ng mL - 1 for Pd. The method validation was performed by analysis of certified reference materials BCR-723 (tunnel dust) and SARM-76 (platinum ore). The developed separation procedure was applied to the determination of Pt and Pd in road dust samples by ETAAS. The applied biosorbent is characterized by high sorption capacity: 0.47 mg g - 1 for Pt and 1.24 mg g - 1 for Pd.

  18. Standard test method for graphite furnace atomic absorption spectrometric determination of lead and cadmium extracted from ceramic foodware

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This test method covers procedures for using graphite furnace atomic absorption spectroscopy (GFAAS) to quantitatively determine lead and cadmium extracted by acetic acid at room temperature from the food-contact surface of foodware. The method is applicable to food-contact surfaces composed of silicate-based materials (earthenware, glazed ceramicware, decorated ceramicware, decorated glass, and lead crystal glass) and is capable of determining lead concentrations greater than 0.005 to 0.020 g/mL and cadmium concentrations greater than 0.0005 to 0.002 g/mL, depending on instrument design. 1.2 This test method also describes quality control procedures to check for contamination and matrix interference during GFAAS analyses and a specific sequence of analytical measurements that demonstrates proper instrument operation during the time period in which sample solutions are analyzed. 1.3 Cleaning and other contamination control procedures are described in this test method. Users may modify contamination cont...

  19. Determination of molybdenum in plants by vortex-assisted emulsification solidified floating organic drop microextraction and flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Oviedo, Jenny A.; Fialho, Lucimar L.; Nóbrega, Joaquim A., E-mail: djan@terra.com.br

    2013-08-01

    A fast and sensitive procedure for extraction and preconcentration of molybdenum in plant samples based on solidified floating organic drop microextraction combined with flame atomic absorption spectrometry and discrete nebulization was developed. 8-Hydroxyquinoline (8-HQ) was used as complexing agent. The experimental conditions established were: 0.5% m v{sup −1} of 8-HQ, 60 μL of 1-undecanol as the extractant phase, 2 min vortex extraction time, centrifugation for 2 min at 2000 rpm, 10 min into an ice bath and discrete nebulization by introducing 200 μL of solution. The calibration curve was linear from 0.02 to 4.0 mg L{sup −1} with a limit of detection of 4.9 μg L{sup −1} and an enhancement factor of 67. The relative standard deviations for ten replicate measurements of 0.05 and 1.0 mg L{sup −1} Mo were 6.0 and 14.5%, respectively. The developed procedure was applied for determining molybdenum in corn samples and accuracy was proved using certified reference materials. - Highlights: ► Molybdenum was determined in plants by flame AAS. ► Flame AAS sensitivity was improved using microextraction and discrete nebulization. ► The developed procedure can be easily implemented in routine analysis. ► Green chemistry principles are followed.

  20. Dispersive Liquid-Liquid Microextraction of Bismuth in Various Samples and Determination by Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Teslima Daşbaşı

    2016-01-01

    Full Text Available A dispersive liquid-liquid microextraction method for the determination of bismuth in various samples by flame atomic absorption spectrometry is described. In this method, crystal violet was used as counter positive ion for BiCl4- complex ion, chloroform as extraction solvent, and ethanol as disperser solvent. The analytical parameters that may affect the extraction efficiency like acidity of sample, type and amount of extraction and disperser solvents, amount of ligand, and extraction time were studied in detail. The effect of interfering ions on the analyte recovery was also investigated. The calibration graph was linear in the range of 0.040–1.00 mg L−1 with detection limit of 4.0 μg L−1 (n=13. The precision as relative standard deviation was 3% (n=11, 0.20 mg L−1 and the enrichment factor was 74. The developed method was applied successfully for the determination of bismuth in various water, pharmaceutical, and cosmetic samples and the certified reference material (TMDA-64 lake water.

  1. [Biological material sampling for atomic absorption analysis].

    Science.gov (United States)

    Makarenko, N P; Ganebnykh, E V

    2007-01-01

    The optimum conditions have been chosen for mineralization of biological material for the atomic absorption determination of toxic metals, by using a [Russian characters: see text]-01 laboratory furnace (Gefest) upon exposure to high temperature, pressure, and microwave field. The completeness of dissection of biological material by microwave mineralization is shown under the optimal conditions.

  2. Determination of aluminum by electrothermal atomic absorption spectroscopy in lubricating oils emulsified in a sequential injection analysis system.

    Science.gov (United States)

    Burguera, José L; Burguera, Marcela; Antón, Raquel E; Salager, Jean-Louis; Arandia, María A; Rondón, Carlos; Carrero, Pablo; de Peña, Yaneira Petit; Brunetto, Rosario; Gallignani, Máximo

    2005-12-15

    The sequential injection (SIA) technique was applied for the on-line preparation of an "oil in water" microemulsion and for the determination of aluminum in new and used lubricating oils by electrothermal atomic absorption spectrometry (ET AAS) with Zeeman-effect background correction. Respectively, 1.0, 0.5 and 1.0ml of surfactants mixture, sample and co-surfactant (sec-butanol) solutions were sequentially aspirated to a holding coil. The sonication and repetitive change of the flowing direction improved the stability of the different emulsion types (oil in water, water in oil and microemulsion). The emulsified zone was pumped to fill the sampling arm of the spectrometer with a sub-sample of 200mul. Then, 10mul of this sample solution were introduced by means of air displacement in the graphite tube atomizer. This sequence was timed to synchronize with the previous introduction of 15mug of Mg(NO(3))(2) (in a 10mul) by the spectrometer autosampler. The entire SIA system was controlled by a computer, independent of the spectrometer. The furnace program was carried out by employing a heating cycle in four steps: drying (two steps at 110 and 130 degrees C), pyrolisis (at 1500 degrees C), atomization (at 2400 degrees C) and cleaning (at 2400 degrees C). The calibration graph was linear from 7.7 to 120mugAll(-1). The characteristic mass (mo) was 33.2pg/0.0044s and the detection limit was 2.3mugAll(-1). The relative standard (RSD) of the method, evaluated by replicate analyses of different lubricating oil samples varied in all cases between 1.5 and 1.7%, and the recovery values found in the analysis of spiked samples ranged from 97.2 to 100.4%. The agreement between the observed and reference values obtained from two NIST Standard Certified Materials was good. The method was simple and satisfactory for determining aluminum in new and used lubricating oils.

  3. Direct and combined methods for the determination of chromium, copper, and nickel in honey by electrothermal atomic absorption spectroscopy.

    Science.gov (United States)

    Rodríguez García, J C; Barciela García, J; Herrero Latorre, C; García Martín, S; Peña Crecente, R M

    2005-08-24

    In the present work, direct methods for the determination of chromium, copper, and nickel in honey by electrothermal atomic absorption spectroscopy were developed using experimental design as an optimization tool. Once the optimum conditions for the individual methods were established, a direct method for the combined determination of the three elements was optimized using the response surface tool. Palladium was used as chemical modifier in all cases. Honey was diluted in water, hydrogen peroxide, and nitric acid. Triton X-100 was added to minimize the matrix effect and the viscosity of the sample. The RSD (better than 10%) and the analytical recovery (98-103%) were acceptable for all of the developed methods. Calibration graphs were used in the four methods to determine the concentration of the analytes in the sample. The detection limits of the combined method (0.21, 0.35, and 0.37 microg L(-)(1) for Cr, Cu, and Ni, respectively) were similar to those obtained for the individual methods (LOD = 0.17, 0.21, 0.33 microg L(-)(1) for Cr, Cu, and Ni, respectively). The direct-combined proposed method has been applied to the determination of chromium, copper, and nickel content in representative honey samples from Galicia (northwestern Spain). The concentrations found in the analyzed samples were in the range of (5.75 +/- 0.64)-(26.4 +/- 0.38) ng g(-)(1) of Cr, (79 +/- 7.8)-(2049 +/- 80) ng g(-)(1) of Cu, and (12.6 +/- 1.36)-(172 +/- 6.88) ng g(-)(1) of Ni.

  4. Determination of trace nickel in hydrogenated cottonseed oil by electrothermal atomic absorption spectrometry after microwave-assisted digestion.

    Science.gov (United States)

    Zhang, Gai

    2012-01-01

    Microwave digestion of hydrogenated cottonseed oil prior to trace nickel determination by electrothermal atomic absorption spectrometry (ETAAS) is proposed here for the first time. Currently, the methods outlined in U.S. Pharmacopeia 28 (USP28) or British Pharmacopeia (BP2003) are recommended as the official methods for analyzing nickel in hydrogenated cottonseed oil. With these methods the samples may be pre-treated by a silica or a platinum crucible. However, the samples were easily tarnished during sample pretreatment when using a silica crucible. In contrast, when using a platinum crucible, hydrogenated cottonseed oil acting as a reducing material may react with the platinum and destroy the crucible. The proposed microwave-assisted digestion avoided tarnishing of sample in the process of sample pretreatment and also reduced the cycle of analysis. The programs of microwave digestion and the parameters of ETAAS were optimized. The accuracy of the proposed method was investigated by analyzing real samples. The results were compared with the ones by pressurized-PTFE-bomb acid digestion and ones obtained by the U.S. Pharmacopeia 28 (USP28) method. The new method involves a relatively rapid matrix destruction technique compared with other present methods for the quantification of metals in oil.

  5. Cloud point extraction for the determination of copper, nickel and cobalt ions in environmental samples by flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ghaedi, M. [Chemistry Department, University of Yasouj, Yasouj 75914-353 (Iran, Islamic Republic of)], E-mail: m_ghaedi@mail.yu.ac.ir; Shokrollahi, A.; Ahmadi, F.; Rajabi, H.R. [Chemistry Department, University of Yasouj, Yasouj 75914-353 (Iran, Islamic Republic of); Soylak, M. [Chemistry Department, University of Erciyes, 38039 Kayseri (Turkey)

    2008-02-11

    A cloud point extraction procedure was presented for the preconcentration of copper, nickel and cobalt ions in various samples. After complexation with methyl-2-pyridylketone oxime (MPKO) in basic medium, analyte ions are quantitatively extracted to the phase rich in Triton X-114 following centrifugation. 1.0 mol L{sup -1} HNO{sub 3} nitric acid in methanol was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The adopted concentrations for MPKO, Triton X-114 and HNO{sub 3}, bath temperature, centrifuge rate and time were optimized. Detection limits (3 SDb/m) of 1.6, 2.1 and 1.9 ng mL{sup -1} for Cu{sup 2+}, Co{sup 2+} and Ni{sup 2+} along with preconcentration factors of 30 and for these ions and enrichment factor of 65, 58 and 67 for Cu{sup 2+}, Ni{sup 2+} and Co{sup 2+}, respectively. The high efficiency of cloud point extraction to carry out the determination of analytes in complex matrices was demonstrated. The proposed procedure was applied to the analysis of biological, natural and wastewater, soil and blood samples.

  6. Cloud point extraction-flame atomic absorption spectrometry method for preconcentration and determination of trace cadmium in water samples.

    Science.gov (United States)

    Ning, Jinyan; Jiao, Yang; Zhao, Jiao; Meng, Lifen; Yang, Yaling

    2014-01-01

    A method based on cloud point extraction (CPE) separation/preconcentration of trace cadmium (Cd) as a prior step to its determination by flame atomic absorption spectrometry has been developed. Cadmium reacted with 8-hydroxyquinoline to form hydrophobic chelates, which were extracted into the micelles of nonionic surfactant oligoethylene glycol monoalkyl ether (Genapol X-080) in an alkaline medium. Octanol was used to depress the cloud point of Genapol X-080 in the extraction process. The chemical variables that affect the CPE, such as pH of complexation reaction, amount of chelating agent, Genapol X-080 and octanol were evaluated and optimized. Under optimized conditions, linearity was obeyed in the range of 10-500 μg/L, with the correlation coefficient of 0.9993. For 5 mL of sample solution, the enhancement factor was about 20. The limit of detection and limit of quantification of the method were 0.21 and 0.63 μg/L, respectively. The relative standard deviations (n = 6) was 3.2% for a solution containing 100 μg/L of Cd. The accuracy of the preconcentration system was evaluated by recovery measurements on spiked water samples. Recoveries of spiked samples varied in the range of 94.1-103.8%.

  7. Preconcentration and determination of zinc and lead ions by a combination of cloud point extraction and flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tavallali, H. [Chemistry Department, Payamenore University, Shiraz (Iran); Shokrollahi, A.; Zahedi, M. [Chemistry Department, Yasouj University, Yasouj (Iran); Niknam, K. [Chemistry Department, Persian Gulf University, Bushehr (Iran); Soylak, M. [Chemistry Department, University of Erciyes, Kayseri (Turkey); Ghaedi, M.

    2009-04-15

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of lead(II) and zinc(II). After complexation with 3-[(4-bromophenyl) (1-H-inden-3-yl)methyl]-1 H-indene (BPIMI), the analytes were quantitatively extracted to a phase rich in Triton X-114 after centrifugation. Methanol acidified with 1 mol/L HNO{sub 3} was added to the surfactant rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The concentration of bis((1H-benzo [d] imidazol-2yl)ethyl)sulfane, Triton X-114, pH and amount of surfactant were all optimized. Detection limits (3 SDb/m) of 2.5 and 1.6 ng/mL for Pb{sup 2+} and Zn{sup 2+} along with preconcentration factors of 30 and an enrichment factor of 32 and 48 for Pb{sup 2+}and Zn {sup 2+} ions were obtained, respectively. The proposed cloud point extraction was been successfully applied for the determination of these ions in real samples with complicated matrices such as food and soil samples, with high efficiency. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  8. The determination of wear metals in used lubricating oils by flame atomic absorption spectrometry using sulphanilic acid as ashing agent.

    Science.gov (United States)

    Ekanem, E J; Lori, J A; Thomas, S A

    1997-11-01

    A simple and reliable ashing procedure is proposed for the preparation of used lubricating oil samples for the determination of calcium, magnesium, zinc, iron, chromium and nickel by flame atomic absorption spectrometry. Sulphanilic acid was added to oil samples and the mixture coked and the coke ashed at 550 degrees C. The solutions of the ash were analysed by flame AAS for the metals. The release of calcium, zinc, iron and chromium was improved by the addition of sulphanilic acid to samples. The relative standard deviations of metal concentration results in the initial oil samples were 1.5% for Ca (1500 mg l(-1) level), 0.3% for Mg (100 mg l(-1) level), 3.1% for Zn (1500 mg l(-1) level), 0.7% for Fe (500 mg l(-1) level), 0.02% for Cr (50 mg l(-1) level) and 0.002% for Ni (10 mg l(-1) level). The optimum sample size for efficient metal release was 20 g while the optimum sulphanilic acid to oil ratio was 0.05 g per gram of oil for Zn and Cr and 0.10 g for Ca and Fe. Results obtained by this procedure were highly reproducible and comparable with those obtained for the same samples using standard procedures.

  9. Cloud point extraction for the determination of copper, nickel and cobalt ions in environmental samples by flame atomic absorption spectrometry.

    Science.gov (United States)

    Ghaedi, M; Shokrollahi, A; Ahmadi, F; Rajabi, H R; Soylak, M

    2008-02-11

    A cloud point extraction procedure was presented for the preconcentration of copper, nickel and cobalt ions in various samples. After complexation with methyl-2-pyridylketone oxime (MPKO) in basic medium, analyte ions are quantitatively extracted to the phase rich in Triton X-114 following centrifugation. 1.0 mol L(-1) HNO(3) nitric acid in methanol was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The adopted concentrations for MPKO, Triton X-114 and HNO(3), bath temperature, centrifuge rate and time were optimized. Detection limits (3 SDb/m) of 1.6, 2.1 and 1.9 ng mL(-1) for Cu(2+), Co(2+) and Ni(2+) along with preconcentration factors of 30 and for these ions and enrichment factor of 65, 58 and 67 for Cu(2+), Ni(2+) and Co(2+), respectively. The high efficiency of cloud point extraction to carry out the determination of analytes in complex matrices was demonstrated. The proposed procedure was applied to the analysis of biological, natural and wastewater, soil and blood samples.

  10. Determination of heavy metal contents by atomic absorption spectroscopy (AAS) in some medicinal plants from Pakistani and Malaysian origin.

    Science.gov (United States)

    Akram, Sobia; Najam, Rahila; Rizwani, Ghazala H; Abbas, Syed Atif

    2015-09-01

    This study depicts a profile of existence of heavy metals (Cu, Ni, Zn, Cd, Hg, Mn, Fe, Na, Ca, and Mg) in some important herbal plants like (H. Integrifolia, D. regia, R. communis, C. equisetifolia, N. oleander, T. populnea, M. elengi, H. schizopetalus, P. pterocarpum) from Pakistan and an antidiabetic Malaysian herbal drug product containing (Punica granatum L. (Mast) Hook, Momordica charantia L., Tamarindus indica L., Lawsonia inermis L.) using atomic absorption spectrophotometer. Heavy metals in these herbal plants and Malaysian product were in the range of 0.02-0.10 ppm of Cu, 0.00-0.02 ppm of Ni, 0.02-0.29 ppm of Zn, 0.00-0.04 ppm of Cd, 0.00-1.33 ppm of Hg, 0.00-0.54 ppm of Mn, 0.22-3.16 ppm of Fe, 0.00-9.17 ppm of Na, 3.27-15.63 ppm of Ca and 1.85-2.03 ppm of Mg. All the metals under study were within the prescribed limits except mercury. Out of 10 medicinal plants/product under study 07 were beyond the limit of mercury permissible limits. Purpose of this study is to determine heavy metals contents in selected herbal plants and Malaysian product, also to highlight the health concerns related to the presence of toxic levels of heavy metals.

  11. Sequential injection ionic liquid dispersive liquid-liquid microextraction for thallium preconcentration and determination with flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Anthemidis, Aristidis N.; Ioannou, Kallirroy-Ioanna G. [Aristotle University, Laboratory of Analytical Chemistry, Department of Chemistry, Thessaloniki (Greece)

    2012-08-15

    A novel, automatic on-line sequential injection dispersive liquid-liquid microextraction (SI-DLLME) method, based on 1-hexyl-3-methylimidazolium hexafluorophosphate ([Hmim][PF{sub 6}]) ionic liquid as an extractant solvent was developed and demonstrated for trace thallium determination by flame atomic absorption spectrometry. The ionic liquid was on-line fully dispersed into the aqueous solution in a continuous flow format while the TlBr{sub 4} {sup -} complex was easily migrated into the fine droplets of the extractant due to the huge contact area of them with the aqueous phase. Furthermore, the extractant was simply retained onto the surface of polyurethane foam packed into a microcolumn. No specific conditions like low temperature are required for extractant isolation. All analytical parameters of the proposed method were investigated and optimized. For 15 mL of sample solution, an enhancement factor of 290, a detection limit of 0.86 {mu}g L{sup -1} and a precision (RSD) of 2.7% at 20.0 {mu}g L{sup -1} Tl(I) concentration level, was obtained. The developed method was evaluated by analyzing certified reference materials while good recoveries from environmental and biological samples proved that present method was competitive in practical applications. (orig.)

  12. On-line preconcentration of copper as its pyrocatechol violet complex on Chromosorb 105 for flame atomic absorption spectrometric determinations

    Energy Technology Data Exchange (ETDEWEB)

    Buke, Berrin [Chemistry Department, Science and Arts Faculty, Pamukkale University, 20020 Denizli (Turkey); Divrikli, Umit [Chemistry Department, Science and Arts Faculty, Pamukkale University, 20020 Denizli (Turkey)], E-mail: udivrikli@pamukkale.edu.tr; Soylak, Mustafa [Chemistry Department, Science and Arts Faculty, Erciyes University, 38039 Kayseri (Turkey); Elci, Latif [Chemistry Department, Science and Arts Faculty, Pamukkale University, 20020 Denizli (Turkey)

    2009-04-30

    An on-line solid phase extraction method for the preconcentration and determination of Cu(II) by flame atomic absorption spectrometry (FAAS) has been described. It is based on the adsorption of copper(II) ion onto a home made mini column of Chromosorb 105 resin loaded with pyrocatechol violet at the pH range of 5.0-8.0, then eluted with 1 mol L{sup -1} HNO{sub 3}. Several parameters, such as pH of the sample solution, amount of Chromosorb 105 resin, volume of sample and eluent, type of eluent, flow rates of sample and eluent, governing the efficiency and throughput of the method were evaluated. The concentration of the copper ion detected after preconcentration was in agreement with the added amount. At optimized conditions, for 15 min of preconcentration time (30 mL of sample volume), the system achieved a detection limit of 0.02 {mu}g L{sup -1}, with relative standard deviation 1.1% at 0.03 {mu}g mL{sup -1} copper. The present method was found to be applicable to the preconcentration of Cu(II) in natural water samples.

  13. Separation and enrichment of gold(III) from environmental samples prior to its flame atomic absorption spectrometric determination

    Energy Technology Data Exchange (ETDEWEB)

    Senturk, Hasan Basri; Gundogdu, Ali [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Bulut, Volkan Numan [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 28049 Giresun (Turkey); Duran, Celal [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Soylak, Mustafa [Department of Chemistry, Faculty of Arts and Sciences, Erciyes University, 38039 Kayseri (Turkey)], E-mail: soylak@erciyes.edu.tr; Elci, Latif [Department of Chemistry, Faculty of Arts and Sciences, Pamukkale University, 20020 Denizli (Turkey); Tufekci, Mehmet [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey)

    2007-10-22

    A simple and accurate method was developed for separation and enrichment of trace levels of gold in environmental samples. The method is based on the adsorption of Au(III)-diethyldithiocarbamate complex on Amberlite XAD-2000 resin prior to the analysis of gold by flame atomic absorption spectrometry after elution with 1 mol L{sup -1} HNO{sub 3} in acetone. Some parameters including nitric acid concentration, eluent type, matrix ions, sample volume, sample flow rate and adsorption capacity were investigated on the recovery of gold(III). The recovery values for gold(III) and detection limit of gold were greater than 95% and 16.6 {mu}g L{sup -1}, respectively. The preconcentration factor was 200. The relative standard deviation of the method was <6%. The adsorption capacity of the resin was 12.3 mg g{sup -1}. The validation of the presented procedure was checked by the analysis of CRM-SA-C Sandy Soil certified reference material. The presented procedure was applied to the determination of gold in some environmental samples.

  14. Determination of Fe Content of Some Food Items by Flame Atomic Absorption Spectroscopy (FAAS): A Guided-Inquiry Learning Experience in Instrumental Analysis Laboratory

    Science.gov (United States)

    Fakayode, Sayo O.; King, Angela G.; Yakubu, Mamudu; Mohammed, Abdul K.; Pollard, David A.

    2012-01-01

    This article presents a guided-inquiry (GI) hands-on determination of Fe in food samples including plantains, spinach, lima beans, oatmeal, Frosted Flakes cereal (generic), tilapia fish, and chicken using flame atomic absorption spectroscopy (FAAS). The utility of the GI experiment, which is part of an instrumental analysis laboratory course,…

  15. International comparison of Cd content in a quality control material of Navajuelas (Tagelus dombeii) determined by anodic stripping voltammetry, atomic absorption spectrometry and neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Queirolo, F. (Universidad Catolica del Norte, Antofagasta (Chile). Dept. of Chemistry Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie Universidad de Extremadura, Badajoz (Spain). Dept. of Analytical Chemistry and Electrochemistry); Ostapczuk, P. (Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie); Valenta, P.; Stegen, S. (Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie Universidad de Extremadura, Badajoz (Spain). Dept. of Analytical Chemistry and Electrochemistry); Marin, C.; Vinagre, F.; Sanchez, A. (Universidad de Extremadura, Badajoz (Spain). Dept. of Analytical Chemistry and Electrochemistry)

    1991-05-01

    The determination of Cd was performed by neutron activation analysis (NAA), atomic absorption spectrometry (AAS) with flame or in the electrothermal mode and anodic stripping voltammetry in the differential pulse mode (DPASV) and the square wave mode (SWASV). (orig./EF).

  16. Trace element determination-I Use of 2,9-dimethyl-1,10-phenanthroline in determination of copper in heavy matrices by carbon furnace atomic-absorption spectrometry.

    Science.gov (United States)

    Battistoni, P; Bruni, P; Cardellini, L; Fava, G; Gobbi, G

    1980-08-01

    A method for the determination of copper in complex matrices by electrothermal atomic-absorption spectrometry has been developed. It uses neocuproine as complexing agent. The detection limit is 0.2 ng/ml, and interferences are minimized.

  17. Metastable argon atom density in complex argon/acetylene plasmas determined by means of optical absorption and emission spectroscopy

    Science.gov (United States)

    Sushkov, Vladimir; Herrendorf, Ann-Pierra; Hippler, Rainer

    2016-10-01

    Optical emission and absorption spectroscopy has been utilized to investigate the instability of acetylene-containing dusty plasmas induced by growing nano-particles. The density of Ar(1s5) metastable atoms was derived by two methods: tunable diode laser absorption spectroscopy and with the help of the branching ratio method of emitted spectral lines. Results of the two techniques agree well with each other. The density of Ar(1s3) metastable atoms was also measured by means of optical emission spectroscopy. The observed growth instability leads to pronounced temporal variations of the metastable and other excited state densities. An analysis of optical line ratios provides evidence for a depletion of free electrons during the growth cycle but no indication for electron temperature variations.

  18. Determination of ultra trace arsenic species in water samples by hydride generation atomic absorption spectrometry after cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Ulusoy, Halil Ibrahim, E-mail: hiulusoy@yahoo.com [University of Cumhuriyet, Faculty of Science, Department of Chemistry, TR-58140, Sivas (Turkey); Akcay, Mehmet; Ulusoy, Songuel; Guerkan, Ramazan [University of Cumhuriyet, Faculty of Science, Department of Chemistry, TR-58140, Sivas (Turkey)

    2011-10-10

    Graphical abstract: The possible complex formation mechanism for ultra-trace As determination. Highlights: {yields} CPE/HGAAS system for arsenic determination and speciation in real samples has been applied first time until now. {yields} The proposed method has the lowest detection limit when compared with those of similar CPE studies present in literature. {yields} The linear range of the method is highly wide and suitable for its application to real samples. - Abstract: Cloud point extraction (CPE) methodology has successfully been employed for the preconcentration of ultra-trace arsenic species in aqueous samples prior to hydride generation atomic absorption spectrometry (HGAAS). As(III) has formed an ion-pairing complex with Pyronine B in presence of sodium dodecyl sulfate (SDS) at pH 10.0 and extracted into the non-ionic surfactant, polyethylene glycol tert-octylphenyl ether (Triton X-114). After phase separation, the surfactant-rich phase was diluted with 2 mL of 1 M HCl and 0.5 mL of 3.0% (w/v) Antifoam A. Under the optimized conditions, a preconcentration factor of 60 and a detection limit of 0.008 {mu}g L{sup -1} with a correlation coefficient of 0.9918 was obtained with a calibration curve in the range of 0.03-4.00 {mu}g L{sup -1}. The proposed preconcentration procedure was successfully applied to the determination of As(III) ions in certified standard water samples (TMDA-53.3 and NIST 1643e, a low level fortified standard for trace elements) and some real samples including natural drinking water and tap water samples.

  19. Coacervative extraction of trace lead from natural waters prior to its determination by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hagarová, Ingrid, E-mail: hagarova@fns.uniba.sk; Bujdoš, Marek; Matúš, Peter; Kubová, Jana

    2013-10-01

    In this work, a relatively simple and sensitive method for separation/preconcentration of trace lead from natural waters prior to its determination by electrothermal atomic absorption spectrometry has been proposed. The method is based on the extraction of Pb–dithizone chelate with coacervates made up of lauric acid in the presence of potassium ions and methanol. Several important factors affecting extraction efficiency such as pH, concentration of lauric acid and dithizone, ionic strength, incubation and centrifugation time were investigated and optimized. After separation of aqueous bulk solution from surfactant-rich phase, the final extract was redissolved by using 500 μl of methanol acidified with 0.2 mol l{sup −1} HNO{sub 3}. Under the optimized conditions (using initial sample volume of 10 ml), enrichment factor of 17.0, detection limit of 0.12 μg l{sup −1}, quantification limit of 0.38 μg l{sup −1}, relative standard deviation of 4.2% (for 2 μg l{sup −1} of Pb; n = 26), linearity of the calibration graph in the range of 0.5–4.0 μg l{sup −1} (with correlation coefficient better than 0.995) were achieved. The method was validated by the analysis of certified reference material (TMDA-61). Extraction recoveries for the CRM, spiked model solutions and spiked natural water samples were in the range of 91–96%. Finally, the method was applied to the separation/preconcentration and determination of trace lead in natural waters. - Highlights: • The potential of coacervates for the extraction of metal ions is examined. • No difficulties in coupling of ETAAS with the proposed CAE are observed. • Achieved preconcentration factor results in enhanced sensitivity. • Analytical performance is confirmed by the reliable determination of trace Pb. • The proposed CAE is ecofriendly and efficient.

  20. Preconcentration procedure using cloud point extraction in the presence of electrolyte for cadmium determination by flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Melo Coelho, Luciana [Departamento de Quimica Analitica, Universidade Estadual de Campinas (Unicamp), Cidade Universitaria ' Zeferino Vaz' , 13084-971, Campinas, Sao Paulo (Brazil); Arruda, Marco Aurelio Zezzi [Departamento de Quimica Analitica, Universidade Estadual de Campinas (Unicamp), Cidade Universitaria ' Zeferino Vaz' , 13084-971, Campinas, Sao Paulo (Brazil)]. E-mail: zezzi@iqm.unicamp.br

    2005-06-30

    This paper describes a micelle-mediated phase separation in the presence of electrolyte as a preconcentration method for cadmium determination by flame atomic absorption spectrometry (FAAS). Cadmium was complexed with ammonium O,O-diethyldithiophosphate (DDTP) in an acidic medium (0.32 mol l{sup -} {sup 1} HCl) using Triton X-114 as surfactant and quantitatively extracted into a small volume (about 20 {mu}l) of the surfactant-rich phase after centrifugation. The chemical variables that affect the cloud point extraction, such as complexing time (0-20 min), Triton X114 concentration (0.043-0.87% w/v) and complexing agent concentration (0.01-0.1 mol l{sup -} {sup 1}), were investigated. The cloud point is formed in the presence of NaCl at room temperature (25 deg. C), and the electrolyte concentration (0.5-5% w/v) was also investigated. Under optimized conditions, only 8 ml of sample was used in the presence of 0.043% w/v Triton X-114 and 1% (w/v) NaCl. This method permitted limits of detection and quantification of 0.9 {mu}g l{sup -} {sup 1} and 2.9 {mu}g l{sup -} {sup 1} Cd, respectively, and a linear calibration range from 3 to 400 {mu}g l{sup -} {sup 1} Cd. The proposed method was applied to Cd determination in physiological solutions (containing 0.9% (w/v) of NaCl), mineral water, lake water and cigarette samples (tobacco)

  1. Simultaneous flow injection preconcentration of lead and cadmium using cloud point extraction and determination by atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Edson Luiz [Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario, 303, CP 96, 13416-000 Piracicaba, SP (Brazil)], E-mail: edsonqmc@hotmail.com; Santos Roldan, Paulo dos [Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario, 303, CP 96, 13416-000 Piracicaba, SP (Brazil)

    2009-01-15

    A flow injection (FI) micelle-mediated separation/preconcentration procedure for the determination of lead and cadmium by flame atomic absorption spectrometry (FAAS) has been proposed. The analytes reacted with 1-(2-thiazolylazo)-2-naphthol (TAN) to form hydrophobic chelates, which were extracted into the micelles of 0.05% (w/v) Triton X-114 in a solution buffered at pH 8.4. In the preconcentration stage, the micellar solution was continuously injected into a flow system with four mini-columns packed with cotton, glass wool, or TNT compresses for phase separation. The analytes-containing micelles were eluted from the mini-columns by a stream of 3 mol L{sup -1} HCl solution and the analytes were determined by FAAS. Chemical and flow variables affecting the preconcentration of the analytes were studied. For 15 mL of preconcentrated solution, the enhancement factors varied between 15.1 and 20.3, the limits of detection were approximately 4.5 and 0.75 {mu}g L{sup -1} for lead and cadmium, respectively. For a solution containing 100 and 10 {mu}g L{sup -1} of lead and cadmium, respectively, the R.S.D. values varied from 1.6 to 3.2% (n = 7). The accuracy of the preconcentration system was evaluated by recovery measurements on spiked water samples. The method was susceptible to matrix effects, but these interferences were minimized by adding barium ions as masking agent in the sample solutions, and recoveries from spiked sample varied in the range of 95.1-107.3%.

  2. Determination of calcium, magnesium and zinc in lubricating oils by flame atomic absorption spectrometry using a three-component solution.

    Science.gov (United States)

    Zmozinski, Ariane V; de Jesus, Alexandre; Vale, Maria G R; Silva, Márcia M

    2010-12-15

    Lubricating oils are used to decrease wear and friction of movable parts of engines and turbines, being in that way essential for the performance and the increase of that equipment lifespan. The presence of some metals shows the addition of specific additives such as detergents, dispersals and antioxidants that improve the performance of these lubricants. In this work, a method for determination of calcium, magnesium and zinc in lubricating oil by flame atomic absorption spectrometry (F AAS) was developed. The samples were diluted with a small quantity of aviation kerosene (AVK), n-propanol and water to form a three-component solution before its introduction in the F AAS. Aqueous inorganic standards diluted in the same way have been used for calibration. To assess the accuracy of the new method, it was compared with ABNT NBR 14066 standard method, which consists in diluting the sample with AVK and in quantification by F AAS. Two other validating methods have also been used: the acid digestion and the certified reference material NIST (SRM 1084a). The proposed method provides the following advantages in relation to the standard method: significant reduction of the use of AVK, higher stability of the analytes in the medium and application of aqueous inorganic standards for calibration. The limits of detection for calcium, magnesium and zinc were 1.3 μg g(-1), 0.052 μg g(-1) and 0.41 μg g(-1), respectively. Concentrations of calcium, magnesium and zinc in six different samples obtained by the developed method did not differ significantly from the results obtained by the reference methods at the 95% confidence level (Student's t-test and ANOVA). Therefore, the proposed method becomes an efficient alternative for determination of metals in lubricating oil.

  3. Simple decomposition procedure for determination of selenium in whole blood, serum and urine by hydride generation atomic absorption spectroscopy.

    Science.gov (United States)

    Tiran, B; Tiran, A; Rossipal, E; Lorenz, O

    1993-12-01

    A digestion procedure for selenium determination by hydride generation atomic absorption spectroscopy (AAS) in whole blood, serum and urine is described, it employs sulfuric acid, hydrogen peroxide and vanadium (V) sulfuric acid reagent solution. The method is rapid, uses no explosive reagents and can be performed at a constant temperature of 100 degrees C. Therefore, it is easily applicable in a routine clinical laboratory for a large amount of samples. The coefficient of intra-assay variation was 4.3-5.6%, the coefficient for inter-assay variation was 5-5.9% in the medium and high concentration range, and 5.8-8.6% in the low range. In analyzing several commercial reference materials our results showed good agreement with the target values. Analytical recovery by addition of sodium selenite and seleno-DL-methionine to samples ranged between 97 and 104%. The correlation between the described digestion procedure and the nitric, sulfuric and perchloric acid digestion procedure recommended by the International Union of Pure and Applied Chemistry showed good agreement for whole blood, serum and for urine. We determined selenium in serum (n = 58) and whole blood (n = 50) in a collective of healthy children from 1 to 5 years living in Styria, Austria. The low values in serum (35 +/- 11 micrograms/L) and whole blood (42 +/- 6 micrograms/L) at one year of life increased significantly to 48 +/- 13 mu/L (p = 0.033) and 55 +/- 6 micrograms/L (p = 0.004) at three years of life in serum and whole blood, respectively. The selenium concentration showed no further increase up to five years of age.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Selective cloud point extraction and graphite furnace atomic absorption spectrometric determination of molybdenum (VI) ion in seawater samples

    Energy Technology Data Exchange (ETDEWEB)

    Filik, Hayati, E-mail: filik@istanbul.edu.tr [Istanbul University, Faculty of Engineering, Department of Chemistry, Avcilar, 34320 Istanbul (Turkey); Cengel, Tayfun; Apak, Resat [Istanbul University, Faculty of Engineering, Department of Chemistry, Avcilar, 34320 Istanbul (Turkey)

    2009-09-30

    A cloud point extraction process using the nonionic surfactant Triton X-114 to extract molybdenum from aqueous solutions was investigated. The method is based on the complexation reaction of Mo(VI) with 1,2,5,8-tetrahydroxyanthracene-9,10-dione (quinalizarine: QA) and micelle-mediated extraction of the complex. The enriched analyte in the surfactant-rich phase was determined by graphite furnace atomic absorption spectrometry (GFAAS). The optimal extraction and reaction conditions (e.g. pH, reagent and surfactant concentrations, temperature, incubation and centrifugation times) were evaluated and optimized. Under the optimized experimental conditions, the limit of detection (LOD) for Mo(VI) was 7.0 ng L{sup -1} with an preconcentration factor of {approx}25 when 10 mL of sample solution was preconcentrated to 0.4 mL. The proposed method (with extraction) showed linear calibration within the range 0.03-0.6 {mu}g L{sup -1}. The relative standard deviation (RSD) was found to be 3.7% (C{sub Mo(VI)} = 0.05 {mu}g L{sup -1}, n = 5) for pure standard solutions, whereas RSD for the recoveries from real samples ranged between 2 and 8% (mean RSD = 3.9%). The method was applied to the determination of Mo(VI) in seawater and tap water samples with a recovery for the spiked samples in the range of 98-103%. The interference effect of some cations and anions was also studied. In the presence of foreign ions, no significant interference was observed. In order to verify the accuracy of the method, a certified reference water sample was analysed and the results obtained were in good agreement with the certified values.

  5. The determination of low lead levels in the bone of lead-depleted mice by graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Iavicoli, I.; Carelli, G.; Castellino, N. [Univ. Cattolica del Sacro Cuore, Roma (Italy). Inst. of Occupational Health; Schlemmer, G. [Bodenseewerk Perkin-Elmer und Co. GmbH, Ueberlingen (Germany)

    2001-08-01

    Low lead levels in the femurs of mice fed with a lead-depleted diet have been determined by use of electrothermal atomic absorption spectrometry with Zeeman-effect background correction. The method is based on the use of Mg(NO{sub 3}){sub 2}/Pd as matrix modifier which enables significant reduction of the spectral interferences prevalent if chemical modifiers based on NH{sub 4}H{sub 2}PO{sub 4} with either Ca or Mg are used for samples rich in Ca{sub 3}(PO{sub 4}){sub 2} matrix. The method was developed and validated by use of the NIST standard reference material 1486 bone. Bones were decomposed in a pressurized microwave-heated system using 70% nitric acid. Forty-three mice femurs, with a mass of 74.62 {+-} 12.54 mg, were dissolved in concentrated nitric acid. The lead results found in SRM 1486 (1.25 {+-} 0.15 {mu}g g{sup -1}, n = 9) were in good agreement with the certificate (1.335 {+-} 0.014 {mu}g g{sup -1}). Recoveries of 200 ng lead added to the SRM before or after digestion were 99.0 {+-} 1.4% and 98.5 {+-} 1.6%, respectively. The lead detection limit in bone samples is 0.06 {mu}g g{sup -1} dry mass. This method is, therefore, suitable for the determination of very low lead levels (0.06-0.20 {mu}g Pb kg{sup -1} bone) in the femurs of mice fed a diet with lead level of < 20 {mu}g kg{sup -1}. (orig.)

  6. Coacervative extraction of trace lead from natural waters prior to its determination by electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Hagarová, Ingrid; Bujdoš, Marek; Matúš, Peter; Kubová, Jana

    2013-10-01

    In this work, a relatively simple and sensitive method for separation/preconcentration of trace lead from natural waters prior to its determination by electrothermal atomic absorption spectrometry has been proposed. The method is based on the extraction of Pb-dithizone chelate with coacervates made up of lauric acid in the presence of potassium ions and methanol. Several important factors affecting extraction efficiency such as pH, concentration of lauric acid and dithizone, ionic strength, incubation and centrifugation time were investigated and optimized. After separation of aqueous bulk solution from surfactant-rich phase, the final extract was redissolved by using 500 μl of methanol acidified with 0.2 mol l- 1 HNO3. Under the optimized conditions (using initial sample volume of 10 ml), enrichment factor of 17.0, detection limit of 0.12 μg l- 1, quantification limit of 0.38 μg l- 1, relative standard deviation of 4.2% (for 2 μg l- 1 of Pb; n = 26), linearity of the calibration graph in the range of 0.5-4.0 μg l- 1 (with correlation coefficient better than 0.995) were achieved. The method was validated by the analysis of certified reference material (TMDA-61). Extraction recoveries for the CRM, spiked model solutions and spiked natural water samples were in the range of 91-96%. Finally, the method was applied to the separation/preconcentration and determination of trace lead in natural waters.

  7. Evaluation of lithium determination in three analyzers: flame emission, flame atomic absorption spectroscopy and ion selective electrode

    Directory of Open Access Journals (Sweden)

    Mehri Aliasgharpour

    2009-10-01

    Full Text Available Background: Lithium carbonate salt has become an increasingly important substance in the treatment of manic depressive disorders, and its relatively narrow therapeutic range has caused laboratories to monitor the serum concentration carefully. In the present work we evaluated lithium measurement in 3 different analyzers. Methods & Materials: Three different analyzers including Flame Emission (FES, Flame Atomic Absorption Spectroscopy (FAAS, and Ion Selective Electrode (ISE were used. All chemicals had a grade suitable for trace metal analysis. Results: Within-day precision of CV was ≤ 1.5% for FES & FAAS, except for ISE (1.9% CV. Between-days precision of CV was less for FES than for FAAS and ISE (1.3% versus 2.2% & 2.3%. The percent recovery of added lithium in pooled patients’ serum was higher for ISE than for FASS and FES (103.4% versus 96.2% and 94.6%. We also obtained a higher average lithium concentration for patients’ serum samples (n=16 measured by ISE than for FAAS and FES (0.825±0.30 versus 0.704±0.26 & 0.735±0.19. Paired t-test results revealed a significant difference (p< 0.001 for patient sera analyzed with FAAS and ISE. Conclusion: We report higher results for ISE than the other two analyzers and conclude that the choice between the two flame methods for patients’ serum lithium determination is arbitrary and that FES analyzer is a more attractive routine alternative for lithium determination than FAAS because of its cost and ease of performance. In addition, the results obtained by ISE are precise. However, its accuracy may depend on other interfering factors.

  8. Preconcentration of gold ions from water samples by modified organo-nanoclay sorbent prior to flame atomic absorption spectrometry determination

    Energy Technology Data Exchange (ETDEWEB)

    Afzali, Daryoush, E-mail: daryoush_afzali@yahoo.com [Nanochemistry Department, Research Institute of Environmental Sciences, International Center for Science, High Technology and Environmental Sciences, Kerman (Iran, Islamic Republic of); Mostafavi, Ali [Chemistry Department, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Mirzaei, Mohammad [Nanochemistry Department, Research Institute of Environmental Sciences, International Center for Science, High Technology and Environmental Sciences, Kerman (Iran, Islamic Republic of); Chemistry Department, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of)

    2010-09-15

    In this work, the applicability of modified organo nanoclay as a new and easy prepared solid sorbent for the preconcentration of trace amounts of Au(III) ion from water samples is studied. The organo nanoclay was modified with 5-(4'-dimethylamino benzyliden)-rhodanine and used as a sorbent for separation of Au(III) ions. The sorption of gold ions was quantitative in the pH range of 2.0-6.0. Quantitative desorption occurred with 6.0 mL of 1.0 mol L{sup -1} Na{sub 2}S{sub 2}O{sub 3}. The amount of eluted Au(III) was measured using flame atomic absorption spectrometry. In the initial solution the linear dynamic range was in the range of 0.45 ng mL{sup -1} to 10.0 {mu}g mL{sup -1}, the detection limit was 0.1 ng mL{sup -1} and the preconcentration factor was 105. Also, the relative standard deviation was {+-}2.3% (n = 8 and C = 2.0 {mu}g mL{sup -1}) and the maximum capacity of the sorbent was 3.9 mg of Au(III) per gram of modified organo nanoclay. The influences of the experimental parameters including sample pH, eluent volume and eluent type, sample volume, and interference of some ions on the recoveries of the gold ion were investigated. The proposed method was applied for preconcentration and determination of gold in different samples.

  9. Indium determination in different environmental materials by electrothermal atomic absorption spectrometry with Amberlite XAD-2 coated with 1-(2-pyridylazo)-2-naphthol.

    Science.gov (United States)

    Martínez A, N C; Barrera, Adela Bermejo; Bermejo B, P

    2005-04-30

    Methods were developed for indium (In) determination in complex ores by electrothermal atomization atomic absorption spectrometry using matrix modification after its separation with Amberlite XAD-2 coated with 1-(2-pyridylazo)-2-naphthol (PAN). Palladium-magnesium, nickel, and zinc nitrates were used as matrix modifiers and were compared in terms of maximum pyrolysis temperature, sensitivity and background signal. They have enhanced the absorption signals for indium, respectively eliminating the matrix interferences. The standard additions method was applied. The relative standard deviations for six replicate determinations were in the range 0.3-4.0% for indium in different ores samples for indium concentrations 7.6-209mugg(-1). The recommended method was applied to the indium determination in real samples. The data obtained by this method were in good agreement with those obtained by ICP-AES.

  10. Contents of cadmium, mercury and lead in fish from the Atlantic sea (Morocco) determined by atomic absorption spectrometry.

    Science.gov (United States)

    Chahid, Adil; Hilali, Mustapha; Benlhachimi, Abdeljalil; Bouzid, Taoufiq

    2014-03-15

    As a part of a specific monitoring program, lead (Pb) cadmium (Cd) and mercury (Hg) concentrations in important species of fish from various fishing ports of the southern Kingdom of Morocco (Sardina pilchardus, Scomber scombrus, Plectorhinchus mediterraneus, Trachurus trachurus, Octopus vulgaris, Boops boops, Sarda sarda, Trisopterus capelanus, and Conger conger) were investigated by the Moroccan Reference Laboratory (NRL) for trace elements in foodstuffs of animal origin. The samples were analysed for lead and cadmium by a graphite furnace atomic absorption spectrometry (GFAAS); and for mercury by cold vapour atomic absorption spectrometry (CVAAS). The results were expressed as μg/g of wet weight (w/w). The levels of Cd, Pb and Hg in muscles of fish were 0.009-0.036, 0.013-0.114 and 0.049-0.194 μg/g, respectively. The present study showed that different metals were present in the sample at different levels but within the maximum residual levels prescribed by the EU for the fish and shellfish from these areas, in general, should cause no health problems for consumers.

  11. Influence of matrix effects on determination of the trace element content in zirconium by the atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    A.N. Kulik

    2009-01-01

    Full Text Available The influence of sample matrix prepared on the basis of hydrofluoric acid on the measured content of trace elements in zirconium was studied. The accuracy of determination of the trace element content was verified by the “introduced-found” method. Based on verification results the temperature regime of electrothermal atomizer was optimized.

  12. Comparison of different sample preparation methods for platinum determination in cultured cells by graphite furnace atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Man Xiao

    2017-01-01

    Full Text Available Background Platinum-based agents are widely used in chemotherapy against solid tumors and insufficient intracellular drug accumulation is one of the leading causes of platinum resistance which is associated with poor survival of tumor patients. Thus, the detection of intracellular platinum is pivotal for studies aiming to overcome platinum resistance. In the present study, we aimed to establish a reliable graphite furnace atomic absorption spectrometry (GFAAS-based assay to quantify the intracellular platinum content for cultured cells. Methods Several most commonly applied cell preparation methods, including 0.2% HNO3, 0.2% Triton X-100, concentrated nitric acid, RIPA combined with concentrated nitric acid and hydroxide, followed by GFAAS for platinum detection were compared in ovarian, cervical and liver cancer cell lines to obtain the optimal one, and parameters regarding linearity, accuracy, precision and sensitivity were evaluated. Influence of other metals on platinum detection and the storage conditions of samples were also determined. Results The treatment of cells with 0.2% HNO3 was superior to other approaches with fewer platinum loss and better repeatability. The recovery rate and precision of this method were 97.3%–103.0% and 1.4%–3.8%, respectively. The average recoveries in the presence of other metals were 95.1%–103.1%. The detection limit was 13.23 ug/L. The recovery rate of platinum remained acceptable even in cell samples stored in −20 °C or −80 °C for two months. Discussion After comparison, we found that 0.2% HNO3 was optimal for intracellular platinum quantification based on GFAAS, which presented values compatible with that of inductively-coupled plasma mass-spectrometry (ICP-MS, and this is partially attributed to the simplicity of this method. Moreover, the assay was proved to be accurate, sensitive, cost-effective and suitable for the research of platinum-based antitumor therapy.

  13. On the opportunity of spectroscopic determination of absolute atomic densities in non-equilibrium plasmas from measured relative intensities within resonance multiplets distorted by self-absorption

    CERN Document Server

    Lavrov, B P

    2007-01-01

    The opportunities of the application of the recently proposed approach in optical emission spectroscopy of non-equilibrium plasmas have been studied. The approach consists of several methods of the determination of {\\em absolute} particle densities of atoms from measured {\\em relative} intensities within resonance multiplets distorted by self-absorption. All available spectroscopic data concerning resonance spectral lines of atoms having multiplet ground states from boron up to gallium were analyzed. It is found that in the case of C, O, F, S and Cl atoms an application of the methods needs VUV technique, while densities of B, Al, Si, Sc, Ti, V, Co, Ni, Ga atoms may be obtained by means of the intensity measurements in UV and visible parts of emission spectra suitable for ordinary spectrometers used for optical diagnostics and monitoring of non-equilibrium plasmas including industrial plasma technologies.

  14. Preconcentration of Copper Using 1,5-Diphenyl Carbazide as the Complexing Agent via Dispersive Liquid-Liquid Microextraction and Determination by Flame Atomic Absorption Spectrometry

    OpenAIRE

    Reyhaneh Rahnama; Elaheh Shafiei; Mohammad Reza Jamali

    2013-01-01

    We report a simple and sensitive microextraction system for the preconcentration and determination of Cu (II) by flame atomic absorption spectrometry (FAAS). Dispersive liquid-liquid microextraction is a modified solvent extraction method and its acceptor-to-donor phase ratio is greatly reduced compared with other methods. In the proposed approach, 1,5-diphenyl carbazide (DPC) was used as a copper ion selective complexing agent. Several variables such as the extraction and dispersive solvent ...

  15. Determination of Mecruy at Trace Level in Natural Water Samples by Hydride Generation Atomic Absorption Spectrophotometry after Cloud Point Extraction Preconcentration

    Institute of Scientific and Technical Information of China (English)

    Ji Ying SONG; Ming HOU; Li Xiang ZHANG

    2006-01-01

    A method for the determination of trace mercury in water samples by hydride generation atomic absorption spectrophotometry after cloud point extraction was proposed in the present work.The effects of pH, concentration of surfactant, and equilibration time on cloud point extraction were discussed. The enhancement factor of 20 and the detection limit of 0.039 μg/L were obtained for mercury with relative standard deviation of 4.8% (n = 11).

  16. Trace mercury determination in drinking and natural water after preconcentration and separation by DLLME-SFO method coupled with cold vapor atomic absorption spectrometry

    OpenAIRE

    Abdollahi Atousa; Amirkavehei Mooud; Gheisari Mohammad Mehdi; Tadayon Fariba

    2014-01-01

    A novel dispersive liquid–liquid microextraction based on solidification of floating organic drop (DLLME-SFO) for simultaneous separation/preconcentration of ultra trace amounts of mercury was used. A method based on amalgamation was used for collection of gaseous mercury on gold coated sand (Gold trap). The concentration of mercury was determined by cold vapor atomic absorption spectrometry (CV-AAS). The DLLME-SFO behavior of mercury by using dithizone as complexing agent was systematically ...

  17. 原子吸收法测定化探样中的微量汞%Determination of Trace Mercury in Geochemical Samples by Cold Atomic Absorption Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    王茹

    2014-01-01

    化探样品中微量汞的测定多采用原子荧光法,采用冷原子吸收法测汞也有报道。本法用简易吸收装置于 GGX-2型原子吸收光谱仪上,进行化探样品中微量汞的冷原子吸收法测定,测定结果表明,汞的含量在(0.01~2)×10-6范围呈线性,经对省Ⅱ级标样36号、38号进行实验,相对标准偏差分别为10.56%和17.83%,可满足化探要求。%Trace mercury in geochemical samples is normally determined by atomic fluorescence method. There also are reports on determination of trace mercury in geochemical samples by cold atomic absorption spectroscopy. The method is to install simple absorption equipment on GGX-2 atomic absorption spectrometer to determine trace mercury in geochemical samples. The results show that, the content of mercury is linear in the range of (0.01~2)× 10-6. Provincial level Ⅱ sample No. 36 and No. 38 are determined with the cold atomic absorption spectroscopy, relative standard deviations are 10.56% and 17.83% respectively, so the method can meet the requirements of geochemical exploration.

  18. Atomic absorption spectroscopy in ion channel screening.

    Science.gov (United States)

    Stankovich, Larisa; Wicks, David; Despotovski, Sasko; Liang, Dong

    2004-10-01

    This article examines the utility of atomic absorption spectroscopy, in conjunction with cold flux assays, to ion channel screening. The multiplicity of ion channels that can be interrogated using cold flux assays and atomic absorption spectroscopy is summarized. The importance of atomic absorption spectroscopy as a screening tool is further elaborated upon by providing examples of the relevance of ion channels to various physiological processes and targeted diseases.

  19. Determination of gold, indium, tellurium and thallium in the same sample digest of geological materials by atomic-absorption spectroscopy and two-step solvent extraction

    Science.gov (United States)

    Hubert, A.E.; Chao, T.T.

    1985-01-01

    A rock, soil, or stream-sediment sample is decomposed with hydrofluoric acid, aqua regia, and hydrobromic acid-bromine solution. Gold, thallium, indium and tellurium are separated and concentrated from the sample digest by a two-step MIBK extraction at two concentrations of hydrobromic add. Gold and thallium are first extracted from 0.1M hydrobromic acid medium, then indium and tellurium are extracted from 3M hydrobromic acid in the presence of ascorbic acid to eliminate iron interference. The elements are then determined by flame atomic-absorption spectrophotometry. The two-step solvent extraction can also be used in conjunction with electrothermal atomic-absorption methods to lower the detection limits for all four metals in geological materials. ?? 1985.

  20. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of antimony by automated-hydride atomic absorption spectrophotometry

    Science.gov (United States)

    Brown, G.E.; McLain, B.J.

    1994-01-01

    The analysis of natural-water samples for antimony by automated-hydride atomic absorption spectrophotometry is described. Samples are prepared for analysis by addition of potassium and hydrochloric acid followed by an autoclave digestion. After the digestion, potassium iodide and sodium borohydride are added automatically. Antimony hydride (stibine) gas is generated, then swept into a heated quartz cell for determination of antimony by atomic absorption spectrophotometry. Precision and accuracy data are presented. Results obtained on standard reference water samples agree with means established by interlaboratory studies. Spike recoveries for actual samples range from 90 to 114 percent. Replicate analyses of water samples of varying matrices give relative standard deviations from 3 to 10 percent.

  1. Solid Phase Extraction and Determination of Nickel in Water Samples by Using Novel Thiol-Containing Sulfonamide Polymeric Resin and Atomic Absorption Spectrophotometer

    Institute of Scientific and Technical Information of China (English)

    Nagihan M Karaaslan; B Filiz Senkal; Cigdem Er; Halim Avci; Mehmet Yaman

    2011-01-01

    Interest in preconcentration techniques for the determination of metals at ultratrace levels still continues increasingly because of some disadvantages of flameless atomic absorption spectrometry as well as the high costs of other sensitive methods in compared to flame atomic absorption spectrometry.In this study,thiol-containing sulfonamide resin was synthesized,characterized and applied as a new sorption material for solid phase extraction of nickel in drinking water samples.After preconcentration procedure,flame atomic absorption spectrometry was used for determinations.Optimum parameters were found to be pH=3.2,contact time =20 min and eluate volume=3 mL.The limit of detection was found to be 0.75 ng · mL-1.The synthesized resin exhibits the superiority in compared to the other adsorption reagents because of the fact that there is no necessity of any complexing reagent,high sorption capacity as well as the relatively fast extraction rate.The Ni concentrations in the studied 21 kind of water samples were found to be in the range of BDL-4.0 ng ·mL-1.

  2. Absorption imaging of a single atom

    Science.gov (United States)

    Streed, Erik W.; Jechow, Andreas; Norton, Benjamin G.; Kielpinski, David

    2012-07-01

    Absorption imaging has played a key role in the advancement of science from van Leeuwenhoek's discovery of red blood cells to modern observations of dust clouds in stellar nebulas and Bose-Einstein condensates. Here we show the first absorption imaging of a single atom isolated in a vacuum. The optical properties of atoms are thoroughly understood, so a single atom is an ideal system for testing the limits of absorption imaging. A single atomic ion was confined in an RF Paul trap and the absorption imaged at near wavelength resolution with a phase Fresnel lens. The observed image contrast of 3.1 (3)% is the maximum theoretically allowed for the imaging resolution of our set-up. The absorption of photons by single atoms is of immediate interest for quantum information processing. Our results also point out new opportunities in imaging of light-sensitive samples both in the optical and X-ray regimes.

  3. Optimized absorption imaging of mesoscopic atomic clouds

    Science.gov (United States)

    Muessel, Wolfgang; Strobel, Helmut; Joos, Maxime; Nicklas, Eike; Stroescu, Ion; Tomkovič, Jiří; Hume, David B.; Oberthaler, Markus K.

    2013-10-01

    We report on the optimization of high-intensity absorption imaging for small Bose-Einstein condensates. The imaging calibration exploits the linear scaling of the quantum projection noise with the mean number of atoms for a coherent spin state. After optimization for atomic clouds containing up to 300 atoms, we find an atom number resolution of atoms, mainly limited by photon shot noise and radiation pressure.

  4. Various applications of Zeeman atomic absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, H.

    1978-06-01

    The application of the Zeeman effect to atomic absorption spectroscopy has been studied over the past several years. This technique has a larger area of application than conventional AAS because of its high degree of selectivity. The ZAA technique can be used for organometallic species determination by interfacing with a high-pressure liquid chromatograph. Various kinds of eluents can be directly introduced in the ZAA system; even organic solvents or high-concentration salt solutions. For example, the Co atom in the functional center of Vitamin B12 molecule was separately analyzed in the presence of much larger amounts of inorganic Co. In the ZAA technique, interference caused by direct spectral overlap can also be corrected. As a typical example, the Sb line at 217.02 nm overlaps the Pb absorption line at 217.00 nm. However, 1000 ppM of Pb did not cause any interference signal in the Sb analysis by ZAA. This is especially important in the analysis of gun powder residue that is often carried out by chemists working in the forensic field. In the determination of trace elements in matrices of unknown composition, the ZAA technique achieved highly reliable results by employing the standard addition method to correct for chemical interferences, because any nonspecific absorption or emission does not give rise to interference signals with this technique.

  5. A pre-concentration procedure using coprecipitation for determination of lead and iron in several samples using flame atomic absorption spectrometry

    OpenAIRE

    Ferreira, Sergio Luis Costa; Saracoglu, S.; Soylak, Mustafa; Peker, D. S. Kacar; Elci, L.; Santos, W. N. L. dos; Lemos, Valfredo Azevedo

    2006-01-01

    Texto completo: acesso restrito. p.133–137 The present paper proposes a pre-concentration procedure for determination of lead and iron in several samples by flame atomic absorption spectrometry. In it, lead(II) and iron(III) ions are coprecipitated using the violuric acid–copper(II) system as collector. Afterwards, the precipitate is dissolved with 1 M HNO3 solution and the metal ions are determined. The optimization step was performed using factorial design involving the variables: pH, v...

  6. Organic, inorganic and total mercury determination in fish by chemical vapor generation with collection on a gold gauze and electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Duarte, Fábio Andrei; Bizzi, Cezar Augusto; Antes, Fabiane Goldschmidt; Dressler, Valderi Luiz; Flores, Érico Marlon de Moraes

    2009-06-01

    A method for organic, inorganic and total mercury determination in fish tissue has been developed using chemical vapor generation and collection of mercury vapor on a gold gauze inside a graphite tube and further atomization by electrothermal atomic absorption spectrometry. After drying and cryogenic grinding, potassium bromide and hydrochloric acid solution (1 mol L - 1 KBr in 6 mol L - 1 HCl) was added to the samples. After centrifugation, total mercury was determined in the supernatant. Organomercury compounds were selectively extracted from KBr solution using chloroform and the resultant solution was back extracted with 1% m/v L-cysteine. This solution was used for organic Hg determination. Inorganic Hg remaining in KBr solution was directly determined by chemical vapor generation electrothermal atomic absorption spectrometry. Mercury vapor generation from extracts was performed using 1 mol L - 1 HCl and 2.5% m/v NaBH 4 solutions and a batch chemical vapor generation system. Mercury vapor was collected on the gold gauze heated resistively at 80 °C and the atomization temperature was set at 650 °C. The selectivity of extraction was evaluated using liquid chromatography coupled to chemical vapor generation and determination by inductively coupled plasma mass spectrometry. The proposed method was applied for mercury analysis in shark, croaker and tuna fish tissues. Certified reference materials were used to check accuracy and the agreement was better than 95%. The characteristic mass was 60 pg and method limits of detection were 5, 1 and 1 ng g - 1 for organic, inorganic and total mercury, respectively. With the proposed method it was possible to analyze up to 2, 2 and 6 samples per hour for organic, inorganic and total Hg determination, respectively.

  7. Organic, inorganic and total mercury determination in fish by chemical vapor generation with collection on a gold gauze and electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Fabio Andrei; Bizzi, Cezar Augusto; Goldschmidt Antes, Fabiane; Dressler, Valderi Luiz [Departamento de Quimica, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil); Flores, Erico Marlon de Moraes [Departamento de Quimica, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil)], E-mail: flores@quimica.ufsm.br

    2009-06-15

    A method for organic, inorganic and total mercury determination in fish tissue has been developed using chemical vapor generation and collection of mercury vapor on a gold gauze inside a graphite tube and further atomization by electrothermal atomic absorption spectrometry. After drying and cryogenic grinding, potassium bromide and hydrochloric acid solution (1 mol L{sup - 1} KBr in 6 mol L{sup - 1} HCl) was added to the samples. After centrifugation, total mercury was determined in the supernatant. Organomercury compounds were selectively extracted from KBr solution using chloroform and the resultant solution was back extracted with 1% m/v L-cysteine. This solution was used for organic Hg determination. Inorganic Hg remaining in KBr solution was directly determined by chemical vapor generation electrothermal atomic absorption spectrometry. Mercury vapor generation from extracts was performed using 1 mol L{sup - 1} HCl and 2.5% m/v NaBH{sub 4} solutions and a batch chemical vapor generation system. Mercury vapor was collected on the gold gauze heated resistively at 80 deg. C and the atomization temperature was set at 650 deg. C. The selectivity of extraction was evaluated using liquid chromatography coupled to chemical vapor generation and determination by inductively coupled plasma mass spectrometry. The proposed method was applied for mercury analysis in shark, croaker and tuna fish tissues. Certified reference materials were used to check accuracy and the agreement was better than 95%. The characteristic mass was 60 pg and method limits of detection were 5, 1 and 1 ng g{sup - 1} for organic, inorganic and total mercury, respectively. With the proposed method it was possible to analyze up to 2, 2 and 6 samples per hour for organic, inorganic and total Hg determination, respectively.

  8. Comparison of selenium determination in liver samples by atomic absorption spectroscopy and inductively coupled plasma-mass spectrometry.

    Science.gov (United States)

    Miksa, Irina Rudik; Buckley, Carol L; Carpenter, Nancy P; Poppenga, Robert H

    2005-07-01

    Selenium (Se) is an essential trace element that is often deficient in the natural diets of domestic animal species. The measurement of Se in whole blood or liver is the most accurate way to assess Se status for diagnostic purposes. This study was conducted to compare hydride generation atomic absorption spectroscopy (HG-AAS) with inductively coupled plasma-mass spectrometry (ICP-MS) for the detection and quantification of Se in liver samples. Sample digestion was accomplished with magnesium nitrate and nitric acid for HG-AAS and ICP-MS, respectively. The ICP-MS detection was optimized for 82Se with yttrium used as the internal standard and resulted in a method detection limit of 0.12 microg/g. Selenium was quantified by both methods in 310 samples from a variety of species that were submitted to the Toxicology Laboratory at New Bolton Center (Kennett Square, PA) for routine diagnostic testing. Paired measurements for each sample were evaluated by a mean difference plot method. Limits of agreement were used to describe the maximum differences likely to occur between the 2 methods. Results suggest that under the specified conditions ICP-MS can be reliably used in place of AAS for quantitation of tissue Se at or below 2 microg/g to differentiate between adequate and deficient liver Se concentrations.

  9. Standardization and validation of a new atomic absorption spectroscopy technique for determination and quantitation of aluminium adjuvant in immunobiologicals.

    Science.gov (United States)

    Mishra, Arti; Bhalla, Sumir Rai; Rawat, Sameera; Bansal, Vivek; Sehgal, Rakesh; Kumar, Sunil

    2007-10-01

    In the present study, Aluminium quantification in immunobiologicals has been described using atomic absorption spectroscopy (AAS) technique. The assay was found to be linear in 25-125 microg/ml Aluminium range. The procedure was found to be accurate for different vaccines with recoveries of external additions ranging between 93.26 and 103.41%. The mean Limit of Variation (L.V.) for both intra- and inter-assay precision was calculated to be 1.62 and 2.22%, respectively. Further the procedure was found to be robust in relation to digestion temperature, alteration in acid (HNO(3) and H(2)SO(4)) ratio used for sample digestion and storage of digested vaccine samples up to a period of 15 days. After validation, AAS method was compared for its equivalency with routinely used complexometric titration method. On simultaneously applying on seven different groups of both bacterial and viral vaccines, viz., DPT, DT, TT, Hepatitis-A and B, Antirabies vaccine (cell culture) and tetravalent DPT-Hib, a high degree of positive correlation (+0.85-0.998) among AAS and titration methods was observed. Further AAS method was found to have an edge over complexometric titration method that a group of vaccines, viz., ARV (cell culture, adsorbed) and Hepatitis-A, in which Aluminium estimation is not feasible by pharmacopoeial approved complexometric titration method (possibly due to some interference in the sample matrix), this newly described and validated AAS assay procedure delivered accurate and reproducible results.

  10. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of chromium in water by graphite furnace atomic absorption spectrophotometry

    Science.gov (United States)

    McLain, B.J.

    1993-01-01

    Graphite furnace atomic absorption spectrophotometry is a sensitive, precise, and accurate method for the determination of chromium in natural water samples. The detection limit for this analytical method is 0.4 microg/L with a working linear limit of 25.0 microg/L. The precision at the detection limit ranges from 20 to 57 percent relative standard deviation (RSD) with an improvement to 4.6 percent RSD for concentrations more than 3 microg/L. Accuracy of this method was determined for a variety of reference standards that was representative of the analytical range. The results were within the established standard deviations. Samples were spiked with known concentrations of chromium with recoveries ranging from 84 to 122 percent. In addition, a comparison of data between graphite furnace atomic absorption spectrophotometry and direct-current plasma atomic emission spectrometry resulted in suitable agreement between the two methods, with an average deviation of +/- 2.0 microg/L throughout the analytical range.

  11. Comparison of action of mixed permanent chemical modifiers for cadmium and lead determination in sediments and soils by slurry sampling graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Dobrowolski, Ryszard; Adamczyk, Agnieszka; Otto, Magdalena

    2010-09-15

    Slurry sampling atomic absorption spectrometry with electrothermal atomization was used to the determination of cadmium (Cd) and lead (Pb) in soils and sediments using permanent modifiers. Comparison of action of mixed permanent modifiers niobium (Nb)/iridium (Ir) and tungsten (W)/iridium (Ir) were studied in detail. The effect of amount of Ir, W and Nb on analytical signals of Cd and Pb was examined. The optimal amounts of modifiers for Cd and Pb determination were stated. Niobium carbide formation on graphite surface was studied for different pyrolysis temperatures. Finally for Cd determination in sediments and soils 200 microg of Nb mixed with 5 microg of Ir was used as permanent modifiers and 15 microg of Nb mixed with 200 microg of Ir for Pb determination. Suspensions were prepared in 5% HNO(3). The analytical procedure was optimized carefully basing on data from pyrolysis and atomization curves studies. Ammonium dihydrogen phosphate was used additionally as matrix modifier during Cd determination in samples in order to prevent interferences coming from matrix components. The analysis of CRMs confirmed the reliability of the proposed approach. The precision and accuracy of Cd and Pb determination by the described method for soils and sediments were acceptable.

  12. Determination of lead and cadmium in ceramicware leach solutions by graphite furnace atomic absorption spectroscopy: method development and interlaboratory trial.

    Science.gov (United States)

    Hight, S C

    2001-01-01

    This method was developed to improve sensitivity and eliminate time consuming, evaporative pre-concentration in AOAC Method 973.82 and American Society for Testing and Materials method C738 for testing foodware. The method was developed using leach solutions obtained by leaching 9 differently decorated ceramic vessels with 4% acetic acid for 24 h at room temperature. Lead and cadmium concentrations in leach solutions were 0.005-17,600 and 0.0004-0.500 microg/mL, respectively. Concentrations were determined using peak area, phosphate chemical modifier (8.3 microg PO4(-3)), and a standard curve for quantitation. Optimized pre-atomization and atomization temperatures were 1,300 and 1,800 degrees C, respectively, for Pb and 1,100 and 1,700 degrees C, respectively, for Cd. Characteristic masses (mo) were 10 and 0.4 pg for Pb and Cd, respectively. Precision of repeated analyses of calibration solutions was < or =3% relative standard deviation. Precision of duplicate leach solution analyses on different days was 0-9% relative difference. Recovery from fortified leach solutions was 96-106%. Results obtained by this method agreed 92-110% with those of confirmatory analyses. Results of certified reference material solutions agreed 94-100% with certificate values. Pb and Cd limits of quantitation (LOQ) were 0.005 and 0.0005 microg/mL, respectively. Results from 3 trial laboratories for 4 leach solutions containing Pb and Cd concentrations of 0.017-1.47 and <0.0005-0.0864 microg/mL, respectively, agreed 89-102% with results of the author. Two attributes of this method were noteworthy: (1) Background absorbance due to organic matter was entirely absent from atomization profiles, making the use of short pre-atomization hold times (2 s) possible. (2) Instrument precision was excellent and only one determination per solution was needed. Acceptance criteria for quality control measurements and a practical procedure for estimating the method LOQ during routine regulatory analyses

  13. Preconcentration of Co, Ni, Cd and Zn on naphthalene–2,4,6-trimorpholino-1,3,5-triazin adsorbent and flame atomic absorption determination

    Directory of Open Access Journals (Sweden)

    TAYYEBEH MADRAKIAN

    2010-05-01

    Full Text Available A preconcentration method was developed for the determination of trace amounts of Co, Ni, Cd and Zn by atomic absorption spectrometry. The method is based on the retention of the metal cations by naphthalene–2,4,6-trimorpholino-1,3,5-triazin adsorbent in a column. The adsorbed metals were then eluted from the column with hydrochloric acid and the Co, Ni, Cd and Zn were determined by flame atomic absorption spectrometry. The optimal extraction and elution conditions were studied. The effects of diverse ions on the preconcentration were also investigated. A preconcentration factor of 250 for Co(II, Ni(II and Zn(II, and 400 for Cd(II can easily be achieved. Calibration graphs were obtained and the detection limits of the method for Co(II, Ni(II, Cd(II and Zn(II were 0.51, 0.49, 0.17 and 0.10 ng mL-1, respectively. The relative standard deviations (RSD of 0.37–2.31 % for Co, 0.37–3.73 % for Ni, 2.20–2.40 % for Cd and 1.50–2.56 % for Zn were obtained. The method was also used for the simultaneous preconcentration of these elements and the method was successfully applied to their preconcentration and determination. The method was applied to the determination of Co, Ni, Cd and Zn in several real samples.

  14. Accuracy of a method based on atomic absorption spectrometry to determine inorganic arsenic in food: Outcome of the collaborative trial IMEP-41

    DEFF Research Database (Denmark)

    Fiamegkos, I.; Cordeiro, F.; Robouch, P.;

    2016-01-01

    the release of all arsenic species into solution, and (ii) subsequent extraction of the inorganic arsenic present in the acid medium using chloroform followed by back-extraction to acidic medium. The final detection and quantification is done by flow injection hydride generation atomic absorption spectrometry......A collaborative trial was conducted to determine the performance characteristics of an analytical method for the quantification of inorganic arsenic (iAs) in food. The method is based on (i) solubilisation of the protein matrix with concentrated hydrochloric acid to denature proteins and allow...

  15. Determination of trace amounts of molybdenum in plant tissue by solvent extraction-atomic-absorption and direct-current plasma emission spectrometry.

    Science.gov (United States)

    Lajunen, L H; Kubin, A

    1986-03-01

    Methods are presented for determination of molybdenum in plant tissue by flame and graphite-furnace atomic-absorption spectrometry and direct-current argon-plasma emission spectrometry. The samples are digested in HNO(3)-H(2)SO(4)-HC1O(4) mixture, and Mo is separated and concentrated by chelation and extraction. Three organic solvents (methyl isobutyl ketone, di-isobutyl ketone and isoamyl alcohol) and two ligands (8-hydroxyquinoline and toluene-3,4-dithiol) were studied. The procedure were tested on pine needle and birch leaf samples.

  16. Determination of traces of Mo in soils and geological materials by solvent extraction of the molybdenum-thiocyanate complex and atomic absorption.

    Science.gov (United States)

    Kim, C H; Owens, C M; Smythe, L E

    1974-06-01

    Comprehensive studies of the extraction of the molybdenum-thiocyanate complex with methyl isobutyl ketone have resulted in an improved method for the determination of traces of molybdenum in soils and geological materials by atomic-absorption spectroscopy. The method is applicable in the range 1-500 ppm Mo, with 1-g samples, giving relative standard deviations not exceeding about 8% at a level of 1 ppm. The limit of detection is 0.1 ppm. There are few interferences, and large quantities of iron are without effect.

  17. Cloud Point Extraction and Flame Atomic Absorption Spectrometric Determination of Lead, Cadmium and Palladium in Some Food and Biological Samples

    Directory of Open Access Journals (Sweden)

    M. Soylak

    2011-12-01

    Full Text Available The proposed method is based on the complexation of the Pb2+, Cd2+ and Pd2+ ions with 3-(1-(1-H-Indol-3-Yl-3-phenylallyl-1H-indole (IPAI at pH 8.0 in the presence of Triton X-114. The phase separation occured when micellar solution was heated at 55 ◦C. The surfactant-rich phase, diluted to 0.5 mL via 1.0 mol L−1 nitric acid in methanol was directly introduced into the nebulizer of the flame atomic absorption spectrometry (FAAS. Influence of variables such as pH, amount of ligand and Triton X-114, heating time and temperature were evaluated and optimized. The optimized enhancement factors for Pb2+, Cd2+ and Pd2+ ions were 22, 33 and 23, respectively and the detection limit (DLs was between of 1.6–2.6 µgL−1. The relative standard deviation (RSD of each ion was found to be less than 4.6% at 100 µgL−1. In addition, the calibration graphs were linear in the range of 0.01-0.22 μg mL−1 for Cd2+ ion, 0.018-0.26 μg mL−1 for Pb2+ ion and 0.02-0.27 μg mL−1 for Pd2+ ion with the correlation coefficients in the range of 0.995–0.999.

  18. Determination of some heavy metal levels in soft drinks on the Ghanaian market using atomic absorption spectrometry method.

    Science.gov (United States)

    Ackah, Michael; Anim, Alfred Kwablah; Zakaria, Nafisatu; Osei, Juliet; Saah-Nyarko, Esther; Gyamfi, Eva Tabuaa; Tulasi, Delali; Enti-Brown, Sheriff; Hanson, John; Bentil, Nash Owusu

    2014-12-01

    Twenty-three soft drink samples (i.e., four pineapple-based fruit drinks, eight citrus-based fruit juices, one soya-based drink, three cola carbonated drinks, one apple-based fruit drink, and six cocktail fruit drinks) were randomly purchased from retail outlets in an urban market in Accra and analyzed for the concentrations of iron, cobalt, cadmium, zinc, lead, and copper using flame atomic absorption spectrometry. The mean concentration of iron and cadmium were 0.723 ± 0.448 mg/L and 0.032 ± 0.012 mg/L, respectively. The mean cobalt concentration was 0.071 ± 0.049 mg/L, while the mean Zn concentration in the samples was 0.060 ± 0.097 mg/L. The mean concentrations of Pb and Cu in the fruit juice samples were 0.178 ± 0.091 mg/L and 0.053 ± 0.063 mg/L respectively. About 78 % of the samples exceeded the United States Environmental Protection Agency (USEPA) maximum contaminant level of 0.3 mg/L prescribed for iron, whereas all the samples exceeded the USEPA maximum contaminant level of 0.005 mg/L prescribed for cadmium. About 91 % of the samples exceeded the EU maximum contaminant level prescribed for lead insoft drinks.

  19. Minimizing chemical interference errors for the determination of lithium in brines by flame atomic absorption spectroscopy analysis

    Institute of Scientific and Technical Information of China (English)

    WEN Xianming; MA Peihua; ZHU Geqin; WU Zhiming

    2006-01-01

    Chemical interferences (ionization and oxide/hydroxide formation) on the atomic absorbance signal of lithium in FAAS analysis of brine samples are elaborated in this article. It is suggested that inadequate or overaddition of deionization buffers can lead to loss of sensitivities under particular operating conditions. In the analysis of brine samples, signal enhancing and oxide/hydroxide formation inducing signal reduction resulting from overaddition of deionization buffers can be seen with varying amounts of chemical buffers. Based on experimental results, the authors have arrived at the op timized operating conditions for the detection of lithium, under which both ionization and stable compound formation can be suppressed. This is a simplified and quick method with adequate accuracy and precision for the determination of lithium in routine brine samples from chemical plants or R&D laboratories, which contain comparable amounts of lithium with some other components.

  20. Graphite furnace and hydride generation atomic absorption spectrometric determination of cadmium, lead, and tin traces in natural surface waters: study of preconcentration technique performance.

    Science.gov (United States)

    Tsogas, George Z; Giokas, Dimosthenis L; Vlessidis, Athanasios G

    2009-04-30

    In this study three major types of preconcentration methods based upon different principles (cation exchange, physical absorption and hydrophobic extraction) were evaluated and optimized for the extraction and determination of three highly toxic heavy metals namely Cd, Pb and Sn by graphite furnace and hybrid generation atomic absorption spectrometry in real samples. The optimum analytical conditions were examined and the analytical features of each method were revealed and compared. Detection limits as low as 0.003-0.025 microg L(-1) for Cd(2+), 0.05-0.10 microg L(-1) for Pb(2+) and 0.1-0.25 microg L(-1) for Sn(4+) depending on the extraction method were obtained with RSD values between 3.08% and 6.11%. A preliminary assessment of the pollution status of three important natural ecosystems in Epirus region (NW Greece) was performed and some early conclusions were drawn and discussed.

  1. Ionic liquid ultrasound assisted dispersive liquid-liquid microextraction method for preconcentration of trace amounts of rhodium prior to flame atomic absorption spectrometry determination

    Energy Technology Data Exchange (ETDEWEB)

    Molaakbari, Elaheh [Chemistry Department, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Young Research Society, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Mostafavi, Ali, E-mail: mostafavi.ali@gmail.com [Chemistry Department, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Afzali, Daryoush [Environment and Nanochemistry Department, Research Institute of Environmental Science, International Center for Science, High Technology and Environmental Science, Kerman (Iran, Islamic Republic of); Mineral Industries Research Center, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of)

    2011-01-30

    In this article, we consider ionic liquid based ultrasound-assisted dispersive liquid-liquid microextraction of trace amounts of rhodium from aqueous samples and show that this is a fast and reliable sample pre-treatment for the determination of rhodium ions by flame atomic absorption spectrometry. The Rh(III) was transferred into its complex with 2-(5-bromo-2-pyridylazo)-5-diethylamino phenol as a chelating agent, and an ultrasonic bath with the ionic liquid, 1-octyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide at room temperature was used to extract the analyte. The centrifuged rhodium complex was then enriched in the form of ionic liquid droplets and prior to its analysis by flame atomic absorption spectrometry, 300 {mu}L ethanol was added to the ionic liquid-rich phase. Finally, the influence of various parameters on the recovery of Rh(III) was optimized. Under optimum conditions, the calibration graph was linear in the range of 4.0-500.0 ng mL{sup -1}, the detection limit was 0.37 ng mL{sup -1} (3S{sub b}/m, n = 7) and the relative standard deviation was {+-}1.63% (n = 7, C = 200 ng mL{sup -1}). The results show that ionic liquid based ultrasound assisted dispersive liquid-liquid microextraction, combined with flame atomic absorption spectrometry, is a rapid, simple, sensitive and efficient analytical method for the separation and determination of trace amounts of Rh(III) ions with minimum organic solvent consumption.

  2. Determination of ultra trace amounts of bismuth in biological and water samples by electrothermal atomic absorption spectrometry (ET-AAS) after cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Shemirani, Farzaneh; Baghdadi, Majid; Ramezani, Majid; Jamali, Mohammad Reza

    2005-04-04

    A new approach for a cloud point extraction electrothermal atomic absorption spectrometric method was used for determining bismuth. The aqueous analyte was acidified with sulfuric acid (pH 3.0-3.5). Triton X-114 was added as a surfactant and dithizone was used as a complexing agent. After phase separation at 50 deg. C based on the cloud point separation of the mixture, the surfactant-rich phase was diluted using tetrahydrofuran (THF). Twenty microliters of the enriched solution and 10 {mu}l of 0.1% (w/v) Pd(NO{sub 3}){sub 2} as chemical modifier were dispersed into the graphite tube and the analyte determined by electrothermal atomic absorption spectrometry. After optimizing extraction conditions and instrumental parameters, a preconcentration factor of 196 was obtained for a sample of only 10 ml. The detection limit was 0.02 ng ml{sup -1} and the analytical curve was linear for the concentration range of 0.04-0.60 ng ml{sup -1}. Relative standard deviations were <5%. The method was successfully applied for the extraction and determination of bismuth in tap water and biological samples (urine and hair)

  3. Direct atomic absorption determination of cadmium and lead in strongly interfering matrices by double vaporization with a two-step electrothermal atomizer

    Science.gov (United States)

    Grinshtein, Ilia L.; Vilpan, Yuri A.; Saraev, Alexei V.; Vasilieva, Lubov A.

    2001-03-01

    Thermal pretreatment of a sample using double vaporization in a two-step atomizer with a purged vaporizer makes possible the direct analysis of samples with strongly interfering matrices including solids. A porous-graphite capsule or a filter inserted into the vaporizer is used for solid sample analysis. The technique was used for the direct determination of Cd and Pb in human urine, potatoes, wheat, bovine liver, milk powder, grass-cereal mixtures, caprolactam, bituminous-shale and polyvinyl chloride plastic without chemical modification or any other sample pretreatment.

  4. Determination of cobalt in biological samples by electrothermal atomic absorption spectrometry after extraction with 1,5-bis (di-2-pyridylmethylene) thiocarbohydrazide

    Energy Technology Data Exchange (ETDEWEB)

    Collado, G.; Bosch Ojeda, C.; Garcia de Torres, A.; Cano Pavon, J.M. [University of Malaga (Spain)

    1995-06-01

    A method for the determination of trace amounts of cobalt in biological samples by atomic absorption spectrometry with graphite furnace atomization extraction conditions were evaluated from a critical study of the effects of pH, concentration of extractant, shaking time and ionic strength. The detection limit for cobalt is 0.06 ng ml{sup -1} and the calibration is linear from 0.1 to 2.5 ng ml{sup -1}. The relative standard deviation for ten replicate measurements is 1.7 % for 0.5 ng ml{sup -1} of cobalt. The effect of interferences was studied and no interferences from the elements commonly found in biological materials were observed. The chief advantage of the method lies in its maximum allowable aqueous-to-organic phase volume ratio of 30:1. Results from the analysis of some certified biological reference materials are given. (authors). 14 refs., 1 figs., 3 tabs.

  5. Direct solid-sampling electrothermal atomic absorption spectrometry methods for the determination of silicon in oxides of niobium, titanium and zirconium

    Science.gov (United States)

    Dong, Huang Mao; Krivan, Viliam

    2001-09-01

    An electrothermal atomic absorption spectrometer with a transversely heated graphite tube and a solid sampling system based on the boat technique was used for the development of methods for direct determination of silicon in powdered niobium pentoxide, titanium dioxide and zirconium dioxide. In the analysis of niobium pentoxide, serious matrix-caused non-spectral interferences and background were avoided by conversion of the niobium pentoxide matrix into the thermally stable niobium carbide using a methane atmosphere during the pyrolysis stage. For all three materials, calibration procedures using aqueous standard solutions were developed. For titanium dioxide and zirconium dioxide, the accuracy was checked by comparison of the results with those of independent methods, whereby good agreement was achieved. Owing to the high applicable sample amount per atomization (3-15 mg) and almost complete freedom of interference from the blank, limits of detection at the 10-ng g -1 level were achieved.

  6. Evaluation of solid sampling for determination of Mo, Ni, Co, and V in soil by high-resolution continuum source graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Babos, Diego Victor; Barros, Ariane Isis; Ferreira, Edilene Cristina; Neto, José Anchieta Gomes

    2017-04-01

    New methods are proposed for the determination of Mo, Ni, Co, and V in soils using high-resolution continuum source graphite furnace atomic absorption spectrometry with direct solid sampling. Cobalt and V were simultaneously determined, and different analytical lines of Ni and V were monitored to adjust sensitivity for each sample. Accuracy was checked by means of soil certified reference materials, and also by flame atomic absorption spectrometry as comparative technique. The results for Mo, Ni, Co, and V found by proposed methods were in agreement with certified values and with those obtained by the comparative technique at 95% confidence level. The concentrations found in different soil samples were in the ranges 0.19-1.84 mg kg- 1 (Mo), 9.2-22.7 mg kg- 1 (Ni), 1.1-10.7 mg kg- 1 (Co), and 35.6-426.1 mg kg- 1 (V). The relative standard deviations were in the ranges 3.2-10% (Mo), 2.8-9.8% (Ni), 4.0-9.2% (Co), and 1.2-8.0% (V). The limits of quantification for Mo, Ni, Co, and V were 0.027, 0.071, 0.15, and 1.43 ng, respectively.

  7. Preconcentration and determination of ultra-traces of platinum in human serum using the combined electrodeposition-electrothermal atomic absorption spectroscopy (ED-ETAAS) and chemometric method.

    Science.gov (United States)

    Najafi, Nahid Mashkouri; Shahparvizi, Shahram; Rafati, Hasan; Ghasemi, Ensieh; Alizadeh, Reza

    2010-09-21

    Platinum compounds, including cis-dichlorodiaminoplatinum(II) or cisplatin, are an important class of anti-cancer drugs, which should be carefully monitored in the biological fluids. In this study, electrodeposition coupled with electrothermal atomic absorption spectrometry (ETAAS) was used for determination of Pt concentration in the human serum samples. The chemometric techniques were also used to verify the probable interactions among the important and effective parameters in the atomization process. Using response surfaces obtained by two factorial design techniques, the experimental design was applied for three effective parameters namely ashing temperature, atomizing temperature and modifier concentration as effective parameters on the atomization of Pt. The in situ digestions of serum samples, as well as the separation of the ultra-traces of Pt from concomitant in these samples were performed by using the in situ electrodeposition (ED) technique prior to the measurement by ETAAS. Six plasma samples of a patient who was administered parenteral cisplatin were analyzed using the proposed ED-ETAAS technique. The results showed the pharmacokinetic parameters of cisplatin in serum in accordance to the well-established data. A relatively good reproducibility %RSD=2.44, low limit of detection LOD=2.54 microg/L and promising characteristic mass m(o)=91.30 pg were obtained using this technique.

  8. Combination of cloud point extraction and flame atomic absorption spectrometry for preconcentration and determination of nickel and manganese ions in water and food samples

    Energy Technology Data Exchange (ETDEWEB)

    Arpa Sahin, Cigdem, E-mail: carpa@hacettepe.edu.tr [Hacettepe University, Chemistry Department, 06800, Beytepe, Ankara (Turkey); Efecinar, Melis; Satiroglu, Nuray [Hacettepe University, Chemistry Department, 06800, Beytepe, Ankara (Turkey)

    2010-04-15

    A simple, rapid, inexpensive, and nonpolluting cloud point extraction (CPE) technique has been improved for the preconcentration and determination of nickel and manganese. After complexation with p-nitrophenylazoresorcinol (Magneson I), the analytes could be competitively extracted in a surfactant octylphenoxy polyethoxyethanol (Triton X-114), prior to determination by flame atomic absorption spectrometry (FAAS). The effects of experimental conditions such as pH, concentration of chelating agent and surfactant, equilibration temperature and time on CPE were studied. Under the optimum conditions, preconcentration of a 25 mL sample solution permitted the detection of 2.7 ng mL{sup -1} Ni{sup 2+} and 2.9 ng mL{sup -1} Mn{sup 2+} with enrichment factors of 17 and 19 for Ni{sup 2+} and Mn{sup 2+}, respectively. The developed method was applied to the determination of trace nickel and manganese in water and food samples with satisfactory results.

  9. Dispersive liquid-liquid microextraction (DLLME combined with graphite furnace atomic absorption spectrometry (GFAAS for determination of trace Cu and Zn in water Samples

    Directory of Open Access Journals (Sweden)

    Ghorbani A.

    2014-07-01

    Full Text Available Dispersive liquid-liquid microextraction (DLLME combined with graphite furnace atomic absorption spectrometry (GFAAS was proposed for the determination of trace amounts of Copper and Zinc ions using 8-hydroxyquinoline (8-HQ as chelating agent. Several factors influencing the microextraction efficiency of Cu and Zn and their subsequent determinations, such as pH, extraction and disperser solvent type and their volume, concentration of the chelating agent and extraction time were studied, and the optimized experimental conditions were established. After extraction, the enrichment factors were 25 and 26 for Cu and Zn, respectively. The detection limits of the method were 0.025 and 0.0033 μg/L for Cu and Zn, and the relative standard deviations (R.S.D for five determinations of 1 ng/ml Cu and Zn were 8.51% and 7.41%, respectively.

  10. Simultaneous determination of arsenic, cadmium, copper, chromium, nickel, lead and thallium in total digested sediment samples and available fractions by electrothermal atomization atomic absorption spectroscopy (ET AAS).

    Science.gov (United States)

    Álvarez, María Á; Carrillo, Génesis

    2012-08-15

    This study describes the optimization and validation of a quick and simple method for the simultaneous determination of total content and available fractions of As, Cr, Cu, Ni, Pb and Tl in sediments by ET AAS, which has been proved to be useful for environmental research. The optimization was carried out using a 3(3) Box-Behnken factorial design which was applied to matrices of total digestion and to stages 1 and 2 of the modified BCR sequential extraction scheme for sediments in order to determine the appropriate atomization temperatures and masses for the chemical modifiers: Pd(NO(3))(2) and Mg(NO(3))(2). The simultaneous determination of the elements in all matrices considered was performed, without the use of chemical modifiers at atomization temperatures of 1700 °C for Cd and Tl, and 2100 °C for As, Cu, Cr, Ni and Pb, using a standard calibration curve for calibration purposes. The characteristic masses and limits of detection obtained were 36.5, 1.8, 6.5, 28, 34, 46.5 and 48 ρg and 0.11, 0.001, 0.022, 0.04, 0.2, 0.03 and 0.003 μg g(-1) for As, Cd, Cr, Cu, Ni, Pb and Tl, respectively. The analytical procedure was validated by analyzing three sediment certified reference materials (CRM NCS DC 73315 and LKSD-4 for total content and BCR 701 for available fractions). Good accuracy was obtained (tested statistically, P=0.05, and shown by the high recovery for each element in each matrix), except for total As in the matrix of total digestion, where losses of the analyte could be attributed to sample treatment with HNO(3). The precision of the procedure was between 0.6% and 6%.

  11. Continuous Determination of Heavy Metals in Water by Atomic Fluorescence and Atomic Absorption Spectrometry%原子荧光和原子吸收法连续测定水中的重金属

    Institute of Scientific and Technical Information of China (English)

    谢倩

    2015-01-01

    通过剖析原子荧光和原子吸收法的不同消解体系,优化实验条件,确定了原子荧光和原子吸收法连续测定水中的硒、砷、锌、铜的含量的最佳消解条件和最佳仪器测定条件。经加标回收以及标样分析,连续测定的灵敏度高,回收率在95.9%~109%之间,相对标准误差低于4.41%,操作简便快速,结果精确。%By analyzing the different digestion system of atomic fluorescence and atomic absorption method and optimizing experimental conditions, the optimal digestion conditions and the best measurement conditions of instruments for continuous determination selenium, arsenic, zinc, copper content in water by atomic fluorescence and atomic absorption spectrometry were determined.Spiking recovery and standard analysis result showed that continuous measurement had high sensitivity, and the recoveries was between 95.9% and 109%, relative standard deviation was less than 4.41%, the operation was simple, rapid and accurate.

  12. Multielement determination of cadmium and lead in urine by simultaneous electrothermal atomic absorption spectrometry with an end-capped graphite tube.

    Science.gov (United States)

    Correia, Paulo R M; Nomura, Cassiana S; Oliveira, Pedro V

    2003-11-01

    A method for the multielement determination of cadmium and lead in urine is proposed by simultaneous electrothermal atomic absorption spectrometry (SIMAAS) with an end-capped transversely heated graphite atomizer (EC-THGA). The best conditions for cadmium and lead determination were obtained in the presence of NH4H2PO4 as a chemical modifier, using 500 degrees C and 1800 degrees C as the pyrolysis and atomization temperatures, respectively. Urine samples were diluted 1 + 4 directly in autosampler cups with a mixture of 0.125% (w/v) Triton X-100 + 2.5% (v/v) HNO3 + 0.31% (w/v) NH4H2PO4. The optimized heating program was carried out in 57 s, and the instrument calibration was done with aqueous reference solutions. The use of EC-THGA increased the sensitivity of cadmium and lead by 14% and 25%, respectively. The detection limits (n = 20, 3delta) were 0.03 microg L(-1) (0.36 pg) for cadmium and 0.57 microg L(-1) (6.8 pg) for lead. The performance of EC-THGA was acceptable up to 500 heating cycles. The reliability of the entire procedure was checked with the analysis of a lyophilized urine certified reference material. The found concentrations were in agreement with the recommended values (95% confidence level).

  13. Determination of trace amount of cadmium using dispersive liquid-liquid microextraction-slotted quartz tube-flame atomic absorption spectrometry

    Science.gov (United States)

    Fırat, Merve; Bakırdere, Sezgin; Fındıkoğlu, Maral Selin; Kafa, Emine Betül; Yazıcı, Elif; Yolcu, Melda; Büyükpınar, Çağdaş; Chormey, Dotse Selali; Sel, Sabriye; Turak, Fatma

    2017-03-01

    This study was performed to develop a sensitive analytical method for the determination of cadmium by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS) after dispersive liquid-liquid microextraction (DLLME). The parameters affecting the cadmium complex formation and its extraction output were optimized to obtain high extraction efficiency. These included the pH and amount of the buffer solution, and the concentration of the ligand. The DLLME method was comprehensively optimized based on the type and amount of extraction solvent, dispersive solvent and salt. The type and period of mixing needed for a more effective extraction was also investigated. In order to further improve the sensitivity for the determination of cadmium, the flame atomic absorption spectrometry was fitted with a slotted quartz tube to increase the residence time of cadmium atoms in the pathway of incident light from a hollow cathode lamp. The limits of detection and quantitation (LOD and LOQ) for the FAAS were found to be 42 and 140 μg L- 1, respectively. Under the optimum conditions, LOD and LOQ of the FAAS after DLLME were calculated as 1.3 and 4.4 μg L- 1, respectively. Combining both optimized parameters of the DLLME and SQT-FAAS gave 0.5 and 1.5 μg L- 1 as LOD and LOQ, respectively. Accuracy of the method was also checked using a wastewater certified reference material (EU-L-2), and the result was in good agreement with the certified value.

  14. A chemometric approach to the comparison of different sample treatments for metals determination by atomic absorption spectroscopy in aceto Balsamico tradizionale di Modena.

    Science.gov (United States)

    Cocchi, Marina; Franchini, Giancarlo; Manzini, Daniela; Manfredini, Matteo; Marchetti, Andrea; Ulrici, Alessandro

    2004-06-30

    A comparison of different digestion procedures has been carried out for the analysis of metal concentration in samples of vinegars and Aceto Balsamico Tradizionale of Modena (ABTM) coming from an unique barrel set. In particular, classical wet, dry ashing, and closed vessel microwave digestion procedure have been utilized and compared for each investigated species. In a few cases, direct metal determination on ABTM (without treatment procedure) is proposed as possible alternative to sample manipulation. Flame atomic absorption spectrometry was used for the quantification of iron and zinc, while graphite furnace atomic absorption spectrometry was used for all the other elements (i.e., chromium, manganese, cobalt, nickel, copper, cadmium, and lead). The comparison among the different sample treatments was carried out by the use of statistical and chemometric tools. In particular, principal component analysis and ANOVA approaches were used to discriminate between the diverse analytical methods. Furthermore, for all the dissolving techniques, the analytical metal recovery was always evaluated by the application of the recovery function on the same sample matrix. In general, the recoveries were fairly good, ranging from 90 to 103%, except for Cd and Pb with dry ashing, which showed recovery values close to 55% and 67%, respectively. As regards the metals concentration of the investigated samples, the experimental data reveal for some species the presence of concentration slightly over the legal limit fixed for wine and wine vinegar.

  15. Spectral aspects of the determination of Si in organic and aqueous solutions using high-resolution continuum source or line source flame atomic absorption spectrometry

    Science.gov (United States)

    Kowalewska, Zofia; Pilarczyk, Janusz; Gościniak, Łukasz

    2016-06-01

    High-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS) was applied to reveal and investigate spectral interference in the determination of Si. An intensive structured background was observed in the analysis of both aqueous and xylene solutions containing S compounds. This background was attributed to absorption by the CS molecule formed in the N2O-C2H2 flame. The lines of the CS spectrum at least partially overlap all five of the most sensitive Si lines investigated. The 251.611 nm Si line was demonstrated to be the most advantageous. The intensity of the structured background caused by the CS molecule significantly depends on the chemical form of S in the solution and is the highest for the most-volatile CS2. The presence of O atoms in an initial S molecule can diminish the formation of CS. To overcome this S effect, various modes of baseline fitting and background correction were evaluated, including iterative background correction (IBC) and utilization of correction pixels (WRC). These modes were used either independently or in conjunction with least squares background correction (LSBC). The IBC + LSBC mode can correct the extremely strong interference caused by CS2 at an S concentration of 5% w:w in the investigated solution. However, the efficiency of this mode depends on the similarity of the processed spectra and the correction spectra in terms of intensity and in additional effects, such as a sloping baseline. In the vicinity of the Si line, three lines of V were recorded. These lines are well-separated in the HR-CS FAAS spectrum, but they could be a potential source of overcorrection when using line source flame atomic absorption spectrometry (LS FAAS). The expected signal for the 251.625 nm Fe line was not registered at 200 mg L- 1 Fe concentration in the solution, probably due to the diminished population of Fe atoms in the high-temperature flame used. The observations made using HR-CS FAAS helped to establish a "safe" level

  16. Optimization of microwave assisted digestion procedure for the determination of zinc, copper and nickel in tea samples employing flame atomic absorption spectrometry.

    Science.gov (United States)

    Soylak, Mustafa; Tuzen, Mustafa; Souza, Anderson Santos; das Graças Andrade Korn, Maria; Ferreira, Sérgio Luis Costa

    2007-10-22

    The present paper describes the development of a microwave assisted digestion procedure for the determination of zinc, copper and nickel in tea samples employing flame atomic absorption spectrometry (FAAS). The optimization step was performed using a full factorial design (2(3)) involving the factors: composition of the acid mixture (CMA), microwave power (MP) and radiation time (RT). The experiments of this factorial were carried out using a certified reference material of tea GBW 07605 furnished by National Research Centre for Certified Reference Materials, China, being the metal recoveries considered as response. The relative standard deviations of the method were found below 8% for the three elements. The procedure proposed was used for the determination of copper, zinc and nickel in several samples of tea from Turkey. For 10 tea samples analyzed, the concentration achieved for copper, zinc and nickel varied at 6.4-13.1, 7.0-16.5 and 3.1-5.7 (microg g(-1)), respectively.

  17. Determination of Iron in Layered Crystal Sodium Disilicate and Sodium Silicate by Flame Atomic Absorption Spectrometry with Boric Acid as a Matrix Modifier

    Institute of Scientific and Technical Information of China (English)

    Zhi Hua WANG; Min CAI; Shu Jun WANG

    2006-01-01

    The effects of matrix silicate and experimental conditions on the determination of iron in flame atomic absorption spectrometry (FAAS) were investigated. It was found that boric acid as a matrix modifier obviously eliminated silicate interference. Under the optimum operating conditions, the determination results of iron in layered crystal sodium disilicate and sodium silicate samples by FAAS were satisfactory. The linear range of calibration curve is 0-10.5 μg.mL-1, the relative standard deviation of method is 1.2%-2.2%, the recovery of added iron is 96.0%-101%, the of iron of the standard curve method, standard addition calibration and colorimetry method was the same, but the first has the merits of rapid sample preparation, reduced contamination risks and fast analysis.

  18. Flame atomic absorption spectrometric determination of trace quantities of cadmium in water samples after cloud point extraction in Triton X-114 without added chelating agents

    Energy Technology Data Exchange (ETDEWEB)

    Afkhami, Abbas [Department of Chemistry, Faculty of Science, Bu-Ali Sina University, Hamadan (Iran, Islamic Republic of)]. E-mail: afkhami@basu.ac.ir; Madrakian, Tayyebeh [Department of Chemistry, Faculty of Science, Bu-Ali Sina University, Hamadan (Iran, Islamic Republic of); Siampour, Hajar [Department of Chemistry, Faculty of Science, Bu-Ali Sina University, Hamadan (Iran, Islamic Republic of)

    2006-11-16

    A new micell-mediated phase separation method for preconcentration of ultra-trace quantities of cadmium as a prior step to its determination by flame atomic absorption spectrometry has been developed. The method is based on the cloud point extraction (CPE) of cadmium in iodide media with Triton X-114 in the absence of any chelating agent. The optimal extraction and reaction conditions (e.g., acid concentration, iodide concentration, effect of time) were studied, and the analytical characteristics of the method (e.g., limit of detection, linear range, preconcentration, and improvement factors) were obtained. Linearity was obeyed in the range of 3-300 ng mL{sup -1} of cadmium. The detection limit of the method is 1.0 ng mL{sup -1} of cadmium. The interference effect of some anions and cations was also tested. The method was applied to the determination of cadmium in tap water, waste water, and sea water samples.

  19. Application of cloud point preconcentration and flame atomic absorption spectrometry for the determination of cadmium and zinc ions in urine, blood serum and water samples

    Directory of Open Access Journals (Sweden)

    Ardeshir Shokrollahi

    2013-01-01

    Full Text Available A simple, sensitive and selective cloud point extraction procedure is described for the preconcentration and atomic absorption spectrometric determination of Zn2+ and Cd2+ ions in water and biological samples, after complexation with 3,3',3",3'"-tetraindolyl (terephthaloyl dimethane (TTDM in basic medium, using Triton X-114 as nonionic surfactant. Detection limits of 3.0 and 2.0 µg L-1 and quantification limits 10.0 and 7.0 µg L-1were obtained for Zn2+ and Cd2+ ions, respectively. Relative standard deviation was 2.9 and 3.3, and enrichment factors 23.9 and 25.6, for Zn2+ and Cd2+ ions, respectively. The method enabled determination of low levels of Zn2+ and Cd2+ ions in urine, blood serum and water samples.

  20. Selective cloud point extraction and preconcentration of trace amounts of silver as a dithizone complex prior to flame atomic absorption spectrometric determination

    Energy Technology Data Exchange (ETDEWEB)

    Manzoori, Jamshid L.; Karim-Nezhad, Ghasem

    2003-05-19

    Dithizone (diphenylthiocarbazone) was used as a complexing agent in cloud point extraction for the first time and applied for selective preconcentration of trace amounts of silver. The analyte in the initial aqueous solution was acidified with sulfuric acid (pH<1) and 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 tetrahydrofuran (THF) and the analyte determined in the enriched solution by flame atomic absorption spectrometry. After optimization of the complexation and extraction conditions, a preconcentration factor of 43 was obtained for only 10 ml of sample. The analytical curve was linear in the range of 3-200 ng ml{sup -1} and the limit of detection was 0.56 ng ml{sup -1}. The proposed method was applied to the determination of silver in water samples.

  1. Solvent microextraction-flame atomic absorption spectrometry (SME-FAAS) for determination of ultratrace amounts of cadmium in meat and fish samples.

    Science.gov (United States)

    Goudarzi, Nasser

    2009-02-11

    A simple, low cost and highly sensitive method based on solvent microextraction (SME) for separation/preconcentration and flame atomic absorption spectrometry (FAAS) was proposed for the determination of ultratrace amounts of cadmium in meat and fish samples. The analytical procedure involved the formation of a hydrophobic complex by mixing the analyte solution with an ammonium pyrrolidinedithiocarbamate (APDC) solution. In suitable conditions, the complex of cadmium-APDC entered the micro organic phase, and thus, separation of the analyte from the matrix was achieved. Under optimal chemical and instrumental conditions, a detection limit (3 sigma) of 0.8 ng L(-1) and an enrichment factor of 93 were achieved. The relative standard deviation for the method was found to be 2.2% for Cd. The interference effects of some anions and cations were also investigated. The developed method has been applied to the determination of trace Cd in meat and fish samples.

  2. Evaluation of cadmium in greenhouse soils and agricultural products of Jiroft (Iran) using microwave digestion prior to atomic absorption spectrometry determination.

    Science.gov (United States)

    Afzali, Daryoush; Fathirad, Fariba; Afzali, Zahra; Majdzadeh-Kermani, Seyed Mohammad Javad

    2015-03-01

    This study determines total levels of potentially toxic trace element, Cd (II) in Jiroft (Kerman, Iran) greenhouse soil and agricultural products that are grown in these greenhouses (tomatoes and cucumbers), and the comparison with soil outside of greenhouse using microwave digestion prior to flame atomic absorption spectrometry determination. The results show that the cadmium concentration in greenhouse soil is 0.9-1.9 mg kg(-1) and out of greenhouse is 0.4-1.0 mg kg(-1). Also, cadmium concentration range in tomatoes and cucumbers is about 0.07-0.40 mg kg(-1). The obtained results show that the concentration of this metal in greenhouse soil is higher than outside soil samples and is below the safe limit.

  3. A simple and fast ultrasound-assisted extraction procedure for Fe and Zn determination in milk-based infant formulas using flame atomic absorption spectrometry (FAAS).

    Science.gov (United States)

    Machado, Ignacio; Bergmann, Gabriela; Pistón, Mariela

    2016-03-01

    A simple and fast ultrasound-assisted procedure for the determination of iron and zinc in infant formulas is presented. The analytical determinations were carried out by flame atomic absorption spectrometry. Multivariate experiments were performed for optimization; in addition, a comparative study was carried out using two ultrasonic devices. A method using an ultrasonic bath was selected because several samples can be prepared simultaneously, and there is less contamination risk. Analytical precision (sr(%)) was 3.3% and 4.1% for iron and zinc, respectively. Trueness was assessed using a reference material and by comparison of the results obtained analyzing commercial samples using a reference method. The results were statistically equivalent to the certified values and in good agreement with those obtained using the reference method. The proposed method can be easily implemented in laboratories for routine analysis with the advantage of being rapid and in agreement with green chemistry.

  4. Ultrasound-assisted emulsification-microextraction combined with graphite furnace atomic absorption spectrometry for the determination of trace lead in water

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Hongmei; Zhang, Yu; Qiu, Bocheng; Li, Wenhua [College of Science, Nanjing Agricultural University, Nan Jing (China)

    2012-04-15

    The ultrasound-assisted emulsification-microextraction (USAEME) method was combined with graphite furnace atomic absorption spectrometry (GFAAS) for the determination of trace Pb using dithizone (H{sup 2}DZ) as chelating reagent. Some effective parameters influenced the detection and microextraction, such as ashing temperature and atomization temperature, pH, extraction solvent, sample volume, extraction time, and extraction temperature were selected and optimized. After extraction, the calibration curves for Pb was in the concentration range of 0.1-10 ng mL{sup -1}, and the linear equation was y = 0.097 x + 0.023 (R = 0.99). Under the optimized conditions, the detection limit of the method was 20 pg mL{sup -1} with an enrichment factor of 70 and the relative standards deviation (RSD) for seven determinations of 1 ng mL{sup -1} Pb was 11%. The proposed method was successfully applied to determine trace Pb in Yueya Lake water, pond water, and spiked samples. Furthermore, a certified reference material of Environment Water (GBW08607) was analyzed and the determined value was in good agreement with the certified value, which showed the accuracy, recovery, and applicability of the reported method. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Determination of mercury in airborne particulate matter collected on glass fiber filters using high-resolution continuum source graphite furnace atomic absorption spectrometry and direct solid sampling

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Rennan G.O., E-mail: rgoa01@terra.com.br [Laboratorio de Quimica Analitica Ambiental, Departamento de Quimica, Universidade Federal de Sergipe, Campus Sao Cristovao, 49.100-000, Sao Cristovao, SE (Brazil); Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Vignola, Fabiola; Castilho, Ivan N.B. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Borges, Daniel L.G.; Welz, Bernhard [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil); Vale, Maria Goreti R. [Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil); Instituto de Quimica, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, RS (Brazil); Smichowski, Patricia [Comision Nacional de Energia Atomica (CNEA) and Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires (Argentina); Ferreira, Sergio L.C. [Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil); Instituto de Quimica, Universidade Federal da Bahia, 40170-290, Salvador, BA (Brazil); Becker-Ross, Helmut [Leibniz-Institut fuer Analytische Wissenschaften-ISAS-e.V., Department Berlin, 12489 Berlin (Germany)

    2011-05-15

    A study has been undertaken to assess the capability of high-resolution continuum source graphite furnace atomic absorption spectrometry for the determination of mercury in airborne particulate matter (APM) collected on glass fiber filters using direct solid sampling. The main Hg absorption line at 253.652 nm was used for all determinations. The certified reference material NIST SRM 1648 (Urban Particulate Matter) was used to check the accuracy of the method, and good agreement was obtained between published and determined values. The characteristic mass was 22 pg Hg. The limit of detection (3{sigma}), based on ten atomizations of an unexposed filter, was 40 ng g{sup -1}, corresponding to 0.12 ng m{sup -3} in the air for a typical air volume of 1440 m{sup 3} collected within 24 h. The limit of quantification was 150 ng g{sup -1}, equivalent to 0.41 ng m{sup -3} in the air. The repeatability of measurements was better than 17% RSD (n = 5). Mercury concentrations found in filter samples loaded with APM collected in Buenos Aires, Argentina, were between < 40 ng g{sup -1} and 381 {+-} 24 ng g{sup -1}. These values correspond to a mercury concentration in the air between < 0.12 ng m{sup -3} and 1.47 {+-} 0.09 ng m{sup -3}. The proposed procedure was found to be simple, fast and reliable, and suitable as a screening procedure for the determination of mercury in APM samples.

  6. Study of ammonium molybdate to minimize the phosphate interference in the selenium determination by electrothermal atomic absorption spectrometry with deuterium background correction

    Science.gov (United States)

    Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Adela

    2002-02-01

    The use of ammonium molybdate to minimize the phosphate interference when measuring selenium by electrothermal atomic absorption spectrometry (ETAAS) with deuterium background correction was evaluated. Ammonium molybdate did not produce a selenium thermal stabilization; however, the presence of ammonium molybdate decreased the phosphate interference. The study was carried out with mussel acid digests and mussel slurries. Pd-Mg(NO 3) 2 was used as a chemical modifier at optimum concentrations of 300 and 250 mg l -1, respectively, yielding optimum pyrolysis and atomization temperatures of 1200 and 2100 °C, respectively. A yellow solid (ammonium molybdophosphate) was obtained when adding ammonium molybdate to mussel acid digest solutions. This precipitate can be removed after centrifugation prior to ETAAS determination. Additionally, studies on the sampling of the solid ammonium molybdophosphate (AMP) together with the liquid phase, as a slurry, were also developed. The volatilization of the solid AMP was not reached at temperatures lower than 2500 °C. By this way, phosphate, as AMP, is not present in the vapor phase at the atomization temperature (2100 °C), yielding a reduction of the spectral interference by phosphate. The proposed method was validated analyzing three reference materials of marine origin (DORM-1, DOLT-1 and TORT-1). Good agreement with the certified selenium contents was reached for all cases.

  7. Use of sodium tungstate as a permanent chemical modifier for slurry sampling electrothermal atomic absorption spectrometric determination of indium in soils

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Garcia, Ignacio; Rivas, Ricardo E.; Hernandez-Cordoba, Manuel [University of Murcia, Department of Analytical Chemistry, Faculty of Chemistry, Murcia (Spain)

    2008-06-15

    A number of chemical modifiers have been assessed for the direct determination of indium in soils using electrothermal atomic absorption spectrometry and slurry sampling. The best results were obtained when the graphite atomizer was impregnated with sodium tungstate, which acts as a permanent chemical modifier. Slurries were prepared by suspending 100 mg sample in a solution containing 1% (v/v) concentrated nitric acid and 10% (v/v) concentrated hydrofluoric acid and then 15-{mu}L aliquots were directly introduced into the atomizer. Standard indium solutions prepared in the suspension medium in the range 4-80 {mu}g L{sup -1} indium were used for calibration. The relative standard deviation for ten consecutive measurements of a 40 {mu}g L{sup -1} indium solution was 2.8%. The limit of detection in soils was 0.1 {mu}g g{sup -1}. The reliability of the procedures was confirmed by analysing two standard reference materials and by using an alternative procedure. (orig.)

  8. Ultratrace determination of arsenic in water samples by electrothermal atomic absorption spectrometry after pre-concentration with Mg-Al-Fe ternary layered double hydroxide nano-sorbent.

    Science.gov (United States)

    Abdolmohammad-Zadeh, Hossein; Jouyban, Abolghasem; Amini, Roghayeh

    2013-11-15

    A selective solid phase extraction method, based on nano-structured Mg-Al-Fe(NO3(-)) ternary layered double hydroxide as a sorbent, is developed for the pre-concentration of ultra-trace levels of arsenic (As) prior to determination by electrothermal atomic absorption spectrometry. It is found that both As(III) and As(V) could be quantitatively retained on the sorbent within a wide pH range of 4-12. Accordingly, the presented method is applied to determination of total inorganic As in aqueous solutions. Maximum analytical signal of As is achieved when the pyrolysis and atomization temperatures are close to 900 °C and 2300 °C, respectively. Several variables affecting the extraction efficiency including pH, sample flow rate, amount of nano-sorbent, elution conditions and sample volume are optimized. Under the optimized conditions, the limit of detection (3Sb/m) and the relative standard deviation are 4.6 pg mL(-1) and 3.9%, respectively. The calibration graph is linear in the range of 15.0-650 pg mL(-1) with a correlation coefficient of 0.9979, sorption capacity and pre-concentration factor are 8.68 mg g(-1) and 300, respectively. The developed method is validated by the analysis of a standard reference material (SRM 1643e) and is successfully applied to the determination of ultra-trace amounts of As in different water samples.

  9. Determination of total selenium content in sediments and natural water by graphite furnace-atomic absorption spectroscopy after collection as a selenium(IV) complex on activated carbon.

    Science.gov (United States)

    Kubota, T; Suzuki, K; Okutani, T

    1995-07-01

    A trace level of Se was collected on activated carbon (AC) as the Se(IV)-3-phenyl-5-mercapto-1,3,4-thiadiazole-2(3H)-thione (Bismuthiol II) complex. The AC was directly introduced as an AC-suspension into the graphite tube atomizer and the Se concentration was determined by atomic absorption spectroscopy (T. Okutani, T. Kubota, N. Sugiyama and Y. Turuta, Nippon Kagaku Kaishi, (1991) 375). The amount of Se in heavily contaminated samples including sediment, lake water and seawater was determined using this method. The sediments were digested with HNO(3)HClO(4)HF and the interference from AlF(3) was removed using H(3)BO(3)HClO(4). Lake water and seawater were acidified with H(2)SO(4) and digested with KMnO(4). The Se concentrations of these samples were determined by this method with satisfactory results. The above method is simple, rapid and applicable to heavily contaminated samples.

  10. Multiwalled carbon nanotubes as a sorbent material for the solid phase extraction of lead from urine and subsequent determination by electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Peña Crecente, Rosa M.; Lovera, Carlha Gutiérrez; García, Julia Barciela; Méndez, Jennifer Álvarez; Martín, Sagrario García; Latorre, Carlos Herrero

    2014-11-01

    The determination of lead in urine is a way of monitoring the chemical exposure to this metal. In the present paper, a new method for the Pb determination by electrothermal atomic absorption spectrometry (ETAAS) in urine at low levels has been developed. Lead was separated from the undesirable urine matrix by means of a solid phase extraction (SPE) procedure. Oxidized multiwalled carbon nanotubes have been used as a sorbent material. Lead from urine was retained at pH 4.0 and was quantitatively eluted using a 0.7 M nitric acid solution and was subsequently measured by ETAAS. The effects of parameters that influence the adsorption-elution process (such as pH, eluent volume and concentration, sampling and elution flow rates) and the atomic spectrometry conditions have been studied by means of different factorial design strategies. Under the optimized conditions, the detection and quantification limits obtained were 0.08 and 0.26 μg Pb L- 1, respectively. The results demonstrate the absence of a urine matrix effect and this is the consequence of the SPE process carried out. Therefore, the developed method is useful for the analysis of Pb at low levels in real samples without the influence of other urine components. The proposed method was applied to the determination of lead in urine samples of unexposed healthy people and satisfactory results were obtained (in the range 3.64-22.9 μg Pb L- 1).

  11. [Digestion-flame atomic absorption spectroscopy].

    Science.gov (United States)

    Xu, Liang; Hu, Jian-Guo; Liu, Rui-Ping; Wang, Zhi-Min; Narenhua

    2008-01-01

    A microwave digestion-flame atomic absorption spectroscopy (FAAS) method was developed for the determination of metal elements Na, Zn, Cu, Fe, Mn, Ca and Mg in Mongolian patents. The instrument parameters for the determination were optimized, and the appropriate digestion solvent was selected. The recovery of the method was between 95.8% and 104.3%, and the RSD was between 1.6% and 4.2%. The accuracy and precision of the method was tested by comparing the values obtained from the determination of the standard sample, bush twigs and leaves (GSV-1) by this method with the reference values of GSV-1. The determination results were found to be basically consistent with the reference values. The microwave digestion technique was applied to process the samples, and the experimental results showed that compared to the traditional wet method, the present method has the merits of simplicity, saving agents, rapidness, and non-polluting. The method was accurate and reliable, and could be used to determine the contents of seven kinds of metal elements in mongolian patents.

  12. Absorption imaging of a single atom

    CERN Document Server

    Streed, E W; Norton, B G; Kielpinski, D

    2012-01-01

    Absorption imaging has played a key role in the advancement of science from van Leeuwenhoek's discovery of red blood cells to modern observations of dust clouds in stellar nebula. Here we show the first absorption imaging of a single atom isolated in vacuum. The simplicity of this system lets us compare our results directly to quantum theory, unlike recent work on absorption imaging of single molecules. The observed image contrast of 3.1(3)% achieved the maximum allowed by quantum theory for our setup, while the imaging resolution was on the order of the 370 nm illumination wavelength. The absorption of photons by single atoms is of immediate interest for quantum information processing (QIP). Our results also point out new opportunities in imaging of light-sensitive samples both in the optical and x-ray regimes. In particular, the dynamics of chromatin in living cells could be imaged without delivering a lethal UV dose.

  13. An improved method for the determination of trace levels of arsenic and antimony in geological materials by automated hydride generation-atomic absorption spectroscopy

    Science.gov (United States)

    Crock, J.G.; Lichte, F.E.

    1982-01-01

    An improved, automated method for the determination of arsenic and antimony in geological materials is described. After digestion of the material in sulfuric, nitric, hydrofluoric and perchloric acids, a hydrochloric acid solution of the sample is automatically mixed with reducing agents, acidified with additional hydrochloric acid, and treated with a sodium tetrahydroborate solution to form arsine and stibine. The hydrides are decomposed in a heated quartz tube in the optical path of an atomic absorption spectrometer. The absorbance peak height for arsenic or antimony is measured. Interferences that exist are minimized to the point where most geological materials including coals, soils, coal ashes, rocks and sediments can be analyzed directly without use of standard additions. The relative standard deviation of the digestion and the instrumental procedure is less than 2% at the 50 ??g l-1 As or Sb level. The reagent-blank detection limit is 0.2 ??g l-1 As or Sb. ?? 1982.

  14. Development a novel supramolecular solvent microextraction procedure for copper in environmental samples and its determination by microsampling flame atomic absorption spectrometry.

    Science.gov (United States)

    Yilmaz, Erkan; Soylak, Mustafa

    2014-08-01

    A supramolecular solvent (Ss) made up of reverse micelles of 1-decanol in tetrahydrofuran (THF): water was used for the fast and selective microextraction of Cu(II) prior to its determination by microsampling flame atomic absorption spectrometry (FAAS). Cu(II) was complexed with dimethyl dithiocarbamate (DMDC) to obtain hydrophobic complex and extracted to supramolecular solvent phase. The influences of some analytical parameters including pH, type and volume of supramolecular solvent, amount of complexing agent, ultrasonication and centrifuge time and sample volume were investigated. The effects of matrix components were also examined. The detection limit (LOD) and the quantification limit (LOQ) were 0.52µg L(-1) and 1.71µg L(-1) respectively. An preconcentration factor was obtained as 60 and the relative standard deviation was copper in food and water samples with satisfactory results.

  15. 原子吸收法快速测定燃油中的铝%Rapid Determination of Aluminium in Fuel Oil by Atomic-absorption Spectrophotometry

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The determination of aluminium in fuel oil by means of the technique of direct dilution using a mixed-solvent system, inorganic aluminiun standard and atomic absorption spectrophotometry is researched. Good recoveries of aluminium added to fuel oil were demonstrated. Relative standard deviation of 3.6% was reached.%采用无机铝标准物和混合溶剂系统直接稀释-原子吸收法测定燃油中铝,回收率达92.4%,相对标准偏差为3.6%,特征质量浓度为0.85μg/mL.

  16. Extraction and preconcentration of selenium from aqueous solutions and its determination in water and hair samples by atomic-absorption spectrophotometry.

    Science.gov (United States)

    Ejaz, M; Qureshi, M A

    1987-03-01

    Several organic solvents, including benzene, xylene, toluene, nitrobenzene, chloroform, carbon tetrachloride, chlorobenzene and high molecular-weight pyridines such as 4-(5-nonyl)pyridine, 2-hexyl-pyridine and benzylpyridine have been investigated as components of systems for the extraction and preconcentration of selenium from nitric acid solutions containing iodide. The results are discussed in terms of choice of reagents and the acid and iodide concentrations, and of several other parameters affecting the extraction. The utility of the method for separation of selenium from aqueous solution has been evaluated. The method has been used for preconcentration of trace levels of selenium from water and hair samples for determination by atomic-absorption spectrophotometry.

  17. Separation/preconcentration of trace Pb(II and Cd(II with 2-mercaptobenzothiazole impregnated Amberlite XAD-1180 resin and their determination by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Şerife Tokalıoğlu

    2017-01-01

    Full Text Available A new chelating resin, 2-mercaptobenzothiazole loaded Amberlite XAD-1180 was prepared and used for separation and preconcentration of Cd(II and Pb(II ions prior to their determinations by flame atomic absorption spectrometry. The optimum pH for simultaneous retention of the elements and the best elution means for their simultaneous elution were 9.5 and 2 mol L−1 HNO3, respectively. The detection limits for Cd(II and Pb(II were 0.35 and 5.0 μg L−1, respectively. The accuracy of the method was confırmed both by analyzing the certified reference material (RM 8704 Buffalo river sediment and performing recovery studies.

  18. Determination of tin, vanadium, iron, and molybdenum in various matrices by atomic absorption spectrometry using a simultaneous liquid-liquid extraction procedure.

    Science.gov (United States)

    Sánchez-Viñas, M; Bagur, G M; Gázquez, D; Camino, M; Romero, R

    1999-01-01

    An atomic-absorption spectrometric method is described for the determination of tin, vanadium, iron, and molybdenum in two certified reference materials, food samples, and petroleum crude. After treatment with acids, these elements are separated from matrix elements by simultaneous solvent extraction of 5,5'-methylenedisalicylohydroxamic acid complexes from HCl/NaClO4 solution into an isobutyl methyl ketone/tributyl phosphate solution. The detection limits range from 0.018 to 0.19 microg/mL (n = 3), and the relative standard deviations do not exceed 2.0% at levels of 0.5, 0.6, 2.0, and 7.0 microg/mL of Fe, Mo, V, and Sn, respectively. The method is selective and suffers only from interference by Zr(IV), Ti(IV), Th(IV), W(VI), PO4(3-), and F-.

  19. Peat as a natural solid-phase for copper preconcentration and determination in a multicommuted flow system coupled to flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Gonzales, A.P.S. [Centro de Ciencias Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adelia, 166, 09210-170 Santo Andre (Brazil); Firmino, M.A. [Departamento de Engenharia de Materiais, Escola de Engenharia, Universidade Presbiteriana Mackenzie, Rua da Consolacao, 930, 01302-970 Sao Paulo (Brazil); Nomura, C.S. [Centro de Ciencias Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adelia, 166, 09210-170 Santo Andre (Brazil); Rocha, F.R.P.; Oliveira, P.V. [Departamento de Quimica Fundamental, Instituto de Quimica, Universidade de Sao Paulo, Av. Prof. Lineu Prestes, 748, 05508-000 Sao Paulo (Brazil); Gaubeur, I. [Centro de Ciencias Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adelia, 166, 09210-170 Santo Andre (Brazil)], E-mail: ivanise.gaubeur@ufabc.edu.br

    2009-03-23

    The physical and chemical characteristics of peat were assessed through measurement of pH, percentage of organic matter, cationic exchange capacity (CEC), elemental analysis, infrared spectroscopy and quantitative analysis of metals by ICP OES. Despite the material showed to be very acid in view of the percentage of organic matter, its CEC was significant, showing potential for retention of metal ions. This characteristic was exploited by coupling a peat mini-column to a flow system based on the multicommutation approach for the in-line copper concentration prior to flame atomic absorption spectrometric determination. Cu(II) ions were adsorbed at pH 4.5 and eluted with 0.50 mol L{sup -1} HNO{sub 3}. The influence of chemical and hydrodynamic parameters, such as sample pH, buffer concentration, eluent type and concentration, sample flow-rate and preconcentration time were investigated. Under the optimized conditions, a linear response was observed between 16 and 100 {mu}g L{sup -1}, with a detection limit estimated as 3 {mu}g L{sup -1} at the 99.7% confidence level and an enrichment factor of 16. The relative standard deviation was estimated as 3.3% (n = 20). The mini-column was used for at least 100 sampling cycles without significant variation in the analytical response. Recoveries from copper spiked to lake water or groundwater as well as concentrates used in hemodialysis were in the 97.3-111% range. The results obtained for copper determination in these samples agreed with those achieved by graphite furnace atomic absorption spectrometry (GFAAS) at the 95% confidence level.

  20. Direct and simultaneous determination of Cr and Fe in crude oil using high-resolution continuum source graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Dittert, Ingrid M. [Departamento de Quimica, Universidade Federal de Santa Catarina, Campus Universitario, Trindade, 88040-900, Florianopolis, SC (Brazil); Silva, Jessee S.A. [Centro Federal de Educacao Tecnologica de Santa Catarina, Florianopolis, SC (Brazil); Araujo, Rennan G.O. [Departamento de Quimica, Universidade Federal de Santa Catarina, Campus Universitario, Trindade, 88040-900, Florianopolis, SC (Brazil)], E-mail: rgoa01@terra.com.br; Curtius, Adilson J.; Welz, Bernhard [Departamento de Quimica, Universidade Federal de Santa Catarina, Campus Universitario, Trindade, 88040-900, Florianopolis, SC (Brazil); Becker-Ross, Helmut [ISAS, Institute for Analytical Sciences, Department of Interface Spectroscopy, Albert-Einstein-Str. 9, 12489 Berlin (Germany)

    2009-06-15

    A simple, fast and sensitive direct method for the simultaneous determination of Cr and Fe in crude oil samples is proposed using high-resolution continuum source graphite furnace atomic absorption spectrometry. No sample preparation is used except for a 10-minute homogenization in an ultrasonic bath. Aliquots of 0.1-4 mg of the samples are weighed onto solid sampling platforms and analyzed directly using aqueous standards for calibration. The simultaneous determination was possible because there is a secondary Fe line at 358.120 nm in the vicinity of the most sensitive Cr line at 357.868 nm, and both absorption lines were within the wavelength interval covered by the linear charge-coupled device array detector. It has also been of advantage that the sensitivity ratio between the two analytical lines corresponded roughly to the concentration ratio of the two elements found in crude oil, and that both analytes have very similar volatility, so that no compromises had to be made regarding pyrolysis and atomization temperatures. Two oil reference materials have been analyzed and the results were in agreement with the certified or reported values. Characteristic masses of 3.6 pg and 0.5 ng were obtained for Cr and Fe, respectively. The limits of detection (3{sigma}, n = 10) were 1 {mu}g kg{sup - 1} for Cr and 0.6 mg kg{sup - 1} for Fe, and the precision, expressed as the relative standard deviation, ranged from 4 to 20%, which is often acceptable for a rapid direct analytical procedure. Five crude oils samples were analyzed.

  1. Direct and simultaneous determination of Cr and Fe in crude oil using high-resolution continuum source graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Dittert, Ingrid M.; Silva, Jessee S. A.; Araujo, Rennan G. O.; Curtius, Adilson J.; Welz, Bernhard; Becker-Ross, Helmut

    2009-06-01

    A simple, fast and sensitive direct method for the simultaneous determination of Cr and Fe in crude oil samples is proposed using high-resolution continuum source graphite furnace atomic absorption spectrometry. No sample preparation is used except for a 10-minute homogenization in an ultrasonic bath. Aliquots of 0.1-4 mg of the samples are weighed onto solid sampling platforms and analyzed directly using aqueous standards for calibration. The simultaneous determination was possible because there is a secondary Fe line at 358.120 nm in the vicinity of the most sensitive Cr line at 357.868 nm, and both absorption lines were within the wavelength interval covered by the linear charge-coupled device array detector. It has also been of advantage that the sensitivity ratio between the two analytical lines corresponded roughly to the concentration ratio of the two elements found in crude oil, and that both analytes have very similar volatility, so that no compromises had to be made regarding pyrolysis and atomization temperatures. Two oil reference materials have been analyzed and the results were in agreement with the certified or reported values. Characteristic masses of 3.6 pg and 0.5 ng were obtained for Cr and Fe, respectively. The limits of detection (3 σ, n = 10) were 1 µg kg - 1 for Cr and 0.6 mg kg - 1 for Fe, and the precision, expressed as the relative standard deviation, ranged from 4 to 20%, which is often acceptable for a rapid direct analytical procedure. Five crude oils samples were analyzed.

  2. The use of silver nanoparticles as an effective modifier for the determination of arsenic and antimony by electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Gunduz, S.; Akman, S.; Baysal, A.; Kahraman, M.

    2010-04-01

    Silver nanoparticles (AgNPs) were proposed as a new chemical modifier for the elimination of interferences when determining arsenic and antimony in aqueous NaCl or Na 2SO 4 solutions and in sea-water by electrothermal atomic absorption spectrometry. For this purpose, the AgNPs were prepared simply by reducing silver nitrate with sodium citrate. The effects of pyrolysis and atomization temperatures and the amounts of interferents and modifiers on the sensitivities of these elements were investigated. In the presence of the proposed modifier, a pyrolysis temperature of at least 1100 °C for arsenic and 900 °C for antimony could be applied without the loss of analytes, and the interferences were greatly reduced to allow for interference-free determination. The detection limits ( N = 10, 3 σ) for arsenic and antimony were 0.022 ng and 0.046 ng, respectively. AgNPs are cheaper and more available compared to many other modifiers. No background was detected, and the blank values were negligible.

  3. Freon (CHF3)-assisted atomization for the determination of titanium using ultrasonic slurry sampling-graphite furnace atomic absorption spectrometry (USS-GFAAS): a simple and advantageous method for solid samples.

    Science.gov (United States)

    Asfaw, Alemayehu; Wibetoe, Grethe

    2004-06-01

    A simple and advantageous method for the determination of titanium using graphite furnace atomic absorption spectrometry with slurry sampling has been developed. Titanium is one of the refractory elements that form thermally stable carbides in the graphite tube, which leads to severe memory effects. Trifluoromethane (Freon-23) was applied in the purge gas during the atomization step or alternatively just prior to the atomization to successfully eliminate the problems of carbide formation and increase the lifetime of the furnace tube which could be used for more than 600 heating cycles. A flow rate of 40 mL min(-1) (5% of Freon in argon) was used to obtain symmetrical peaks with no tailing. However, when the gas flow rate was too high (250 mL min(-1)) the peak-tailing and memory effects reappeared. Ti was determined in various materials covering a wide range of concentrations, from 2.8 microg g(-1) to 12% (m/m) Ti. The accuracy of the method was confirmed by analyzing certified reference materials (CRMs) or by comparing the results with those obtained using inductively coupled plasma-atomic emission spectrometry (ICP-AES) after decomposition of the samples. The materials analyzed were soil, plant, human hair, coal, urban particulate matters, toothpaste, and powdered paint.

  4. Multiwalled carbon nanotubes as a sorbent material for the solid phase extraction of lead from urine and subsequent determination by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Peña Crecente, Rosa M.; Lovera, Carlha Gutiérrez; García, Julia Barciela; Méndez, Jennifer Álvarez; Martín, Sagrario García; Latorre, Carlos Herrero, E-mail: carlos.herrero@usc.es

    2014-11-01

    The determination of lead in urine is a way of monitoring the chemical exposure to this metal. In the present paper, a new method for the Pb determination by electrothermal atomic absorption spectrometry (ETAAS) in urine at low levels has been developed. Lead was separated from the undesirable urine matrix by means of a solid phase extraction (SPE) procedure. Oxidized multiwalled carbon nanotubes have been used as a sorbent material. Lead from urine was retained at pH 4.0 and was quantitatively eluted using a 0.7 M nitric acid solution and was subsequently measured by ETAAS. The effects of parameters that influence the adsorption–elution process (such as pH, eluent volume and concentration, sampling and elution flow rates) and the atomic spectrometry conditions have been studied by means of different factorial design strategies. Under the optimized conditions, the detection and quantification limits obtained were 0.08 and 0.26 μg Pb L{sup −1}, respectively. The results demonstrate the absence of a urine matrix effect and this is the consequence of the SPE process carried out. Therefore, the developed method is useful for the analysis of Pb at low levels in real samples without the influence of other urine components. The proposed method was applied to the determination of lead in urine samples of unexposed healthy people and satisfactory results were obtained (in the range 3.64–22.9 μg Pb L{sup −1}). - Highlights: • Lead determination in urine using a solid phase extraction procedure followed by ETAAS • Carbon nanotubes as SPE adsorbent for Pb in urine • Matrix elimination for the Pb determination in urine by using SPE based on carbon nanotubes • The detection limit was 0.08 μg Pb L{sup −1}.

  5. Simultaneous determination of iron and nickel in fluoropolymers by solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Soares, Bruno M; Santos, Rafael F; Bolzan, Rodrigo C; Muller, Edson I; Primel, Ednei G; Duarte, Fabio A

    2016-11-01

    This paper reports the development of a method of simultaneous determination of iron and nickel in fluoropolymers by high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) with direct solid sampling. In order to carry out simultaneous measurements, both the main resonance line of nickel (232.003nm) and the adjacent secondary line of iron (232.036nm) were monitored in the same spectral window. The proposed method was optimized with a perfluoroalkoxy (PFA) sample and was applied to the determination of iron and nickel in fluorinated ethylene propylene (FEP) and modified polytetrafluoroethylene (PTFE-TFM) samples. Pyrolysis and atomization temperatures, as well as the use of Pd and H2 (during pyrolysis) as chemical modifiers, were carefully investigated. Compromise temperatures for pyrolysis and atomization of both analytes were achieved at 800 and 2300°C, respectively, using only 0.5Lmin(-1) H2 as chemical modifier during pyrolysis. Calibration curves were performed with aqueous standards by using a single solution which contained both analytes. Limits of detection were 221 and 9.6ngg(-1) for iron and nickel, respectively. Analyte concentrations in all samples ranged from 3.53 to 12.4µgg(-1) for iron and from 37 to 78ngg(-1) for nickel, with relative standard deviation less than 19%. Accuracy was evaluated by comparing these results with those obtained by inductively coupled plasma mass spectrometry after sample digestion by microwave-induced combustion and no significant statistical difference was observed.

  6. Simultaneous determination of Cr, Ni and V in urine by electrothermal atomic absorption spectrometry (ET AAS); Determinacion simultanea de Cr, Ni y V en orina mediante et aas

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, Maria A.; Hermida, Jeymi [Universidad Central de Venezuela, Caracas (Venezuela, Bolivarian Republic of). Escuela de Quimica. Centro de Quimica Analitica

    2011-07-01

    A procedure for the simultaneous determination of Cr, Ni, and V in urine by electrothermal atomic absorption spectrometry (ET AAS) was optimized by factorial design, and performed at a pyrolysis and atomization temperatures of 1300 and 2500 deg C, respectively, using 15 {mu}g de Mg(NO{sub 3}){sub 2} as chemical modifier. Characteristics mass of 14, 6 and 220 {rho}g and detection limits of the method of 0.07, 0.38 and 0.75 {mu}g L{sup -1} were obtained for Cr, Ni and V respectively. The methodology was validated using a Liphochek Urine Metals Control sample (Bio-Rad) (P=0.05). The methodology was applied to samples of voluntary Venezuelan people, not environmentally exposed to specific emissions, and results ranging from < LOD-1.1 and 1.3-3.3 {mu}g L{sup -1} was observed for Cr and V, respectively, and not detectable levels for Ni. (author)

  7. Evaluation of solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry for direct determination of chromium in medicinal plants

    Energy Technology Data Exchange (ETDEWEB)

    Virgilio, Alex; Nobrega, Joaquim A. [Department of Chemistry, Federal University of Sao Carlos, Post Office Box 676, 13560-970, Sao Carlos-SP (Brazil); Rego, Jardes F. [Department of Analytical Chemistry, Institute of Chemistry, Sao Paulo State University-UNESP, Post Office Box 355, 14801-970, Araraquara-SP (Brazil); Neto, Jose A. Gomes, E-mail: anchieta@iq.unesp.br [Department of Analytical Chemistry, Institute of Chemistry, Sao Paulo State University-UNESP, Post Office Box 355, 14801-970, Araraquara-SP (Brazil)

    2012-12-01

    A method for Cr determination in medicinal plants using direct solid sampling graphite furnace high-resolution continuum source atomic absorption spectrometry was developed. Modifiers were dispensable. Pyrolysis and atomization temperatures were 1500 Degree-Sign C and 2400 Degree-Sign C, respectively. Slopes of calibration curves (50-750 pg Cr, R{sup 2} > 0.999) using aqueous and solid standards coincides in 96%, indicated feasibility of aqueous calibration for solid sampling of medicinal plants. Accuracy was checked by analysis of four plant certified reference materials. Results were in agreement at 95% confidence level with certified and non-certified values. Ten samples of medicinal plants were analyzed and Cr contents were in the 1.3-17.7 {mu}g g{sup -1} Cr range. The highest RSD (n = 5) was 15.4% for the sample Melissa officinalis containing 13.9 {+-} 2.1 {mu}g g{sup -1} Cr. The limit of detection was 3.3 ng g{sup -1} Cr. - Highlights: Black-Right-Pointing-Pointer Direct solid sampling is first time employed for Cr in plant materials. Black-Right-Pointing-Pointer Calibration curves with liquids and solids are coincident. Black-Right-Pointing-Pointer Microanalysis of plants for Cr is validated by reference materials. Black-Right-Pointing-Pointer The proposed HR-CS GF AAS method is environmental friendly.

  8. Evaluation of solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry for direct determination of chromium in medicinal plants

    Science.gov (United States)

    Virgilio, Alex; Nóbrega, Joaquim A.; Rêgo, Jardes F.; Neto, José A. Gomes

    2012-12-01

    A method for Cr determination in medicinal plants using direct solid sampling graphite furnace high-resolution continuum source atomic absorption spectrometry was developed. Modifiers were dispensable. Pyrolysis and atomization temperatures were 1500 °C and 2400 °C, respectively. Slopes of calibration curves (50-750 pg Cr, R2 > 0.999) using aqueous and solid standards coincides in 96%, indicated feasibility of aqueous calibration for solid sampling of medicinal plants. Accuracy was checked by analysis of four plant certified reference materials. Results were in agreement at 95% confidence level with certified and non-certified values. Ten samples of medicinal plants were analyzed and Cr contents were in the 1.3-17.7 μg g- 1 Cr range. The highest RSD (n = 5) was 15.4% for the sample Melissa officinalis containing 13.9 ± 2.1 μg g- 1 Cr. The limit of detection was 3.3 ng g- 1 Cr.

  9. Determination of cadmium and lead in urine samples after dispersive solid-liquid extraction on multiwalled carbon nanotubes by slurry sampling electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Álvarez Méndez, J.; Barciela García, J.; García Martín, S.; Peña Crecente, R. M.; Herrero Latorre, C.

    2015-04-01

    A new method for the determination of Cd and Pb in urine samples has been developed. The method involves dispersive solid-phase extraction (DSPE), slurry sampling (SS), and subsequent electrothermal atomic absorption spectrometry (ETAAS). Oxidized multiwalled carbon nanotubes (MWCNTs) were used as the sorbent material. The isolated MWCNT/analyte aggregates were treated with nitric acid to form a slurry and both metals were determined directly by injecting the slurry into the ETAAS-atomizer. The parameters that influence the adsorption of the metals on MWCNTs in the DSPE process, the formation and extraction of the slurry, and the ETAAS conditions were studied by different factorial design strategies. The detection and quantification limits obtained for Cd under optimized conditions were 9.7 and 32.3 ng L- 1, respectively, and for Pb these limits were 0.13 and 0.43 μg L- 1. The preconcentration factors achieved were 3.9 and 5.4. The RSD values (n = 10) were less than 4.1% and 5.9% for Cd and Pb, respectively. The accuracy of the method was assessed in recovery studies, with values in the range 96-102% obtained for Cd and 97-101% for Pb. In addition, the analysis of certified reference materials gave consistent results. The DSPE-SS-ETAAS method is a novel and useful strategy for the determination of Pb and Cd at low levels in human urine samples. The method is sensitive, fast, and free of matrix interferences, and it avoids the tedious and time-consuming on-column adsorption and elution steps associated with commonly used SPE procedures. The proposed method was used to determine Cd and Pb in urine samples of unexposed healthy people and satisfactory results were obtained.

  10. Direct determination of chromium in infant formulas employing high-resolution continuum source electrothermal atomic absorption spectrometry and solid sample analysis.

    Science.gov (United States)

    Silva, Arlene S; Brandao, Geovani C; Matos, Geraldo D; Ferreira, Sergio L C

    2015-11-01

    The present work proposed an analytical method for the direct determination of chromium in infant formulas employing the high-resolution continuum source electrothermal atomic absorption spectrometry combined with the solid sample analysis (SS-HR-CS ET AAS). Sample masses up to 2.0mg were directly weighted on a solid sampling platform and introduced into the graphite tube. In order to minimize the formation of carbonaceous residues and to improve the contact of the modifier solution with the solid sample, a volume of 10 µL of a solution containing 6% (v/v) H2O2, 20% (v/v) ethanol and 1% (v/v) HNO3 was added. The pyrolysis and atomization temperatures established were 1600 and 2400 °C, respectively, using magnesium as chemical modifier. The calibration technique was evaluated by comparing the slopes of calibration curves established using aqueous and solid standards. This test revealed that chromium can be determined employing the external calibration technique using aqueous standards. Under these conditions, the method developed allows the direct determination of chromium with limit of quantification of 11.5 ng g(-1), precision expressed as relative standard deviation (RSD) in the range of 4.0-17.9% (n=3) and a characteristic mass of 1.2 pg of chromium. The accuracy was confirmed by analysis of a certified reference material of tomato leaves furnished by National Institute of Standards and Technology. The method proposed was applied for the determination of chromium in five different infant formula samples. The chromium content found varied in the range of 33.9-58.1 ng g(-1) (n=3). These samples were also analyzed employing ICP-MS. A statistical test demonstrated that there is no significant difference between the results found by two methods. The chromium concentrations achieved are lower than the maximum limit permissible for chromium in foods by Brazilian Legislation.

  11. Direct determination of silicon in powdered aluminium oxide by use of slurry sampling with in situ fusion graphite-furnace atomic-absorption spectrometry.

    Science.gov (United States)

    Minami, H; Yoshida, T; Okutsu, K; Zhang, Q; Inoue, S; Atsuya, I

    2001-08-01

    A direct method for determination of silicon in powdered high-purity aluminium oxide samples, by slurry sampling with in situ fusion graphite-furnace atomic-absorption spectrometry (GF-AAS), has been established. A slurry sample was prepared by 10-min ultrasonication of a powdered sample in an aqueous solution containing both sodium carbonate and boric acid as a mixed flux. An appropriate portion of the slurry was introduced into a pyrolytic graphite furnace equipped with a platform. Silicon compounds to be determined and aluminium oxide were fused by the in situ fusion process with the flux in the furnace under optimized heating conditions, and the silicon absorbance was then measured directly. The calibration curve was prepared by use of a silicon standard solution containing the same concentration of the flux as the slurry sample. The accuracy of the proposed method was confirmed by analysis of certified reference materials. The proposed method gave statistically accurate values at the 95% confidence level. The detection limit was 3.3 microg g(-1) in solid samples, when 300 mg/20 mL slurry was prepared and a 10 microL portion of the slurry was measured. The precision of the determination (RSD for more than four separate determinations) was 14% and 2%, respectively, for levels of 10 and 100 microg g(-1) silicon in aluminium oxide.

  12. Validated method for the determination of platinum from a liposomal source (SPI-77) in human plasma using graphite furnace Zeeman atomic absorption spectrometry.

    Science.gov (United States)

    Meerum Terwogt, J M; Tibben, M M; Welbank, H; Schellens, J H; Beijnen, J H

    2000-02-01

    A sensitive analytical method based on flameless atomic absorption spectrometry with Zeeman correction has been validated for the quantitative determination in human plasma of platinum originating from cisplatin in a liposomal source, SPI-77. The performance of the method was acceptable over a sample concentration range of 0. 125-1.25 micromol platinum/L and the lower limit of quantification was determined to be 1.25 micromol platinum/L in undiluted clinical samples. The performance data of the assay were investigated using both a calibration curve with carboplatin in plasma ultrafiltrate and diluted human plasma samples spiked with SPI-77. The recoveries, between-day and the within-day precisions of both methods of calibration were not significantly different allowing carboplatin ultrafiltrate calibration standards to be used to quantify platinum derived from SPI-77 in human plasma. Apparently, the liposomal formulation had no significant influence on the determination of platinum. The usefulness of the presented method was demonstrated in a phase I clinical and pharmacokinetic study. In addition, in vitro experiments were carried out to determine the distribution of SPI-77 in blood. The results indicated that platinum from SPI-77 mainly concentrates in plasma and that binding to and/or endocytosis in red blood cells is negligible.

  13. RAPID AND SENSITIVE DETERMINATION OF PALLADIUM USING HOMOGENEOUS LIQUID-LIQUID MICROEXTRACTION VIA FLOTATION ASSISTANCE FOLLOWED BY GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROMETRY

    Directory of Open Access Journals (Sweden)

    Mohammad Rezaee

    2015-05-01

    Full Text Available A method for the determination of trace amounts of palladium was developed using homogeneous liquid-liquid microextraction via flotation assistance (HLLME-FA followed by graphite furnace atomic absorption spectrometry (GFAAS. Ammonium pyrrolidine dithiocarbamate (APDC was used as a complexing agent. This was applied to determine palladium in three types of water samples. In this study, a special extraction cell was designed to facilitate collection of the low-density solvent extraction. No centrifugation was required in this procedure. The water sample solution was added to the extraction cell which contained an appropriate mixture of extraction and homogeneous solvents. By using air flotation, the organic solvent was collected at the conical part of the designed cell. Parameters affecting extraction efficiency were investigated and optimized. Under the optimum conditions, the calibration graph was linear in the range of 1.0-200 µg L-1 with a limit of detection of 0.3 µg L-1. The performance of the method was evaluated for the extraction and determination of palladium in water samples and satisfactory results were obtained. In order to verify the accuracy of the approach, the standard addition method was applied for the determination of palladium in spiked synthetic samples and satisfactory results were obtained.

  14. A pre-concentration procedure using coprecipitation for determination of lead and iron in several samples using flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Saracoglu, S. [Erciyes University, Faculty of Education, 38039 Kayseri (Turkey); Soylak, M. [Erciyes University, Faculty of Science and Arts, Chemistry Department, 38039 Kayseri (Turkey)]. E-mail: soylak@erciyes.edu.tr; Peker, D.S. Kacar [Erciyes University, Faculty of Science and Arts, Chemistry Department, 38039 Kayseri (Turkey); Elci, L. [Pamukkale University, Faculty of Science and Arts, Chemistry Department, 20020 Denizli (Turkey); Santos, W.N.L. dos [Universidade Estadual de Santa Cruz lheus, Bahia (Brazil); Lemos, V.A. [Universidade Estadual do Sudoeste da Bahia, Nucleo de Quimica Analitica da Bahia (NQA), Laboratorio de Quimica Analitica (LQA), Campus de Jequie, 45200-000 Jequie, BA (Brazil); Ferreira, S.L.C. [Instituto de Quimica, Universidade Federal da Bahia, Campus Universitario de Ondina, 40.170-280 Salvador, BA (Brazil)

    2006-08-04

    The present paper proposes a pre-concentration procedure for determination of lead and iron in several samples by flame atomic absorption spectrometry. In it, lead(II) and iron(III) ions are coprecipitated using the violuric acid-copper(II) system as collector. Afterwards, the precipitate is dissolved with 1 M HNO{sub 3} solution and the metal ions are determined. The optimization step was performed using factorial design involving the variables: pH, violuric acid mass (VA) and copper concentration (Cu). Using the optimized experimental conditions, the proposed procedure allows the determination these metals with detection limits of 0.18 {mu}g L{sup -1} for iron and 0.16 {mu}g L{sup -1} for lead. The effects of foreign ions on the pre-concentration procedure were also evaluated and the results demonstrated that this method could be applied for determination of iron and lead in several real samples. The proposed method was successfully applied to the analysis of seawater, urine, mineral water, soil and physiological solution samples. The concentrations of lead and iron achieved in these samples agree well with others data reported in the literature.

  15. Bovine liver sample preparation and micro-homogeneity study for Cu and Zn determination by solid sampling electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, Cassiana S. [Instituto de Quimica, Universidade de Sao Paulo, CP 26077, Sao Paulo, SP 05513-970 (Brazil); Silva, Cintia S. [Instituto de Quimica, Universidade de Sao Paulo, CP 26077, Sao Paulo, SP 05513-970 (Brazil); Nogueira, Ana R.A. [Embrapa Pecuaria Sudeste, CP 339, Sao Carlos, SP 13560-970 (Brazil); Oliveira, Pedro V. [Instituto de Quimica, Universidade de Sao Paulo, CP 26077, Sao Paulo, SP 05513-970 (Brazil)]. E-mail: pvolivei@iq.usp.br

    2005-06-30

    This work describes a systematic study for the bovine liver sample preparation for Cu and Zn determination by solid sampling electrothermal atomic absorption spectrometry. The main parameters investigated were sample drying, grinding process, particle size, sample size, microsample homogeneity, and their relationship with the precision and accuracy of the method. A bovine liver sample was prepared using different drying procedures: (1) freeze drying, and (2) drying in a household microwave oven followed by drying in a stove at 60 deg. C until constant mass. Ball and cryogenic mills were used for grinding. Less sensitive wavelengths for Cu (216.5 nm) and Zn (307.6 nm), and Zeeman-based three-field background correction for Cu were used to diminish the sensitivities. The pyrolysis and atomization temperatures adopted were 1000 deg. C and 2300 deg. C for Cu, and 700 deg. C and 1700 deg. C for Zn, respectively. For both elements, it was possible to calibrate the spectrometer with aqueous solutions. The use of 250 {mu}g of W + 200 {mu}g of Rh as permanent chemical modifier was imperative for Zn. Under these conditions, the characteristic mass and detection limit were 1.4 ng and 1.6 ng for Cu, and 2.8 ng and 1.3 ng for Zn, respectively. The results showed good agreement (95% confidence level) for homogeneity of the entire material (> 200 mg) when the sample was dried in microwave/stove and ground in a cryogenic mill. The microsample homogeneity study showed that Zn is more dependent on the sample pretreatment than Cu. The bovine liver sample prepared in microwave/stove and ground in a cryogenic mill presented results with the lowest relative standard deviation for Cu than Zn. Good accuracy and precision were observed for bovine liver masses higher than 40 {mu}g for Cu and 30 {mu}g for Zn. The concentrations of Cu and Zn in the prepared bovine liver sample were 223 mg kg{sup -} {sup 1} and 128 mg kg{sup -} {sup 1}, respectively. The relative standard deviations were lower

  16. Hollow fiber based liquid-phase microextraction for the determination of mercury traces in water samples by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Garcia, Ignacio; Rivas, Ricardo E. [Department of Analytical Chemistry, Faculty of Chemistry, Regional Campus of International Excellence ' Campus Mare Nostrum' , University of Murcia, E-30071 Murcia (Spain); Hernandez-Cordoba, Manuel, E-mail: hcordoba@um.es [Department of Analytical Chemistry, Faculty of Chemistry, Regional Campus of International Excellence ' Campus Mare Nostrum' , University of Murcia, E-30071 Murcia (Spain)

    2012-09-19

    Highlight: Black-Right-Pointing-Pointer Hg (II) traces are preconcentrated by means of a three-phase liquid microextraction system. Black-Right-Pointing-Pointer PAN and ammonium iodide are used in the donor and acceptor phase, respectively. Black-Right-Pointing-Pointer Hollow-fiber pores are continuously fed with toluene placed in the lumen. Black-Right-Pointing-Pointer Mercuric ions can be measured in waters below the {mu}g L{sup -1} level. - Abstract: A three-phase liquid microextraction procedure for the determination of mercury at low concentrations is discussed. To the aqueous sample placed at pH 7 by means of a phosphate buffer, 0.002% (m/v) 1-(2-pyridylazo)-2-naphthol (PAN) is incorporated, and the mixture submitted to microextraction with a hollow-fiber impregnated with toluene and whose lumen contains a 0.05 mol L{sup -1} ammonium iodide solution. The final measurement of the extract is carried out by electrothermal atomic absorption spectrometry (300 Degree-Sign C and 1100 Degree-Sign C for the calcination and atomization temperatures, respectively). The pyrolytic graphite atomizer is coated electrolytically with palladium. An enrichment factor of 270, which results in a 0.06 {mu}g L{sup -1} mercury for the detection limit is obtained. The relative standard deviation at the 1 {mu}g L{sup -1} mercury level is 3.2% (n = 5). The reliability of the procedure is verified by analyzing waters as well as six certified reference materials.

  17. In situ emulsification microextraction using a dicationic ionic liquid followed by magnetic assisted physisorption for determination of lead prior to micro-sampling flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Shokri, Masood; Beiraghi, Asadollah [Faculty of Chemistry, Kharazmi University, Tehran (Iran, Islamic Republic of); Seidi, Shahram, E-mail: s.seidi@kntu.ac.ir [Department of Analytical Chemistry, Faculty of Chemistry, K.N. Toosi University of Technology, Tehran (Iran, Islamic Republic of)

    2015-08-19

    For the first time, a simple and efficient in situ emulsification microextraction method using a dicationic ionic liquid followed by magnetic assisted physisorption was presented to determine trace amounts of lead. In this method, 400 μL of 1.0 mol L{sup −1} lithium bis (trifluoromethylsulfonyl) imide aqueous solution, Li[NTf{sub 2}], was added into the sample solution containing 100 μL of 1.0 mol L{sup −1} 1,3-(propyl-1,3-diyl) bis (3-methylimidazolium) chloride, [pbmim]Cl{sub 2}, to form a water immiscible ionic liquid, [pbmim][NTf{sub 2}]{sub 2}. This new in situ formed dicationic ionic liquid was applied as the acceptor phase to extract the lead-ammonium pyrrolidinedithiocarbamate (Pb-APDC) complexes from the sample solution. Subsequently, 30 mg of Fe{sub 3}O{sub 4} magnetic nanoparticles (MNPs) were added into the sample solution to collect the fine droplets of [pbmim][NTf{sub 2}]{sub 2}, physisorptively. Finally, MNPs were eluted by acetonitrile, separated by an external magnetic field and the obtained eluent was subjected to micro-sampling flame atomic absorption spectrometry (FAAS) for further analysis. Comparing with other microextraction methods, no special devices and centrifugation step are required. Parameters influencing the extraction efficiency such as extraction time, pH, concentration of chelating agent, amount of MNPs and coexisting interferences were studied. Under the optimized conditions, this method showed high extraction recovery of 93% with low LOD of 0.7 μg L{sup −1}. Good linearity was obtained in the range of 2.5–150 μg L{sup −1} with determination coefficient (r{sup 2}) of 0.9921. Relative standard deviation (RSD%) for seven repeated measurements at the concentration of 10 μg L{sup −1} was 4.1%. Finally, this method was successfully applied for determination of lead in some water and plant samples. - Highlights: • A dicationic ionic liquid was used as the extraction solvent, for the first time. • A

  18. A new approach for the determination of silicon in airborne particulate matter using electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Mukhtar, A; Limbeck, A

    2009-07-30

    In this work a new procedure for element specific analysis of silicon in airborne particulate matter is presented. The method is based on a preliminary treatment of the aerosol samples with nitric acid and perchloric acid leading to a mineralization of the organic sampling substrate, dissolution of soluble material and a homogeneous suspension of the remaining non-soluble sample fraction. ETAAS measurement of the derived slurries was performed using a Zr-treated graphite tube which prevents the formation of stable silicon carbide during sample measurement. Losses of volatile silicon species during sample pyrolysis were overcome by using Co(II) as matrix modifier and a pyrolysis temperature of only 300 degrees C. Furthermore this low pyrolysis temperature prevents charring of organic material which enables accurate ETAAS analysis. The method including the developed pretreatment procedure was evaluated using the Standard reference material 2709 (San Joaquin Soil) from NIST (National Institute of Standards and Technology, Gaithersburg, MD, USA). Suitability for measurement of Si in airborne particulate matter with an aerodynamic diameter aerosol samples and comparison of derived results with the findings obtained for the same samples after microwave digestion and subsequent ETAAS measurement. Finally the developed procedure was applied for the analysis of silicon in PM10 collected at an urban site in Vienna (Austria). Matrix matched calibration has been used for quantification of derived absorption signals. With the use of 20 microL sample injection volume for ETAAS analysis an instrumental detection limit of 52.2 microg L(-1) was obtained, which translates to method detection limits of approximately 0.52 microg m(-3) when considering the volumes of air collected per investigated aerosol sample. The reproducibility of analysis given as the relative standard deviation was 4.4% (n=12). Derived concentrations for Si in PM10 varied between 0.8 and 7.2 microg m(-3) which

  19. Speciation and determination of ultra trace amounts of inorganic tellurium in environmental water samples by dispersive liquid-liquid microextraction and electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Najafi, Nahid Mashkouri, E-mail: n-najafi@sbu.ac.ir [Department of Chemistry, Faculty of Science, Shahid Beheshti Uinversity, Evin, Tehran (Iran, Islamic Republic of); Tavakoli, Hamed; Alizadeh, Reza; Seidi, Shahram [Department of Chemistry, Faculty of Science, Shahid Beheshti Uinversity, Evin, Tehran (Iran, Islamic Republic of)

    2010-06-18

    A simple and powerful method has been developed for the rapid and selective determination of Te(IV) and Te(VI), employing dispersive liquid-liquid microextraction combined with electrothermal atomic absorption spectrometry using palladium as permanent modifier. Under acidic conditions pH 1, only Te(IV) can form a complex with ammonium pyrrolidine dithiocarbamate (APDC) and therefore be extracted into fine droplets of carbon tetrachloride (extraction solvent) which are dispersed with ethanol into the water sample solution. After centrifugation, Te(IV) was determined in the sedimented organic phase while Te(VI) remained in the aqueous phase. Total inorganic tellurium was determined after the reduction of the Te(VI) to Te(IV). Te(VI) was calculated as the difference between the measured total inorganic tellurium and Te(IV) content. The effective parameters for improving the efficiency of microextraction process were investigated by using experimental and central composite designs. Under optimal conditions the enrichment factor was 125 and the calibration graph was linear in the range of 0.015-1 ng mL{sup -1} with detection limit and characteristic mass of 0.004 ng mL{sup -1} and 0.033 pg, respectively. The relative standard deviation for 0.5 ng mL{sup -1} of tellurium measurement was 3.6% (n = 6) at ash and atomization temperature, 900 and 2600 deg. C, respectively. The recoveries of spiked Te(IV) and Te(VI) to the environmental water samples were 89.6-101.3% and 96.6-99.1%, respectively. The accuracy is also evaluated by applying the proposed method to certified reference material (NIST SRM 1643e), for which the result was in a good agreement with the certified values reported for this CRM (95% confidence level).

  20. Determination of cadmium and lead in urine samples after dispersive solid–liquid extraction on multiwalled carbon nanotubes by slurry sampling electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Álvarez Méndez, J.; Barciela García, J.; García Martín, S.; Peña Crecente, R.M.; Herrero Latorre, C., E-mail: carlos.herrero@usc.es

    2015-04-01

    A new method for the determination of Cd and Pb in urine samples has been developed. The method involves dispersive solid-phase extraction (DSPE), slurry sampling (SS), and subsequent electrothermal atomic absorption spectrometry (ETAAS). Oxidized multiwalled carbon nanotubes (MWCNTs) were used as the sorbent material. The isolated MWCNT/analyte aggregates were treated with nitric acid to form a slurry and both metals were determined directly by injecting the slurry into the ETAAS-atomizer. The parameters that influence the adsorption of the metals on MWCNTs in the DSPE process, the formation and extraction of the slurry, and the ETAAS conditions were studied by different factorial design strategies. The detection and quantification limits obtained for Cd under optimized conditions were 9.7 and 32.3 ng L{sup −1}, respectively, and for Pb these limits were 0.13 and 0.43 μg L{sup −1}. The preconcentration factors achieved were 3.9 and 5.4. The RSD values (n = 10) were less than 4.1% and 5.9% for Cd and Pb, respectively. The accuracy of the method was assessed in recovery studies, with values in the range 96–102% obtained for Cd and 97–101% for Pb. In addition, the analysis of certified reference materials gave consistent results. The DSPE–SS–ETAAS method is a novel and useful strategy for the determination of Pb and Cd at low levels in human urine samples. The method is sensitive, fast, and free of matrix interferences, and it avoids the tedious and time-consuming on-column adsorption and elution steps associated with commonly used SPE procedures. The proposed method was used to determine Cd and Pb in urine samples of unexposed healthy people and satisfactory results were obtained. - Highlights: • Cd and Pb determination based on the combination of DSP, SS and ETAAS • Urine matrix was eliminated using DSPE based on multiwalled carbon nanotubes. • Slurry sampling technique permitted the direct injection of sample into the ETAAS atomizer.

  1. Determination of total selenium in nutritional supplements and selenised yeast by Zeeman-effect graphite furnace atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Ekelund, J.

    1989-01-01

    A method for the determination of total selenium in nutritional supplements and selenised yeast is described. The samples were ashed in nitric acid. Hydrochloric acid was used to prevent precipitation of, in particular, iron salts. After appropriate dilutions, the selenium was determined by Zeeman...... the content of selenium in a selenised yeast check sample. Accuracy was assured using this sample and by recovery experiments. Between-day random error showed a coefficient of variation of 4.2%. Results from the analysis of eight different commercial supplements were in good agreement with declared contents....

  2. An atomic absorption spectrometric method for the determination of phosphorus in foodstuffs using the bismuth phosphomolybdate complex

    Directory of Open Access Journals (Sweden)

    LJILJANA V. MIHAJLOVIC

    2000-06-01

    Full Text Available A new indirect AAS method using the bismuth phosphomolybdate complex for the determination of phosphorus in foodstuffs is suggested. The bismuth phosphomolybdate complex in acid medium was extacted with isobutyl methylketone and the phosphorus was determined through bismuth in an air/acetylene flame by utilising the 223.06 nm resonance line of bismuth. The interference caused by antimony and titanium can be neglected in the presence of excess of bismuth. The detection limit of the method is 0.008 mg/mL of phosphorus.

  3. A Green Preconcentration Method for Determination of Cobalt and Lead in Fresh Surface and Waste Water Samples Prior to Flame Atomic Absorption Spectrometry

    Science.gov (United States)

    Naeemullah; Kazi, Tasneem Gul; Shah, Faheem; Afridi, Hassan Imran; Khan, Sumaira; Arian, Sadaf Sadia; Brahman, Kapil Dev

    2012-01-01

    Cloud point extraction (CPE) has been used for the preconcentration and simultaneous determination of cobalt (Co) and lead (Pb) in fresh and wastewater samples. The extraction of analytes from aqueous samples was performed in the presence of 8-hydroxyquinoline (oxine) as a chelating agent and Triton X-114 as a nonionic surfactant. Experiments were conducted to assess the effect of different chemical variables such as pH, amounts of reagents (oxine and Triton X-114), temperature, incubation time, and sample volume. After phase separation, based on the cloud point, the surfactant-rich phase was diluted with acidic ethanol prior to its analysis by the flame atomic absorption spectrometry (FAAS). The enhancement factors 70 and 50 with detection limits of 0.26 μg L−1 and 0.44 μg L−1 were obtained for Co and Pb, respectively. In order to validate the developed method, a certified reference material (SRM 1643e) was analyzed and the determined values obtained were in a good agreement with the certified values. The proposed method was applied successfully to the determination of Co and Pb in a fresh surface and waste water sample. PMID:23227429

  4. Determination of trace aluminum in biological and water samples by cloud point extraction preconcentration and graphite furnace atomic absorption spectrometry detection

    Energy Technology Data Exchange (ETDEWEB)

    Sang Hongbo [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China); Liang Pei [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)], E-mail: liangpei@mail.ccnu.edu.cn; Du Dan [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)

    2008-06-15

    A cloud point extraction (CPE) method for the preconcentration of trace aluminum prior to its determination by graphite furnace atomic absorption spectrometry (GFAAS) has been developed. The CPE method is based on the complex of Al(III) with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP), and then entrapped in non-ionic surfactant Triton X-114. PMBP was used not only as chelating reagent in CPE preconcentration, but also as chemical modifier in GFAAS determination. The main factors affecting CPE efficiency, such as pH of sample solution, concentration of PMBP and Triton X-114, equilibration temperature and time, were investigated in detail. An enrichment factor of 37 was obtained for the preconcentration of Al(III) with 10 mL solution. Under the optimal conditions, the detection limit of this method for Al(III) is 0.09 ng mL{sup -1}, and the relative standard deviation is 4.7% at 10 ng mL{sup -1} Al(III) level (n = 7). The proposed method has been applied for determination of trace amount of aluminum in biological and water samples with satisfactory results.

  5. Speciation of chromium in water samples with cloud point extraction separation and preconcentration and determination by graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Liang Pei [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)], E-mail: liangpei@mail.ccnu.edu.cn; Sang Hongbo [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)

    2008-06-15

    A novel method has been developed for the speciation of chromium in natural water samples based on cloud point extraction (CPE) separation and preconcentration, and determination by graphite furnace atomic absorption spectrometry (GFAAS). In this method, Cr(III) reacts with 1-phenyl-3-methyl-4-benzoylpyrazol-5-one (PMBP) yielding a hydrophobic complex, which then is entrapped in the surfactant-rich phase, whereas Cr(VI) remained in aqueous phase. Thus, separation of Cr(III) and Cr(VI) could be realized. Total chromium was determined after the reduction of Cr(VI) to Cr(III) by using ascorbic acid as reducing reagent. PMBP was used not only as chelating reagent in CPE procedure, but also as chemical modifier in GFAAS determination of chromium. The detection limit for Cr(III) was 21 ng L{sup -1} with an enrichment factor of 42, and the relative standard deviation was 3.5% (n = 7, c = 10 ng mL{sup -1}). The proposed method has been applied to the speciation of chromium in natural water samples with satisfactory results.

  6. Investigation of novel rapidly synergistic cloud point extraction pattern for bismuth in water and geological samples coupling with flame atomic absorption spectrometry determination

    Science.gov (United States)

    Wen, Xiaodong; Zhao, Yu; Deng, Qingwen; Ji, Shoulian; Zhao, Xia; Guo, Jie

    2012-04-01

    Rapidly synergistic cloud point extraction (RS-CPE) greatly simplified and accelerated the procedure of traditional cloud point extraction (CPE). In order to expand the application of RS-CPE, this work was carried out after the establishment of the improved extraction technique. The new established extraction method was firstly applied for bismuth extraction and determination coupled with flame atomic absorption spectrometry (FAAS) in this work. The improved RS-CPE was accomplished in the room temperature in 1 min. Non-ionic surfactant Triton X-100 (TX-100) was used as extractant. Octanol worked as cloud point revulsant and synergic reagent. TX-100 has a relatively high cloud point temperature (CPT), which limited its application in CPE. In this work, TX-100 accomplished the RS-CPE procedure in room temperature successfully. The factors influencing RS-CPE, such as concentrations of reagents, pH, conditions of phase separation, effect of environmental temperatures, salt effect and instrumental conditions, were studied systematically. Under the optimal conditions, the limit of detection (LOD) for bismuth was 4.0 μg L-1, with sensitivity enhancement factor (EF) of 43. The proposed method greatly improved the sensitivity of FAAS for the determination of bismuth and was applied to the determination of trace bismuth in real and certified samples with satisfactory analytical results. The proposed method was rapid, simple, and sensitive.

  7. Cloud Point Extraction for the Determination of Trace Amounts of Cobalt in Water and Food Samples by Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Shangzhi Wang

    2013-01-01

    Full Text Available A cloud point extraction (CPE procedure which was developed for the separation and preconcentration of trace amounts of cobalt is combined with flame atomic absorption spectrometry (FAAS to determine trace amounts of cobalt in water and food samples. The procedure is based on the formation of the hydrophobic complex between Co(II and 4-methoxy-2-sulfo-benzenediazoaminoazo-benzene (MOSDAA followed by its extraction into a Triton X-114 surfactant-rich phase. The parameters such as pH of sample, concentrations of MOSDAA and Triton X-114, equilibrium temperature, and equilibrium time, which affect both complexation and extraction, are optimized. Under the selected optimum conditions, the preconcentration of 10.0 mL, 0.1 μg mL−1 Co(II solution results in a limit of detection of 0.47 ng mL−1 (3σ and an enrichment factor of 19. A relative standard deviation of 2.78% (,  μg mL−1 for the determination of Co(II is obtained. The proposed method was applied for the determination of trace amounts of cobalt in river water and millet samples with satisfactory results.

  8. Ultra-trace determination of silver in water samples by electrothermal atomic absorption spectrometry after preconcentration with a ligand-less cloud point extraction methodology

    Energy Technology Data Exchange (ETDEWEB)

    Manzoori, Jamshid L. [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)]. E-mail: manzoori@tabrizu.ac.ir; Abdolmohammad-Zadeh, Hossein [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Amjadi, Mohammad [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2007-06-01

    A very simple and ligand-less cloud point extraction (CPE) methodology for the preconcentration of ultra-trace amounts of silver as a prior step to its determination by electrothermal atomic absorption spectrometry (ETAAS) has been developed. The method is based on the extraction of silver at pH 9 by using non-ionic surfactant polyethyleneglycolmono-p-nonylphenylether (PONPE 7.5) without adding any chelating agent. Several important variables that affect the CPE efficiency and ETAAS signal were investigated and optimized. The preconcentration of 15 ml sample solution allowed us to achieve an enhancement factor of 60. The calibration graph using the preconcentration system was linear in the range of 5-100 ng l{sup -1} with a correlation coefficient of 0.9991. The lower limit of detection (3s) obtained in the optimal conditions was 1.2 ng l{sup -1}. The relative standard deviation (R.S.D.) for eight replicate determinations at 30 ng l{sup -1} Ag level was 4.2%. The proposed method was successfully applied to the ultra-trace determination of silver in water samples.

  9. Preconcentration and determination of iron and copper in spice samples by cloud point extraction and flow injection flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, Cigdem Arpa, E-mail: carpa@hacettepe.edu.tr [Hacettepe University, Chemistry Department, 06800 Beytepe, Ankara (Turkey); Tokgoez, Ilknur; Bektas, Sema [Hacettepe University, Chemistry Department, 06800 Beytepe, Ankara (Turkey)

    2010-09-15

    A flow injection (FI) cloud point extraction (CPE) method for the determination of iron and copper by flame atomic absorption spectrometer (FAAS) has been improved. The analytes were complexed with 3-amino-7-dimethylamino-2-methylphenazine (Neutral Red, NR) and octylphenoxypolyethoxyethanol (Triton X-114) was added as a surfactant. The micellar solution was heated above 50 {sup o}C and loaded through a column packed with cotton for phase separation. Then the surfactant-rich phase was eluted using 0.05 mol L{sup -1} H{sub 2}SO{sub 4} and the analytes were determined by FAAS. Chemical and flow variables influencing the instrumental and extraction conditions were optimized. Under optimized conditions for 25 mL of preconcentrated solution, the enrichment factors were 98 and 69, the limits of detection (3s) were 0.7 and 0.3 ng mL{sup -1}, the limits of quantification (10s) were 2.2 and 1.0 ng mL{sup -1} for iron and copper, respectively. The relative standard deviation (RSD) for ten replicate measurements of 10 ng mL{sup -1} iron and copper were 2.1% and 1.8%, respectively. The proposed method was successfully applied to determination of iron and copper in spice samples.

  10. Column preconcentration of gold by adsorbing AuCl4- onto methyltrioctyl ammonium chloride-naphthalene and subsequent atomic absorption spectrometric determination.

    Science.gov (United States)

    Behpour, M; Attaran, A M; Ghoreishi, S M; Soltani, N

    2005-05-01

    A sensitive, selective and simple preconcentration method for ultra-trace gold determination has been developed that uses naphthalene-methyltrioctyl ammonium chloride (Aliquat 336s) as an adsorbent. Gold, in the form of AuCl4-, was retained by the adsorbent in the column at a flow rate of 1 ml min(-1). After filtration, the solid mass consisting of the gold complex and naphthalene was dissolved out of the column with 5 ml of N,N-dimethylformamide (DMF), and the metal was then determined by atomic absorption spectrometry. In the initial solution, the calibration graph of absorbance versus gold concentration was found to be linear in the range 0.5-150 ng ml(-1) Au(III) with r=0.997 (n=9), and the 3 s detection limit was 0.428 ng ml(-1). The relative standard deviation for eight replicate measurements of 20 microg of gold was 2.14%. Preconcentration factors of 390 and 650 were achieved using 5 ml and 3 ml of DMF, respectively. The proposed method was successfully applied to the determination of gold in wastewater, processed pool water, slurry pool water, and raw well-water from the Moteh gold mine, and synthetic samples.

  11. Simultaneous speciation and preconcentration of ultra traces of inorganic tellurium and selenium in environmental samples by hollow fiber liquid phase microextraction prior to electrothermal atomic absorption spectroscopy determination.

    Science.gov (United States)

    Ghasemi, Ensieh; Najafi, Nahid Mashkouri; Raofie, Farhad; Ghassempour, Alireza

    2010-09-15

    A simple and effective speciation and preconcentration method based on hollow fiber liquid phase microextraction (HF-LPME) was developed for simultaneous separation of trace inorganic tellurium and selenium in environmental samples prior to electrothermal atomic absorption spectroscopy (ETAAS) determination. The method involves the selective extraction of the Te (IV) and Se (IV) species by HF-LPME with the use of ammonium pyrrolidinecarbodithioate (APDC) as the chelating agent. The complex compounds were extracted into 10 microL of toluene and the solutions were injected into a graphite furnace for the determination of Te (IV) and Se (IV). To determine the total tellurium and selenium in the samples, first Te (VI) and Se (VI) were reduced to Te (IV) and Se (IV), and then the microextraction method was performed. The experimental parameters of HF-LPME were optimized using a central composite design after a 2(n-1) fractional factorial experimental design. Under optimum conditions, enrichment factors of up to 520 and 480 were achieved for Te (IV) and Se (IV), respectively. The detection limits were 4 ng L(-1) with 3.5% RSD (n=5, c=2.0 microg L(-1)) for Te (IV) and 5 ng L(-1) with 3.1% RSD for Se (IV). The applicability of the developed technique was evaluated by application to spiked, environmental water and soil samples.

  12. Rapid and simultaneous determination of essential minerals and trace elements in human milk by improved flame atomic absorption spectroscopy (FAAS) with microwave digestion.

    Science.gov (United States)

    Luo, Yang; Zhang, Bo; Chen, Ming; Wang, Jue; Zhang, Xue; Gao, Wei-Yin; Huang, Jun-Fu; Fu, Wei-Ling

    2010-09-08

    A method for the simultaneous and economical determination of many trace elements in human milk is developed. Two multi-element hollow cathode lamps (HCLs) were used instead of single-element HCLs to improve the sample throughput of flame atomic absorption spectroscopy (FAAS). The microwave digestion of milk is optimized prior to detection, and the performance characteristics of the improved analysis method are identified. Clinical samples are detected by both FAAS and inductively coupled plasma-optical emission spectroscopy (ICP-OES) for methodology evaluation. Results reveal that the proposed FAAS with multi-element HCLs could determine six essential minerals and trace elements within 15 min. This method provides a linear analytical range of 0.01-10 mg L(-1). For Ca, Cu, Fe, Mg, Mn, and Zn, the limits of determination are 1.5, 3, 1.8, 2.2, 2.1, and 1.3 microg L(-1), respectively. The mean relative standard deviations (RSDs) of intra- and interassays are lower than 7%. Excellent operational characteristics of rapidity, simplicity, and economy make the proposed method a promising one for the quantification of trace elements in human milk in clinics of underdeveloped areas.

  13. Optimization of dispersive liquid-liquid microextraction for the selective determination of trace amounts of palladium by flame atomic absorption spectroscopy.

    Science.gov (United States)

    Kokya, Taher Ahmadzadeh; Farhadi, Khalil

    2009-09-30

    A new simple and reliable method for rapid and selective extraction and determination of the trace levels of Pd(2+) ion was developed by dispersive liquid-liquid microextraction preconcentration and flame atomic absorption spectrometry detection. In the proposed approach, thioridazine HCl (TRH) was used as a Pd(2+) ion selective complexing agent. The effective parameters on the extraction recovery were studied and optimized utilizing two decent optimization methods; factorial design and central composite design (CCD). Through factorial design the best efficiency of extraction acquired using ethanol and chloroform as dispersive and extraction solvents respectively. CCD optimization resulted in 1.50 mL of dispersive solvent; 0.15 mL of extraction solvent; 0.45 mg of TRH and 250 mg of potassium chloride salt per 5 mL of sample solution. Under the optimum conditions the calibration graph was linear over the range 100-2000 microgL(-1). The average relative standard deviation was 0.7% for five repeated determinations. The limit of detection was 90 microg L(-1). The average enrichment factor and recovery reached 45.7% and 74.2% respectively. The method was successfully applied to the determination of trace amounts of palladium in the real water samples.

  14. Application of l-cystine modified zeolite for preconcentration and determination of ultra-trace levels of cadmium by flame atomic absorption spectrometry.

    Science.gov (United States)

    Rezvani, Seyyed Ahmad; Soleymanpour, Ahmad

    2016-03-04

    A very convenient, sensitive and precise solid phase extraction (SPE) system was developed for enrichment and determination of ultra-trace of cadmium ion in water and plant samples. This method was based on the retention of cadmium(II) ions by l-cystine adsorbed in Y-zeolite and carry out in a packed mini-column. The retained cadmium ions then were eluted and determined by flame atomic absorption spectrometry. The scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) spectroscopy techniques were applied for the characterization of cystine modified zeolite (CMZ). Some experimental conditions affecting the analytical performance such as pH, eluent type, concentration of sample, eluent flow rate and also the presence of interfering ions were investigated. The calibration graph was linear within the range of 0.1-7.5ngmL(-1) and limit of detection was obtained 0.04ngmL(-1) with the preconcentration factor of 400. The relative standard deviation (RSD) was obtained 1.4%, indicating the excellent reproducibility of this method. The proposed method was successfully applied for the extraction and determination of cadmium(II) ion in black tea, cigarette's tobacco and also various water samples.

  15. Separation and determination of copper in bottled water samples by combination of dispersive liquid--liquid microextraction and microsample introduction flame atomic absorption spectrometry.

    Science.gov (United States)

    Citak, Demirhan; Tuzen, Mustafa

    2013-01-01

    A new and simple method for the determination of trace amounts of Cu(II) was developed by combination of dispersive liquid-liquid microextraction (DLLME) preconcentration and microsample introduction flame atomic absorption spectrometry. In this method, ethanol and chloroform were chosen as disperser and extraction solvents, respectively, and 1-nitroso-2-naphthol was used as the complexing agent. The factors affecting the extraction efficiency and determination of Cu(II), including extraction and disperser solvent nature and volume, concentration of the complexing agent, pH of the solution, extraction time, and matrix ions, were investigated. Under optimal conditions, the LOD for Cu(II) was 0.95 microg/L with a preconcentration factor of 70. The RSD was 1.9%. The accuracy of the developed DLLME method was verified by determination of Cu(II) in a certified reference material (NRCC-SLRS-4 river water). The relative error was -3.31%. The developed preconcentration procedure was successfully applied to the analysis of bottled drinking water samples.

  16. Ligandless cloud point extraction of trace amounts of palladium and rhodium in road dust samples using Span 80 prior to their determination by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Mahmoud Roushani

    2014-01-01

    Full Text Available In this study, a procedure is developed for cloud point extraction of Pd(II and Rh(III ions in aqueous solution using Span 80 (non-ionic surfactant prior to their determination by flame atomic absorption spectroscopy. This method is based on the extraction of Pd(II and Rh(III ions at a pH of 10 using Span 80 with no chelating agent. We investigated the effect of various parameters on the recovery of the analyte ions, including pH, equilibration temperature and time, concentration of Span 80, and ionic strength. Under the best experimental conditions, the limits of detection based on 3Sb for Pd(II and Rh(III ions were 1.3 and 1.2 ng mL-1, respectively. Seven replicate determinations of a mixture of 0.5 µg mL-1 palladium and rhodium ions gave a mean absorbance of 0.058 and 0.053 with relative standard deviations of 1.8 and 1.6%, respectively. The developed method was successfully applied to the extraction and determination of the palladium and rhodium ions in road dust and standard samples and satisfactory results were obtained.

  17. Feasibility of dispersive liquid-liquid microextraction for extraction and preconcentration of Cu and Fe in red and white wine and determination by flame atomic absorption spectrometry

    Science.gov (United States)

    Seeger, Tassia S.; Rosa, Francisco C.; Bizzi, Cezar A.; Dressler, Valderi L.; Flores, Erico M. M.; Duarte, Fabio A.

    2015-03-01

    A method for extraction and preconcentration of Cu and Fe in red and white wines using dispersive liquid-liquid microextraction (DLLME) and determination by flame atomic absorption spectrometry (F AAS) was developed. Extraction was performed using sodium diethyldithiocarbamate as chelating agent and a mixture of 40 μL of 1,2-dichlorobenzene (extraction solvent) and 900 μL of methanol (dispersive solvent). Some parameters that influencing the extraction efficiency such as pH (2 to 5), concentration of chelating agent (0 to 2%), effect of salt addition (0 to 10%), number of washing steps (1 to 4) and centrifugation time (0 to 15 min) were studied. Accuracy was evaluated after microwave-assisted digestion in closed vessels and analytes were determined by inductively coupled plasma optical emission spectrometry. Agreement with the proposed method ranged from 91 to 110 and from 89 to 113% for Cu and Fe, respectively. Calibration of F AAS instrument was performed using analyte addition method and limits of detection were 6.3 and 2.4 μg L- 1 for Cu and Fe, respectively. The proposed method was applied for the determination of Cu and Fe in five samples of red wine and three samples of white wine, with concentration ranging from 21 to 178 μg L- 1 and from 1.38 to 3.74 mg L- 1, respectively.

  18. A novel ionic liquid/micro-volume back extraction procedure combined with flame atomic absorption spectrometry for determination of trace nickel in samples of nutritional interest

    Energy Technology Data Exchange (ETDEWEB)

    Dadfarnia, Shayesteh, E-mail: sdadfarnia@yazduni.ac.ir [Department of Chemistry, Faculty of Science, Yazd University, 89195/74, Yazd (Iran, Islamic Republic of); Haji Shabani, Ali Mohammad; Shirani Bidabadi, Mahboubeh; Jafari, Abbas Ali [Department of Chemistry, Faculty of Science, Yazd University, 89195/74, Yazd (Iran, Islamic Republic of)

    2010-01-15

    A simple, highly sensitive and environment-friendly method for the determination of trace amount of nickel ion in different matrices is proposed. In the preconcentration step, the nickel from 10 mL of an aqueous solution was extracted into 500 {mu}L of ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate [C{sub 4}MIM][PF{sub 6}], containing PAN as complexing agent. Subsequently, the PAN complex was back-extracted into 250 {mu}L of nitric acid solution, and 100 {mu}L of it was analyzed by flow injection flame atomic absorption spectrometry (FI-FAAS). The main parameter influencing the extraction and determination of nickel, such as pH, concentration of PAN, extraction time and temperature, ionic strength, and concentration of stripping acid solution, were optimized. An enhancement factor of 40.2 was achieved with 25 mL sample. The limit of detection (LOD) and quantification obtained under the optimum conditions were 12.5 and 41.0 {mu}g L{sup -1}, respectively. To validate the proposed methods two certified reference materials 681-I and BCR No. 288 were analyzed and the results were in good agreement with the certified values. The proposed method was successfully applied to determination of nickel in water samples, rice flour and black tea.

  19. A novel ionic liquid/micro-volume back extraction procedure combined with flame atomic absorption spectrometry for determination of trace nickel in samples of nutritional interest.

    Science.gov (United States)

    Dadfarnia, Shayesteh; Shabani, Ali Mohammad Haji; Bidabadi, Mahboubeh Shirani; Jafari, Abbas Ali

    2010-01-15

    A simple, highly sensitive and environment-friendly method for the determination of trace amount of nickel ion in different matrices is proposed. In the preconcentration step, the nickel from 10 mL of an aqueous solution was extracted into 500 microL of ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate [C(4)MIM][PF(6)], containing PAN as complexing agent. Subsequently, the PAN complex was back-extracted into 250 microL of nitric acid solution, and 100 microL of it was analyzed by flow injection flame atomic absorption spectrometry (FI-FAAS). The main parameter influencing the extraction and determination of nickel, such as pH, concentration of PAN, extraction time and temperature, ionic strength, and concentration of stripping acid solution, were optimized. An enhancement factor of 40.2 was achieved with 25 mL sample. The limit of detection (LOD) and quantification obtained under the optimum conditions were 12.5 and 41.0 microg L(-1), respectively. To validate the proposed methods two certified reference materials 681-I and BCR No. 288 were analyzed and the results were in good agreement with the certified values. The proposed method was successfully applied to determination of nickel in water samples, rice flour and black tea.

  20. Speciation and determination of inorganic mercury and methylmercury by headspace single drop microextraction and electrothermal atomic absorption spectrometry in water and fish

    Energy Technology Data Exchange (ETDEWEB)

    Sarica, Deniz Yurtsever [Scientific and Technological Research Council of Turkey, Ankara Test and Analysis Laboratory, TUeBITAK/ATAL, Besevler, Ankara (Turkey); Tuerker, Ali Rehber [Science Faculty, Department of Chemistry, Gazi University, Ankara (Turkey)

    2012-05-15

    In this study, headspace single drop microextraction (HS-SDME) method in combination with electrothermal atomic absorption spectrometry (ETAAS) method was developed and validated for the speciation and determination of inorganic mercury (iHg) and methylmercury (MeHg). MeHg and iHg species were reduced to volatile methylmercury hydride (CH{sub 3}HgH) and elemental mercury, respectively, in the presence of NaBH{sub 4} and trapped onto a drop of acceptor phase in the tip of a microsyringe. Thiourea and ammonium pyrrolydinedithiocarbamate (APDC) were tested as the acceptor phase. The experimental parameters of the method such as microextraction time, temperature, NaBH{sub 4} concentration, acceptor phase concentration, and pH of the medium were investigated to obtain distinctive conditions for mercury species. Possible interference effects have also been investigated. In order to validation of the method, analytical figures of merits such as accuracy, precision, limit of detection (LOD), limit of quantitation (LOQ), and linear working range have been evaluated. Accuracy of the method has been verified by analyzing certified reference materials (BCR 453 Tuna fish) and spiked samples. The proposed method was applied for the speciation and determination of mercury species in water and fish samples. Mercury species (MeHg and iHg) have been determined in the real samples with a relative error less than 10%. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. A Green Preconcentration Method for Determination of Cobalt and Lead in Fresh Surface and Waste Water Samples Prior to Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Naeemullah

    2012-01-01

    Full Text Available Cloud point extraction (CPE has been used for the preconcentration and simultaneous determination of cobalt (Co and lead (Pb in fresh and wastewater samples. The extraction of analytes from aqueous samples was performed in the presence of 8-hydroxyquinoline (oxine as a chelating agent and Triton X-114 as a nonionic surfactant. Experiments were conducted to assess the effect of different chemical variables such as pH, amounts of reagents (oxine and Triton X-114, temperature, incubation time, and sample volume. After phase separation, based on the cloud point, the surfactant-rich phase was diluted with acidic ethanol prior to its analysis by the flame atomic absorption spectrometry (FAAS. The enhancement factors 70 and 50 with detection limits of 0.26 μg L−1 and 0.44 μg L−1 were obtained for Co and Pb, respectively. In order to validate the developed method, a certified reference material (SRM 1643e was analyzed and the determined values obtained were in a good agreement with the certified values. The proposed method was applied successfully to the determination of Co and Pb in a fresh surface and waste water sample.

  2. Investigation of novel rapidly synergistic cloud point extraction pattern for bismuth in water and geological samples coupling with flame atomic absorption spectrometry determination.

    Science.gov (United States)

    Wen, Xiaodong; Zhao, Yu; Deng, Qingwen; Ji, Shoulian; Zhao, Xia; Guo, Jie

    2012-04-01

    Rapidly synergistic cloud point extraction (RS-CPE) greatly simplified and accelerated the procedure of traditional cloud point extraction (CPE). In order to expand the application of RS-CPE, this work was carried out after the establishment of the improved extraction technique. The new established extraction method was firstly applied for bismuth extraction and determination coupled with flame atomic absorption spectrometry (FAAS) in this work. The improved RS-CPE was accomplished in the room temperature in 1 min. Non-ionic surfactant Triton X-100 (TX-100) was used as extractant. Octanol worked as cloud point revulsant and synergic reagent. TX-100 has a relatively high cloud point temperature (CPT), which limited its application in CPE. In this work, TX-100 accomplished the RS-CPE procedure in room temperature successfully. The factors influencing RS-CPE, such as concentrations of reagents, pH, conditions of phase separation, effect of environmental temperatures, salt effect and instrumental conditions, were studied systematically. Under the optimal conditions, the limit of detection (LOD) for bismuth was 4.0 μg L(-1), with sensitivity enhancement factor (EF) of 43. The proposed method greatly improved the sensitivity of FAAS for the determination of bismuth and was applied to the determination of trace bismuth in real and certified samples with satisfactory analytical results. The proposed method was rapid, simple, and sensitive.

  3. Preconcentration and determination of copper and cadmium ions with 1,6-bis(2-carboxy aldehyde phenoxy)butane functionalized Amberlite XAD-16 by flame atomic absorption spectrometry.

    Science.gov (United States)

    Oral, Elif V; Dolak, Ibrahim; Temel, Hamdi; Ziyadanogullari, Berrin

    2011-02-15

    A new chelating resin, covalently linked 1,6-bis(2-carboxy aldehyde phenoxy)butane with the Amberlite XAD-16 was synthesized and used for preconcentration of Cu(II) and Cd(II) prior to their determination by flame atomic absorption spectrometry (FAAS). It was characterized by elemental analyses and Fourier Transform Infrared Spectroscopy (FT-IR). Cu(II) and Cd(II) ions were quantitatively preconcentrated on minicolumn loaded with synthesised resin at pH 4.00 and 6.00, respectively. They were eluated with 5 mL of 0.5 mol L(-1) HCl. Recoveries of Cu(II) and Cd(II) were found to be 100±2.15, 100±1.40 (N=5), the limits of detection of Cu(II) and Cd(II) in the determination by FAAS (3s, N=20) were found to be 0.33 and 1.19 μg L(-1), respectively. The effect of foreign ions on the recovery has been investigated. The proposed method has been applied for the determination of Cu(II) and Cd(II) ions to the real samples collected from Tigris river water in Diyarbakir and Elaziğ cities in Turkey. Standard addition method and analysis of the certified reference material (NCS-DC 73350) was employed to check the accuracy of the method.

  4. Imidazole-Modified Nanoporous Silica for Lead Ion Solid Phase Extraction Prior to Determination from Industrial Wastewaters by Flame Atomic Absorption Spectrometry.

    Science.gov (United States)

    Behbahani, Ali; Ardjmand, Mehdi

    2015-01-01

    A new method was applied to produce modified nanoporous silica as a novel sorbent for Pb(II) ion SPE from industrial wastewater samples. In this modified method, the produced nanoporous silica has a higher functional group loading, which leads to a higher preconcentration factor as well as a lower LOD. This modified nanoporous silica was used for preconcentration prior to subsequent determination of Pb(II) ions by flame atomic absorption spectrometry. Various parameters such as the eluent, pH of the sample solution, and flow rate were optimized during this work. Also, the effect of a variety of ions on preconcentration and recovery of Pb(II) ions was investigated. The LOD, defined as five times the SD of the blank, was determined to be lower than 0.1 mg/L with an RSD of <2%. The accuracy of the method was established by analyzing standard reference materials with certified Pb concentrations. Finally, the established method was successfully applied for determination of the Pb(II) ion concentration in industrial wastewater samples.

  5. Investigation of spectral interferences in the determination of lead in fertilizers and limestone samples using high-resolution continuum source graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Aline R. [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciência e Tecnologia do CNPq — INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Becker, Emilene M.; François, Luciane L.; Jesus, Alexandre de [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Vale, Maria Goreti R. [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciência e Tecnologia do CNPq — INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Welz, Bernhard [Instituto Nacional de Ciência e Tecnologia do CNPq — INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Departamento de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Dessuy, Morgana B., E-mail: mbdessuy@ufrgs.br [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Andrade, Jailson B. de [Instituto Nacional de Ciência e Tecnologia do CNPq — INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil)

    2014-11-01

    In the present work, spectral interferences on the determination of lead in fertilizer and limestone samples were investigated using high-resolution continuum source graphite furnace atomic absorption spectrometry at the main analytical lines: 217.001 and 283.306 nm. For these investigations, samples were introduced into the furnace as slurry together with a mixture of Pd and Mg as chemical modifier. Spectral interferences were observed for some samples at both analytical lines. In order to verify whether a wet digestion procedure would avoid these interferences, a reference method for wet digestion of fertilizers was employed as an alternative sample preparation procedure. However, the same interferences were also observed in the digested samples. In order to identify and eliminate the fine-structured background using a least-squares background correction, reference spectra were generated using the combination of different species. The use of the latter technique allowed the elimination of spectral interferences for most of the investigated samples, making possible the determination of lead in fertilizer and limestone samples free of interferences. The best results were found using a reference spectrum of NH{sub 4}H{sub 2}PO{sub 4} at 217.001 nm, and a mixture of H{sub 2}SO{sub 4} + Ca and HNO{sub 3} + Ca at the 283.306 nm line. The accuracy of the method was evaluated using a certified reference material “Trace Elements in Multi-Nutrient Fertilizer”. Similar results were obtained using line source graphite furnace atomic absorption spectrometry with Zeeman-effect background correction, indicating that the latter technique was also capable to correct the spectral interferences, at least in part. - Highlights: • Spectral interferences on the determination of lead in fertilizers and limestone. • The analytical lines at 217.001 nm and 283.306 nm using HR-CS GF AAS. • Various combinations of compounds were used to create reference spectra. • LSBC

  6. Determination of the in vivo pharmacokinetics of palladium-bacteriopheophorbide (WST09) in EMT6 tumour-bearing Balb/c mice using graphite furnace atomic absorption spectroscopy.

    Science.gov (United States)

    Brun, Pierre Hervé; DeGroot, Jennifer L; Dickson, Eva F Gudgin; Farahani, Mohsen; Pottier, Roy H

    2004-01-01

    Palladium-bacteriopheophorbide (WST09), a novel bacteriochlorophyll derivative, is currently being investigated for use as a photodynamic therapy (PDT) drug due to its strong absorption in the near-infrared region and its ability to efficiently generate singlet oxygen when irradiated. In this study, we determined the pharmacokinetics and tissue distribution of WST09 in female EMT6 tumour-bearing Balb/c mice in order to determine if selective accumulation of this drug occurs in tumour tissue. A total of 41 mice were administered WST09 by bolus injection into the tail vein at a dose level of 5.0 +/- 0.8 mg kg(-1). Three to six mice were sacrificed at each of 0.08, 0.25, 0.5, 1.0, 3.0, 6.0, 9.0, 12, 24, 48, 72, and 96 h post injection, and an additional three control mice were sacrificed without having been administered WST09. Terminal blood samples as well as liver, skin, muscle, kidney and tumour samples were obtained from each mouse and analyzed for palladium content (from WST09) using graphite furnace atomic absorption spectroscopy (GFAAS). The representative concentration of WST09 in the plasma and tissues was then calculated. Biphasic kinetics were observed in the plasma, kidney, and liver with clearance from each of these tissues being relatively rapid. Skin, muscle and tumour did not show any significant accumulation at all time points investigated. No selective drug accumulation was seen in the tumour and normal tissues, relative to plasma. Thus the results of this study indicate that vascular targeting resulting from WST09 in the circulation, as opposed to selective WST09 accumulation in tumour tissues, may be responsible for PDT effects in tumours that have been observed in other WST09 studies.

  7. Electrochemical generation of arsenic volatile species using a gold/mercury amalgam cathode. Determination of arsenic by atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Andrea Caiminagua

    2015-03-01

    Full Text Available The electrochemical generation of arsenic volatile species (arsine using an Au/Hg amalgam cathode in a 0.5 M H2SO4 solution, is described. Results were compared with those obtained with other cathodes commonly used for generation of arsine. The effects of the electrolytic conditions and interferent ions have been studied. Results show that the Au/Hg cathode has better tolerance to interference and higher repeatability than cathodes made out of platinum (Pt, gold (Au, reticulated glassy carbon (RGC, lead (Pb. Under optimized conditions, a 0.027 μg L−1 (3σ detection limit for As(III in aqueous solutions and a 2.4% relative standard deviation for a 0.1 μg L−1 As(III were obtained. The accuracy of the method was verified by determination of As in a certified reference material. The proposed method was applied to the determination of As in spiked tap water samples.

  8. Iridium as permanent modifier in the determination of lead in whole blood and urine by electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Grinberg, Patricia; de Campos, Reinaldo Calixto

    2001-10-01

    The behavior of Iridium as a thermally deposited permanent modifier for the determination of lead by GFAAS was studied. The iridium coating procedure was optimized using a two-level factorial design. Using the optimized coating procedure, up to 1100 firings were possible with the same coating without sensitivity losses. The system was used in the determination of lead in whole blood and urine. A mixture of 0.1% Triton X-100 and 0.2% nitric acid was used as diluent. Pyrolysis temperature was 800°C for both matrices. Spiked, low-level samples were used for calibration. Under these conditions, no significant difference was found in comparison to the results obtained using a validated conventional modification procedure employing phosphate as modifier. Also, good agreement between found and certified/reference values were observed in the analysis of certified and commercial quality control materials, respectively. Such agreement was observed even using a 1100 times fired Ir coated platform-graphite tube assembly.

  9. Solvent bar micro-extraction with graphite atomic absorption spectrometry for the determination of silver in ocean water.

    Science.gov (United States)

    López-López, José A; Herce-Sesa, Belén; Moreno, Carlos

    2016-10-01

    Main drawbacks for silver determination in seawater are the effects of samples matrix and that Ag appears in the sub ng L(-1). Available methods for sample preparation in Ag analysis are based on solid and liquid extraction using tedious process that increase the cost of analysis and the risk of sample contamination, producing important waste amounts. Solvent bar micro-extraction (SBME) allows the pre-concentration of Ag in a micro-volume of the ionic liquid Aliquat 336® in kerosene solution. For this reason, it is considered as a green alternative to standard methods. The method has been optimized using synthetic seawater samples, offering the highest response for samples at pH=2, using 5% Aliquat 336® dissolved in kerosene containing 5% dodecan-1-ol as acceptor solution and after 1h stirring at 800rpm. The method exhibited linearity up to 50ngL(-1), with a limit of detection of 0.09ngL(-1), covering the concentration range of interest for environmental studies. Finally, it was applied for determination of Ag in real seawater samples, and the results were compared with the reference method of liquid-liquid extraction with 1-pyrrolidine-dithiocarbamate and diethylammonium-diethyldithiocarbamate, showing the applicability of ionic liquid based SBME using Aliquat 336(®) for the simple monitoring of silver ultra-traces in seawater analysis.

  10. Preconcentration and Determination of Trace Amounts of Heavy Metals in Water Samples Using Membrane Disk and Flame Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    ALI,Moghimi

    2007-01-01

    A fast and simple method for preconcentration of Ni2+, Cd2+, Pb2+, Zn2+, Cu2+ and Co2+ from natural water samples was developed. The metal ions were complexed with sodium diethyldithiocarbamate (Na-DDTC), then adsorbed onto octadecyl silica membrane disk, recovered and determined by FAAS. Extraction efficiency, influence of sample volume and eluent flow rates, effects of pH, amount of Na-DDTC, nature and amount of eluent for elution of metal ions from membrane disk, break through volume and limit of detection have been evaluated. The effect of foreign ions on the percent recovery of heavy metal ions has also been studied. The limit of detection of the proposed method for Ni2+, Cd2+, Pb2+, Zn2+, Cu2+ and Co2+was found to be 2.03, 0.47, 3.13, 0.44, 1.24 and 2.05ng·mL-1, respectively. The proposed (DDTC) method has been successfully applied to the recovery and determination of heavy metal ions in different water samples.

  11. Dithiocarbamate functionalized or surface sorbed Merrifield resin beads as column materials for on line flow injection-flame atomic absorption spectrometry determination of lead.

    Science.gov (United States)

    Praveen, R S; Naidu, G R K; Prasada Rao, T

    2007-09-26

    This article describes the preparation of dithiocarbamate immobilized/functionalized and diethylammonium dithiocarbamate (DDTC) sorbed Merrifield Chloromethylated Resin (MCR) beads and comparison of these materials for on-line flow injection (FI)-flame atomic absorption spectrometry (FAAS) determination of lead. The above two materials enrich lead quantitatively over an identical optimal pH range (8.0-9.0), a preconcentration/loading time (up to 4 min) and elution with acidified methanol (a minimum of 0.01 molL(-1) HNO(3) in methanol). However, the detection limit for lead using dithiocarbamate functionalized MCR beads is 1.3 microgL(-1) compared to 3 microgL(-1) for DDTC sorbed MCR beads. Again, the sensitivity enhancement over direct FAAS signal is 48- and 27-fold, respectively. In addition, dithiocarbamate functionalized MCR beads offers better precision compared to DDTC sorbed MCR beads as the corresponding relative standard deviation (R.S.D.) values for five successive determinations of 0.20 microgmL(-1) are 1.44 and 4.36%, respectively. The accuracy of the developed on-line FI-FAAS procedure employing dithiocarbamate functionalized MCR beads as column material was tested by analyzing Certified Reference Material (CRM) of soil (IAEA soil-7) and marine sediment reference material (MESS-3) supplied by International Atomic Energy Agency (IAEA), Vienna and National Research Council (NRC), Canada, respectively. Furthermore, the developed procedure has been successfully tested for the analysis of surface, pond, ground and effluent water and soil samples collected from the vicinity of lead acid battery industry in India.

  12. 原子吸收法测定猪全血中的硒%Determination of Selenium in Pig Blood by Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    梁敏仪; 王小军; 冯才敏

    2015-01-01

    研究了石墨炉原子吸收法测硒的工作条件,采用标准加入法进行基体匹配,氯化钯作为基体改进剂提高灰化温度,氘灯系统扣除背景干扰。试验结果表明,采用氯化钯为基体改进剂,灰化和原子化温度分别为1200℃和2400℃时,方法检出限为0.13 ng/mL,线性范围1.3~50 ng/mL,方法回收率高于85%,该方法灵敏度高,操作简便快捷,可用于测定全血中的硒。%This paper carried out an experiment on the working conditions of graphite furnace atomic absorption spec-trometry to determine selenium. In the experiment, pig whole blood was added by using standard addition method to match the matrix, palladium chloride was used as a matrix modifier to raise the ashing temperature, and deuterium lamp was used as background correction system. The experiment shows that the optimized ashing temperature and atomization temperature is 1 200 DEG and 2 400 DEG C respectively on condition of using the matrix modifier palladium chloride, detection limit and linear range is 0.13 ng/mL and 1.3~50 ng/mL respectively, and recovery rate is greater than 85%. The method is highly sensitive, simple and efficient for the determination of selenium in whole blood.

  13. Cloud point extraction-atomic absorption spectrometry for pre-concentration and determination of cadmium in cigarette samples.

    Science.gov (United States)

    Tavallali, Hossein; Boustani, Fazlollah; Yazdandoust, Mozhdeh; Aalaei, Mehdi; Tabandeh, Mahboobeh

    2013-05-01

    A new complexing agent, 2-((2-((1H-benzo[d]imidazole-2yl)methoxy)phenoxy)methyl)-1H-benzo[d]imidazole (BIMPI), was used in cloud point extraction and applied for selective pre-concentration of trace amounts of cadmium in cigarette samples. Cadmium was complexed with BIMPI in a buffer solution (pH = 10) using Triton X-114 as surfactant and quantitatively extracted into a small volume of the surfactant-rich phase after centrifugation. Under optimized conditions (pH = 10.0, 0.8 × 10(-4) mol L(-1) BIMPI and 0.08 % (w/v) Triton X-114), calibration graph was linear in the range of 34.0-1,670.0 μg L(-1). The proposed method was applied to the determination of Cd in various cigarette (tobacco) samples which gave satisfactory results.

  14. Simultaneous preconcentration of cadmium and chromium(III) in water samples by cloud point extraction and their determination by flame atomic absorption spectrometry.

    Science.gov (United States)

    Meng, Lifen; Ning, Jinyan; Yang, Yaling

    2014-01-01

    A sensitive and simple method for flame atomic absorption spectrometry determination of traces of cadmium and chromium(III) species in water samples after preconcentration by cloud point extraction has been developed. A novel complex agent of alizarin complexone with cadmium (Cd) and chromium (Cr(III)) was quantitatively extracted in surface primary alcohol ethoxylate-rich phase at 33 °C. The effects of experimental conditions including pH of sample solution, concentration of chelating agent and salt, equilibration temperature and time, and foreign ions were evaluated in order to enhance sensitivity of the method. Under optimal conditions, the low limit detections were 6.7 and 3.2 μg/L, and the enrichment factors were 24 and 20 for Cd and Cr(III), respectively. The relative standard deviations were 3.8 and 2.5% for Cd and Cr(II), respectively (n = 11). The high recoveries of the spiked Cd and Cr(III) ions were obtained in the range of 90-116%. The proposed method has been successfully applied for the determination of Cd and Cr(III) in water samples.

  15. A new cloud point extraction procedure for determination of inorganic antimony species in beverages and biological samples by flame atomic absorption spectrometry.

    Science.gov (United States)

    Altunay, Nail; Gürkan, Ramazan

    2015-05-15

    A new cloud-point extraction (CPE) for the determination of antimony species in biological and beverages samples has been established with flame atomic absorption spectrometry (FAAS). The method is based on the fact that formation of the competitive ion-pairing complex of Sb(III) and Sb(V) with Victoria Pure Blue BO (VPB(+)) at pH 10. The antimony species were individually detected by FAAS. Under the optimized conditions, the calibration range for Sb(V) is 1-250 μg L(-1) with a detection limit of 0.25 μg L(-1) and sensitive enhancement factor of 76.3 while the calibration range for Sb(III) is 10-400 μg L(-1) with a detection limit of 5.15 μg L(-1) and sensitive enhancement factor of 48.3. The precision as a relative standard deviation is in range of 0.24-2.35%. The method was successfully applied to the speciative determination of antimony species in the samples. The validation was verified by analysis of certified reference materials (CRMs).

  16. Cloud point extraction for the determination of lead and cadmium in urine by graphite furnace atomic absorption spectrometry with multivariate optimization using Box-Behnken design

    Energy Technology Data Exchange (ETDEWEB)

    Maranhao, Tatiane de A; Martendal, Edmar; Borges, Daniel L.G.; Carasek, Eduardo [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Welz, Bernhard [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Grupo de Pesquisa em Quimica Analitica, Instituto de Quimica, Universidade Federal da Bahia, 40170-290, Salvador, BA (Brazil); Curtius, Adilson J. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)], E-mail: curtius@qmc.ufsc.br

    2007-09-15

    Cloud point extraction (CPE) is proposed as a pre-concentration procedure for the determination of Pb and Cd in undigested urine by graphite furnace atomic absorption spectrometry (GF AAS). Aliquots of 0.5 mL urine were acidified with HCl and the chelating agent ammonium O,O-diethyl dithiophosphate (DDTP) was added along with the non-ionic surfactant Triton X-114 at the optimized concentrations. Phase separation was achieved by heating the mixture to 50 deg. C for 15 min. The surfactant-rich phase was analyzed by GF AAS, employing the optimized pyrolysis temperatures of 900 deg. C for Pb and 800 deg. C for Cd, using a graphite tube with a platform treated with 500 {mu}g Ru as permanent modifier. The reagent concentrations for CPE (HCl, DDTP and Triton X-114) were optimized using a Box-Behnken design. The response surfaces and the optimum values were very similar for aqueous solutions and for the urine samples, demonstrating that aqueous standards submitted to CPE could be used for calibration. Detection limits of 40 and 2 ng L{sup -1} for Pb and Cd, respectively, were obtained along with an enhancement factor of 16 for both analytes. Three control urine samples were analyzed using this approach, and good agreement was obtained at a 95% statistical confidence level between the certified and determined values. Five real samples have also been analyzed before and after spiking with Pb and Cd, resulting in recoveries ranging from 97 to 118%.

  17. Determination of trace copper in water samples by flame atomic absorption spectrometry after preconcentration on a phosphoric acid functionalized cotton chelator

    Directory of Open Access Journals (Sweden)

    XINGYAN LIU

    2008-02-01

    Full Text Available This paper reports the preparation of a phosphorylated cotton chelator (PCC by solid phase esterification of phosphoric acid (PA onto defatted cotton fibres using urea as the catalyst. The synthesized PCC was employed for the preconcentration of copper from water samples prior to its determination by flame atomic absorption spectrometry (FAAS. The preconcentration of copper was studied under both batch and column techniques. The pH range for the quantitative preconcentration of copper was 4.0–7.0. The sorption time required for each sample was less than 30 min by the batch method. The copper sorption capacity of the PCC was found to be 15.3 mg/g at the optimum pH value. Elution with 1.0 mol dm-3 hydrochloric acid was found to be quantitative. Feasible flow rates of the copper solution for quantitative sorption onto the column packed with PCC were 0.5–4.0 ml min-1, whereas the optimum flow rate of the hydrochloric acid solution for desorption was less than 1.5 ml min-1. An 80-fold preconcentration factor could be achieved under the optimum column conditions. The tolerance limits for common metal ions on the preconcentration of copper and the number of times of column reuse were investigated. The proposed method was successfully applied for the preconcentration and determination of trace copper in natural and drinking water samples by FAAS.

  18. 石墨炉原子吸收法测定空气中铋%Determination of bismuth in the air by Graphite Furnace Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    杨雪

    2013-01-01

    建立了硝酸-双氧水体系消解、石墨炉原子吸收法测定空气中铋的方法。采用抗坏血酸和磷酸二氢铵作混合基体改进剂,热解涂层石墨管,塞曼扣背景。此方法对测定环境空气中铋的灵敏度、准确度都有很大的提高,方法的最低检出浓度为1.00μg/L,当采样体积为150L,铋最低检出质量浓度为0.0007mg/m3。%To establish a method for determination of bismuth nitrate in air - hydrogen peroxide system, di-gestion and graphite furnace atomic absorption spectrometry. The ascorbic acid and two hydrogen ammonium phosphate as a mixed matrix modifier, pyrolytic coated graphite tube, Zeeman background correction. The sen-sitivity of this method, determination of bismuth in ambient air the accuracy is greatly improved, the minimum detection limit was 1 μg/L, when the sampling volume was 150L, the minimum detectable concentration of 0. 0007mg/m3 bismuth.

  19. On-line preconcentration system using a microcolumn packed with Alizarin Red S-modified alumina for zinc determination by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    A.M. Haji Shabani

    2009-01-01

    Full Text Available A simple and sensitive on-line flow injection system for determination of zinc with FAAS has been described. The method is based on the separation and preconcentration of zinc on a microcolumn of immobilized Alizarin Red S on alumina. The adsorbed analyte is then eluted with 250 µL of nitric acid (1 mol L-1 and is transported to flame atomic absorption spectrometer for quantification. The effect of pH, sample and eluent flow rates and presence of various cations and anions on the retention of zinc was investigated. The sorption of zinc was quantitative in the pH range of 5.5-8.5. For a sample volume of 25 mL an enrichment factor of 144 and a detection limit (3S of 0.2 µg L-1 was obtained. The precision (RSD, n=7 was 3.0% at the 20 µg L-1 level. The developed system was successfully applied to the determination of zinc in water samples, hair, urine and saliva.

  20. Determination of tellurium in ores, concentrates and related materials by graphite-furnace atomic-absorption spectrometry after separations by iron collection and xanthate extraction.

    Science.gov (United States)

    Donaldson, E M; Leaver, M E

    1990-02-01

    A method for determining approximately 0.01 mug/g or more of tellurium in ores, concentrates, rocks, soils and sediments is described. After sample decomposition and evaporation of the solution to incipient dryness, tellurium is separated from > 300 mug of copper by co-precipitation with hydrous ferric oxide from an ammoniacal medium and the precipitate is dissolved in 10M hydrochloric acid. Alternatively, for samples containing 300 mug of copper, the salts are dissolved in 10M hydrochloric acid. Tellurium in the resultant solutions is reduced to the quadrivalent state by heating and separated from iron, lead and various other elements by a single cyclohexane extraction of its xanthate complex from approximately 9.5M hydrochloric acid in the presence of thiosemicarbazide as a complexing agent for copper. After washing with 10M hydrochloric acid followed by water to remove residual iron, chloride and soluble salts, tellurium is stripped from the extract with 16M nitric acid and finally determined, in a 2% v/v nitric acid medium, by graphite-furnace atomic-absorption spectrometry at 214.3 nm in the presence of nickel as matrix modifier. Small amounts of gold and palladium, which are partly co-extracted as xanthates if the iron-collection step is omitted, do not interfere. Co-extraction of arsenic is avoided by volatilizing it as the bromide during the decomposition step. The method is directly applicable, without the co-precipitation step, to most rocks, soils and sediments.

  1. Preconcentration of Copper Using 1,5-Diphenyl Carbazide as the Complexing Agent via Dispersive Liquid-Liquid Microextraction and Determination by Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Reyhaneh Rahnama

    2013-01-01

    Full Text Available We report a simple and sensitive microextraction system for the preconcentration and determination of Cu (II by flame atomic absorption spectrometry (FAAS. Dispersive liquid-liquid microextraction is a modified solvent extraction method and its acceptor-to-donor phase ratio is greatly reduced compared with other methods. In the proposed approach, 1,5-diphenyl carbazide (DPC was used as a copper ion selective complexing agent. Several variables such as the extraction and dispersive solvent type and volume, pH of sample solution, DPC concentration, extraction time, and ionic strength were studied and optimized for a quantitative preconcentration and determination of copper (II and at the optimized conditions: 60 μL, 0.5 mL, and 5 mL of extraction solvent (chloroform, disperser solvent (ethanol, and sample volume, respectively, a linear calibration graph was obtained over the concentration range of 10–200 μg L−1 for Cu (II with R2 = 0.9966. The limit of detection (3Sb/m, and preconcentration factor are 2 μg L−1 and 25, respectively. The relative standard deviation (n=10 at 100 μg L−1 of Cu (II is 2.5%. The applicability of the developed technique was evaluated by application to spiked environmental water samples.

  2. Determination of sub-microgram amounts of selenium in geological materials by atomic-absorption spectrophotometry with electrothermal atomisation after solvent extraction

    Science.gov (United States)

    Sanzolone, R.F.; Chao, T.T.

    1981-01-01

    An atomic-absorption spectrophotometric method with electrothermal atomisation has been developed for the determination of selenium in geological materials. The sample is decomposed with a mixture of nitric, perchloric and hydrofluoric acids and heated with hydrochloric acid to reduce selenium to selenium (IV). Selenium is then extracted into toluene from a hydrochloric acid - hydrobromic acid medium containing iron. A few microlitres of the toluene extract are injected into a carbon rod atomiser, using a nickel solution as a matrix modifier. The limits of determination are 0.2-200 p.p.m. of selenium in a geological sample. For concentrations between 0.05 and 0.2 p.p.m., back-extraction of the selenium into dilute hydrochloric acid is employed before atomisation. Selenium values for reference samples obtained by replicate analysis are in general agreement with those reported by other workers, with relative standard deviations ranging from 4.1 to 8.8%. Recoveries of selenium spiked at two levels were 98-108%. Major and trace elements commonly encountered in geological materials do not interfere. Arsenic has a suppressing effect on the selenium signals, but only when its concentration is greater than 1000 p.p.m. Nitric acid interferes seriously with the extraction of selenium and must be removed by evaporation in the sample-digestion step.

  3. Determination of β-lactam Antibiotics in Pharmaceutical Preparations by Uv-visible Spectrophotometry Atomic Absorption and High Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    *A. J. Abdulghani

    2012-09-01

    Full Text Available The determination amoxicillin, ampicillin and cephalexin was studied by complexation of the antibiotics with Au(III and Hg(II ions in bulk and pharmaceutical preparations using uv-visible spectrophotometry, atomic absorption, and HPLC techniques. Optimum conditions for complex formation were fixed at pH 4 and (2-4 for Au(III and Hg(IIcomplexes respectively, heating temperature at (60 °C and heating time for (10 minute. All complexes were extracted from aqueous solution with benzyl alcohol prior to measurements except in the case of HPLC. The L:M ratios for all complexes were determined and stability constants were calculated using mole ratio method. The Beer's law was obeyed over the concentration range (5-60 and 5-50 µg/ml of antibiotics for Au(III and Hg(II complexes using colorimetric method and (1-25 µg/ml of Au(III for FAAS. The linearity for HPLC method was (10-110 and 10-120 µg/ml respectively. The correlation coefficients (r were (0.9981-0.9997. Generally, the highest sensitivity was recorded by FAAS.

  4. Trace mercury determination in drinking and natural water samples by room temperature ionic liquid based-preconcentration and flow injection-cold vapor atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Martinis, Estefania M.; Berton, Paula [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT - CONICET - Mendoza), Av. Ruiz Leal S/N Parque General San Martin, CC. 131, M 5502 IRA Mendoza (Argentina); Olsina, Roberto A. [INQUISAL-CONICET, Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, San Luis (Argentina); Altamirano, Jorgelina C. [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT - CONICET - Mendoza), Av. Ruiz Leal S/N Parque General San Martin, CC. 131, M 5502 IRA Mendoza (Argentina); Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza (Argentina); Wuilloud, Rodolfo G., E-mail: rwuilloud@lab.cricyt.edu.ar [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT - CONICET - Mendoza), Av. Ruiz Leal S/N Parque General San Martin, CC. 131, M 5502 IRA Mendoza (Argentina); Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza (Argentina)

    2009-08-15

    A liquid-liquid extraction procedure (L-L) based on room temperature ionic liquid (RTIL) was developed for the preconcentration and determination of mercury in different water samples. The analyte was quantitatively extracted with 1-butyl-3-methylimidazolium hexafluorophosphate ([C{sub 4}mim][PF{sub 6}]) under the form of Hg-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (Hg-5-Br-PADAP) complex. A volume of 500 {mu}l of 9.0 mol L{sup -1} hydrochloric acid was used to back-extract the analyte from the RTIL phase into an aqueous media prior to its analysis by flow injection-cold vapor atomic absorption spectrometry (FI-CV-AAS). A preconcentration factor of 36 was achieved upon preconcentration of 20 mL of sample. The limit of detection (LOD) obtained under the optimal conditions was 2.3 ng L{sup -1} and the relative standard deviation (RSD) for 10 replicates at 1 {mu}g L{sup -1} Hg{sup 2+} was 2.8%, calculated with peaks height. The method was successfully applied to the determination of mercury in river, sea, mineral and tap water samples and a certified reference material (CRM).

  5. Room temperature ionic liquid-based microextraction for vanadium species separation and determination in water samples by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Berton, Paula; Martinis, Estefania M. [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT-CONICET-Mendoza), Av. Ruiz Leal S/N Parque General San Martin, CC. 131, M 5502 IRA Mendoza (Argentina); Martinez, Luis D. [INQUISAL-CONICET, Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis (Argentina); Wuilloud, Rodolfo G., E-mail: rwuilloud@mendoza-conicet.gov.ar [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT-CONICET-Mendoza), Av. Ruiz Leal S/N Parque General San Martin, CC. 131, M 5502 IRA Mendoza (Argentina); Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza (Argentina)

    2009-04-27

    A simple microextraction technique based on room temperature ionic liquids (RTILs) for trace V(IV) and V(V) species separation and preconcentration in water samples was developed in this work. Vanadium species microextraction was achieved with a minimal amount of the RTIL 1-butyl-3-methylimidazolium hexafluorophosphate ([C{sub 4}mim][PF{sub 6}]) as vanadium-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (V-5-Br-PADAP) complex. The speciation analysis was performed based on a modern technique defined as temperature-controlled ionic liquid dispersive liquid phase microextraction (TILDLME). The level of V(IV) species was calculated by difference of total V and V(V) levels. Selectivity among V species was obtained with the use of 1,2-cyclohexanediaminetetraacetic acid (CDTA) as masking agent. Determination of V was developed by direct injection of the RTIL phase into the electrothermal atomic absorption spectrometer (ETAAS). A preconcentration factor of 40 was achieved with only 2 mL of sample. The limit of detection (LOD) obtained under optimum conditions was 4.9 ng L{sup -1} and the relative standard deviation for 10 replicate determinations at the 0.5 {mu}g L{sup -1} V level was 4.3%, calculated at peak heights. A correlation coefficient of 0.9961 was achieved. The method was successfully applied for the speciation analysis of V in tap and river water samples.

  6. The study of applicability of dithiocarbamate-coated fullerene C 60 for preconcentration of palladium for graphite furnace atomic absorption spectrometric determination in environmental samples

    Science.gov (United States)

    Leśniewska, Barbara A.; Godlewska, Iwona; Godlewska—Żyłkiewicz, Beata

    2005-03-01

    The present method comprises an off-line enrichment of Pd on the fullerene, C 60, coated with ammonium pyrrolidinedithiocarbamate (APDC), followed by the elution of formed Pd-chelate with ethanol and the subsequent determination of Pd from the eluate by graphite furnace atomic absorption spectrometry. By using fullerene loaded with 0.1% APDC, the analytical system is simplified as the sample can be directly preconcentrated on the column. The following parameters affecting the preconcentration of Pd on C 60 were optimized: amount of ligand used for the coating of fullerene, sample pH, kind of eluent, sample and eluent flow rates, volume and number of fractions of eluent used. The sorption efficiency for Pd on coated fullerene was 99.2±1.1%. The best elution efficiency for Pd from the column was obtained with 0.6 ml of ethanol at a flow rate of 0.2 ml min -1. The limit of detection was 0.044 ng ml -1. The effect of sample pretreatment procedure on the preconcentration of Pd by evaluated method is discussed. The content of Pd in road dust (179.2±17.4 ng g -1) determined by proposed method was in agreement with the results obtained with a reference method. The low recovery of analyte (64%) was obtained for geological material CRM SARM-7 (platinum ore) due to the much higher concentration of interfering elements.

  7. The study of applicability of dithiocarbamate-coated fullerene C{sub 60} for preconcentration of palladium for graphite furnace atomic absorption spectrometric determination in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Lesniewska, Barbara A. [Institute of Chemistry, University of BiaIystok, Hurtowa 1, 15-399 BiaIystok (Poland); Godlewska, Iwona [Institute of Chemistry, University of BiaIystok, Hurtowa 1, 15-399 BiaIystok (Poland); GodlewskayIkiewicz, Beata [Institute of Chemistry, University of BiaIystok, Hurtowa 1, 15-399 BiaIystok (Poland)]. E-mail: bgodlew@uwb.edu.pl

    2005-03-31

    The present method comprises an off-line enrichment of Pd on the fullerene, C{sub 60}, coated with ammonium pyrrolidinedithiocarbamate (APDC), followed by the elution of formed Pd-chelate with ethanol and the subsequent determination of Pd from the eluate by graphite furnace atomic absorption spectrometry. By using fullerene loaded with 0.1% APDC, the analytical system is simplified as the sample can be directly preconcentrated on the column. The following parameters affecting the preconcentration of Pd on C{sub 60} were optimized: amount of ligand used for the coating of fullerene, sample pH, kind of eluent, sample and eluent flow rates, volume and number of fractions of eluent used. The sorption efficiency for Pd on coated fullerene was 99.2{+-}1.1%. The best elution efficiency for Pd from the column was obtained with 0.6 ml of ethanol at a flow rate of 0.2 ml min{sup -1}. The limit of detection was 0.044 ng ml{sup -1}. The effect of sample pretreatment procedure on the preconcentration of Pd by evaluated method is discussed. The content of Pd in road dust (179.2{+-}17.4 ng g{sup -1}) determined by proposed method was in agreement with the results obtained with a reference method. The low recovery of analyte (64%) was obtained for geological material CRM SARM-7 (platinum ore) due to the much higher concentration of interfering elements.

  8. Determination of Trace Amounts of Palladium in Water Samples by Graphite Furnace Atomic Absorption Spectrometry after Dispersive Liquid-Liquid Microextraction

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Jamali

    2013-01-01

    Full Text Available A simple, rapid, and powerful microextraction technique was used for determination of palladium (II ion in water samples using dispersive liquid-liquid microextraction (DLLME followed by graphite furnace atomic absorption spectrometry (GF AAS. The different variables affecting the complexation and extraction conditions such as extraction and disperser solvent type, extraction time, pH, and concentration of chelating agent were optimized. Under the optimum conditions, the calibration graph was linear in the ranges of 0.05–1 μg L−1 with detection limit of 0.02 μg L−1. The precision (RSD % for ten replicate determination at 0.2 μg L−1 of palladium was better than 3.5% and the enrichment factor 166.5 was obtained from only 5.0 mL of sample. Under the presence of foreign ions, no significant interference was observed. Finally, accuracy and application of the method were estimated by using test samples of natural waters spiked with different amounts of palladium.

  9. Trace mercury determination in drinking and natural water after preconcentration and separation by DLLME-SFO method coupled with cold vapor atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Abdollahi Atousa

    2014-07-01

    Full Text Available A novel dispersive liquid–liquid microextraction based on solidification of floating organic drop (DLLME-SFO for simultaneous separation/preconcentration of ultra trace amounts of mercury was used. A method based on amalgamation was used for collection of gaseous mercury on gold coated sand (Gold trap. The concentration of mercury was determined by cold vapor atomic absorption spectrometry (CV-AAS. The DLLME-SFO behavior of mercury by using dithizone as complexing agent was systematically investigated. The factors influencing, the complex formation and extraction of DLLME-SFO method such as type and volume of extraction and disperser solvents, pH, concentration of salt, centrifuging time and concentration of the chelating agent were optimized. The method was successfully applied to the determination of mercury in drinking and natural water and satisfactory relative recoveries (95–105% were achieved. The proposed procedure was based on very low consumption of organic solvents. The other benefits of the system were sensitive, simple, friendly to the environment, rejection of matrix constituent, low cost, the time consuming and high enrichment factor.

  10. Separation/preconcentration and determination of vanadium with dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFO) and electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Asadollahi, Tahereh; Dadfarnia, Shayessteh; Shabani, Ali Mohammad Haji

    2010-06-30

    A novel dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFO) for separation/preconcentration of ultra trace amount of vanadium and its determination with the electrothermal atomic absorption spectrometry (ETAAS) was developed. The DLLME-SFO behavior of vanadium (V) using N-benzoyl-N-phenylhydroxylamine (BPHA) as complexing agent was systematically investigated. The factors influencing the complex formation and extraction by DLLME-SFO method were optimized. Under the optimized conditions: 100 microL, 200 microL and 25 mL of extraction solvent (1-undecanol), disperser solvent (acetone) and sample volume, respectively, an enrichment factor of 184, a detection limit (based on 3S(b)/m) of 7 ng L(-1) and a relative standard deviation of 4.6% (at 500 ng L(-1)) were obtained. The calibration graph using the preconcentration system for vanadium was linear from 20 to 1000 ng L(-1) with a correlation coefficient of 0.9996. The method was successfully applied for the determination of vanadium in water and parsley.

  11. Determination of Hg(II) in waters by on-line preconcentration using Cyanex 923 as a sorbent — Cold vapor atomic absorption spectrometry

    Science.gov (United States)

    Duan, Taicheng; Song, Xuejie; Xu, Jingwei; Guo, Pengran; Chen, Hangting; Li, Hongfei

    2006-09-01

    Using a solid phase extraction mini-column home-made from a neutral extractant Cyanex 923, inorganic Hg could be on-line preconcentrated and simultaneously separated from methyl mercury. The preconcentrated Hg (II) was then eluted with 10% HNO 3 and subsequently reduced by NaBH 4 to form Hg vapor before determination by cold vapor atomic absorption spectrometry (CVAAS). Optimal conditions for and interferences on the Hg preconcentration and measurement were at 1% HCl, for a 25 mL sample uptake volume and a 10 mL min - 1 sample loading rate. The detection limit was 0.2 ng L - 1 and much lower than that of conventional method (around 15.8 ng L - 1 ). The relative standard deviation (RSD) is 1.8% for measurements of 40 ng L - 1 of Hg and the linear working curve is from 20 to 2000 ng L - 1 (with a correlation coefficient of 0.9996). The method was applied in determination of inorganic Hg in city lake and deep well water (from Changchun, Jilin, China), and recovery test results for both samples were satisfactory.

  12. Determination of Hg(II) in waters by on-line preconcentration using Cyanex 923 as a sorbent - Cold vapor atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Duan Taicheng [State Key Laboratory of Electroanalytical Chemistry, National Research Center of Electroanalytical and Spectroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Song Xuejie [State Key Laboratory of Electroanalytical Chemistry, National Research Center of Electroanalytical and Spectroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Xu Jingwei [State Key Laboratory of Electroanalytical Chemistry, National Research Center of Electroanalytical and Spectroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Guo Pengran [State Key Laboratory of Electroanalytical Chemistry, National Research Center of Electroanalytical and Spectroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Chen Hangting [State Key Laboratory of Electroanalytical Chemistry, National Research Center of Electroanalytical and Spectroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)]. E-mail: htchen@ciac.jl.cn; Li Hongfei [Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2006-09-15

    Using a solid phase extraction mini-column home-made from a neutral extractant Cyanex 923, inorganic Hg could be on-line preconcentrated and simultaneously separated from methyl mercury. The preconcentrated Hg (II) was then eluted with 10% HNO{sub 3} and subsequently reduced by NaBH{sub 4} to form Hg vapor before determination by cold vapor atomic absorption spectrometry (CVAAS). Optimal conditions for and interferences on the Hg preconcentration and measurement were at 1% HCl, for a 25 mL sample uptake volume and a 10 mL min{sup -1} sample loading rate. The detection limit was 0.2 ng L{sup -1} and much lower than that of conventional method (around 15.8 ng L{sup -1}). The relative standard deviation (RSD) is 1.8% for measurements of 40 ng L{sup -1} of Hg and the linear working curve is from 20 to 2000 ng L{sup -1} (with a correlation coefficient of 0.9996). The method was applied in determination of inorganic Hg in city lake and deep well water (from Changchun, Jilin, China), and recovery test results for both samples were satisfactory.

  13. Solidified floating organic drop microextraction (SFODME) for simultaneous separation/preconcentration and determination of cobalt and nickel by graphite furnace atomic absorption spectrometry (GFAAS)

    Energy Technology Data Exchange (ETDEWEB)

    Bidabadi, Mahboubeh Shirani [Department of Chemistry, Yazd University, Safaieh, 89195 Yazd (Iran, Islamic Republic of); Dadfarnia, Shayessteh, E-mail: sdadfarnia@yazduni.ac.ir [Department of Chemistry, Yazd University, Safaieh, 89195 Yazd (Iran, Islamic Republic of); Shabani, Ali Mohammad Haji [Department of Chemistry, Yazd University, Safaieh, 89195 Yazd (Iran, Islamic Republic of)

    2009-07-15

    Solidified floating organic drop microextraction (SFODME), combined with graphite furnace atomic absorption spectrometry (GFAAS) was proposed for simultaneous separation/enrichment and determination of trace amounts of nickel and cobalt in surface waters and sea water. 1-(2-Pyridylazo)-2-naphthol (PAN) was used as chelating agent. The main parameters affecting the performance of SFODME, such as pH, concentration of PAN, extraction time, stirring rate, extraction temperature, sample volume and nature of the solvent were optimized. Under the optimum experimental conditions, a good relative standard deviation for six determination of 20 ng l{sup -1} of Co(II) and Ni(II) were 4.6 and 3.6%, respectively. An enrichment factor of 502 and 497 and detection limits of 0.4 and 0.3 ng l{sup -1} for cobalt and nickel were obtained, respectively. The procedure was applied to tap water, well water, river water and sea water, and accuracy was assessed through the analysis of certified reference water or recovery experiments.

  14. Solidified floating organic drop microextraction (SFODME) for simultaneous separation/preconcentration and determination of cobalt and nickel by graphite furnace atomic absorption spectrometry (GFAAS).

    Science.gov (United States)

    Bidabadi, Mahboubeh Shirani; Dadfarnia, Shayessteh; Shabani, Ali Mohammad Haji

    2009-07-15

    Solidified floating organic drop microextraction (SFODME), combined with graphite furnace atomic absorption spectrometry (GFAAS) was proposed for simultaneous separation/enrichment and determination of trace amounts of nickel and cobalt in surface waters and sea water. 1-(2-Pyridylazo)-2-naphthol (PAN) was used as chelating agent. The main parameters affecting the performance of SFODME, such as pH, concentration of PAN, extraction time, stirring rate, extraction temperature, sample volume and nature of the solvent were optimized. Under the optimum experimental conditions, a good relative standard deviation for six determination of 20 ng l(-1) of Co(II) and Ni(II) were 4.6 and 3.6%, respectively. An enrichment factor of 502 and 497 and detection limits of 0.4 and 0.3 ng l(-1) for cobalt and nickel were obtained, respectively. The procedure was applied to tap water, well water, river water and sea water, and accuracy was assessed through the analysis of certified reference water or recovery experiments.

  15. A novel solidified floating organic drop microextraction method for preconcentration and determination of copper ions by flow injection flame atomic absorption spectrometry in water samples

    Directory of Open Access Journals (Sweden)

    Arpa Şahin Ç.

    2013-04-01

    Full Text Available A simple, rapid and inexpensive solidified floating organic drop microextraction (SFODME and flow injection flame atomic absorption spectrometric determination (FI-FAAS method for copper was developed. 3-amino-7-dimethylamino-2-methylphenazine (Neutral red, NR was used as the complexing agent. Several factors affecting the microextraction efficiency, such as, pH, NR and sodium dodecylbenzenesulfonate (SDBS concentration, extraction time, stirring rate, and temperature were investigated and optimized. Under optimized experimental conditions an enrichment factor of 541 was obtained for 100 mL of sample solution. The calibration graph was linear in the range of 0.5 – 20.0 ng mL–1 and the limit of detection (3s was 0.18 ng mL–1, the limit of quantification (10s was 0.58 ng mL–1. The relative standard deviation (RSD for 10 replicate measurements of 10 ng mL–1 copper was 2.7%. The developed method was successfully applied to the extraction and determination of copper in different certified reference materials (Estuarine water, Slew 3 and fortified water, TM 23.2 and real water samples and satisfactory results were obtained.

  16. Solid phase extraction method for the determination of iron, lead and chromium by atomic absorption spectrometry using Amberite XAD-2000 column in various water samples

    Energy Technology Data Exchange (ETDEWEB)

    Elci, Latif [Chemistry Department, Science and Arts Faculty, Pamukkale University, Denizli (Turkey)], E-mail: elci@pamukkale.edu.tr; Kartal, Aslihan A. [Chemistry Department, Science and Arts Faculty, Pamukkale University, Denizli (Turkey); Soylak, Mustafa [Chemistry Department, Science and Arts Faculty, Erciyes University, Kayseri (Turkey)

    2008-05-01

    This work describes a procedure for the separation-preconcentration of Fe(III), Pb(II) and Cr(III) from some water samples using a column-filled Amberlite XAD-2000 resin. The analyte ions retained on the column were eluted with 0.5 mol L{sup -1} HNO{sub 3}. The analytes in the effluent were determined by atomic absorption spectrometry. Several parameters governing the efficiency of the method were evaluated including pH, resin amount, sample volume, flow rates, eluent type and divers ion effects. The recoveries under the optimum working conditions were found to be as 100 {+-} 1% Fe, 96 {+-} 1% Pb and 93 {+-} 2% Cr. The relative standard deviations and errors were less than 2% and 5%, respectively. The detection limit based on three standard deviations of the blank was found to be 0.32, 0.51 and 0.81 {mu}g L{sup -1}, for Fe, Pb and Cr, respectively. The procedure was applied to the determination of Fe, Cr and Pb in hot spring water and drinking water samples.

  17. Dispersive liquid-liquid microextraction based on solidification of floating organic drop for preconcentration and determination of trace amounts of copper by flame atomic absorption spectrometry.

    Science.gov (United States)

    Karadaş, Cennet; Kara, Derya

    2017-04-01

    A novel, simple, rapid, sensitive, inexpensive and environmentally friendly dispersive liquid-liquid microextraction method based on the solidification of a floating organic drop (DLLME-SFO) was developed for the determination of copper by flame atomic absorption spectrometry (FAAS). N-o-Vanillidine-2-amino-p-cresol was used as a chelating ligand and 1-undecanol was selected as an extraction solvent. The main parameters affecting the performance of DLLME-SFO, such as sample pH, volume of extraction solvent, extraction time, concentration of the chelating ligand, salt effect, centrifugation time and sample volume were investigated and optimized. The effect of interfering ions on the recovery of copper was also examined. Under the optimum conditions, the detection limit (3σ) was 0.93μgL(-1) for Cu using a sample volume of 20mL, yielding a preconcentration factor of 20. The proposed method was successfully applied to the determination of Cu in tap, river and seawater, rice flour and black tea samples as well as certified reference materials.

  18. Cloud point extraction for the determination of lead and cadmium in urine by graphite furnace atomic absorption spectrometry with multivariate optimization using Box Behnken design

    Science.gov (United States)

    Maranhão, Tatiane De A.; Martendal, Edmar; Borges, Daniel L. G.; Carasek, Eduardo; Welz, Bernhard; Curtius, Adilson J.

    2007-09-01

    Cloud point extraction (CPE) is proposed as a pre-concentration procedure for the determination of Pb and Cd in undigested urine by graphite furnace atomic absorption spectrometry (GF AAS). Aliquots of 0.5 mL urine were acidified with HCl and the chelating agent ammonium O,O-diethyl dithiophosphate (DDTP) was added along with the non-ionic surfactant Triton X-114 at the optimized concentrations. Phase separation was achieved by heating the mixture to 50 °C for 15 min. The surfactant-rich phase was analyzed by GF AAS, employing the optimized pyrolysis temperatures of 900 °C for Pb and 800 °C for Cd, using a graphite tube with a platform treated with 500 μg Ru as permanent modifier. The reagent concentrations for CPE (HCl, DDTP and Triton X-114) were optimized using a Box Behnken design. The response surfaces and the optimum values were very similar for aqueous solutions and for the urine samples, demonstrating that aqueous standards submitted to CPE could be used for calibration. Detection limits of 40 and 2 ng L- 1 for Pb and Cd, respectively, were obtained along with an enhancement factor of 16 for both analytes. Three control urine samples were analyzed using this approach, and good agreement was obtained at a 95% statistical confidence level between the certified and determined values. Five real samples have also been analyzed before and after spiking with Pb and Cd, resulting in recoveries ranging from 97 to 118%.

  19. Preconcentration of lead, cadmium and zinc on silica gel loaded with diethyldithiocarbamate prior to their determination by flame-atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Rio-Segade, S. [Dept. de Quimica Analitica y Alimentaria, Univ. de Vigo, Orense (Spain); Perez-Cid, B. [Dept. de Quimica Analitica y Alimentaria, Univ. de Vigo, Orense (Spain); Bendicho, C. [Dept. de Quimica Analitica y Alimentaria, Univ. de Vigo, Orense (Spain)

    1995-04-01

    A silica gel sorbent loaded with sodium diethyldithiocarbamate has been developed for the preconcentration of lead, cadmium and zinc prior to their determination by flame-atomic absorption spectrometry (FAAS). The sorption and desorption of the metal ions was studied under both static and dynamic conditions. The metal ions were quantitatively retained on the silica gel sorbent based on an equilibrium time of less than 1 min. In case of the batch method, the effects of pH, shaking time, amount of sorbent, and desorption time were investigated. Among the desorption agents studied, only EDTA in ammonium chloride/ammonia buffer yielded quantitative recoveries. Freundlich`s sorption isotherms determined for each metal show that sufficient sorption ability is obtained. The column method allows the preconcentration of metal ions from large sample volumes (e.g. 200 mL) using a flow rate of 5 mL min{sup -1}. The influence of foreign ions present in natural waters and saline solutions was examined. The reproducibility of the total analytical method, expressed as relative standard deviation (RSD) is 1.8, 0.5 and 0.6%, for lead, cadmium and zinc, respectively. (orig.)

  20. Solid phase extraction method for the determination of iron, lead and chromium by atomic absorption spectrometry using Amberite XAD-2000 column in various water samples.

    Science.gov (United States)

    Elci, Latif; Kartal, Aslihan A; Soylak, Mustafa

    2008-05-01

    This work describes a procedure for the separation-preconcentration of Fe(III), Pb(II) and Cr(III) from some water samples using a column-filled Amberlite XAD-2000 resin. The analyte ions retained on the column were eluted with 0.5 mol L(-1) HNO(3). The analytes in the effluent were determined by atomic absorption spectrometry. Several parameters governing the efficiency of the method were evaluated including pH, resin amount, sample volume, flow rates, eluent type and divers ion effects. The recoveries under the optimum working conditions were found to be as 100+/-1% Fe, 96+/-1% Pb and 93+/-2% Cr. The relative standard deviations and errors were less than 2% and 5%, respectively. The detection limit based on three standard deviations of the blank was found to be 0.32, 0.51 and 0.81 microg L(-1), for Fe, Pb and Cr, respectively. The procedure was applied to the determination of Fe, Cr and Pb in hot spring water and drinking water samples.

  1. Biosorption of platinum and palladium for their separation/preconcentration prior to graphite furnace atomic absorption spectrometric determination

    Energy Technology Data Exchange (ETDEWEB)

    Godlewska-Zylkiewicz, Beata E-mail: bgodlew@uwb.edu.pl

    2003-08-15

    Inexpensive baker's yeast Saccharomyces cerevisiae and green algae Chlorella vulgaris, either free or immobilized on silica gel have been shown to selectively accumulate platinum and palladium from water samples in acidic medium (pH 1.6-1.8). Optimization of conditions of metals biosorption (sample pH, algae and yeast masses, adsorption time, temperature) was performed in batch mode. The procedure of matrix separation based on biosorption of platinum and palladium on algae C. vulgaris covalently immobilized on silica gel in flow mode was developed. The use of algae in flow procedure offers several advantages compared with its use in the batch mode. The procedure shows better reproducibility (<2%), improved efficiency of platinum retention on the column (93.3{+-}1.6%), is less laborious and less time consuming. The best recovery of biosorbed metals from column (87.7{+-}3.3% for platinum and 96.8{+-}1.1 for palladium) was obtained with solution of 0.3 mol l{sup -1} thiourea in 1 mol l{sup -1} hydrochloric acid. The influence of thiourea on analytical signals of examined metals during GFAAS determination is discussed. The procedure has been applied for separation of noble metals from tap and waste water samples spiked with platinum and palladium.

  2. Metal ion determination by flame atomic absorption spectrometry through reagentless coacervate phase separation-extraction into lamellar vesicles.

    Science.gov (United States)

    Giokas, Dimosthenis L; Tsogas, George Z; Vlessidis, Athanasios G; Karayannis, Miltiades I

    2004-03-01

    The phase separation of lamellar vesicles of anionic surfactants in aqueous solutions and its application as a novel liquid coacervate extraction procedure was examined. Solutions of lauric acid sodium salt separate into two phases in the presence of alkaline earth metals and a water miscible cosurfactant. It is proven that the surfactant phase is built of a perplexed network of multilamellar vesicles consisting of densely packed bilayers. Several factors affecting the formation of this new phase as well as its analytical utility in the preconcentration of metallic ions were assessed on the basis of better exploitation of this new nonspecific extraction technique. In essence, although the procedure to arrive at the optimum conditions seems laborious, the delivered method is straightforward, alleviating the requirement for prereaction with a complexing agent and highly reproducible under the optimum experimental conditions. As an analytical demonstration, the method was successfully applied to the determination of Cd(2+) and Zn(2+) in natural waters. Recoveries were higher than 95%, and detection limits as low as 3 microg L(-)(1) were accomplished by preconcentrating only 10 mL of sample volume in the presence of 0.45% (w/v) anionic surfactant.

  3. Ultratrace determination of lead by hydride generation in-atomizer trapping atomic absorption spectrometry: Optimization of plumbane generation and analyte preconcentration in a quartz trap-and-atomizer device

    Energy Technology Data Exchange (ETDEWEB)

    Kratzer, Jan, E-mail: jkratzer@biomed.cas.cz

    2012-05-15

    A compact trap-and-atomizer device and a preconcentration procedure based on hydride trapping in excess of oxygen over hydrogen in the collection step, both constructed and developed previously in our laboratory, were employed to optimize plumbane trapping in this device and to develop a routine method for ultratrace lead determination subsequently. The inherent advantage of this preconcentration approach is that 100% preconcentration efficiency for lead is reached in this device which has never been reported before using quartz or metal traps. Plumbane is completely retained in the trap-and-atomizer device at 290 Degree-Sign C in oxygen-rich atmosphere and trapped species are subsequently volatilized at 830 Degree-Sign C in hydrogen-rich atmosphere. Effect of relevant experimental parameters on plumbane trapping and lead volatilization are discussed, and possible trapping mechanisms are hypothesized. Plumbane trapping in the trap-and-atomizer device can be routinely used for lead determination at ultratrace levels reaching a detection limit of 0.21 ng ml{sup -1} Pb (30 s preconcentration, sample volume 2 ml). Further improvement of the detection limit is feasible by reducing the blank signal and increasing the trapping time. - Highlights: Black-Right-Pointing-Pointer In-atomizer trapping HG-AAS was optimized for Pb. Black-Right-Pointing-Pointer A compact quartz trap-and-atomizer device was employed. Black-Right-Pointing-Pointer Generation, preconcentration and atomization steps were investigated in detail. Black-Right-Pointing-Pointer 100% preconcentration efficiency for lead was reached. Black-Right-Pointing-Pointer Routine analytical method was developed for Pb determination (LOD of 0.2 ng ml{sup -1} Pb).

  4. Feasibility of dispersive liquid–liquid microextraction for extraction and preconcentration of Cu and Fe in red and white wine and determination by flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Seeger, Tassia S.; Rosa, Francisco C.; Bizzi, Cezar A.; Dressler, Valderi L.; Flores, Erico M.M.; Duarte, Fabio A., E-mail: fabioand@gmail.com

    2015-03-01

    A method for extraction and preconcentration of Cu and Fe in red and white wines using dispersive liquid–liquid microextraction (DLLME) and determination by flame atomic absorption spectrometry (F AAS) was developed. Extraction was performed using sodium diethyldithiocarbamate as chelating agent and a mixture of 40 μL of 1,2-dichlorobenzene (extraction solvent) and 900 μL of methanol (dispersive solvent). Some parameters that influencing the extraction efficiency such as pH (2 to 5), concentration of chelating agent (0 to 2%), effect of salt addition (0 to 10%), number of washing steps (1 to 4) and centrifugation time (0 to 15 min) were studied. Accuracy was evaluated after microwave-assisted digestion in closed vessels and analytes were determined by inductively coupled plasma optical emission spectrometry. Agreement with the proposed method ranged from 91 to 110 and from 89 to 113% for Cu and Fe, respectively. Calibration of F AAS instrument was performed using analyte addition method and limits of detection were 6.3 and 2.4 μg L{sup −1} for Cu and Fe, respectively. The proposed method was applied for the determination of Cu and Fe in five samples of red wine and three samples of white wine, with concentration ranging from 21 to 178 μg L{sup −1} and from 1.38 to 3.74 mg L{sup −1}, respectively. - Highlights: • Determination of Cu and Fe in wine using DLLME and F AAS • High preconcentration factors and low LODs were achieved. • Alternative method for the determination of Cu and Fe in wine for routine analysis.

  5. Ultrasound-assisted single-drop microextraction for the determination of cadmium in vegetable oils using high-resolution continuum source electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Jorge S.; Anunciação, Taiana A. [Departamento de Química Analítica, Instituto de Química, Universidade Federal da Bahia, Campus Universitário de Ondina, Salvador, Bahia 40170-280 (Brazil); Brandão, Geovani C. [Departamento de Química Analítica, Instituto de Química, Universidade Federal da Bahia, Campus Universitário de Ondina, Salvador, Bahia 40170-280 (Brazil); INCT de Energia e Ambiente, Instituto de Química, Universidade Federal da Bahia, Campus Universitário de Ondina, Salvador, Bahia 40170-280 (Brazil); Dantas, Alailson F. [Departamento de Química Analítica, Instituto de Química, Universidade Federal da Bahia, Campus Universitário de Ondina, Salvador, Bahia 40170-280 (Brazil); Lemos, Valfredo A. [Laboratório de Química Analítica (LQA), Universidade Estadual do Sudoeste da Bahia, Campus de Jequié, Jequié, Bahia 45506-191 (Brazil); and others

    2015-05-01

    This work presents an ultrasound-assisted single-drop microextraction procedure for the determination of cadmium in vegetable oils using high-resolution continuum source electrothermal atomic absorption spectrometry. Some initial tests showed that the best extraction efficiency was obtained when using ultrasound instead of mechanical agitation, indicating that acoustic cavitation improved the extraction process. Nitric, hydrochloric and acetic acids were evaluated for use in the extraction process, and HNO{sub 3} gave the best results. A two-level full-factorial design was applied to investigate the best conditions for the extraction of Cd from the oil samples. The influences of the sonication amplitude, time and temperature of the extraction were evaluated. The results of the design revealed that all of the variables had a significant effect on the experimental results. Afterward, a Box–Behnken design was applied to determine the optimum conditions for the determination of cadmium in vegetable oil samples. According to a multivariate study, the optimum conditions were as follows: sonication amplitude of 60%, extraction time of 15 min, extraction temperature of 46 °C and 0.1 mol L{sup −1} HNO{sub 3} as the extractor solution. Under optimized conditions, the developed method allows for the determination of Cd in oil samples with a limit of quantification of 7.0 ng kg{sup −1}. Addition and recovery experiments were performed in vegetable oil samples to evaluate the accuracy of the method, and the recoveries obtained varied from 90% to 115%. The samples were also analyzed after the acid digestion procedure, and the paired t-test (95% confidence level) did not show significant differences from the proposed method. - Highlights: • The determination of cadmium in vegetable oils was developed using UA-SDME. • HR-CS ET-AAS was employed as a detection technique with direct drop sampling. • The procedure allowed for a reduction in the consumption of reagents and

  6. Method development for the determination of fluorine in water samples via the molecular absorption of strontium monofluoride formed in an electrothermal atomizer

    Energy Technology Data Exchange (ETDEWEB)

    Ozbek, Nil, E-mail: nil.ozbek@itu.edu.tr; Akman, Suleyman, E-mail: akmans@itu.edu.tr

    2012-03-15

    The presence of fluorine (F) was detected via the rotational molecular absorption line of diatomic strontium-monofluoride (SrF) generated in the gas phase at 651.187 nm using high-resolution continuum source electrothermal atomic absorption spectrometry. Upon the addition of excess strontium (Sr) as the nitrate, the fluorine in the sample was converted to SrF in the gas phase of a graphite furnace. The effects on the accuracy, precision and sensitivity of variables such as the SrF wavelength, graphite furnace program, amount of Sr, coating of the graphite tube and platform with Zr and Ir and the use of a modifier were investigated and optimized. It was determined that there was no need to use a modifier or to cover the platform/tubes with Zr or Ir. Fluorine concentrations in various water samples (certified waste water, tap water, drinking water and mineral water) were determined using 20 {mu}g of Sr as the molecule-forming reagent and applying a maximum pyrolysis temperature of 800 Degree-Sign C and a molecule-forming temperature of 2200 Degree-Sign C with a heating rate of 2000 Degree-Sign C s{sup -1}. Good linearity was maintained up to 0.1 {mu}g of F. The accuracy and precision of the method were tested by analyzing certified reference wastewater. The results were in good agreement with certified values, and the precision was satisfactory (RSD < 10%). The limit of detection and the characteristic mass for the method were 0.36 ng and 0.55 ng, respectively. Finally, the fluorine concentrations in several drinking water and mineral water samples taken from the market were determined. The results were in good agreement with the values supplied by the producers. No significant differences were found between the results from the linear calibration and standard addition techniques. The method was determined to be simple, fast, accurate and sensitive. - Highlights: Black-Right-Pointing-Pointer F is determined via MAS of SrF at 651.187 nm using HR-CS-ET AAS. Black

  7. Principles and calibration of collinear photofragmentation and atomic absorption spectroscopy

    Science.gov (United States)

    Sorvajärvi, Tapio; Toivonen, Juha

    2014-06-01

    The kinetics of signal formation in collinear photofragmentation and atomic absorption spectroscopy (CPFAAS) are discussed, and theoretical equations describing the relation between the concentration of the target molecule and the detected atomic absorption in case of pure and impure samples are derived. The validity of the equation for pure samples is studied experimentally by comparing measured target molecule concentrations to concentrations determined using two other independent techniques. Our study shows that CPFAAS is capable of measuring target molecule concentrations from parts per billion (ppb) to hundreds of parts per million (ppm) in microsecond timescale. Moreover, the possibility to extend the dynamic range to cover eight orders of magnitude with a proper selection of fragmentation light source is discussed. The maximum deviation between the CPFAAS technique and a reference measurement technique is found to be less than 5 %. In this study, potassium chloride vapor and atomic potassium are used as a target molecule and a probed atom, respectively.

  8. Determinations of Sb and Mo in Cairo's dust using high-resolution continuum source graphite furnace atomic absorption spectrometry and direct solid sample analysis

    Science.gov (United States)

    Shaltout, Abdallah A.; Welz, Bernhard; Castilho, Ivan N. B.

    2013-12-01

    The present work describes the determination of Sb and Mo in dust deposited on tree leaves using direct solid sample analysis. Nineteen air particulate samples were collected from different districts of Cairo and surrounding cities. Since some samples have been taken from places less exposed to the pollution factors, the present study allows the comparison of air quality between high and low polluted areas. High-resolution continuum source graphite furnace atomic absorption spectrometry has been investigated, using direct solid sample analysis. The optimum pyrolysis and atomization temperatures for Sb were found to be 800 °C and 1900 °C, and 1200 °C and 2650 °C, respectively for Mo. The limits of detection and quantification for both, Sb and Mo, were 15 μg g-1 and 50 ng g-1, respectively. The characteristic mass at was found to be m0 = 38 pg for Sb (217.582 nm) and m0 = 28 pg for Mo (313.259 nm). The results obtained for three certified reference materials of urban particulate matter confirmed the validity of the investigated method. The content of Sb varied between 213 ± 1.3 μg g-1 and 1117 ± 230 μg g-1 with an average of 667 ± 339 μg g-1. On the other hand, the Mo content varied from 113 ± 2.3 μg g-1 to 361 ± 51 μg g-1 and its average value equals 190 ± 62 μg g-1.

  9. Determination of lead, cadmium, copper, and nickel in the tonghui river of beijing, china, by cloud point extraction-high resolution continuum source graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Ren, Ting; Zhao, Li-Jiao; Sun, Bo-Si; Zhong, Ru-Gang

    2013-11-01

    Heavy metal contamination of water has become an important problem in recent years. Most hazardous heavy metals exist in environmental water in trace or ultra-trace amounts, which requires establishing highly sensitive analytical methods. In this research, quantitative analyses were performed using high-resolution continuum source graphite furnace atomic absorption spectrometry combined with cloud point extraction (CPE) to determine Pb, Cd, Cu, and Ni levels in environmental surface water. By optimizing the CPE conditions, the enrichment factors were 29 for Pb, Cd, and Cu and 25 for Ni. The limits of detection (LOD) were 0.080, 0.010, 0.035, and 0.014 μg L for Pb, Cd, Cu, and Ni, respectively. The sensitivity of the method is comparable with those reported in previous investigations using various methods and improves outcome by 2 to 3 orders of magnitude compared with the LODs of the current national standard methods of China. Our method was used to determine Pb, Cd, Cu, and Ni in 55 water samples collected from the Tonghui River, which is the principal river in the urban area of Beijing, China. The results indicated that the distributions of the four heavy metals in the Tonghui River were related with the environments. The levels of Pb and Ni exhibit increasing trends along the river from upstream to downstream possibly due to the existence of some chemical factories in the downstream area. Lead, Cd, Cu, and Ni averaged 13.9, 0.8, 46.8, and 38.5%, respectively, of the total amount of the determined heavy metals. The levels of the four heavy metals conformed to the Environmental Quality Standards for Surface Water (Grade I) of China. This work provides a reliable quantitative method to determine trace-amount heavy metals in water, which lays a foundation for establishing standards and regulations for environmental water protection.

  10. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of low-level silver by graphite furnace atomic absorption spectrophotometry

    Science.gov (United States)

    Damrau, D.L.

    1993-01-01

    Increased awareness of the quality of water in the United States has led to the development of a method for determining low levels (0.2-5.0 microg/L) of silver in water samples. Use of graphite furnace atomic absorption spectrophotometry provides a sensitive, precise, and accurate method for determining low-level silver in samples of low ionic-strength water, precipitation water, and natural water. The minimum detection limit determined for low-level silver is 0.2 microg/L. Precision data were collected on natural-water samples and SRWS (Standard Reference Water Samples). The overall percent relative standard deviation for natural-water samples with silver concentrations more than 0.2 microg/L was less than 40 percent throughout the analytical range. For the SRWS with concentrations more than 0.2 microg/L, the overall percent relative standard deviation was less than 25 percent throughout the analytical range. The accuracy of the results was determined by spiking 6 natural-water samples with different known concentrations of the silver standard. The recoveries ranged from 61 to 119 percent at the 0.5-microg/L spike level. At the 1.25-microg/L spike level, the recoveries ranged from 92 to 106 percent. For the high spike level at 3.0 microg/L, the recoveries ranged from 65 to 113 percent. The measured concentrations of silver obtained from known samples were within the Branch of Quality Assurance accepted limits of 1 1/2 standard deviations on the basis of the SRWS program for Inter-Laboratory studies.

  11. Preconcentration and Determination of Copper(Ⅱ) Using Octadecyl Silica Membrane Disks Modified by 1,5-Diphenylcarhazide and Flame Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    MOGHIMI Ali

    2007-01-01

    A simple and reproducible method for the rapid extraction and determination of trace amounts of copper(Ⅱ)ions using octadecyl-bonded silica membrane disks modified by 1,5-diphenylcarbazide (DPC) and atomic absorption spectrometry was presented, which was based on complex formation on the surface of the ENVI-18 DISKTM disks followed by stripping of the retained species by minimum amounts of appropriate organic solvents. The elution was efficient and quantitative. The effect of potential interfering ions, pH, ligand amount, stripping solvent, and sample flow rate were also investigated. Under the optimal experimental conditions, the break-through volume was found to be about 1000 mL providing a preconcentration factor of 400. The maximum capacity of the disks was found to be (255±5) μg for Cu2+, and the limit of detection of the proposed method was 5 ng per 1000 mL. The method was applied to the extraction and recovery of copper in different water samples.

  12. Accuracy of a method based on atomic absorption spectrometry to determine inorganic arsenic in food: Outcome of the collaborative trial IMEP-41.

    Science.gov (United States)

    Fiamegkos, I; Cordeiro, F; Robouch, P; Vélez, D; Devesa, V; Raber, G; Sloth, J J; Rasmussen, R R; Llorente-Mirandes, T; Lopez-Sanchez, J F; Rubio, R; Cubadda, F; D'Amato, M; Feldmann, J; Raab, A; Emteborg, H; de la Calle, M B

    2016-12-15

    A collaborative trial was conducted to determine the performance characteristics of an analytical method for the quantification of inorganic arsenic (iAs) in food. The method is based on (i) solubilisation of the protein matrix with concentrated hydrochloric acid to denature proteins and allow the release of all arsenic species into solution, and (ii) subsequent extraction of the inorganic arsenic present in the acid medium using chloroform followed by back-extraction to acidic medium. The final detection and quantification is done by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS). The seven test items used in this exercise were reference materials covering a broad range of matrices: mussels, cabbage, seaweed (hijiki), fish protein, rice, wheat, mushrooms, with concentrations ranging from 0.074 to 7.55mgkg(-1). The relative standard deviation for repeatability (RSDr) ranged from 4.1 to 10.3%, while the relative standard deviation for reproducibility (RSDR) ranged from 6.1 to 22.8%.

  13. Automatic flow-batch system for cold vapor atomic absorption spectroscopy determination of mercury in honey from Argentina using online sample treatment.

    Science.gov (United States)

    Domínguez, Marina A; Grünhut, Marcos; Pistonesi, Marcelo F; Di Nezio, María S; Centurión, María E

    2012-05-16

    An automatic flow-batch system that includes two borosilicate glass chambers to perform sample digestion and cold vapor atomic absorption spectroscopy determination of mercury in honey samples was designed. The sample digestion was performed by using a low-cost halogen lamp to obtain the optimum temperature. Optimization of the digestion procedure was done using a Box-Behnken experimental design. A linear response was observed from 2.30 to 11.20 μg Hg L(-1). The relative standard deviation was 3.20% (n = 11, 6.81 μg Hg L(-1)), the sample throughput was 4 sample h(-1), and the detection limit was 0.68 μg Hg L(-1). The obtained results with the flow-batch method are in good agreement with those obtained with the reference method. The flow-batch system is simple, allows the use of both chambers simultaneously, is seen as a promising methodology for achieving green chemistry goals, and is a good proposal to improving the quality control of honey.

  14. Determination of nickel in food samples by flame atomic absorption spectroscopy after preconcentration and microextraction based ionic liquids using full factorial and central composite design.

    Science.gov (United States)

    Zarei, Zohre; Shemirani, Farzaneh

    2012-12-01

    In this research, a microextraction technique based on ionic liquids (ILs) termed in situ solvent formation microextraction (ISFME) was used for determination of nickel in solutions. 1-(2-pyridylazo)-2-naphtol (PAN) was chosen as a complexing agent. After preconcentration, the settled IL-phase was dissolved in 50 μL of ethanol and aspirated into the flame atomic absorption spectrometer (FAAS) using a home-made microsample introduction system. Injection of 50 μL volumes of analyte into an air-acetylene flame provided very sensitive spike-like and reproducible signals. ISFME is based on phase separation phenomenon of ionic liquids in aqueous solutions. This method is simple and rapid for extraction and preconcentration of metal ions from food samples and can be applied for the sample solutions containing very high concentrations of salt. Furthermore, this technique is much safer in comparison with the organic solvent extraction because of using ionic liquid. The effective parameters such as amount of IL, salt effect, concentration of the chelating agent and ion pairing agent were inspected by a full factorial design to identify important parameters and their interactions. Next, a central composite design was applied to obtain optimum point of the important parameters. Under the optimum conditions, the calibration graph was linear over the range of 2 to 80 ng/mL. The limit of detection and relative standard deviation (n= 6) were 0.6 ng/mL and 2%, respectively.

  15. Tandem focused ultrasound (TFU) combined with fast furnace analysis as an improved methodology for total mercury determination in human urine by electrothermal-atomic absorption spectrometry.

    Science.gov (United States)

    Capelo, J L; Dos Reis, C D; Maduro, C; Mota, A

    2004-09-01

    A new sample preparation procedure based on tandem (that is, different diameter probe sonicators used in the same sample treatment) focused ultrasound (TFU) for mercury separation, preconcentration and back-extraction in aqueous solution from human urine has been developed. The urine is first oxidized with KMnO(4)/HCl/focused ultrasound (6mm probe). Secondly, the mercury is extracted and preconcentrated with dithizone and cyclohexane. Finally, the mercury is back-extracted and preconcentrated again with the aid of focused ultrasound (3mm probe). The procedure allows determining mercury by electrothermal atomic absorption spectrometry with fast furnace analysis and calibration against aqueous standards. Matrix modification is provided by the chemicals used in the sample treatment. The procedure is accomplished with low sample volume (8.5ml). Low volume and low concentration reagents are used. The sample treatment is rapid (less than 3min per sample) and avoids the use of organic phase in the graphite furnace. The preconcentration factor used in this work was 14. The limit of detection and the limit of quantification in urine were, respectively, 0.27 and 0.9mugl(-1). The relative standard deviation of aqueous standards (n=10) was 4% for a concentration of 100mugl(-1) and 5% for a concentration of 400mugl(-1). Recoveries from spiked urine with inorganic mercury, methyl-mercury, phenyl-mercury and diphenyl-mercury ranged from 86 to 98%.

  16. Cloud point extraction and flame atomic absorption spectrometric determination of cadmium(II), lead(II), palladium(II) and silver(I) in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Ghaedi, Mehrorang, E-mail: m_ghaedi@mail.yu.ac.ir [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of); Shokrollahi, Ardeshir [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of); Niknam, Khodabakhsh [Chemistry Department, Persian Gulf University, Bushehr (Iran, Islamic Republic of); Niknam, Ebrahim; Najibi, Asma [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of); Soylak, Mustafa [Chemistry Department, University of Erciyes, 38039 Kayseri (Turkey)

    2009-09-15

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of cadmium(II), lead(II), palladium(II) and silver(I). The analytical procedure involved the formation of understudy metals complex with bis((1H-benzo [d] imidazol-2yl)ethyl) sulfane (BIES), and quantitatively extracted to the phase rich in octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 1 mol L{sup -1} HNO{sub 3} was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The concentration of BIES, pH and amount of surfactant (Triton X-114) was optimized. At optimum conditions, the detection limits of (3 sdb/m) of 1.4, 2.8, 1.6 and 1.4 ng mL{sup -1} for Cd{sup 2+}, Pb{sup 2+}, Pd{sup 2+} and Ag{sup +} along with preconcentration factors of 30 and enrichment factors of 48, 39, 32 and 42 for Cd{sup 2+}, Pb{sup 2+}, Pd{sup 2+} and Ag{sup +}, respectively, were obtained. The proposed cloud point extraction has been successfully applied for the determination of metal ions in real samples with complicated matrix such as radiology waste, vegetable, blood and urine samples.

  17. Cloud point extraction and flame atomic absorption spectrometric determination of cadmium(II), lead(II), palladium(II) and silver(I) in environmental samples.

    Science.gov (United States)

    Ghaedi, Mehrorang; Shokrollahi, Ardeshir; Niknam, Khodabakhsh; Niknam, Ebrahim; Najibi, Asma; Soylak, Mustafa

    2009-09-15

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of cadmium(II), lead(II), palladium(II) and silver(I). The analytical procedure involved the formation of understudy metals complex with bis((1H-benzo [d] imidazol-2yl)ethyl) sulfane (BIES), and quantitatively extracted to the phase rich in octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 1molL(-1) HNO(3) was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The concentration of BIES, pH and amount of surfactant (Triton X-114) was optimized. At optimum conditions, the detection limits of (3 sdb/m) of 1.4, 2.8, 1.6 and 1.4 ng mL(-1) for Cd(2+), Pb(2+), Pd(2+) and Ag(+) along with preconcentration factors of 30 and enrichment factors of 48, 39, 32 and 42 for Cd(2+), Pb(2+), Pd(2+) and Ag(+), respectively, were obtained. The proposed cloud point extraction has been successfully applied for the determination of metal ions in real samples with complicated matrix such as radiology waste, vegetable, blood and urine samples.

  18. Automatic On-line Solid-phase Extraction-Electrothermal Atomic Absorption Spectrometry Exploiting Sequential Injection Analysis for Trace Vanadium, Cadmium and Lead Determination in Human Urine Samples.

    Science.gov (United States)

    Giakisikli, Georgia; Ayala Quezada, Alejandro; Tanaka, Junpei; Anthemidis, Aristidis N; Murakami, Hiroya; Teshima, Norio; Sakai, Tadao

    2015-01-01

    A fully automated sequential injection column preconcentration method for the on-line determination of trace vanadium, cadmium and lead in urine samples was successfully developed, utilizing electrothermal atomic absorption spectrometry (ETAAS). Polyamino-polycarboxylic acid chelating resin (Nobias chelate PA-1) packed into a handmade minicolumn was used as a sorbent material. Effective on-line retention of chelate complexes of analytes was achieved at pH 6.0, while the highest elution effectiveness was observed with 1.0 mol L(-1) HNO3 in the reverse phase. Several analytical parameters, like the sample acidity, concentration and volume of the eluent as well as the loading/elution flow rates, have been studied, regarding the efficiency of the method, providing appropriate conditions for the analysis of real samples. For a 4.5 mL sample volume, the sampling frequency was 27 h(-1). The detection limits were found to be 3.0, 0.06 and 2.0 ng L(-1) for V(V), Cd(II) and Pb(II), respectively, with the relative standard deviations ranging between 1.9 - 3.7%. The accuracy of the proposed method was evaluated by analyzing a certified reference material (Seronorm(TM) trace elements urine) and spiked urine samples.

  19. Development of a flow system for the determination of cadmium in fuel alcohol using vermicompost as biosorbent and flame atomic absorption spectrometry.

    Science.gov (United States)

    Bianchin, Joyce Nunes; Martendal, Edmar; Mior, Renata; Alves, Vanessa Nunes; Araújo, Cleide Sandra Tavares; Coelho, Nívia Maria Melo; Carasek, Eduardo

    2009-04-30

    In this study a method for the determination of cadmium in fuel alcohol using solid-phase extraction with a flow injection analysis system and detection by flame atomic absorption spectrometry was developed. The sorbent material used was a vermicompost commonly used as a garden fertilizer. The chemical and flow variables of the on-line preconcentration system were optimized by means of a full factorial design. The selected factors were: sorbent mass, sample pH, buffer concentration and sample flow rate. The optimum extraction conditions were obtained using sample pH in the range of 7.3-8.3 buffered with tris(hydroxymethyl)aminomethane at 50 mmol L(-1), a sample flow rate of 4.5 mL min(-1) and 160 mg of sorbent mass. With the optimized conditions, the preconcentration factor, limit of detection and sample throughput were estimated as 32 (for preconcentration of 10 mL sample), 1.7 microg L(-1) and 20 samples per hour, respectively. The analytical curve was linear from 5 up to at least 50 microg L(-1), with a correlation coefficient of 0.998 and a relative standard deviation of 2.4% (35 microg L(-1), n=7). The developed method was successfully applied to spiked fuel alcohol, and accuracy was assessed through recovery tests, with recovery ranging from 94% to 100%.

  20. Magnetic stirrer induced dispersive ionic-liquid microextraction for the determination of vanadium in water and food samples prior to graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Naeemullah; Kazi, Tasneem Gul; Tuzen, Mustafa

    2015-04-01

    A new dispersive liquid-liquid microextraction, magnetic stirrer induced dispersive ionic-liquid microextraction (MS-IL-DLLME) was developed to quantify the trace level of vanadium in real water and food samples by graphite furnace atomic absorption spectrometry (GFAAS). In this extraction method magnetic stirrer was applied to obtained a dispersive medium of 1-butyl-3-methylimidazolium hexafluorophosphate [C4MIM][PF6] in aqueous solution of (real water samples and digested food samples) to increase phase transfer ratio, which significantly enhance the recovery of vanadium - 4-(2-pyridylazo) resorcinol (PAR) chelate. Variables having vital role on desired microextraction methods were optimised to obtain the maximum recovery of study analyte. Under the optimised experimental variables, enhancement factor (EF) and limit of detection (LOD) were achieved to be 125 and 18 ng L(-1), respectively. Validity and accuracy of the desired method was checked by analysis of certified reference materials (SLRS-4 Riverine water and NIST SRM 1515 Apple leaves). The relative standard deviation (RSD) for 10 replicate determinations at 0.5 μg L(-1) of vanadium level was found to be food samples.

  1. Supramolecular solvent-based extraction coupled with vortex-mixing for determination of palladium and silver in water samples by flame atomic absorption spectrometry.

    Science.gov (United States)

    Meng, Lifen; Cheng, Jiaxi; Yang, Yaling

    2014-01-01

    A simple and practical extraction method of supramolecular solvents (SUPRAS) was developed for separation and enrichment of trace amounts of palladium (Pd) and silver (Ag) in water samples prior to flame atomic absorption spectrometry (FAAS) analysis. The SUPRAS selected was made up of an aqueous solution containing tetrahydrofuran and nonanoic acid. Pd and Ag reacted with diethyldithiocarbamate to form hydrophobic chelates, which were extracted into the vesicles of SUPRAS. Different parameters such as the concentration of chelating agent, sample pH, supramolecular solvent and the effect of foreign ions were studied. Under the optimal conditions, the linear ranges of Pd and Ag were from 10 to 1,000 μg/L. The relative recoveries of Pd and Ag in tap and river water samples at the spiking level of 10 ug/mL ranged from 90.8 to 116%. The relative standard deviations were 3.6-4.0% (n = 9), the limits of detection were 2.8 and 1.9 μg/L and the enrichment factors were 36 and 18 for Pd and Ag, respectively. The quantification limits were 3.2 and 2.4 μg/L. The method was successfully applied to the determination of Pd and Ag in water samples.

  2. Determination of Lead in Water Samples Using a New Vortex-Assisted, Surfactant-Enhanced Emulsification Liquid-Liquid Microextraction Combined with Graphite Furnace Atomic Absorption Spectrometry.

    Science.gov (United States)

    Peng, Guilong; He, Qiang; Lu, Ying; Mmereki, Daniel; Pan, Weiliang; Tang, Xiaohui; Zhou, Guangming; Mao, Yufeng; Su, Xaioxuan

    2016-04-01

    A low toxic solvent-based vortex-assisted surfactant-enhanced emulsification liquid-liquid microextraction (LT-VSLLME) combined with graphite furnace atomic absorption spectrometry was developed for the extraction and determination of lead (Pb) in water samples. In the LT-VSLLME method, the extraction solvent was dispersed into the aqueous samples by the assistance of vortex agitator. Meanwhile, the addition of a surfactant, which acted as an emulsifier, could enhance the speed of the mass-transfer from aqueous samples to the extraction solvent. The influences of analytical parameters, including extraction solvent type and its volume, surfactant type and its volume, pH, concentration of chelating agent, salt effect and extraction time were investigated. Under the optimized conditions, a good relative standard deviation of 3.69% at 10 ng L(-1) was obtained. The calibration graph showed a linear pattern in the ranges of 5-30 ngL(-1), with a limit of detection of 0.76 ng L(-1). The linearity was obtained by five points in the concentration range of 5-30 ngL(-1). The enrichment factor was 320. The procedure was applied to wastewater and river water, and the accuracy was assessed through the analysis of the recovery experiments.

  3. An analytical method for determination of mercury by cold vapor atomic absorption spectroscopy; Determinazione di mercurio. Metodo per spettrometria di assorbimento atomico a vapori freddi (CV-AAS)

    Energy Technology Data Exchange (ETDEWEB)

    Campanella, L. [Rome Univ. La Sapienza, Rome (Italy); Mastroianni, D.; Capri, S.; Pettine, M. [CNR, Rome (Italy). Ist. di Ricerca sulle Acque; Spezia, S.; Bettinelli, M. [ENEL, Unified Modelling Language, Piacenza (Italy)

    1999-09-01

    An analytical procedure for the determination of total mercury in wastewaters and natural waters is described. Aqueous samples are fast digested with nitric acid by using the microwave-oven technique; the analysis of mercury is then performed by cold vapor atomic absorption spectrometry (CV-AAS) using two possible instrumental apparatus (batch system or flow injection). Sodium borohydride is used as the reducing agent for mercury in solution (Method A). The use of amalgamation traps on gold for the preconcentration of mercury lowers the detection limit of the analyte (Method B). [Italian] Viene descritta una procedura analitica per la determinazione del mercurio totale in acque di scarico e naturali. Il campione acquoso viene sottoposto a mineralizzazione con acido nitrico in forno a microonde e analizzato mediante spettroscopia di assorbimento atomico a vapori freddi (CV-AAS) in due possibili configurazioni strumentali (sistema batch oppure flow injection), utilizzando sodio boro idruro come agente riducente del mercurio (metodo A). L'impiego della trappola di oro per la preconcentrazione del mercurio mediante amalgama consente di determinare l'analita a livelli di pochi ng/L (metodo B).

  4. Rapid determination of zinc and iron in foods by flow-injection analysis with flame atomic-absorption spectrophotometry and slurry nebulization.

    Science.gov (United States)

    de Andrade, J C; Strong, F C; Martin, N J

    1990-07-01

    A rapid method of determining zinc and iron in food by flame atomic-absorption spectrophotometry with slurry nebulization into an air-acetylene flame has been developed. A V-groove, clog-free Babington-type nebulizer, coupled to a single-line flow-injection analysis (FIA) system, was employed to introduce the slurry into the spray chamber. Under the FIA conditions described, an injection frequency of 120/hr is possible, with negligible carry-over and memory effects. The calibration graphs were obtained by using various concentrations (up to 0.1 g/ml) of white bean homogenate as standards, rather than solutions. The method has been applied to various kinds of foods, including grains, vegetables, fruits and sausage. Homogenization of semi-prepared samples to form slurries took only 4 min. Relative deviations between results by the slurry and solution methods for both elements averaged 2-3%. Detection limits by the slurry method were 0.3 mug/ml Zn and 0.6 mug/ml Fe.

  5. Feasibility of using in situ fusion for the determination of Co, Cr and Mn in Portland cement by direct solid sampling graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Intima, Danielle Polidorio; de Oliveira, Elisabeth; Oliveira, Pedro Vitoriano

    2009-06-01

    In situ fusion on the boat-type graphite platform has been used as a sample pretreatment for the direct determination of Co, Cr and Mn in Portland cement by solid sampling graphite furnace atomic absorption spectrometry (SS-GF AAS). The 3-field Zeeman technique was adopted for background correction to decrease the sensitivity during measurements. This strategy allowed working with up to 200 µg of sample. The in situ fusion was accomplished using 10 µL of a flux mixture 4.0% m/v Na 2CO 3 + 4.0% m/v ZnO + 0.1% m/v Triton® X-100 added over the cement sample and heated at 800 °C for 20 s. The resulting mould was completely dissolved with 10 µL of 0.1% m/v HNO 3. Limits of detection were 0.11 µg g - 1 for Co, 1.1 µg g - 1 for Cr and 1.9 µg g - 1 for Mn. The accuracy of the proposed method has been evaluated by the analysis of certified reference materials. The values found presented no statistically significant differences compared to the certified values (Student's t-test, p < 0.05). In general, the relative standard deviation was lower than 12% ( n = 5).

  6. Determination of As(III) and total inorganic As in water samples using an on-line solid phase extraction and flow injection hydride generation atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sigrist, Mirna, E-mail: msigrist@fiq.unl.edu.ar [Laboratorio Central, Facultad de Ingenieria Quimica, Universidad Nacional del Litoral, Santiago del Estero 2654-Piso 6, (3000) Santa Fe (Argentina); Albertengo, Antonela; Beldomenico, Horacio [Laboratorio Central, Facultad de Ingenieria Quimica, Universidad Nacional del Litoral, Santiago del Estero 2654-Piso 6, (3000) Santa Fe (Argentina); Tudino, Mabel [Laboratorio de Analisis de Trazas, Departamento de Quimica Inorganica, Analitica y Quimica Fisica/INQUIMAE, Facultad de Ciencias Exactas y Naturales, Pabellon II, Ciudad Universitaria (1428), Buenos Aires (Argentina)

    2011-04-15

    A simple and robust on-line sequential injection system based on solid phase extraction (SPE) coupled to a flow injection hydride generation atomic absorption spectrometer (FI-HGAAS) with a heated quartz tube atomizer (QTA) was developed and optimized for the determination of As(III) in groundwater without any kind of sample pretreatment. The method was based on the selective retention of inorganic As(V) that was carried out by passing the filtered original sample through a cartridge containing a chloride-form strong anion exchanger. Thus the most toxic form, inorganic As(III), was determined fast and directly by AsH{sub 3} generation using 3.5 mol L{sup -1} HCl as carrier solution and 0.35% (m/v) NaBH{sub 4} in 0.025% NaOH as the reductant. Since the uptake of As(V) should be interfered by several anions of natural occurrence in waters, the effect of Cl{sup -}, SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, HPO{sub 4}{sup 2-}, HCO{sub 3}{sup -} on retention was evaluated and discussed. The total soluble inorganic arsenic concentration was determined on aliquots of filtered samples acidified with concentrated HCl and pre-reduced with 5% KI-5% C{sub 6}H{sub 8}O{sub 6} solution. The concentration of As(V) was calculated by difference between the total soluble inorganic arsenic and As(III) concentrations. Detection limits (LODs) of 0.5 {mu}g L{sup -1} and 0.6 {mu}g L{sup -1} for As(III) and inorganic total As, respectively, were obtained for a 500 {mu}L sample volume. The obtained limits of detection allowed testing the water quality according to the national and international regulations. The analytical recovery for water samples spiked with As(III) ranged between 98% and 106%. The sampling throughput for As(III) determination was 60 samples h{sup -1}. The device for groundwater sampling was especially designed for the authors. Metallic components were avoided and the contact between the sample and the atmospheric oxygen was carried to a minimum. On-field arsenic species

  7. Novel analytical reagent for the application of cloud-point preconcentration and flame atomic absorption spectrometric determination of nickel in natural water samples

    Energy Technology Data Exchange (ETDEWEB)

    Suvardhan, K. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Rekha, D. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Kumar, K. Suresh [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Prasad, P. Reddy [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Kumar, J. Dilip [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Jayaraj, B. [Department of Mathematics, S.V. University, Tirupati 517502, AP (India); Chiranjeevi, P. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India)]. E-mail: chiranjeevipattium@gmail.com

    2007-06-01

    Cloud-point extraction was applied as a preconcentration of nickel after formation of complex with newly synthesized N-quino[8,7-b]azin-5-yl-2,3,5,6,8,9,11,12octahydrobenzo[b][1,4,7,10,13] pentaoxacyclopentadecin-15-yl-methanimine, and later determined by flame atomic absorption spectrometry (FAAS) using octyl phenoxy polyethoxy ethanol (Triton X-114) as surfactant. Nickel was complexed with N-quino[8,7-b]azin-5-yl-2,3,5,6,8,9,11,12 octahydrobenzo[b][1,4,7,10,13]pentaoxacyclopentadecin-15-yl-methanimine in an aqueous phase and was kept for 15 min in a thermo-stated bath at 40 deg. C. Separation of the two phases was accomplished by centrifugation for 15 min at 4000 rpm. The chemical variables affecting the cloud-point extraction were evaluated, optimized and successfully applied to the nickel determination in various water samples. Under the optimized conditions, the preconcentration system of 100 ml sample permitted an enhancement factor of 50-fold. The detailed study of various interferences made the method more selective. The detection limits obtained under optimal condition was 0.042 ng ml{sup -1}. The extraction efficiency was investigated at different nickel concentrations (20-80 ng ml{sup -1}) and good recoveries (99.05-99.93%) were obtained using present method. The proposed method has been applied successfully for the determination of nickel in various water samples and compared with reported method in terms of Student's t-test and variance ratio f-test which indicate the significance of present method over reported and spectrophotometric methods at 95% confidence 0011lev.

  8. Preconcentration and determination of trace silver ion using benzothiazole calix[4]arene modified silica by flow injection flame atomic absorption spectrometry.

    Science.gov (United States)

    Waluvanaruk, Jitwilai; Aeungmaitrepirom, Wanlapa; Tuntulani, Thawatchai; Ngamukot, Passapol

    2014-01-01

    The silica gel modified with benzothiazole calix[4]arene (APS-L1) via Schiff's base reaction was applied as a sorbent in an online system for preconcentration and determination of silver ion by flame atomic absorption spectrometry (FAAS). APS-L1 was used as an effective sorbent for solid phase extraction (SPE) of silver(I) ion in both batch and column methods. The optimum experimental parameters such as pH, eluent type, sample flow rate, eluent volume and eluent flow rate including the effect of interfering ions were investigated. Silver(I) ion was determined at pH 6-7. The capacity of APS-L1 sorbent was found to be 12.2 mg/g of sorbent. The high affinity was obtained without interference from the interfering ions. The optimum conditions of the online flow injection preconcentration coupled with the FAAS (FI-FAAS system) were evaluated. The sample flow rate was 3.0 mL min(-1) using sample volume of 5-10 mL. Elution was performed with 250 μL of 0.1 mol L(-1) thiosulfate at the flow rate of 1.5 mL min(-1). The analytical characteristics and performance of the FI-FAAS system were studied under optimum conditions using a solution spiked with standard silver(I) ion at 20 and 50 μg L(-1). The detection limit of 0.44 μg L(-1) was obtained. The accuracy of the proposed method was evaluated and percentages of recovery at 20 and 50 μg L(-1) were 100.2 and 99.5%, respectively. The percent relative standard deviations (%RSD) at 20 and 50 μg L(-1) were 6.1 and 3.3%, respectively. The developed method was successfully applied to determine trace silver(I) ion in drinking and tap water samples.

  9. A novel solidified floating organic drop microextraction method for preconcentration and determination of copper ions by flow injection flame atomic absorption spectrometry.

    Science.gov (United States)

    Sahin, Ciğdem Arpa; Tokgöz, Ilknur

    2010-05-14

    A rapid, simple and cost effective solidified floating organic drop microextraction (SFODME) and flow injection flame atomic absorption spectrometric determination (FI-FAAS) method for copper was developed. In this method, a free microdrop of 1-undecanol containing 1,5-diphenyl carbazide (DPC) as the complexing agent was transferred to the surface of an aqueous sample including Cu(II) ions, while being agitated by a stirring bar in the bulk of the solution. Under the proper stirring conditions, the suspended microdrop can remain at the top-center position of the aqueous sample. After the completion of the extraction, the sample vial was cooled by placing it in a refrigerator for 10min. The solidified microdrop was then transferred into a conical vial, where it melted immediately and diluted to 300microL with ethanol. Finally, copper ions in 200microL of diluted solution were determined by FI-FAAS. Several factors affecting the microextraction efficiency, such as type of extraction solvent, pH, complexing agent concentration, extraction time, stirring rate, sample volume and temperature were investigated and optimized. Under optimized conditions for 100mL of solution, the preconcentration factor was 333 and the enrichment factor was 324. The limit of detection (3s) was 0.4ngmL(-1), the limit of quantification (10s) was 1.1ngmL(-1) and the relative standard deviation (RSD) for 10 replicate measurements of 10ngmL(-1) copper was 0.9%. The proposed method was successfully applied to the determination of copper in different water samples.

  10. Development of an analytical method for the determination of arsenic in gasoline samples by hydride generation-graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Emilene M. [Universidade Federal do Pampa, Bage, RS (Brazil); Universidade Federal de Pelotas, Pelotas, RS (Brazil); Dessuy, Morgana B.; Boschetti, Wiliam [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil); Vale, Maria Goreti R., E-mail: mgrvale@ufrgs.br [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Ferreira, Sergio L.C. [Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Instituto de Quimica, Universidade Federal da Bahia, Salvador, BA (Brazil); Welz, Bernhard [Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900 Florianopolis, SC (Brazil)

    2012-05-15

    The purpose of the present work was to optimize the conditions for the determination of arsenic in gasoline with hydride generation-graphite furnace atomic absorption spectrometry after acid digestion using a full two-level factorial design with center point. The arsine was generated in a batch system and collected in a graphite tube coated with 150 {mu}g Ir as a permanent modifier. The sample volume, the pre-reduction conditions, the temperature program and modifier mass were kept fixed for all experiments. The estimated main effects were: reducing agent concentration (negative effect), acid concentration (negative effect) and trapping temperature (positive effect). It was observed that there were interactions between the variables. Moreover, the curvature was significant, indicating that the best conditions were at the center point. The optimized parameters for arsine generation were 2.7 mol L{sup -1} hydrochloric acid and 1.6% (w/v) sodium tetrahydroborate. The optimized conditions to collect arsine in the graphite furnace were a trapping temperature of 250 Degree-Sign C and a collection time of 30 s. The limit of detection was 6.4 ng L{sup -1} and the characteristic mass was 24 pg. Two different systems for acid digestion were used: a digester block with cold finger and a microwave oven. The concentration of arsenic found with the proposed method was compared with that obtained using a detergentless microemulsion and direct graphite furnace determination. The results showed that the factorial design is a simple tool that allowed establishing the appropriate conditions for sample preparation and also helped in evaluating the interaction between the factors investigated. - Highlights: Black-Right-Pointing-Pointer We determined As in gasoline using hydride generation-graphite furnace AAS. Black-Right-Pointing-Pointer We compared three sample preparation procedures. Black-Right-Pointing-Pointer A multivariate approach was used to optimize the conditions. Black

  11. Precision atomic beam density characterization by diode laser absorption spectroscopy

    Science.gov (United States)

    Oxley, Paul; Wihbey, Joseph

    2016-09-01

    We provide experimental and theoretical details of a simple technique to determine absolute line-of-sight integrated atomic beam densities based on resonant laser absorption. In our experiments, a thermal lithium beam is chopped on and off while the frequency of a laser crossing the beam at right angles is scanned slowly across the resonance transition. A lock-in amplifier detects the laser absorption signal at the chop frequency from which the atomic density is determined. The accuracy of our experimental method is confirmed using the related technique of wavelength modulation spectroscopy. For beams which absorb of order 1% of the incident laser light, our measurements allow the beam density to be determined to an accuracy better than 5% and with a precision of 3% on a time scale of order 1 s. Fractional absorptions of order 10-5 are detectable on a one-minute time scale when we employ a double laser beam technique which limits laser intensity noise. For a lithium beam with a thickness of 9 mm, we have measured atomic densities as low as 5 × 104 atoms cm-3. The simplicity of our technique and the details we provide should allow our method to be easily implemented in most atomic or molecular beam apparatuses.

  12. Determination of lead in blood by chelation with ammonium pyrrolidine dithio-carbamate followed by tungsten-coil atomic absorption spectrometry

    Science.gov (United States)

    Salido, Arthur; Sanford, Caryn L.; Jones, Bradley T.

    1999-08-01

    An inexpensive, bench-top blood Pb analyzer has been developed. The system is based on tungsten-coil atomic absorption spectrometry. Pb atomization occurs on W-coils extracted from commercially available slide projector bulbs. The system has minimal power requirements: 120 ACV and 15 A. A small, computer-controlled CCD spectrometer is used as the detector. A Pb hollow cathode lamp is used as the source. Blood Pb is chelated with ammonium pyrrolidine dithio-carbamate and extracted into methyl iso-butyl ketone (4-methyl 2-pentanone). Twenty-microliter volumes of the organic phase are deposited on the W-coil, dried at 1.4 A, charred at 2.3 A and atomized at 6.0 A. Graphite furnace atomic absorption spectrometry is used as a comparison for W-coil results. Levels 1-4 of a NIST standard reference material 955b ‘lead in bovine blood’ are used to test accuracy and precision. The analytical figures of merit for the system are: 12-pg instrument detection limit, 24-pg blood detection limit and a characteristic mass of 28 pg.

  13. Preconcentration and determination of vanadium and molybdenum in milk, vegetables and foodstuffs by ultrasonic-thermostatic-assisted cloud point extraction coupled to flame atomic absorption spectrometry.

    Science.gov (United States)

    Gürkan, Ramazan; Korkmaz, Sema; Altunay, Nail

    2016-08-01

    A new ultrasonic-thermostatic-assisted cloud point extraction procedure (UTA-CPE) was developed for preconcentration at the trace levels of vanadium (V) and molybdenum (Mo) in milk, vegetables and foodstuffs prior to determination via flame atomic absorption spectrometry (FAAS). The method is based on the ion-association of stable anionic oxalate complexes of V(V) and Mo(VI) with [9-(diethylamino)benzo[a]phenoxazin-5-ylidene]azanium; sulfate (Nile blue A) at pH 4.5, and then extraction of the formed ion-association complexes into micellar phase of polyoxyethylene(7.5)nonylphenyl ether (PONPE 7.5). The UTA-CPE is greatly simplified and accelerated compared to traditional cloud point extraction (CPE). The analytical parameters optimized are solution pH, the concentrations of complexing reagents (oxalate and Nile blue A), the PONPE 7.5 concentration, electrolyte concentration, sample volume, temperature and ultrasonic power. Under the optimum conditions, the calibration curves for Mo(VI) and V(V) are obtained in the concentration range of 3-340µgL(-1) and 5-250µgL(-1) with high sensitivity enhancement factors (EFs) of 145 and 115, respectively. The limits of detection (LODs) for Mo(VI) and V(V) are 0.86 and 1.55µgL(-1), respectively. The proposed method demonstrated good performances such as relative standard deviations (as RSD %) (≤3.5%) and spiked recoveries (95.7-102.3%). The accuracy of the method was assessed by analysis of two standard reference materials (SRMs) and recoveries of spiked solutions. The method was successfully applied into the determination of trace amounts of Mo(VI) and V(V) in milk, vegetables and foodstuffs with satisfactory results.

  14. Multiple response optimization for Cu, Fe and Pb determination in naphtha by graphite furnace atomic absorption spectrometry with sample injection as detergent emulsion

    Science.gov (United States)

    Brum, Daniel M.; Lima, Claudio F.; Robaina, Nicolle F.; Fonseca, Teresa Cristina O.; Cassella, Ricardo J.

    2011-05-01

    The present paper reports the optimization for Cu, Fe and Pb determination in naphtha by graphite furnace atomic absorption spectrometry (GF AAS) employing a strategy based on the injection of the samples as detergent emulsions. The method was optimized in relation to the experimental conditions for the emulsion formation and taking into account that the three analytes (Cu, Fe and Pb) should be measured in the same emulsion. The optimization was performed in a multivariate way by employing a three-variable Doehlert design and a multiple response strategy. For this purpose, the individual responses of the three analytes were combined, yielding a global response that was employed as a dependent variable. The three factors related to the optimization process were: the concentration of HNO 3, the concentration of the emulsifier agent (Triton X-100 or Triton X-114) in aqueous solution used to emulsify the sample and the volume of solution. At optimum conditions, it was possible to obtain satisfactory results with an emulsion formed by mixing 4 mL of the samples with 1 mL of a 4.7% w/v Triton X-100 solution prepared in 10% v/v HNO 3 medium. The resulting emulsion was stable for 250 min, at least, and provided enough sensitivity to determine the three analytes in the five samples tested. A recovery test was performed to evaluate the accuracy of the optimized procedure and recovery rates, in the range of 88-105%; 94-118% and 95-120%, were verified for Cu, Fe and Pb, respectively.

  15. Multiple response optimization for Cu, Fe and Pb determination in naphtha by graphite furnace atomic absorption spectrometry with sample injection as detergent emulsion

    Energy Technology Data Exchange (ETDEWEB)

    Brum, Daniel M.; Lima, Claudio F. [Departamento de Quimica, Universidade Federal de Vicosa, A. Peter Henry Rolfs s/n, Vicosa/MG, 36570-000 (Brazil); Robaina, Nicolle F. [Departamento de Quimica Analitica, Universidade Federal Fluminense, Outeiro de S.J. Batista s/n, Centro, Niteroi/RJ, 24020-141 (Brazil); Fonseca, Teresa Cristina O. [Petrobras, Cenpes/PDEDS/QM, Av. Horacio Macedo 950, Ilha do Fundao, Rio de Janeiro/RJ, 21941-915 (Brazil); Cassella, Ricardo J., E-mail: cassella@vm.uff.br [Departamento de Quimica Analitica, Universidade Federal Fluminense, Outeiro de S.J. Batista s/n, Centro, Niteroi/RJ, 24020-141 (Brazil)

    2011-05-15

    The present paper reports the optimization for Cu, Fe and Pb determination in naphtha by graphite furnace atomic absorption spectrometry (GF AAS) employing a strategy based on the injection of the samples as detergent emulsions. The method was optimized in relation to the experimental conditions for the emulsion formation and taking into account that the three analytes (Cu, Fe and Pb) should be measured in the same emulsion. The optimization was performed in a multivariate way by employing a three-variable Doehlert design and a multiple response strategy. For this purpose, the individual responses of the three analytes were combined, yielding a global response that was employed as a dependent variable. The three factors related to the optimization process were: the concentration of HNO{sub 3}, the concentration of the emulsifier agent (Triton X-100 or Triton X-114) in aqueous solution used to emulsify the sample and the volume of solution. At optimum conditions, it was possible to obtain satisfactory results with an emulsion formed by mixing 4 mL of the samples with 1 mL of a 4.7% w/v Triton X-100 solution prepared in 10% v/v HNO{sub 3} medium. The resulting emulsion was stable for 250 min, at least, and provided enough sensitivity to determine the three analytes in the five samples tested. A recovery test was performed to evaluate the accuracy of the optimized procedure and recovery rates, in the range of 88-105%; 94-118% and 95-120%, were verified for Cu, Fe and Pb, respectively.

  16. Ionic liquid-based ultrasound-assisted dispersive liquid-liquid microextraction combined with electrothermal atomic absorption spectrometry for a sensitive determination of cadmium in water samples

    Energy Technology Data Exchange (ETDEWEB)

    Li Shengqing [Department of Chemistry, College of Science, Huazhong Agricultural University, Wuhan 430070 (China); Supervision, Inspection and Testing Center of Microbial Products Quality (Wuhan), Ministry of Agriculture (China)], E-mail: sqingli@mail.hzau.edu.cn; Cai Shun; Hu Wei [Department of Chemistry, College of Science, Huazhong Agricultural University, Wuhan 430070 (China); Chen Hao [Department of Chemistry, College of Science, Huazhong Agricultural University, Wuhan 430070 (China)], E-mail: hchenhao@mail.hzau.edu.cn; Liu Hanlan [Department of Chemistry, College of Science, Huazhong Agricultural University, Wuhan 430070 (China)

    2009-07-15

    A new method was developed for the determination of cadmium in water samples using ionic liquid-based ultrasound-assisted dispersive liquid-liquid microextraction (IL-based USA-DLLME) followed by electrothermal atomic absorption spectrometry (ETAAS). The IL-based USA-DLLME procedure is free of volatile organic solvents, and there is no need for a dispersive solvent, in contrast to conventional DLLME. The ionic liquid, 1-hexyl-3-methylimidazolium hexafluorophosphate (HMIMPF{sub 6}), was quickly disrupted by an ultrasonic probe for 1 min and dispersed in water samples like a cloud. At this stage, a hydrophobic cadmium-DDTC complex was formed and extracted into the fine droplets of HMIMPF{sub 6}. After centrifugation, the concentration of the enriched cadmium in the sedimented phase was determined by ETAAS. Some effective parameters of the complex formation and microextraction, such as the concentration of the chelating agent, the pH, the volume of the extraction solvent, the extraction time, and the salt effect, have been optimized. Under optimal conditions, a high extraction efficiency and selectivity were reached for the extraction of 1.0 ng of cadmium in 10.0 mL of water solution employing 73 {mu}L of HMIMPF{sub 6} as the extraction solvent. The enrichment factor of the method is 67. The detection limit was 7.4 ng L{sup - 1}, and the characteristic mass (m{sub 0}, 0.0044 absorbance) of the proposed method was 0.02 pg for cadmium (Cd). The relative standard deviation (RSD) for 11 replicates of 50 ng L{sup - 1} Cd was 3.3%. The method was applied to the analysis of tap, well, river, and lake water samples and the Environmental Water Reference Material GSBZ 50009-88 (200921). The recoveries of spiked samples were in the range of 87.2-106%.

  17. Ionic liquid-based ultrasound-assisted dispersive liquid-liquid microextraction combined with electrothermal atomic absorption spectrometry for a sensitive determination of cadmium in water samples

    Science.gov (United States)

    Li, Shengqing; Cai, Shun; Hu, Wei; Chen, Hao; Liu, Hanlan

    2009-07-01

    A new method was developed for the determination of cadmium in water samples using ionic liquid-based ultrasound-assisted dispersive liquid-liquid microextraction (IL-based USA-DLLME) followed by electrothermal atomic absorption spectrometry (ETAAS). The IL-based USA-DLLME procedure is free of volatile organic solvents, and there is no need for a dispersive solvent, in contrast to conventional DLLME. The ionic liquid, 1-hexyl-3-methylimidazolium hexafluorophosphate (HMIMPF 6), was quickly disrupted by an ultrasonic probe for 1 min and dispersed in water samples like a cloud. At this stage, a hydrophobic cadmium-DDTC complex was formed and extracted into the fine droplets of HMIMPF 6. After centrifugation, the concentration of the enriched cadmium in the sedimented phase was determined by ETAAS. Some effective parameters of the complex formation and microextraction, such as the concentration of the chelating agent, the pH, the volume of the extraction solvent, the extraction time, and the salt effect, have been optimized. Under optimal conditions, a high extraction efficiency and selectivity were reached for the extraction of 1.0 ng of cadmium in 10.0 mL of water solution employing 73 µL of HMIMPF 6 as the extraction solvent. The enrichment factor of the method is 67. The detection limit was 7.4 ng L - 1 , and the characteristic mass ( m0, 0.0044 absorbance) of the proposed method was 0.02 pg for cadmium (Cd). The relative standard deviation (RSD) for 11 replicates of 50 ng L - 1 Cd was 3.3%. The method was applied to the analysis of tap, well, river, and lake water samples and the Environmental Water Reference Material GSBZ 50009-88 (200921). The recoveries of spiked samples were in the range of 87.2-106%.

  18. Selective determination of inorganic cobalt in nutritional supplements by ultrasound-assisted temperature-controlled ionic liquid dispersive liquid phase microextraction and electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Berton, Paula; Martinis, Estefania M. [Analytical Chemistry Research and Development Group (QUIANID), (LISAMEN-CCT-CONICET-Mendoza), Av. Ruiz Leal S/N Parque General San Martin, M 5502 IRA Mendoza (Argentina); Martinez, Luis D. [INQUISAL-CONICET, Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, San Luis (Argentina); Wuilloud, Rodolfo G., E-mail: rwuilloud@mendoza-conicet.gob.ar [Analytical Chemistry Research and Development Group (QUIANID), (LISAMEN-CCT-CONICET-Mendoza), Av. Ruiz Leal S/N Parque General San Martin, M 5502 IRA Mendoza (Argentina); Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza (Argentina)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer Synergy of ultrasound energy and TILDLME technique for improved metal extraction. Black-Right-Pointing-Pointer Highly selective determination of inorganic Co species at trace levels. Black-Right-Pointing-Pointer Speciation analysis of Co in several nutritional supplements with highly complex matrices. Black-Right-Pointing-Pointer Development of an environmentally friendly microextraction technique with minimal waste production and sample consumption. - Abstract: In the present work, a simple and rapid analytical method based on application of ionic liquids (ILs) for inorganic Co(II) species (iCo) microextraction in a variety of nutrient supplements was developed. Inorganic Co was initially chelated with 1-nitroso-2-naphtol (1N2N) reagent followed by a modern technique named ultrasound-assisted temperature-controlled ionic liquid dispersive liquid phase microextraction (USA-TILDLME). The extraction was performed with 1-hexyl-3-methylimidazolium hexafluorophosphate [C{sub 6}mim][PF{sub 6}] with the aid of ultrasound to improve iCo recovery. Finally, the iCo-enriched IL phase was solubilized in methanol and directly injected into an electrothermal atomic absorption spectrometer (ETAAS). Several parameters that could influence iCo microextraction and detection were carefully studied. Since the main difficulty in these samples is caused by high concentrations of potential interfering ions, different approaches were evaluated to eliminate interferences. The limit of detection (LOD) was 5.4 ng L{sup -1}, while the relative standard deviation (RSD) was 4.7% (at 0.5 {mu}g L{sup -1} Co level and n = 10), calculated from the peak height of absorbance signals. Selective microextraction of iCo species was achieved only by controlling the pH value during the procedure. The method was thus successfully applied for determination of iCo species in nutritional supplements.

  19. Determination of tellurium at ultra-trace levels in drinking water by on-line solid phase extraction coupled to graphite furnace atomic absorption spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Pedro, Juana [Area de Quimica Analitica, Departamento de Quimica, Facultad de Ingenieria Quimica, Universidad Nacional del Litoral, Santiago del Estero 2829 (S3000GL.N), Santa Fe (Argentina); Stripekis, Jorge [Laboratorio de Analisis de Trazas, Departamento de Quimica Inorganica, Analitica y Quimica Fisica, INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (1428), Buenos Aires (Argentina); Bonivardi, Adrian [Area de Quimica Analitica, Departamento de Quimica, Facultad de Ingenieria Quimica, Universidad Nacional del Litoral, Santiago del Estero 2829 (S3000GL.N), Santa Fe (Argentina); Tudino, Mabel [Laboratorio de Analisis de Trazas, Departamento de Quimica Inorganica, Analitica y Quimica Fisica, INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (1428), Buenos Aires (Argentina)], E-mail: tudino@qi.fcen.uba.ar

    2008-01-15

    In this paper, two time-based flow injection (FI) separation pre-concentration systems coupled to graphite furnace atomic absorption spectrometry (GFAAS) for tellurium determination are studied and compared. The first alternative involves the pre-concentration of the analyte onto Dowex 1X8 employed as packaging material of a micro-column inserted in the flow system. The second set-up is based on the co-precipitation of tellurium with La(OH){sub 3} followed by retention onto XAD resins. Both systems are compared in terms of limit of detection, linear range, RSD%, sample throughput, micro-columns lifetime and aptitude for fully automatic operation. The features of the Dowex system are: 37% efficiency of retention and an enhancement factor of 42 for a pre-concentration time of 180 seconds (sample flow rate = 3 ml min{sup -1}) with acetic acid elution volumes of 80 {mu}l. The detection limit (3 s) is 7 ng l{sup -1} and the relative standard deviation (n = 7200 ng l{sup -1}) is 5.8%. The analytical performance of the XAD system is: 72% efficiency of retention and an enhancement factor of 25 for a pre-concentration time of 180 s (sample flow rate = 3 ml min{sup -1}) with nitric acid elution volumes of 300 {mu}l. The detection limit is 66 ng l{sup -1} and the relative standard deviation (n = 7200 ng l{sup -1}) is 8.3%. Applications to the determination of tellurium in tap water and the validation of the analytical methodology employing SRM 1643e as certified reference material are shown.

  20. Simultaneous determination of antimony and boron in beverage and dairy products by flame atomic absorption spectrometry after separation and pre-concentration by cloud-point extraction.

    Science.gov (United States)

    Altunay, Nail; Gürkan, Ramazan

    2016-01-01

    A new cloud-point extraction (CPE) method was developed for the pre-concentration and simultaneous determination of Sb(III) and B(III) by flame atomic absorption spectrometry (FAAS). The method was based on complexation of Sb(III) and B(III) with azomethine-H in the presence of cetylpyridinium chloride (CPC) as a signal-enhancing agent, and then extraction into the micellar phase of Triton X-114. Under optimised conditions, linear calibration was obtained for Sb(III) and B(III) in the concentration ranges of 0.5-180 and 2.5-600 μg l(-1) with LODs of 0.15 and 0.75 μg l(-1), respectively. Relative standard deviations (RSDs) (25 and 100 μg l(-1) of Sb(III) and B(III), n = 6) were in a range of 2.1-3.8% and 1.9-2.3%, respectively. Recoveries of spiked samples of Sb(III) and B(III) were in the range of 98-103% and 99-102%, respectively. Measured values for Sb and B in three standard reference materials were within the 95% confidence limit of the certified values. Also, the method was used for the speciation of inorganic antimony. Sb(III), Sb(V) and total Sb were measured in the presence of excess boron before and after pre-reduction with an acidic mixture of KI-ascorbic acid. The method was successfully applied to the simultaneous determination of total Sb and B in selected beverage and dairy products.

  1. Preparation of modified magnetic nanoparticles as a sorbent for the preconcentration and determination of cadmium ions in food and environmental water samples prior to flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mirabi, Ali; Dalirandeh, Zeinab [Department of Chemistry, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of); Rad, Ali Shokuhi, E-mail: a.shokuhi@qaemshahriau.ac.ir [Department of Chemical Engineering, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of)

    2015-05-01

    A new method has been developed for the separation/preconcentration of trace level cadmium ions using diphenyl carbazone/sodium dodecyl sulfate immobilized on magnetic nanoparticle Fe{sub 3}O{sub 4} as a new sorbent SPE and their determination by flame atomic absorption spectrometry (FAAS). Synthesized nanoparticle was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). Various influencing parameters on the separation and preconcentration of trace level cadmium ions such as, pH value, amount of nanoparticles, amount of diphenyl carbazone, condition of eluting solution, the effects of matrix ions were examined. The cadmium ions can be eluted from the modified magnetic nanoparticle using 1 mol L{sup −1} HCl as a desorption reagent. The detection limit of this method for cadmium was 3.71 ng ml{sup −1} and the R.S.D. was 0.503% (n=6). The advantages of this new method include rapidity, easy preparation of sorbents and a high concentration factor. The proposed method has been applied to the determination of Cd ions at trace levels in real samples such as, green tea, rice, tobacco, carrot, lettuce, ginseng, spice, tap water, river water, sea water with satisfactory results. - Highlights: • MNPs method is economical, simple, rapid and sensitive for trace analysis of Cd. • High preconcentration factor was obtained easily through this method. • A detection limit at ng mL{sup −1} level was achieved with 100.0 mL of sample. • This method provides good repeatability and extraction efficiency in a short time.

  2. Method development for the determination of cadmium in fertilizer samples using high-resolution continuum source graphite furnace atomic absorption spectrometry and slurry sampling

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Aline R. [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq-INCT de Energia e Ambiente, Universidade Federal de Bahia, Salvador, BA (Brazil); Becker, Emilene M. [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Lequeux, Celine [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Universite de Rennes 1, Rennes (France); Vale, Maria Goreti R., E-mail: mgrvale@ufrgs.br [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq-INCT de Energia e Ambiente, Universidade Federal de Bahia, Salvador, BA (Brazil); Ferreira, Sergio L.C. [Instituto Nacional de Ciencia e Tecnologia do CNPq-INCT de Energia e Ambiente, Universidade Federal de Bahia, Salvador, BA (Brazil); Instituto de Quimica, Universidade Federal da Bahia, Salvador, Bahia 40170-290 (Brazil); Welz, Bernhard [Instituto Nacional de Ciencia e Tecnologia do CNPq-INCT de Energia e Ambiente, Universidade Federal de Bahia, Salvador, BA (Brazil); Departamento de Quimica, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil)

    2011-07-15

    The determination of cadmium (Cd) in fertilizers is of major interest, as this element can cause growth problems in plants, and also affect animals and humans. High-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) with charge-coupled device (CCD) array detection overcomes several of the limitations encountered with conventional line source AAS, especially the problem of accurate background measurement and correction. In this work an analytical method has been developed to determine Cd in fertilizer samples by HR-CS GF AAS using slurry sampling. Both a mixture of 10 {mu}g Pd + 6 {mu}g Mg in solution and 400 {mu}g of iridium as permanent modifier have been investigated and aqueous standards were used for calibration. Pyrolysis and atomization temperatures were 600 {sup o}C and 1600 {sup o}C for the Pd-Mg modifier, and 500 deg. C and 1600 deg. C for Ir, respectively. The results obtained for Cd in the certified reference material NIST SRM 695 (Trace Elements in Multi-Nutrient Fertilizer) of 16.7 {+-} 1.3 {mu}g g{sup -1} and 16.4 {+-} 0.75 {mu}g g{sup -1} for the Pd-Mg and Ir modifier, respectively, were statistically not different from the certified value of 16.9 {+-} 0.2 {mu}g g{sup -1} on a 95% confidence level; however, the results obtained with the Ir modifier were significantly lower than those for the Pd-Mg modifier for most of the samples. The characteristic mass was 1.0 pg for the Pd-Mg modifier and 1.1 pg Cd for the Ir modifier, and the correlation coefficients (R{sup 2}) of the calibration were > 0.99. The instrumental limits of detection were 7.5 and 7.9 ng g{sup -1}, and the limits of quantification were 25 and 27 ng g{sup -1} for Pd-Mg and Ir, respectively, based on a sample mass of 5 mg. The cadmium concentration in the investigated samples was between 0.07 and 5.5 {mu}g g{sup -1} Cd, and hence below the maximum value of 20 {mu}g g{sup -1} Cd permitted by Brazilian legislation.

  3. [Study on Content Determination of Lead and Arsenic in Four Traditional Tibetan Medicine Prescription Preparations by Wet Digestion Flow Injection-Hydride Generation-Atomic Absorption Spectrometry].

    Science.gov (United States)

    Zheng, Zhi-yuan; Du, Yu-zhi; Zhang, Ming; Yu, Ming-jie; Li, Cen; Yang, Hong-xia; Zhao, Jing; Xia, Zheng-hua; Wei, Li-xin

    2015-04-01

    Four common traditional tibetan medicine prescription preparations "Anzhijinghuasan, Dangzuo, Renqingchangjue and Rannasangpei" in tibetan areas were selected as study objects in the present study. The purpose was to try to establish a kind of wet digestion and flow injection-hydride generation-atomic absorption spectrometry (FI-HAAS) associated analysis method for the content determinations of lead and arsenic in traditional tibetan medicine under optimized digestion and measurement conditions and determine their contents accurately. Under these optimum operating conditions, experimental results were as follows. The detection limits for lead and arsenic were 0.067 and 0.012 µg · mL(-1) respectively. The quantification limits for lead and arsenic were 0.22 and 0.041 µg · mL(-1) respectively. The linear ranges for lead and arsenic were 25-1,600 ng · mL(-1) (r = 0.9995) and 12.5-800 ng · mL(-1) (r = 0.9994) respectively. The degrees of precision(RSD) for lead and arsenic were 2.0% and 3.2% respectively. The recovery rates for lead and arsenic were 98.00%-99.98% and 96.67%-99.87% respectively. The content determination results of lead and arsenic in four traditional tibetan medicine prescription preparations were as fol- lows. The contents of lead and arsenic in Anzhijinghuasan are 0.63-0.67 µg · g(-1) and 0.32-0.33 µg · g(-1) in Anzhijinghua- san, 42.92-43.36 µg · g(-1) and 24.67-25.87 µg · g(-1) in Dangzuo, 1,611. 39-1,631.36 µg · g(-1) and 926.76-956.52 µg- g(-1) in Renqing Changjue, and 1,102.28-1,119.127 µg-g(-1) and 509.96-516.87 µg · g(-1) in Rannasangpei, respectively. This study established a method for content determination of lead and arsenic in traditional tibetan medicine, and determined the content levels of lead and arsenic in four tibetan medicine-prescription preparations accurately. In addition, these results also provide the basis for the safe and effective use of those medicines in clinic.

  4. Study on Determination of copper ores by atomic absorption spectrometry%原子吸收光谱分析测定铜矿石成分探讨

    Institute of Scientific and Technical Information of China (English)

    廖淑珍

    2016-01-01

    In 1950s,China began to use atomic spectroscopy to analyze various elements,such as metallurgy, geology and machinery and other industries.With the development of the atomic spectrum analysis technology,a lot of new analytical techniques are derived. At present,the combination of atomic absorption spectrometry and atomic fluorescence spectrometry has become the main means of atomic spectrum analysis in China. In this paper,we study the chemical analysis of silver,copper,zinc and other elements in the samples of the mine.%20世纪50年代,我国开始应用原子光谱对各种元素进行分析,诸如,冶金、地质和机械等行业.随着原子光谱分析技术的不断发展,衍生出很多新的分析技术,使样品元素的研究更加清晰.目前,原子吸收和原子荧光光谱分析的结合,成为我国原子光谱分析的主要手段.本文以此为切入点,研究矿山样品中的银、铜、锌等元素的化学分析.

  5. Cloud point extraction for determination of lead in blood samples of children, using different ligands prior to analysis by flame atomic absorption spectrometry: A multivariate study

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Faheem, E-mail: shah_ceac@yahoo.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Kazi, Tasneem Gul, E-mail: tgkazi@yahoo.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Afridi, Hassan Imran, E-mail: hassanimranafridi@yahoo.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Naeemullah, E-mail: khannaeemullah@ymail.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Arain, Muhammad Balal, E-mail: bilal_ku2004@yahoo.com [Department of Chemistry, University of Science and Technology, Bannu, KPK (Pakistan); Baig, Jameel Ahmed, E-mail: jab_mughal@yahoo.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)

    2011-09-15

    Highlights: {yields} Trace levels of lead in blood samples of healthy children and with different kidney disorders {yields} Pre-concentration of Pb{sup +2} in acid digested blood samples after chelating with two complexing reagents. {yields} Multivariate technique was used for screening of significant factors that influence the CPE of Pb{sup +2} {yields} The level of Pb{sup +2} in diseased children was significantly higher than referents of same age group. - Abstract: The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of lead (Pb{sup 2+}) from digested blood samples after simultaneous complexation with ammonium pyrrolidinedithiocarbamate (APDC) and diethyldithiocarbamate (DDTC) separately. The complexed analyte was quantitatively extracted with octylphenoxypolyethoxyethanol (Triton X-114). The multivariate strategy was applied to estimate the optimum values of experimental factors. Acidic ethanol was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometer (FAAS). The detection limit value of Pb{sup 2+} for the preconcentration of 10 mL of acid digested blood sample was 1.14 {mu}g L{sup -1}. The accuracy of the proposed methods was assessed by analyzing certified reference material (whole blood). Under the optimized conditions of both CPE methods, 10 mL of Pb{sup 2+} standards (10 {mu}g L{sup -1}) complexed with APDC and DDTC, permitted the enhancement factors of 56 and 42, respectively. The proposed method was used for determination of Pb{sup 2+} in blood samples of children with kidney disorders and healthy controls.

  6. Activated carbon-modified knotted reactor coupled to electrothermal atomic absorption spectrometry for sensitive determination of arsenic species in medicinal herbs and tea infusions

    Energy Technology Data Exchange (ETDEWEB)

    Grijalba, Alexander Castro; Martinis, Estefanía M. [Laboratory of Analytical Chemistry for Research and Development (QUIANID), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Padre J. Contreras 1300, (5500) Mendoza (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires (Argentina); Lascalea, Gustavo E. [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires (Argentina); Wuilloud, Rodolfo G., E-mail: rwuilloud@mendoza-conicet.gob.ar [Laboratory of Analytical Chemistry for Research and Development (QUIANID), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Padre J. Contreras 1300, (5500) Mendoza (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires (Argentina)

    2015-01-01

    A flow injection system based on a modified polytetrafluoroethylene (PTFE) knotted reactor (KR) was developed for arsenite [As(III)] and arsenate [As(V)] species preconcentration and determination by electrothermal atomic absorption spectrometry (ETAAS). Activated carbon (AC) was immobilized on the inner walls of a PTFE KR by a thermal treatment. A significant increase in analyte retention was obtained with the AC-modified KR (100%) as compared to the regular PTFE KR (25%). The preconcentration method involved the on-line formation of As(III)-ammonium pyrrolidinedithiocarbamate (As-APDC) complex, followed by its adsorption onto the inner walls of the AC-modified KR. After analyte retention, the complex was eluted with acetone directly into the graphite furnace of ETAAS. The parameters affecting the flow injection system were evaluated with a full central composite face centered design with three center points. Under optimum conditions, a preconcentration factor of 200 was obtained with 10 ml of sample. The detection limit was 4 ng L{sup −1} and the relative standard deviation (RSD) for six replicate measurements at 0.2 μg L{sup −1} of As were 4.3% and 4.7% for As(III) and As(V), respectively. The developed methodology was highly selective towards As(III), while As(V), monomethylarsonic acid [MMA(V)] and dimethylarsinic [DMA(V)] were not retained in the AC-modified KR. The proposed method was successfully applied for As speciation analysis in infusions originated from medicinal herbs and tea. - Highlights: • We report an efficient method for As speciation. • We have modified a knotted reactor with activated carbon for high sorption capacity. • We provide a simple procedure for surface modification of a PTFE knotted reactor. • We have selectively separated inorganic As species from complex matrix samples. • We have implemented a modified KR in a flow injection system coupled to ETAAS.

  7. Suspended nanoparticles in surfactant media as a microextraction technique for simultaneous separation and preconcentration of cobalt, nickel and copper ions for electrothermal atomic absorption spectrometry determination.

    Science.gov (United States)

    Dadfarnia, Shayessteh; Shakerian, Farid; Shabani, Ali Mohammad Haji

    2013-03-15

    The aim of this study was to describe a new method of microextraction based on the suspension of alumina nanoparticles in the surfactant media for simultaneous separation and preconcentration of the ultra-traces of cobalt, nickel and copper ions. In this technique, the alumina nanoparticles were suspended in the non-ionic surfactant solution of Triton X-114. The analytes in the sample solution were adsorbed onto the nanoparticles. After the phase separation based on the cloud point of the mixture at 40 °C, the nanoparticles settled down in the surfactant rich phase. Then 120 μL of nitric acid (3.0 mol L(-1)) was added to the surfactant rich phase which caused desorption of the analytes. Finally, the liquid phase was separated by centrifugation from the nanoparticles and was used for the quantification of the analytes by the electrothermal atomic absorption spectrometry (ETAAS). The parameters affecting the extraction and detection processes were optimized. Under the optimized experimental conditions (i.e. pH∼8, Triton X-114, 0.05% (v/v); temperature 40 °C), a sample volume of 25 mL resulted in the enhancement factors of 198, 205 and 206 and detection limits (defined as 3Sb/m) of 2.5, 2.8 and 2.6 ng L(-1) for Co(II), Ni(II) and Cu(II) respectively. The sorbent showed high capacity for these metal ions (30-40 mg g(-1) sorbent). The method was successfully applied to the determination of the analytes in natural water samples.

  8. Activated carbon-modified knotted reactor coupled to electrothermal atomic absorption spectrometry for sensitive determination of arsenic species in medicinal herbs and tea infusions

    Science.gov (United States)

    Grijalba, Alexander Castro; Martinis, Estefanía M.; Lascalea, Gustavo E.; Wuilloud, Rodolfo G.

    2015-01-01

    A flow injection system based on a modified polytetrafluoroethylene (PTFE) knotted reactor (KR) was developed for arsenite [As(III)] and arsenate [As(V)] species preconcentration and determination by electrothermal atomic absorption spectrometry (ETAAS). Activated carbon (AC) was immobilized on the inner walls of a PTFE KR by a thermal treatment. A significant increase in analyte retention was obtained with the AC-modified KR (100%) as compared to the regular PTFE KR (25%). The preconcentration method involved the on-line formation of As(III)-ammonium pyrrolidinedithiocarbamate (As-APDC) complex, followed by its adsorption onto the inner walls of the AC-modified KR. After analyte retention, the complex was eluted with acetone directly into the graphite furnace of ETAAS. The parameters affecting the flow injection system were evaluated with a full central composite face centered design with three center points. Under optimum conditions, a preconcentration factor of 200 was obtained with 10 ml of sample. The detection limit was 4 ng L- 1 and the relative standard deviation (RSD) for six replicate measurements at 0.2 μg L- 1 of As were 4.3% and 4.7% for As(III) and As(V), respectively. The developed methodology was highly selective towards As(III), while As(V), monomethylarsonic acid [MMA(V)] and dimethylarsinic [DMA(V)] were not retained in the AC-modified KR. The proposed method was successfully applied for As speciation analysis in infusions originated from medicinal herbs and tea.

  9. Method development for the control determination of mercury in seafood by solid-sampling thermal decomposition amalgamation atomic absorption spectrometry (TDA AAS).

    Science.gov (United States)

    Torres, D P; Martins-Teixeira, M B; Silva, E F; Queiroz, H M

    2012-01-01

    A very simple and rapid method for the determination of total mercury in fish samples using the Direct Mercury Analyser DMA-80 was developed. In this system, a previously weighted portion of fresh fish is combusted and the released mercury is selectively trapped in a gold amalgamator. Upon heating, mercury is desorbed from the amalgamator, an atomic absorption measurement is performed and the mercury concentration is calculated. Some experimental parameters have been studied and optimised. In this study the sample mass was about 100.0 mg. The relative standard deviation was lower than 8.0% for all measurements of solid samples. Two calibration curves against aqueous standard solutions were prepared through the low linear range from 2.5 to 20.0 ng of Hg, and the high linear range from 25.0 to 200.0 ng of Hg, for which a correlation coefficient better than 0.997 was achieved, as well as a normal distribution of the residuals. Mercury reference solutions were prepared in 5.0% v/v nitric acid medium. Lyophilised fish tissues were also analysed; however, the additional procedure had no advantage over the direct analysis of the fresh fish, and additionally increased the total analytical process time. A fish tissue reference material, IAEA-407, was analysed and the mercury concentration was in agreement with the certified value, according to the t-test at a 95% confidence level. The limit of quantification (LOQ), based on a mercury-free sample, was 3.0 µg kg(-1). This LOQ is in accordance with performance criteria required by the Commission Regulation No. 333/2007. Simplicity and high efficiency, without the need for any sample preparation procedure, are some of the qualities of the proposed method.

  10. Fast determination of trace elements in organic fertilizers using a cup-horn reactor for ultrasound-assisted extraction and fast sequential flame atomic absorption spectrometry.

    Science.gov (United States)

    Teixeira, Leonel Silva; Vieira, Heulla Pereira; Windmöller, Cláudia Carvalhinho; Nascentes, Clésia Cristina

    2014-02-01

    A fast and accurate method based on ultrasound-assisted extraction in a cup-horn sonoreactor was developed to determine the total content of Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn in organic fertilizers by fast sequential flame atomic absorption spectrometry (FS FAAS). Multivariate optimization was used to establish the optimal conditions for the extraction procedure. An aliquot containing approximately 120 mg of the sample was added to a 500 µL volume of an acid mixture (HNO3/HCl/HF, 5:3:3, v/v/v). After a few minutes, 500 µL of deionized water was added and eight samples were simultaneously sonicated for 10 min at 50% amplitude, allowing a sample throughput of 32 extractions per hour. The performance of the method was evaluated with a certified reference material of sewage sludge (CRM 029). The precision, expressed as the relative standard deviation, ranged from 0.58% to 5.6%. The recoveries of analytes were found to 100%, 109%, 96%, 92%, 101%, 104% and 102% for Cd, Cr, Cu, Mn, Ni, Pb and Zn, respectively. The linearity, limit of detection and limit of quantification were calculated and the values obtained were adequate for the quality control of organic fertilizers. The method was applied to the analysis of several commercial organic fertilizers and organic wastes used as fertilizers, and the results were compared with those obtained using the microwave digestion procedure. A good agreement was found between the results obtained by microwave and ultrasound procedures with recoveries ranging from 80.4% to 117%. Two organic waste samples were not in accordance with the Brazilian legislation regarding the acceptable levels of contaminants.

  11. Studies of ion-imprinted polymers for solid-phase extraction of ruthenium from environmental samples before its determination by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zambrzycka, Elzbieta; Roszko, Dorota; Lesniewska, Barbara; Wilczewska, Agnieszka Z.; Godlewska-Zylkiewicz, Beata, E-mail: bgodlew@uwb.edu.pl

    2011-07-15

    The examination of the effect of interfering ions on the analytical signal of ruthenium measured by electrothermal atomic absorption spectrometry was initially performed in this work. The complexes of ruthenium(III) with thiosemicarbazide (TSd) and acetaldehyde thiosemicarbazone (AcTSn) were prepared and imprinted in polymeric network. The ion-imprinted polymers were synthesized by copolymerization of methacrylic acid, as functional monomer and ethylene glycol dimethacrylate, as crosslinking agent in the presence of 2,2-azobisisobutyronitrile as initiator. The effects of sample volume, pH, and flow rate on the extraction of analyte were studied in dynamic mode. The optimum pH for quantitative retention of ruthenium on each of the studied sorbents was 7.5 {+-} 0.5. The elution of analyte was completed with 0.2 mol L{sup -1} thiourea in 0.2 mol L{sup -1} HCl. The effect of matrix ions on ruthenium(III) separation process was studied. The analytical performance of the Ru-TSd polymer in the presence of competing ions was better than Ru-AcTSn polymer, considering recovery of analyte, reproducibility of results, selectivity coefficients, and sorbent capacity. The detection limit of the proposed method (0.16 ng mL{sup -1} on Ru-TSd and 0.25 ng mL{sup -1} on Ru-AcTSn) is lower in comparison with the previously published methods. The developed separation method was successfully applied to the determination of trace amounts of ruthenium in spiked water samples, sludge, grass, and human hair.

  12. On-line sequential injection dispersive liquid-liquid microextraction system for flame atomic absorption spectrometric determination of copper and lead in water samples.

    Science.gov (United States)

    Anthemidis, Aristidis N; Ioannou, Kallirroy-Ioanna G

    2009-06-30

    A simple, sensitive and powerful on-line sequential injection (SI) dispersive liquid-liquid microextraction (DLLME) system was developed as an alternative approach for on-line metal preconcentration and separation, using extraction solvent at microlitre volume. The potentials of this novel schema, coupled to flame atomic absorption spectrometry (FAAS), were demonstrated for trace copper and lead determination in water samples. The stream of methanol (disperser solvent) containing 2.0% (v/v) xylene (extraction solvent) and 0.3% (m/v) ammonium diethyldithiophosphate (chelating agent) was merged on-line with the stream of sample (aqueous phase), resulting a cloudy mixture, which was consisted of fine droplets of the extraction solvent dispersed entirely into the aqueous phase. By this continuous process, metal chelating complexes were formed and extracted into the fine droplets of the extraction solvent. The hydrophobic droplets of organic phase were retained into a microcolumn packed with PTFE-turnings. A portion of 300 microL isobutylmethylketone was used for quantitative elution of the analytes, which transported directly to the nebulizer of FAAS. All the critical parameters of the system such as type of extraction solvent, flow-rate of disperser and sample, extraction time as well as the chemical parameters were studied. Under the optimum conditions the enhancement factor for copper and lead was 560 and 265, respectively. For copper, the detection limit and the precision (R.S.D.) were 0.04 microg L(-1) and 2.1% at 2.0 microg L(-1) Cu(II), respectively, while for lead were 0.54 microg L(-1) and 1.9% at 30.0 microg L(-1) Pb(II), respectively. The developed method was evaluated by analyzing certified reference material and applied successfully to the analysis of environmental water samples.

  13. Development of a method for total Hg determination in oil samples by cold vapor atomic absorption spectrometry after its extraction induced by emulsion breaking.

    Science.gov (United States)

    Vicentino, Priscila de O; Brum, Daniel M; Cassella, Ricardo J

    2015-01-01

    This work reports the development of a novel extraction method for total Hg determination in oil samples. After extracting Hg from samples it was quantified in the extracts by cold vapor atomic absorption spectrometry (CV-AAS), employing a laboratory-made gas-liquid separator (GLS) and NaBH4 as reducing agent. The extraction of Hg from samples was carried out by extraction induced by emulsion breaking (EIEB), which is based on the formation and breaking of water-in-oil emulsion between the oil samples and an extractant solution containing an emulsifying agent (surfactant) and nitric acid. Operational parameters of the GLS were evaluated in order to set the best performance of the measurement system. In these studies it was proven that the volume of sample and the concentration of HCl added to the sample extracts had significant influence on Hg response. The best conditions were achieved by adding 0.5 mL of a 0.3 mol L(-1) HCl solution on 1 mL of sample extract. The extraction conditions were also optimized. The highest efficiency was observed when 4 mL of a solution containing 2.5% triton X-100 and 15% v/v HNO3 were employed for the extraction of Hg contained in 20 mL of sample. Emulsion breaking was performed by heating at 80 °C and took approximately 20 min. The limit of quantification of the method was 1.9 µg L(-1) and recovery percentages between 80% and 103% were observed when spiked samples (2 and 10 µg L(-1)) of diesel oil, biodiesel and mineral oil were analyzed.

  14. Determination of Pb (Lead, Cd (Cadmium, Cr (Chromium, Cu (Copper, and Ni (Nickel in Chinese tea with high-resolution continuum source graphite furnace atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Wen-Si Zhong

    2016-01-01

    Full Text Available The contents of lead, cadmium, chromium, copper, and nickel were determined in 25 tea samples from China, including green, yellow, white, oolong, black, Pu'er, and jasmine tea products, using high-resolution continuum source graphite furnace atomic absorption spectrometry. The methods used for sample preparation, digestion, and quantificational analysis were established, generating satisfactory analytical precisions (represented by relative standard deviations ranging from 0.6% to 2.5% and recoveries (98.91–101.32%. The lead contents in tea leaves were 0.48–10.57 mg/kg, and 80% of these values were below the maximum values stated by the guidelines in China. The contents of cadmium and chromium ranged from 0.01 mg/kg to 0.39 mg/kg and from 0.27 mg/kg to 2.45 mg/kg, respectively, remaining in compliance with the limits stipulated by China's Ministry of Agriculture. The copper contents were 7.73–63.71 mg/kg; only 64% of these values complied with the standards stipulated by the Ministry of Agriculture. The nickel contents ranged from 2.70 mg/kg to 13.41 mg/kg. Consequently, more attention must be paid to the risks of heavy metal contamination in tea. The quantitative method established in this work lays a foundation for preventing heavy metal toxicity in human from drinking tea and will help establish regulations to control the contents of heavy metals in tea.

  15. Method validation for control determination of mercury in fresh fish and shrimp samples by solid sampling thermal decomposition/amalgamation atomic absorption spectrometry.

    Science.gov (United States)

    Torres, Daiane Placido; Martins-Teixeira, Maristela Braga; Cadore, Solange; Queiroz, Helena Müller

    2015-01-01

    A method for the determination of total mercury in fresh fish and shrimp samples by solid sampling thermal decomposition/amalgamation atomic absorption spectrometry (TDA AAS) has been validated following international foodstuff protocols in order to fulfill the Brazilian National Residue Control Plan. The experimental parameters have been previously studied and optimized according to specific legislation on validation and inorganic contaminants in foodstuff. Linearity, sensitivity, specificity, detection and quantification limits, precision (repeatability and within-laboratory reproducibility), robustness as well as accuracy of the method have been evaluated. Linearity of response was satisfactory for the two range concentrations available on the TDA AAS equipment, between approximately 25.0 and 200.0 μg kg(-1) (square regression) and 250.0 and 2000.0 μg kg(-1) (linear regression) of mercury. The residues for both ranges were homoscedastic and independent, with normal distribution. Correlation coefficients obtained for these ranges were higher than 0.995. Limits of quantification (LOQ) and of detection of the method (LDM), based on signal standard deviation (SD) for a low-in-mercury sample, were 3.0 and 1.0 μg kg(-1), respectively. Repeatability of the method was better than 4%. Within-laboratory reproducibility achieved a relative SD better than 6%. Robustness of the current method was evaluated and pointed sample mass as a significant factor. Accuracy (assessed as the analyte recovery) was calculated on basis of the repeatability, and ranged from 89% to 99%. The obtained results showed the suitability of the present method for direct mercury measurement in fresh fish and shrimp samples and the importance of monitoring the analysis conditions for food control purposes. Additionally, the competence of this method was recognized by accreditation under the standard ISO/IEC 17025.

  16. Development and validation of a general non-digestive method for the determination of palladium in bulk pharmaceutical chemicals and their synthetic intermediates by graphite furnace atomic absorption spectroscopy.

    Science.gov (United States)

    Wang, T; Walden, S; Egan, R

    1997-02-01

    A simple, selective, sensitive, accurate and relatively inexpensive method for the determination of palladium in bulk pharmaceutical chemicals (BPC) and their synthetic intermediates by graphite furnace atomic absorption spectroscopy has been developed and validated. Sample preparation by direct dissolution of sample in 70% nitric acid is simple and effective without adverse effects. The limit of detection and the limit of quantitation of the method were determined to be 0.7 ppm and 2 ppm respectively in BPC.

  17. 血中铊测定的石墨炉原子吸收光谱法%Graphite furnace atomic absorption spectrometry for determination of thallium in blood

    Institute of Scientific and Technical Information of China (English)

    张钦龙; 高舸

    2016-01-01

    目的 建立使用胶体钯化学改进剂测定血中铊含量的石墨炉原子吸收光谱法.方法 吸取1.0 ml全血,加入5%硝酸溶液1.0 ml沉淀蛋白质后,以5μl胶体钯作为化学改进剂,使用石墨炉原子吸收光谱法直接测定.在标准系列中加入0.2%氯化钠,以改善标准溶液与样品之间的基体匹配.结果 该方法的线性范围为0.2~50.0 μg/L,回归方程式为y=0.001 98x,相关系数为0.999 1,检出限为0.2 μg/L,样品加标回收率为98.0%~101.3%,相对标准偏差为1.8%~2.7%.对全血标准物质进行分析,测定结果在证书值范围内.结论 该方法操作简便,结果准确,灵敏,可以满足血中铊的测定要求.%Objective Colloidal palladium was used as chemical modifier in the determination of blood thallium by graphite furnace atomic absorption spectrometry.Methods Blood samples were precipitated with 5% (V/V) nitric acid,and then determined by GFAAS with colloidal palladium used as a chemical modifier.0.2% (W/V) sodium chloride was added in the standard series to improve the matrix matching between standard solution and sample.Results The detection limit was 0.2 μg/L.The correlation coefficient was 0.9991.The recoveries were between 93.9% to 101.5%.The relative standard deviations were between 1.8% to 2.7%.The certified reference material of whole blood thallium was determined and the result was within the reference range Conclusion The method is accurate,simple and sensitive,and it can meet the needs of detection thallium in blood entirely.

  18. Determination of Chromium(III), Chromium(VI), and Chromium(III) acetylacetonate in water by ion-exchange disk extraction/metal furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Kamakura, Nao, E-mail: minnie04_tb@yahoo.co.jp; Inui, Tetsuo; Kitano, Masaru; Nakamura, Toshihiro

    2014-03-01

    A new method for the separate determination of Chromium(III) (Cr(III)), Chromium(VI) (Cr(VI)), and Cr(III) acetylacetonate (Cr(acac){sub 3}) in water was developed using a cation-exchange extraction disk (CED) and an anion-exchange extraction disk (AED) combined with metal furnace atomic absorption spectrometry (MFAAS). A 100-mL water sample was adjusted to pH 5.6 and passed through the CED placed on the AED. Cr(acac){sub 3} and Cr(III) were adsorbed on the CED, and Cr(VI) was adsorbed on the AED. The adsorbed Cr(acac){sub 3} was eluted with 50 mL of carbon tetrachloride, followed by the elution of Cr(III) with 50 mL of 3 mol L{sup −1} nitric acid. Cr(VI) was eluted with 50 mL of 3 mol L{sup −1} nitric acid. The chemical species of Cr eluted from the CED with carbon tetrachloride was identified as Cr(acac){sub 3} using infrared spectroscopy. The eluate of Cr(acac){sub 3} was diluted to 100 mL with carbon tetrachloride, and those of Cr(III) and Cr(VI) were diluted to 100 mL with deionized water. All of the solutions were subsequently analyzed by MFAAS. The calibration curve for the Cr(acac){sub 3} aqueous solutions exhibited good linearity in the range of 0.1 to 1 ng. The detection limit of Cr, which corresponded to three times the standard deviation (n = 10) of the blank values, was 20 pg. The recovery test for Cr(III), Cr(VI), and Cr(acac){sub 3} exhibited desirable results (96.0%–107%) when 5 μg of each species (50 μg L{sup −1}) was added to 100 mL water samples (i.e., tap water, rainwater, and bottled drinking water). In a humic acid solution, Cr(acac){sub 3} was quantitatively recovered (103%), but Cr(III) and Cr(VI) exhibited poor recoveries (i.e., 84.8% and 78.4%, respectively). - Highlights: • A determination method of Cr(III), Cr(VI), and Cr(III) acetylacetonate in water was developed. • The combination of ion-exchange resin disks with metal furnace AAS was used. • No effect of humic acid on the recovery of Cr(III) acetylacetonate was

  19. Metal interferences and their removal prior to the determination of As(T) and As(III) in acid mine waters by hydride generation atomic absorption spectrometry

    Science.gov (United States)

    McCleskey, R. Blaine; Nordstrom, D. Kirk; Ball, James W.

    2003-01-01

    Hydride generation atomic absorption spectrometry (HGAAS) is a sensitive and selective method for the determination of total arsenic (arsenic(III) plus arsenic(V)) and arsenic(III); however, it is subject to metal interferences for acid mine waters. Sodium borohydride is used to produce arsine gas, but high metal concentrations can suppress arsine production. This report investigates interferences of sixteen metal species including aluminum, antimony(III), antimony(V), cadmium, chromium(III), chromium(IV), cobalt, copper(II), iron(III), iron(II), lead, manganese, nickel, selenium(IV), selenium(VI), and zinc ranging in concentration from 0 to 1,000 milligrams per liter and offers a method for removing interfering metal cations with cation exchange resin. The degree of interference for each metal without cation-exchange on the determination of total arsenic and arsenic(III) was evaluated by spiking synthetic samples containing arsenic(III) and arsenic(V) with the potential interfering metal. Total arsenic recoveries ranged from 92 to 102 percent for all metals tested except antimony(III) and antimony(V) which suppressed arsine formation when the antimony(III)/total arsenic molar ratio exceeded 4 or the antimony(V)/total arsenic molar ratio exceeded 2. Arsenic(III) recoveries for samples spiked with aluminum, chromium(III), cobalt, iron(II), lead, manganese, nickel, selenium(VI), and zinc ranged from 84 to 107 percent over the entire concentration range tested. Low arsenic(III) recoveries occurred when the molar ratios of metals to arsenic(III) were copper greater than 120, iron(III) greater than 70, chromium(VI) greater than 2, cadmium greater than 800, antimony(III) greater than 3, antimony(V) greater than 12, or selenium(IV) greater than 1. Low recoveries result when interfering metals compete for available sodium borohydride, causing incomplete arsine production, or when the interfering metal oxidizes arsenic(III). Separation of interfering metal cations using

  20. Determination of cations and metals in samples of beer and raw materials for beer production by ion chromatography (IC) and atomic absorption spectrophotometry (AAS) methods

    OpenAIRE

    Rajković, Miloš B.; Sredović-Ignjatović, Ivana; Ignjatović, Ljubiša; Nedović, Viktor; Prijić, Slobodan

    2015-01-01

    In order to control the quality of beer and raw materials for beer production, methods as ion chromatography (IC) and atomic absorption spectrophotometry (AAS) were applied. Water was analyzed as a raw material for beer production (urban, technological and demineralized water). Measurements of pH values indicated the increased pH values in the sample of tehnological water, but it had no impact on wort hopping, since the tested samples of wort, young beer and final product had a pH value in th...

  1. Quantitative analysis of immobilized metalloenzymes by atomic absorption spectroscopy.

    Science.gov (United States)

    Opwis, Klaus; Knittel, Dierk; Schollmeyer, Eckhard

    2004-12-01

    A new, sensitive assay for the quantitative determination of immobilized metal containing enzymes has been developed using atomic absorption spectroscopy (AAS). In contrast with conventionally used indirect methods the described quantitative AAS assay for metalloenzymes allows more exact analyses, because the carrier material with the enzyme is investigated directly. As an example, the validity and reliability of the method was examined by fixing the iron-containing enzyme catalase on cotton fabrics using different immobilization techniques. Sample preparation was carried out by dissolving the loaded fabrics in sulfuric acid before oxidising the residues with hydrogen peroxide. The iron concentrations were determined by flame atomic absorption spectrometry after calibration of the spectrometer with solutions of the free enzyme at different concentrations.

  2. Improved microwave-assisted wet digestion procedures for accurate Se determination in fish and shellfish by flow injection-hydride generation-atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lavilla, I. [Departamento de Quimica Analitica y Alimentaria, Area de Quimica Analitica, Universidad de Vigo, Facultad de Ciencias (Quimica), As Lagoas - Marcosende s/n, 36310 Vigo (Spain); Gonzalez-Costas, J.M. [Departamento de Quimica Analitica y Alimentaria, Area de Quimica Analitica, Universidad de Vigo, Facultad de Ciencias (Quimica), As Lagoas - Marcosende s/n, 36310 Vigo (Spain); Bendicho, C. [Departamento de Quimica Analitica y Alimentaria, Area de Quimica Analitica, Universidad de Vigo, Facultad de Ciencias (Quimica), As Lagoas - Marcosende s/n, 36310 Vigo (Spain)]. E-mail: bendicho@uvigo.es

    2007-05-22

    Accurate determination of Se in biological samples, especially fish and shellfish, by hydride generation techniques has generally proven troublesome owing to the presence of organoselenium that cannot readily converted into inorganic selenium under usual oxidising conditions. Further improvements in the oxidation procedures are needed so as to obtain accurate concentration values when this type of samples is analyzed. Microwave-assisted wet digestion (MAWD) procedures of seafood based on HNO{sub 3} or the mixture HNO{sub 3}/H{sub 2}O{sub 2} and further thermal reduction of the Se(VI) formed to Se(IV) were evaluated. These procedures were as follows: (I) without H{sub 2}O{sub 2} and without heating to dryness; (II) without H{sub 2}O{sub 2} and with heating to dryness; (III) with H{sub 2}O{sub 2} and without heating to dryness; (IV) with H{sub 2}O{sub 2} and with heating to dryness. In general, low recoveries of selenium are obtained for several marine species (e.g., crustaceans and cephalopods), which may be ascribed to the presence of Se forms mainly associated with nonpolar proteins and lipids. Post-digestion UV irradiation proved very efficient since not only complete organoselenium decomposition was achieved but also the final step required for prereduction of Se(VI) into Se(IV) (i.e. heating at 90 deg. C for 30 min in 6 M HCl) could be avoided. With the MAWD/UV procedure, the use of strong oxidising agents (persuphate, etc.) or acids (e.g. perchloric acid) which are typically applied prior to Se determination by hydride generation techniques is overcome, and as a result, sample pre-treatment is significantly simplified. The method was successfully validated against CRM DOLT-2 (dogfish liver), CRM DORM-2 (dogfish muscle) and CRM TORT-2 (lobster hepatopancreas). Automated ultrasonic slurry sampling with electrothermal atomic absorption spectrometry was also applied for comparison. Total Se contents in ten seafood samples were established. Se levels ranged from 0

  3. Determination of Fe(II) and Fe(III) in small samples by microbore ion chromatography and photometric, atomic absorption spectrometry and total-reflection X-ray fluorescence detection

    Science.gov (United States)

    Sinner, T.; Hoffmann, P.; Ortner, H. M.

    1993-02-01

    Iron(II) and iron(III) are determined after separation on an ion Chromatographie column by various detection systems. "On-line" detection was achieved by the use of a photometer with a flow cell of 0.8 μl; for "off-line" detection, graphite furnace atomic absorption spectrometry or total-reflection X-ray fluorescence were used. The applicability of the methods is shown for standard solutions and atmospheric samples. As a typical result, 50 μg/l of iron can be determined in a 10 μl sample with a nucrobore ion chromatograph-photometer and atomic absorption system and 40 μg/l of iron in a microbore ion chromatograph-total-reflection X-ray fluorescence combination.

  4. Determination of Ultra-trace Amounts of Arsenic(III) by Flow Injection Hydride Generation Atomic Absorption Spectrometry with On-line Preconcentration by Coprecipitation with Lanthanum Hydroxide or Hafnium Hydroxide

    DEFF Research Database (Denmark)

    Nielsen, Steffen; Sloth, Jens Jørgen; Hansen, Elo Harald

    1996-01-01

    A time-based flow-injection (FI) procedure for the determination of ultra-trace amounts of inorganic arsenic(III) is described, which combines hydride generation atomic absorption spectrometry (HG-AAS) with on-line preconcentration of the analyte by inorganic coprecipitation-dissolution in a filt......A time-based flow-injection (FI) procedure for the determination of ultra-trace amounts of inorganic arsenic(III) is described, which combines hydride generation atomic absorption spectrometry (HG-AAS) with on-line preconcentration of the analyte by inorganic coprecipitation....../h. The limit of detection (3s) was 0.003 µg/l and the precision (relative standard deviation) was 1.0% (n = 11)at the 0.1 µg/l level....

  5. The absorptive line shape of hadronic atoms

    CERN Document Server

    Ericson, Torleif Eric Oskar

    1977-01-01

    The exact line shape for all energies is derived analytically in the limit of negligible nuclear dimensions. The shape deviates from the Breit-Wigner form. The high-energy tail of the line has a universal shape, independent of the absorptive strength. The tails are different for different initial states, however. The integrated line strength diverges logarithmically. Renormalization of the hadron wavefunction by strong interactions leads to the usual shape near resonance and restores convergence for very large energies. The results resolve a logical inconsistency in the normal analysis of hadronic atoms and are of practical importance. It is shown that bound hadronic states (e.g. Y/sub 0/*) give natural contributions in the high energy region. Numerical illustrations are given. (6 refs).

  6. [The content of mineral elements in Camellia olei fera ovary at pollination and fertilization stages determined by auto discrete analyzers and atomic absorption spectrophotometer].

    Science.gov (United States)

    Zou, Feng; Yuan, De-Yi; Gao, Chao; Liao, Ting; Chen, Wen-Tao; Han, Zhi-Qiang; Zhang, Lin

    2014-04-01

    In order to elucidate the nutrition of Camellia olei fera at pollination and fertilization stages, the contents of mineral elements were determined by auto discrete analyzers and atomic absorption spectrophotometer, and the change in the contents of mineral elements was studied and analysed under the condition of self- and cross-pollination. The results are showed that nine kinds of mineral elements contents were of "S" or "W" type curve changes at the pollination and fertilization stages of Camellia olei fera. N, K, Zn, Cu, Ca, Mn element content changes showed "S" curve under the self- and out-crossing, the content of N reaching the highest was 3.445 8 mg x g(-1) in self-pollination of 20 d; K content reaching the highest at the cross-pollination 20 d was 6.275 5 mg x g(-1); Zn content in self-pollination of 10 d reaching the highest was 0.070 5 mg x g(-1); Cu content in the cross-pollination of 5 d up to the highest was 0.061 0 mg x g(-1); Ca content in the cross-pollination of 15 d up to the highest was 3.714 5 mg x g(-1); the content of Mn reaching the highest in self-pollination 30 d was 2. 161 5 mg x g(-1). Fe, P, Mg element content changes was of "S" type curve in selfing and was of "W" type curve in outcrossing, Fe content in the self-pollination 10 d up to the highest was 0.453 0 mg x g(-1); P content in self-pollination of 20 d reaching the highest was 6.731 8 mg x g(-1); the content of Mg up to the highest in self-pollination 25 d was 2.724 0 mg x g(-1). The results can be used as a reference for spraying foliar fertilizer, and improving seed setting rate and yield in Camellia olei fera.

  7. Combination of dispersive liquid-liquid microextraction with flame atomic absorption spectrometry using microsample introduction for determination of lead in water samples

    Energy Technology Data Exchange (ETDEWEB)

    Naseri, Mohammad Taghi; Hemmatkhah, Payam; Hosseini, Mohammad Reza Milani [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Assadi, Yaghoub [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)], E-mail: y_assadi@iust.ac.ir

    2008-03-03

    The dispersive liquid-liquid microextraction (DLLME) was combined with the flame atomic absorption spectrometry (FAAS) for determination of lead in the water samples. Diethyldithiophosphoric acid (DDTP), carbon tetrachloride and methanol were used as chelating agent, extraction solvent and disperser solvent, respectively. A new FAAS sample introduction system was employed for the microvolume nebulization of the non-flammable chlorinated organic extracts. Injection of 20 {mu}L volumes of the organic extract into an air-acetylene flame provided very sensitive spike-like and reproducible signals. Some effective parameters on the microextraction and the complex formation were selected and optimized. These parameters include extraction and disperser solvent type as well as their volume, extraction time, salt effect, pH and amount of the chelating agent. Under the optimized conditions, the enrichment factor of 450 was obtained from a sample volume of 25.0 mL. The enhancement factor, calculated as the ratio of the slopes of the calibration graphs with and without preconcentration, which was about 1000. The calibration graph was linear in the range of 1-70 {mu}g L{sup -1} with a detection limit of 0.5 {mu}g L{sup -1}. The relative standard deviation (R.S.D.) for seven replicate measurements of 5.0 and 50 {mu}g L{sup -1} of lead were 3.8 and 2.0%, respectively. The relative recoveries of lead in tap, well, river and seawater samples at the spiking level of 20 {mu}g L{sup -1} ranged from 93.8 to 106.2%. The characteristics of the proposed method were compared with those of the liquid-liquid extraction (LLE), cloud point extraction (CPE), on-line and off-line solid-phase extraction (SPE) as well as co-precipitation, based on bibliographic data. Operation simplicity, rapidity, low cost, high enrichment factor, good repeatability, and low consumption of the extraction solvent at a microliter level are the main advantages of the proposed method.

  8. Determination of trace amounts of selenium in minerals and rocks by flame less atomic-absorption spectrometry; Determinacion de selinio en minerales y rocas por espectrometria de absorcion atomica

    Energy Technology Data Exchange (ETDEWEB)

    Alduan, F. A.; Capdevilla, C.

    1980-07-01

    The determination of trace amounts of selenium In silicate rocks and feldspar by solvent extraction and graphite furnace atomic-absorption spectrometry has been stu- died. Sodium diethyl-ditio carbamate and ammonium pyrrolidine dithiocarbamate have been tried as chelating agents. The best results are achieved when selenium is extracted Into carbon tetrachloride as the sodium diethyldithiocarbamate complex. The method allows to detect 0,75 ppm of selenium in the sample. Recoveries are about 100%. (Author) 7 refs.

  9. A novel analytical system involving hydride generation and gold-coated W-coil trapping atomic absorption spectrometry for selenium determination at ng l{sup -1} level

    Energy Technology Data Exchange (ETDEWEB)

    Kula, I. [Department of Chemistry, Mugla University, 48000 Mugla (Turkey); Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Arslan, Y. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Chemistry, Atatuerk University, 25240 Erzurum (Turkey); Bakirdere, S. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Chemistry, Zonguldak Karaelmas University, 67100 Zonguldak (Turkey); Ataman, O.Y. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey)], E-mail: ataman@metu.edu.tr

    2008-08-15

    A novel analytical technique was developed where gaseous hydrogen selenide formed by sodium tetrahydroborate reduction is transported to and trapped on a resistively heated gold-coated W-coil atom trap for in situ preconcentration. Gold coating on W-coil was prepared by using an organic solution of Au. The atom trap is held at 165 {sup o}C during the collection stage and is heated up to 675 deg. C for revolatilization; analyte species formed are transported to an externally heated quartz T-tube where the atomization takes place and the transient signal is obtained. The carrier gas consisted of 112.5 ml min{sup -1} Ar with 75 ml min{sup -1} H{sub 2} during the collection step and 112.5 ml min{sup -1} Ar with 450 ml min{sup -1} H{sub 2} in the revolatilization step. The half width of the transient signal obtained is less than 0.5 s. The RSD for the measurements was found to be 3.9% (n = 11) for 0.10 {mu}g l{sup -1} Se using peak height measurements. The calibration plot for 27.0 ml of sample collected in 4.0 min using a flow rate of 6.75 ml min{sup -1} was linear between 0.13 and 2.0 {mu}g l{sup -1} of Se. The limit of detection (3 s) is 39 ng l{sup -1}. The enhancement factor for the characteristic concentration (C{sub o}) was found to be 20.1 when compared to conventional hydride generation atomic absorption spectrometry system without trap. In order to check the accuracy of the method, standard reference material, natural water NIST 1640 was employed; the result was found to be in good agreement with the certified value at the 95% confidence level.

  10. A novel analytical system involving hydride generation and gold-coated W-coil trapping atomic absorption spectrometry for selenium determination at ng l - 1 level

    Science.gov (United States)

    Kula, İ.; Arslan, Y.; Bakırdere, S.; Ataman, O. Y.

    2008-08-01

    A novel analytical technique was developed where gaseous hydrogen selenide formed by sodium tetrahydroborate reduction is transported to and trapped on a resistively heated gold-coated W-coil atom trap for in situ preconcentration. Gold coating on W-coil was prepared by using an organic solution of Au. The atom trap is held at 165 °C during the collection stage and is heated up to 675 °C for revolatilization; analyte species formed are transported to an externally heated quartz T-tube where the atomization takes place and the transient signal is obtained. The carrier gas consisted of 112.5 ml min - 1 Ar with 75 ml min - 1 H 2 during the collection step and 112.5 ml min - 1 Ar with 450 ml min - 1 H 2 in the revolatilization step. The half width of the transient signal obtained is less than 0.5 s. The RSD for the measurements was found to be 3.9% ( n = 11) for 0.10 µg l - 1 Se using peak height measurements. The calibration plot for 27.0 ml of sample collected in 4.0 min using a flow rate of 6.75 ml min - 1 was linear between 0.13 and 2.0 µg l - 1 of Se. The limit of detection (3 s) is 39 ng l - 1 . The enhancement factor for the characteristic concentration ( Co) was found to be 20.1 when compared to conventional hydride generation atomic absorption spectrometry system without trap. In order to check the accuracy of the method, standard reference material, natural water NIST 1640 was employed; the result was found to be in good agreement with the certified value at the 95% confidence level.

  11. Determination of metallic impurities in raw materials for radioisotope production by atomic absorption spectroscopy; Determinacion de trazas metalicas en amterias primas para la produccion de radioisotopos por espectroscopia de absorcion atomica

    Energy Technology Data Exchange (ETDEWEB)

    Roca, M.; Alvarez, F.; Capdevila, C.

    1969-07-01

    Atomic absorption spectrometry has been used for the determination of traces of calcium in scandium oxide, copper in zinc, iron in cobalt oxide, manganese In ferric oxide, nickel in copper and zinc in gallium oxide. The influences on the sensitivities arising from the hollow cathode currents, the gas pressures and the acid concentrations have been considered. A study of the interferences from the metallic matrices has also been performed, the interference due to the absorption of the manganese radiation by the atoms of iron being the most outstanding . In order to remove the interfering elements and increase sensitivity, pre-concentration methods have been tested. The addition methods has also been used. (Author) 14 refs.

  12. Differential determination of arsenic(III) and arsenic(V), and antimony(III) and antimony-(V) by hydride generation-atomic absorption spectrophotometry, and its application to the determination of these species in sea water

    Science.gov (United States)

    Yamamoto, Manabu; Urata, Keiji; Murashige, Kiyoto; Yamamoto, Yuroku

    A method is described for the differential determination of As(III) and As(V). and Sb(III) and Sb(V) by hydride generation-atomic absorption spectrophotometry with hydrogen-nitrogen flame using sodium borohydride solution as a reductant. For the determination of As(III) and Sb(III), most of the elements, other than Ag +, Cu 2+, Sn 2+, Se 4+ and Te 4+, do not interfere in an at least 30,000 fold excess with respect to As(III) or Sb(III). This method was applied to the determination of these species in sea water and it was found that a sample size of only 100 ml is enough to determine them with a precision of 1.5-2.5%. Analytical results for surface sea water of Hiroshima Bay were 0.72 μgl -1, 0.27 μgl -1 and 0.22 μgl -1 for As(total), As(III) and Sb(total), respectively, but Sb(III) was not detected in the present sample. The effect of acidification on storage was also examined.

  13. Espectrometria de absorção atômica: o caminho para determinações multi-elementares Atomic absorption spectrometry: the way for multielement determinations

    Directory of Open Access Journals (Sweden)

    Fábio Alan Carqueija Amorim

    2008-01-01

    Full Text Available This paper present an overview of way covered for the spectrometry of atomic absorption (AAS, tracing a line of the historical events in its development and its establishment as a multielement technique. Additionally, the efforts carried by through several researchers in the search for the instrumental evolution, the advances, advantages, limitations, and trends of this approach are related. Several works focusing its analytical applications are cited employing simultaneous multielement determination by flame (FAAS and/or graphite furnace (GF AAS, and fast sequential multielement determination using FAAS are reported in the present review.

  14. Use of long-chain alkylamines for preconcentration and determination of traces of molybdenum, tungsten and rhenium by atomic-absorption spectroscopy-II: molybdenum in soils, sediments and natural waters.

    Science.gov (United States)

    Kim, C H; Alexander, P W; Smythe, L E

    1976-03-01

    Molybdenum is extracted as the thiocyanate complex with the quaternary long-chain aliphatic amine Aliquat 336 in chloroform, followed by evaporation of the solvent, dissolution in MIBK, and atomic-absorption spectroscopy. The method is simple, rapid and sensitive, with few interference problems for the determination of the Mo content of soils and sediments in the range 0.1-1.0 ppm with a relative standard deviation better than 5% when 1-g samples are used. Quantitative extraction from large volumes of aqueous solution has also been confirmed, allowing the determination of Mo in natural waters in the ppM range.

  15. Determination of essential elements in beverages, herbal infusions and dietary supplements using a new straightforward sequential approach based on flame atomic absorption spectrometry.

    Science.gov (United States)

    Gómez-Nieto, Beatriz; Gismera, Mª Jesús; Sevilla, Mª Teresa; Procopio, Jesús R

    2017-03-15

    A simple method based on FAAS was developed for the sequential multi-element determination of Cu, Zn, Mn, Mg and Si in beverages and food supplements with successful results. The main absorption lines for Cu, Zn and Si and secondary lines for Mn and Mg were selected to carry out the measurements. The sample introduction was performed using a flow injection system. Using the choice of the absorption line wings, the upper limit of the linear range increased up to 110mgL(-1) for Mg, 200mgL(-1) for Si and 13mgL(-1) for Zn. The determination of the five elements was carried out, in triplicate, without the need of additional sample dilutions and/or re-measurements, using less than 3.5mL of sample to perform the complete analysis. The LODs were 0.008mgL(-1) for Cu, 0.017mgL(-1) for Zn, 0.011mgL(-1) for Mn, 0.16mgL(-1) for Si and 0.11mgL(-1) for Mg.

  16. Determination of metals in lubricating oils by flame atomic absorption spectrometry using a single-bore high-pressure pneumatic nebulizer.

    Science.gov (United States)

    Mora, J; Todolí, J L; Sempere, F J; Canals, A; Hernandis, V

    2000-12-01

    The behaviour of a single-bore high-pressure pneumatic nebulizer (SBHPPN) as a tool for the analysis of lubricating oils by flame atomic absorption spectrometry (FAAS) was investigated. The effects of the sample oil content [from 10% to 100% (w/w) oil in 4-methylpentan-2-one, IBMK] and the carrier nature (IBMK and methanol) on the characteristics of the aerosols generated, on the analyte transport efficiency and on the analytical figures of merit in FAAS were studied. A pneumatic concentric nebulizer (PCN) was used for comparison. Increasing the oil content increases the viscosity of the sample. With the PCN this gives rise to coarser aerosols, making it impossible to nebulize samples with an oil content higher than 70% (w/w). Using the SBHPPN, the viscosity of the sample scarcely affects the characteristics of the primary aerosols. Hence, the SBHPPN is able, by using the appropriate carrier, to nebulize pure lubricating oils. Among the carriers tested, IBMK is the most advisable because it is fully miscible with all the oil samples. The SBHPPN provides higher sensitivities and lower limits of detection than the PCN. Compared with a method based on organic dilution, the use of the SBHPPN for the direct analysis of lubricating oils by FAAS makes it possible, in addition to increasing the analysis throughput, to detect elements at lower concentrations. Moreover, the SBHPPN provides similar results to those obtained using a previous acid digestion step.

  17. Preconcentration of trace amounts of lead in water samples with cetyltrimethylammonium bromide coated magnetite nanoparticles and its determination by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Mohammad Faraji

    2016-11-01

    Full Text Available A sensitive and simple magnetic solid phase extraction procedure was presented for the preconcentration of lead ions in environmental water samples. In the present study, lead ions form complexes with 1-(2-pyridilazo-2-naphthol reagent (PAN in basic medium, and then are quantitatively extracted to the surface of cetyltrimethylammonium bromide (CTAB-coated magnetite nanoparticles (Fe3O4 NPs. After magnetic separation of adsorbent, the adsorbent was eluted with 0.5% (v/v HCl in methanol prior to its analysis by flame atomic absorption spectrometry (FAAS. The pH of sample, concentrations of PAN, amounts of CTAB and Fe3O4 NPs, sample volume and desorption conditions were optimized. Under optimum conditions, the calibration curve was linear in the range of 0.05–100 ng mL−1 with R2 = 0.9996. Detection and quantification limits of the proposed method were 0.005 and 0.05 ng mL−1, respectively. Enhancement factor of 1050 was achieved using this method to extract 1000 mL of different environmental water samples. Compared with conventional solid phase extraction methods, the advantages of this method still include easy preparation of sorbents, short times of sample pre-treatment, high extraction yield, and high breakthrough volume. It shows great analytical potential in preconcentration of lead from large volume water samples.

  18. Mercury(II) and methyl mercury determinations in water and fish samples by using solid phase extraction and cold vapour atomic absorption spectrometry combination.

    Science.gov (United States)

    Tuzen, Mustafa; Karaman, Isa; Citak, Demirhan; Soylak, Mustafa

    2009-07-01

    A method has been developed for mercury(II) and methyl mercury speciation on Staphylococcus aureus loaded Dowex Optipore V-493 micro-column in the presented work, by using cold vapour atomic absorption spectrometry. Selective and sequential elution with 0.1 molL(-1) HCl for methyl mercury and 2 molL(-1) HCl for mercury(II) were performed at the pH range of 2-6. Optimal analytical conditions including pH, amounts of biosorbent, sample volumes were investigated. The detection limits of the analytes were 2.5 ngL(-1) for Hg(II) and 1.7 ngL(-1) for methyl mercury. The capacity of biosorbent for mercury(II) and methyl mercury was 6.5 and 5.4 mgg(-1), respectively. The validation of the presented procedure is performed by the analysis of standard reference material. The speciation procedure established was successfully applied to the speciation of mercury(II) and methyl mercury in natural water and microwave digested fish samples.

  19. 石墨炉原子吸收法测定萝卜中的硒%Graphite Furnace Atomic Absorption Method for the Determination of Selenium in Raphanus sativus L.

    Institute of Scientific and Technical Information of China (English)

    铁梅; 张莹; 张朝红; 惠秀娟; 陈忠林; 刘阳; 李宝瑞

    2013-01-01

    [Objective] Determination of selenium in Raphanus sativus L.by Graphite Furnace Atomic Absorption Spectrometry.[Method] Compared single ion(Cu,Ni,Pd) and mixing ion (Cu-Pd,Ni-Pd) by Graphite Furnace Atomic Absorption method for determination of selenium in improving action; To determine the optimal method for the determination of selenium by graphite furnace atomic absorption spectrometry by optimizing the lamp current,ashing temperature and atomization temperature,and determination of selenium in Raphanus sativus L..[Result] The result showed that 1 mg/ml Cu(NO3)2 as matrix modifier,ashing temperature and atomization temperature in 800 ℃,2 500 ℃ for optimum conditions of selenium content in Raphanus sativus L..The recovery rate was 99.6%-106.0%,relative standard deviation is 1.19%,the detection limit is 0.79 μg/L.[Conclusion] This method is simple,sensitive,stable,accurate,applicable to selenium determination in Raphanus sativus L..%[目的]建立石墨炉原子吸收法测定萝卜中硒的方法.[方法]比较了Cu、Ni、Pd及Cu-Pd、Ni-Pd协同作用对硒的测定的影响,确定最佳基改剂;通过优化灯电流、灰化温度和原子化温度等确定石墨炉原子吸收法测定硒的最佳方法,并测定萝卜中的硒.[结果]1mg/ml Cu(NO3)2作为基体改进剂,灰化温度800℃,原子化温度2 500℃为测定不同萝卜中硒的含量的适宜条件.在该条件下测定Se的加标回收率在99.6% ~ 106.0%,方法相对标准偏差为1.19%,检出限为0.79 μg/L.[结论]该方法简便、灵敏、稳定、准确,适用于萝卜中硒的分析测定.

  20. Determination of trace elements in tomatoes by flame atomic absorption spectrometry(FAAS)%火焰原子吸收法测定番茄中的微量元素

    Institute of Scientific and Technical Information of China (English)

    张伟党; 邱舒; 唐国钢; 石秋忠

    2011-01-01

    采用火焰原子吸收法对镇江市农产品批发市场出售的番茄中Mg,Fe,Cu,Zn等4种元素含量进行测定。结果表明,番茄中含有Mg,Fe,Zn,Cu等对人体有益的微量元素。%The contents of four trace elements in tomatoes sold in Zhenjiang agricultural products wholesale market were determined by flame atomic absorption spectrometry(FAAS).The results showed that red Fuji apple contains trace elements of Mg,Fe,Cu and Zn that are beneficial to human body.

  1. Determination of nickel in blood and serum samples of oropharyngeal cancer patients consumed smokeless tobacco products by cloud point extraction coupled with flame atomic absorption spectrometry.

    Science.gov (United States)

    Arain, Sadaf Sadia; Kazi, Tasneem Gul; Arain, Jamshed Bashir; Afridi, Hassan Imran; Kazi, Atif Gul; Nasreen, Syeda; Brahman, Kapil Dev

    2014-10-01

    Oropharyngeal cancer is a significant public health issue in the world. The incidence of oropharyngeal cancer has been increased among people who have habit of chewing smokeless tobacco (SLT) in Pakistan. The aim of present study was to evaluate the concentration of nickel (Ni) in biological samples (whole blood, serum) of oral (n = 95) and pharyngeal (n = 84) male cancer patients. For comparison purposes, the biological samples of healthy age-matched referents (n = 150), who consumed and did not consumed SLT products, were also analyzed for Ni levels. As the Ni level is very low in biological samples, a preconcentration procedure has been developed, prior to analysis of analyte by flame atomic absorption spectrometry (FAAS). The Ni in acid-digested biological samples was complexed with ammonium pyrrolidinedithio carbamate (APDC), and a resulted complex was extracted in a surfactant Triton X-114. Acidic ethanol was added to the surfactant-rich phase prior to its analysis by FAAS. The chemical variables, such as pH, amounts of reagents (APDC, Triton X-114), temperature, incubation time, and sample volume were optimized. The resulted data indicated that concentration of Ni was higher in blood and serum samples of cancer patients as compared to that of referents who have or have not consumed different SLT products (p = 0.012-0.001). It was also observed that healthy referents who consumed SLT products have two to threefold higher levels of Ni in both biological samples as compared to those who were not chewing SLT products (p < 0.01).

  2. Method development and optimization for the determination of selenium in bean and soil samples using hydride generation electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Shaltout, Abdallah A; Castilho, Ivan N B; Welz, Bernhard; Carasek, Eduardo; Martens, Irland B Gonzaga; Martens, Andreas; Cozzolino, Silvia M F

    2011-09-15

    The present investigation is the first part of an initiative to prepare a regional map of the natural abundance of selenium in various areas of Brazil, based on the analysis of bean and soil samples. Continuous-flow hydride generation electrothermal atomic absorption spectrometry (HG-ET AAS) with in situ trapping on an iridium-coated graphite tube has been chosen because of the high sensitivity and relative simplicity. The microwave-assisted acid digestion for bean and soil samples was tested for complete recovery of inorganic and organic selenium compounds (selenomethionine). The reduction of Se(VI) to Se(IV) was optimized in order to guarantee that there is no back-oxidation, which is of importance when digested samples are not analyzed immediately after the reduction step. The limits of detection and quantification of the method were 30 ng L(-1) Se and 101 ng L(-1) Se, respectively, corresponding to about 3 ng g(-1) and 10 ng g(-1), respectively, in the solid samples, considering a typical dilution factor of 100 for the digestion process. The results obtained for two certified food reference materials (CRM), soybean and rice, and for a soil and sediment CRM confirmed the validity of the investigated method. The selenium content found in a number of selected bean samples varied between 5.5±0.4 ng g(-1) and 1726±55 ng g(-1), and that in soil samples varied between 113±6.5 ng g(-1) and 1692±21 ng g(-1).

  3. A study of the distribution of aluminium in human placental tissues based on alkaline solubilization with determination by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Kruger, Pamela C; Schell, Lawrence M; Stark, Alice D; Parsons, Patrick J

    2010-09-01

    Aluminium (Al) is a nonessential element known to induce neurotoxic effects, such as dialysis dementia, in patients on hemodialysis, with compromised kidney function. The role of Al in the progression of some neurodegenerative diseases, such as Alzheimer's disease (AD), is controversial, and remains unclear. The effects of Al on other vulnerable populations, such as fetuses and infants, have been infrequently studied. In the present study, Al has been measured in human placenta samples, comprising ∼160 each of placenta bodies, placenta membranes, and umbilical cords, using electrothermal atomic absorption spectrometry (ETAAS) after atmospheric pressure digestion with tetramethylammonium hydroxide (TMAH) and ethylenediaminetetraacidic acid (EDTA). The sensitivity, or characteristic mass (m(0)), for Al at the 309.3-nm line was found to be 30 ± 4 pg. The instrumental detection limit (IDL) (3s) for Al in solution was calculated as 0.72 μg L(-1) while the method detection limit (MDL) (3s) was 0.25 μg g(-1). Accuracy was assessed through analysis of quality control (QC) materials, including certified reference materials (CRMs), in-house reference materials (RMs), and spike recovery experiments, of varying matrices. Placental tissue analyses revealed geometric mean concentrations of approximately 0.5 μg g(-1) Al in placenta bodies (n = 165) and membranes (n = 155), while Al concentrations in umbilical cords (n = 154) were about 0.3 μg g(-1). Al was detected in 95% of placenta bodies, and 81% of placenta membranes, but only in 46% of umbilical cords.

  4. Determination of the Content of Zinc and Copper in Sewage Sludge by Microwave Digestion-atomic Absorption Method%微波消解-原子吸收法测定污泥中的铜、锌含量

    Institute of Scientific and Technical Information of China (English)

    任旭锋; 王长智; 李娇英

    2015-01-01

    参考环境标准》固体废物镍铜的测定》和》固体废物铅锌隔的测定》优化了原子吸收仪工作参数和微波消解条件,建立了微波消解-原子吸收法测定太阳能电池行业废水处理后污泥中的铜和锌元素的分析方法,方法的检出限范围为0.001~0.009 mg/L,方法加标回收率93.3%~109%,相对标准偏差RSD均小于5%。%An analysis method as microwave digestion-atomic absorption spectroscopy ( ADAAS) was established for the determination of copper and zinc in the sludge from the treatment of solar cell industry wastewater.With reference to the environmental standards of Determination of Nickel and Copper Solid Waste and Determination of Lead, Zinc and Cadmium Solid Waste, the microwave digestion conditions as well as the operating parameters of atomic absorption spectrometer were optimized.The detection limit of this method was in the range of 0.001 ~0.009 mg/L.The relative standard deviation ( RSD) was less than 5%and recoveries were 93.3%~109.0%.

  5. 微波消解-石墨炉原子吸收光谱法测定儿童发铅%Microwave digestion-graphite furnace atomic absorption spectrometry for the determination of lead in children's hair

    Institute of Scientific and Technical Information of China (English)

    陈宇鸿; 沈仁富

    2012-01-01

    目的:建立发中铅的微波消解-石墨炉原子吸收光谱测定法.方法:样品经微波消解后,石墨炉原子吸收光谱法测定.结果:方法标准曲线相关系数为0.9996,相对标准偏差1.15% ~2.16%,回收率为94.4% ~ 102%.结论:该法准确、灵敏,是高效、快速、实用的测定发中铅的方法.%Objective: To establish microwave digestion - graphite furnace atomic absorption spectrometry for the determination of lead in children's hair. Methods:The samples were digested with microwave oven and determined by graphite furnace atomic absorption spectrometry. Results: The correlation coefficient of the metod was 0. 9996 with RSDs of 1. 15% ~2. 16% and average recoveries of 94.4% ~ 102%. Conclusion: The method is accurate,precisive and sensitive, it is suitable for the determination of lead in hair.

  6. Atomic-absorption determination of mercury in geological materials by flame and carbon-rod atomisation after solvent extraction and using co-extracted silver as a matrix modifier

    Science.gov (United States)

    Sanzolone, R.F.; Chao, T.T.

    1983-01-01

    Based on modifications and expansion of the original Tindall's solvent extraction flame atomic-absorption procedure, an atomic-absorption spectrophotometric method has been developed for the determination of mercury in geological materials. The sample is digested with nitric and hydrochloric acids in a boiling water-bath. The solution is made ammoniacal and potassium iodide and silver nitrate are added. The mercury is extracted into isobutyl methyl ketone as the tetraiodomercurate(ll). Added silver is co-extracted with mercury and serves as a matrix modifier in the carbon-rod atomiser. The mercury in the isobutyl methyl ketone extract may be determined by either the flame- or the carbon-rod atomisation method, depending on the concentration level. The limits of determination are 0.05-10 p.p.m. of mercury for the carbon-rod atomisation and 1 -200 p.p.m. of mercury for the flame atomisation. Mercury values for reference samples obtained by replicate analyses are in good agreement with those reported by other workers, with relative standard deviations ranging from 2.3 to 0.9%. Recoveries of mercury spiked at two levels were 93-106%. Major and trace elements commonly found in geological materials do not interfere.

  7. 原子吸收分光光度法测定多烯磷脂酰胆碱中砷盐含量%Determination of Arsenic Salt Content in Polyene Phosphatidyl Choline by Atomic Absorption Spectryphotometry

    Institute of Scientific and Technical Information of China (English)

    丘文嘉; 张玉英

    2015-01-01

    Objective To innovatively establish an atomic absorption spectrophotometric method for determining the arsenic salt content in polyene phosphatidyl choline. Methods After the sample digestion by mized acid,the atomic absorption spectrophotometric method was adopted to detect arsenic at the characteristic absorption wavelength of arsenic element(193. 7 nm). Results The mass concentration of arsenic demonstrated a good linear relationship with the absorption in the range of 0-20 ng/mL,r=0. 999 4( n=5),and the adding standard recovery rate was good. Conclusion The method is simple and accurate with little interference,and can be used for the deter-mination of arsenic salt content in polyene phosphatidyl choline.%目的:创新性地建立测定多烯磷脂酰胆碱中砷盐含量的原子吸收分光光度法。方法样品经混合酸消解后,采用原子吸收分光光度法在砷元素的特征吸收波长(193.7 nm)处测定砷。结果砷的质量浓度在0~20 ng/mL范围内与吸光度线性关系良好,r=0.9994( n=5),加样回收率良好。结论该方法操作简便、准确、干扰少,可用于多烯磷脂酰胆碱中砷盐含量的测定。

  8. Determination of total and methyl mercury in human permanent healthy teeth by electrothermal atomic absorption spectrometry after extraction in organic phase.

    Science.gov (United States)

    Saber-Tehrani, M; Givianrad, M H; Hashemi-Moghaddam, H

    2007-02-28

    A simple and sensitive method has been developed for determination of inorganic and methyl mercury in biological samples by ETAAS. For determination of methyl mercury; it was transferred to toluene phase by acid leaching extraction method. For total mercury after digestion of samples; it was extracted to toluene phase by means of the chelating agent diethyldithiocarbamate. Formation of complex between MeHg and diethyldithiocarbamate enhance the MeHg signal and increases the reproducibility. Furthermore, Pd-DDC was used as modifier for both mercury and methyl mercury determinations. The optimization performance was independently carried out by modifying the parameters such as temperature of mineralization, atomization and gas flow rate for methylmercury and inorganic mercury in ETAAS. The limits of detection were 0.15 and 0.12mugg(-1) for methyl mercury and total mercury, respectively. The repeatability of the measurements of whole procedure were 15.8% for methyl mercury and 16.9% for total mercury determination. The accuracy of the method has been investigated by means of spiking different amounts of methylmercury and inorganic mercury to the samples. The recoveries were found within the range of 88-95% for methyl mercury and 85-92% for total mercury. For determination of total mercury, the method was validated by CVAAS. The obtained results by the present procedure were in good agreement with those of the CVAAS. The proposed method was applied for 30 human permanent healthy teeth (without filling) which significant positive correlations were found among number of amalgam filling and total mercury and MeHg.

  9. 原子吸收光谱法测定桃儿七中微量金属元素含量%Determination of micronutrient in sinopodophyllum emodi by atomic absorption spectrophotometry

    Institute of Scientific and Technical Information of China (English)

    温普红; 赵卫星; 王艳

    2011-01-01

    目的:应用原子吸收光谱法测定桃儿七中微量金属元素.方法:采用原子发射光谱法进行定性分析,原子吸收光谱法进行定量分析.结果:桃儿七中微量元素的含量为:钙449.1 mg/kg;镁48.5 mg/kg;锌55.3 mg/kg;铜195.1 mg/kg;锰16.8 mg/kg;铁188.6 mg/kg,RSD≤0.8%,加样回收率为97.9%~102.1%.结论:该方法准确度较高,简便易行,处理一次样品可连续测定多种元素.%Objective: To determine the micronutfient in sinopodophyllum emodi by atomic absorption sepctrophotometry.Methods: The qualitative determination was carried out by atomic emission spectrometry (AES) method.On the basis of the resuhs, atomic absorption spectrometry (AAS) method was developed to determine micronutrient in sinopodophyllum emodi.Results: The micronutrient of Ca, Mg, Zn, Ca, Mn and Fe in sinopodophyllum emodi was respectively 449.1, 48.5, 55.3,195.1, 16.8, 188.6 mg/kg in the sample with RSD ≤0.8%, and the recoveries were 97.9%-102.1%.Conclusion: This method is exact and handy, and can be used in sequential determination of multi-elements in one sample solution.

  10. 原子吸收光谱法测定活性污泥中Cu、Zn、Pb、Cd、Ni%Determination of Cu, Zn, Pb, Cd and Ni in Activated Sludge by Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    张继蓉; 印成; 李显芳

    2013-01-01

    Samples of activated sludge were digested by microwave, copper and zinc were determined by flame atomic absorption spectrometry, and lead, cadmium and nickel were determined by graphite furnace atomic absorption spectrometry. The method was validated by the recoveries of standard additions and standard material. The precision and accuracy of the method could meet the testing requirement for sludge samples. Under the experimental conditions, the recovery rates of copper, zinc, lead, cadmium and nickel in the samples were in the range of 95. 2% to 103% , and the RSDs were less than 3%.%采用微波消解技术消解城市污水处理厂污泥样品,用火焰原子吸收光谱法测定Cu、Zn,石墨炉原子吸收光谱法测定Pb、Cd、Ni.通过测定国家标准参考物质和加标回收试验,对方法进行了验证,方法的精密度和准确度均能满足污泥环境样品的测试要求.在试验条件下,测定样品中Cu、Zn、Pb、Cd、Ni的加标回收率在95.2%~103%之间,相对标准偏差<3%.

  11. Solid phase extraction of ultra traces silver(I) using octadecyl silica membrane disks modified by 1,3-bis(2-cyanobenzene) triazene (CBT) ligand prior to determination by flame atomic absorption

    Energy Technology Data Exchange (ETDEWEB)

    Rofouei, Mohammad Kazem, E-mail: rofouei@tmu.ac.ir [Faculty of Chemistry, Tarbiat Moalem University, Tehran (Iran, Islamic Republic of); Payehghadr, Mahmood [Department of Chemistry, Payame Noor University (PNU) (Iran, Islamic Republic of); Shamsipur, Mojtaba [Department of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of); Ahmadalinezhad, Asieh [Department of Chemistry, Lakehead University, Thunder Bay, Ontario P7B 5E1 (Canada)

    2009-09-15

    A simple, reliable and rapid method for preconcentration and determination of the ultra trace amount of silver using octadecyl silica membrane disk modified by a recently synthesized triazene ligand, 1,3-bis(2-cyanobenzene)triazene (CBT), and flame atomic absorption spectrometry is presented. Various parameters including pH of aqueous solution, flow rates, the amount of ligand and the type of stripping solvents were optimized. The breakthrough volume was greater than 1800 ml with an enrichment factor of more than 360 and 6.0 ng l{sup -1} detection limit. The capacity of the membrane disks modified by 5 mg of the ligand was found to be 1070 {mu}g of silver. The effects of various cationic interferences on the percent recovery of silver ion were studied. The method was successfully applied to the determination of silver ion in different samples, especially determination of ultra trace amount of silver in the presence of large amount of lead.

  12. SPECTROPHOTOMETRIC, ATOMIC ABSORPTION AND CONDUCTOMETRIC ANALYSIS OF TRAMADOL HYDROCHLORIDE

    Directory of Open Access Journals (Sweden)

    Sara M. Anis

    2011-09-01

    Full Text Available Six simple and sensitive spectroscopic and conductometric procedures (A-F were developed for the determination of tramadol hydrochloride. Methods A, B and C are based on the reaction of cobalt (II thiocyanate with tramadol to form a stable ternary complex, which could be measured by spectrophotometric (method A, atomic absorption (method B or conductometric (method C procedures. Methods D and E depend on the reaction of molybdenum thiocyanate with tramadol to form a stable ternary complex, measured by spectrophotometric means (method D or by atomic absorption procedures (method E, while method F depends on the formation of an ion pair complex between the studied drug and bromothymol blue which is extractable into methylene chloride. Tramadol hydrochloride could be assayed in the range of 80-560 and 40-–220 μg ml-1, 1-15 mg ml-1 and 2.5-22.5, 1.25-11.25 and 5-22 μg ml-1 using methods A,B,C,D,E and F, respectively. Various experimental conditions were studied. The results obtained showed good recoveries. The proposed procedures were applied successfully to the analysis of tramadol in its pharmaceutical preparations and the results were favorably comparable with the official method.

  13. Vacuum Ultraviolet Absorption Measurements of Atomic Oxygen in a Shock Tube

    Science.gov (United States)

    Meyer, Scott Andrew

    1995-01-01

    The absorption of vacuum ultraviolet light by atomic oxygen has been measured in the Electric Arc-driven Shock Tube (EAST) Facility at NASA-Ames Research Center. This investigation demonstrates the instrumentation required to determine atomic oxygen concentrations from absorption measurements in impulse facilities. A shock wave dissociates molecular oxygen, producing a high temperature sample of atomic oxygen in the shock tube. A probe beam is generated with a Raman-shifted ArF excimer laser. By suitable tuning of the laser, absorption is measured over a range of wavelengths in the region of the atomic line at 130.49 nm. The line shape function is determined from measurements at atomic oxygen densities of 3 x 10(exp 17) and 9 x 10(exp 17)/cu cm. The broadening coefficient for resonance interactions is deduced from this data, and this value is in accord with available theoretical models.

  14. Vacuum Ultraviolet Absorption Measurements of Atomic Oxygen in a Shock Tube

    Science.gov (United States)

    Meyer, Scott Andrew

    1995-01-01

    The absorption of vacuum ultraviolet light by atomic oxygen has been measured in the Electric Arc-driven Shock Tube (EAST) Facility at NASA-Ames Research Center. This investigation demonstrates the instrumentation required to determine atomic oxygen concentrations from absorption measurements in impulse facilities. A shock wave dissociates molecular oxygen, producing a high temperature sample of atomic oxygen in the shock tube. A probe beam is generated with a Raman-shifted ArF excimer laser. By suitable tuning of the laser, absorption is measured over a range of wavelengths in the region of the atomic line at 130.49 nm. The line shape function is determined from measurements at atomic oxygen densities of 3 x 10(exp 17) and 9 x 10(exp 17) cm(exp -3). The broadening coefficient for resonance interactions is deduced from this data, and this value is in accord with available theoretical models.

  15. Visualizing the Solute Vaporization Interference in Flame Atomic Absorption Spectroscopy

    Science.gov (United States)

    Dockery, Christopher R.; Blew, Michael J.; Goode, Scott R.

    2008-01-01

    Every day, tens of thousands of chemists use analytical atomic spectroscopy in their work, often without knowledge of possible interferences. We present a unique approach to study these interferences by using modern response surface methods to visualize an interference in which aluminum depresses the calcium atomic absorption signal. Calcium…

  16. Two-dimensional atom localization via probe absorption in a four-level atomic system

    Institute of Scientific and Technical Information of China (English)

    Wang Zhi-Ping; Ge Qiang; Ruan Yu-Hua; Yu Ben-Li

    2013-01-01

    We have investigated the two-dimensional (2D) atom localization via probe absorption in a coherently driven fourlevel atomic system by means of a radio-frequency field driving a hyperfine transition.It is found that the detecting probability and precision of 2D atom localization can be significantly improved via adjusting the system parameters.As a result,our scheme may be helpful in laser cooling or the atom nano-lithography via atom localization.

  17. Implementation of suitable flow injection/sequential-sample separation/preconcentration schemes for determination of trace metal concentrations using detection by electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry

    DEFF Research Database (Denmark)

    Hansen, Elo Harald; Wang, Jianhua

    2002-01-01

    Various preconditioning procedures encomprising appropriate separation/preconcentration schemes in order to obtain optimal sensitivity and selectivity characteristics when using electrothermal atomic absorption spectrometry (ETAAS) and inductively coupled plasma mass spectrometry (ICPMS) are pres......Various preconditioning procedures encomprising appropriate separation/preconcentration schemes in order to obtain optimal sensitivity and selectivity characteristics when using electrothermal atomic absorption spectrometry (ETAAS) and inductively coupled plasma mass spectrometry (ICPMS...

  18. Determination of absolute configuration using heavy atom based co-crystallization method: Halogen atom effects

    Science.gov (United States)

    Wang, Jian-Rong; Fan, Xiaowu; Ding, Qiaoce; Mei, Xuefeng

    2016-09-01

    Heavy atom (chloride, bromide, and iodide) based co-crystals for determination of absolute configuration (AC) for chiral molecules were synthesized and evaluated. Co-crystals of cholestanol and L-ascorbic acid were analysed and the effects and potential benefits of varying the heavy atom are discussed. Changing the halogen atoms (chloride, bromide, or iodide) affects the co-crystal formation, X-ray absorption, and anomalous dispersion, and hence the ability to determine AC.

  19. Graviton Emission and Absorption by Atomic Hydrogen

    CERN Document Server

    Rothman, S B T

    2006-01-01

    Graviton absorption cross sections and emission rates for hydrogen are calculated by both semi-classical and field theoretic methods. We point out several mistakes in the literature concerning spontaneous emission of gravitons and related phenomena, some of which are due to a subtle issue concerning gauge invariance of the linearized interaction Hamiltonian.

  20. Heralded single photon absorption by a single atom

    CERN Document Server

    Piro, Nicolas; Schuck, Carsten; Almendros, Marc; Huwer, Jan; Ghosh, Joyee; Haase, Albrecht; Hennrich, Markus; Dubin, Francois; Eschner, Jürgen

    2010-01-01

    The emission and absorption of single photons by single atomic particles is a fundamental limit of matter-light interaction, manifesting its quantum mechanical nature. At the same time, as a controlled process it is a key enabling tool for quantum technologies, such as quantum optical information technology [1, 2] and quantum metrology [3, 4, 5, 6]. Controlling both emission and absorption will allow implementing quantum networking scenarios [1, 7, 8, 9], where photonic communication of quantum information is interfaced with its local processing in atoms. In studies of single-photon emission, recent progress includes control of the shape, bandwidth, frequency, and polarization of single-photon sources [10, 11, 12, 13, 14, 15, 16, 17], and the demonstration of atom-photon entanglement [18, 19, 20]. Controlled absorption of a single photon by a single atom is much less investigated; proposals exist but only very preliminary steps have been taken experimentally such as detecting the attenuation and phase shift o...

  1. Study on organic extraction-flame atomic absorption spectrometry determination of gold in ore%有机萃取—火焰原子吸收法测定岩矿中金的探讨

    Institute of Scientific and Technical Information of China (English)

    张明祖; 覃路燕; 郭炳北

    2011-01-01

    在现有的有机萃取—原子吸收法测定岩矿中金的基础上,以乙酸丁酯、甲基异丁基甲酮(MIBK)为萃取剂进行比较,考察了两者对金的萃取性能.实验研究了KBr和Fe3+对有机萃取—原子吸收法测定金的影响,并对其他共存离子的干扰情况进行了探讨,优化了实验条件.%On the basis of the current organic extraction-flame atomic absorption spectrometry determination of gold in ores, butyl acetate and methyl isobutyl ketone (MIBK) were compared as extractants, and their extraction performance for gold was studied. The experiments on the effects of KBr and Fe3+ on the organic extraction-atomic ab-sorption spectrometry were carried out. The paper also investigated the interference of other coexist ions and optimized the experimental conditions.

  2. 国产原子吸收分光光度计测定硫化橡胶钴含量%Determination of Cobalt Content in Vulcanized Rubber by Domestic Atomic Absorption Spectrophotometer

    Institute of Scientific and Technical Information of China (English)

    王毅

    2014-01-01

    Since the adding of binder, vulcanized rubber always has cobalt. The conventional determination method of cobalt is the colorimetric method and the titration method. In this paper, application of domestic atomic absorption spectrophotometer TAS-990 in measuring cobalt in vulcanized rubber was explored;detail process of testing operation was described. The test results show that domestic TAS-990 atomic absorption spectrophotometer can be used for measuring cobalt content of vulcanized rubber;it is simple and easy to operate. Its test accuracy and sensitivity can be achieved to meet the requirements of chemical analysis test methods.%硫化橡胶中由于黏合剂的加入带入钴盐,传统的钴测定方法有比色法、滴定法等。探索使用国产原子吸收分光光度计 TAS-990进行测定,详细介绍了测试操作过程,通过试验验证结果可见,国产 TAS-990原子吸收分光光度计用于测定硫化橡胶中钴含量,操作方便简捷,测试准确度、灱敏度能够达到并满足化学分析试验方法要求。

  3. Determination of Cd,Cu,Pb,Fe,Zn in Bottled Drinking Water through Atomic Absorption Spectrometry Method%原子吸收光谱法对瓶装饮用水中Cd、Cu、Pb、Fe、Zn的分析

    Institute of Scientific and Technical Information of China (English)

    李帅; 沈祥森; 李勇

    2011-01-01

    10 different brands of commercial bottled drinking water for the experimental materials,using graphite furnace atomic absorption and flame atomic absorption spectrometry,the bottled water Cd、Cu、Pb、Fe、Zn five heavy metals were determined to understand the different brand bottled drinking water content of the five heavy metals.The results showed that:The whole bottled water content of the five heavy metals Cd、Cu、Pb、Fe、Zn are up to national standard requirements.%以10种不同品牌的市售瓶装饮用水为研究对象,运用石墨炉原子吸收法和火焰原子吸收法对其Cd、Cu、Pb、Fe、Zn5种重金属元素的含量进行分析,以了解不同品牌的瓶装饮用水中重金属元素的含量情况。研究结果表明:10种市售瓶装饮用水中的Cd、Cu、Pb、Fe、Zn 5种重金属含量均达到国标要求。

  4. Antimony quantification in Leishmania by electrothermal atomic absorption spectroscopy.

    Science.gov (United States)

    Roberts, W L; Rainey, P M

    1993-05-15

    Tri- and pentavalent antimony were quantified in Leishmania mexicana pifanoi amastigotes and promastigotes by atomic absorption spectroscopy with electrothermal atomization. Leishmania grown in axenic culture were treated with either potassium antimony tartrate [Sb(III)] or sodium stibogluconate [Sb(V)]. The parasites were collected, digested with nitric acid, and subjected to atomic absorption spectroscopy. The method was linear from 0 to 7 ng of antimony. The interassay coefficients of variation were 9.6 and 5.7% (N = 5) for 0.52 and 3.7-ng samples of leishmanial antimony, respectively. The limit of detection was 95 pg of antimony. The assay was used to characterize Sb(III) and Sb(V) influx and efflux kinetics. Influx rates were determined at antimony concentrations that produced a 50% inhibition of growth (IC50). The influx rates of Sb(V) into amastigotes and promastigotes were 4.8 and 12 pg/million cells/h, respectively, at 200 micrograms antimony/ml. The influx rate of Sb(III) into amastigotes was 41 pg/million cells/h at 20 micrograms antimony/ml. Influx of Sb(III) into promastigotes at 1 microgram antimony/ml was rapid and reached a plateau of 175 pg/million cells in 2 h. Efflux of Sb(III) and Sb(V) from amastigotes and promastigotes exhibited biphasic kinetics. The initial (alpha) half-life of Sb(V) efflux was less than 4 min and that of Sb(III) was 1-2 h. The apparent terminal (beta) half-lives ranged from 7 to 14 h.

  5. Fast emulsion-based method for simultaneous determination of Co, Cu, Pb and Se in crude oil, gasoline and diesel by graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Luz, Maciel S; Nascimento, Angerson N; Oliveira, Pedro V

    2013-10-15

    A method for the simultaneous determination of Co, Cu, Pb and Se in crude oil, gasoline and diesel samples using emulsion-based sampling and GF AAS is proposed. 400mg of sample was weighted in volumetric flask following the sequential addition of 125 µL of hexane and 7.5 mL of Triton X-100(®) (20% mv(-1)). Subsequently, the mixture was stirred in ultrasonic bath, during 30 min, before dilution to 25 mL with deionized water. Aliquots of 20 μL of reference solution or sample emulsion were co-injected into the graphite tube with 10 μL of 2 g L(-1) Pd(NO3)2. The pyrolysis and atomization temperatures were 1300°C and 2250°C, respectively. The limits of detection (n=10, 3σ) and characteristic masses were 0.02 μg g(-1) (0.32 μg L(-1)) and 18 pg for Co, 0.03 μg g(-1) (0.48 μg L(-1)) and 15 pg for Cu, 0.04 μg g(-1) (0.64 μg L(-1)) and 48 pg for Pb, and 0.11 μg g(-1) (1.76 μg L(-1)) and 47 pg for Se. The reliabilities of the proposed method for Co and Se were checked by SRM(®) 1634c Residual Oil analysis. The found values are in accordance to the SRM at 95% confidence level (Student's t-test). Each sample was spiked with 0.18 μg g(-1) of Co, Cu, Pb and Se and the recoveries varied from 92% to 116% for Co, 83% to 117% for Cu, 72% to 117% for Pb, and 82% to 122% for Se.

  6. Determination of Trace Cobalt in soil with graphite furnace atomic absorption spectrometry%石墨炉原子吸收光谱法测定土壤中痕量钴

    Institute of Scientific and Technical Information of China (English)

    张建军

    2013-01-01

    The nitric acid hydrofluoric acid hydrochloric acid mixed acid system of microwave digestion soil sample , method of Spectrophotometry for determination of Trace Cobalt in soil with graphite furnace atomic absorption .By the determination results of standard soil samples show that , the method is easy to operate , accurate , and reliable .%建立了硝酸-氢氟酸-盐酸混酸体系微波消解土壤样品,石墨炉原子吸收分光光谱法测定土壤中痕量钴的方法。通过对标准土样的测定结果表明,该方法容易操作、准确、可靠。

  7. Determination of Palladium in Resin by Lead Fire Assaying-Flame Atomic Absorption Spectrometric Method%铅试金富集-火焰原子吸收光谱法测定树脂中钯

    Institute of Scientific and Technical Information of China (English)

    王芳; 陈小兰; 林海山; 李小玲; 肖红新

    2013-01-01

    通过铅试金富集树脂中的钯并用银作钯灰吹保护,得到的银钯合粒用王水溶解,在5%的盐酸介质中,采用原子吸收光谱法测定钯,该法测钯的相对标准偏差RSD为0.53%,加标回收率在99.04%~100.10%之间。%Palladium in resin was enriched by lead assaying, using silver as a protective agent to produce silver-palladium alloy, and then the alloy was dissolved in aqua regia. Air acetylene flame atomic absorption spectrometric method was used to determinate palladium in 5%hydrochloric acid solution. The relative standard deviation (RSD) in determination of palladium is 0.53%and the recovery rate is between 99.04%~100.10%.

  8. Dispersive liquid-liquid microextraction based on solidification of floating organic drop for simultaneous separation/preconcentration of nickel, cobalt and copper prior to determination by electrothermal atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Mooud Amirkavei

    2013-01-01

    Full Text Available A dispersive liquid-liquid microextraction based on solidification of floating organic drop for simultaneous extraction of trace amounts of nickel, cobalt and copper followed by their determination with electrothermal atomic absorption spectrometry was developed. 300 µL of acetone and 1-undecanol was injected into an aqueous sample containing diethyldithiocarbamate complexes of metal ions. For a sample volume of 10 mL, enrichment factors of 277, 270 and 300 and detection limits of 1.2, 1.1 and 1 ng L-1 for nickel, cobalt and copper were obtained, respectively. The method was applied to the extraction and determination of these metals in different water samples.

  9. On-line preconcentration using a resin functionalized with 3,4-dihydroxybenzoic acid for the determination of trace elements in biological samples by thermospray flame furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lemos, Valfredo A. [Universidade Estadual do Sudoeste da Bahia, Laboratorio de Quimica Analitica, Campus de Jequie, 45206-190 Jequie, Bahia (Brazil)], E-mail: vlemos@uesb.br; Bezerra, Marcos A. [Universidade Estadual do Sudoeste da Bahia, Laboratorio de Quimica Analitica, Campus de Jequie, 45206-190 Jequie, Bahia (Brazil); Universidade Federal da Bahia, Instituto de Quimica, Campus Universitario Ondina, 40170-290 Salvador, Bahia (Brazil); Amorim, Fabio A.C. [Universidade Federal da Bahia, Instituto de Quimica, Campus Universitario Ondina, 40170-290 Salvador, Bahia (Brazil); Universidade Federal da Bahia, Instituto de Ciencias Ambientais e Desenvolvimento Sustentavel, Campus de Barreiras, 40805-100 Barreiras, Bahia (Brazil)

    2008-09-15

    In the present paper, an on-line preconcentration procedure for determination of cadmium, copper and zinc by thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) is proposed. Amberlite XAD-4 functionalized with 3,4-dihydroxybenzoic acid (XAD4-DHB) packed in a minicolumn was used as sorbent material. The metals were retained on the XAD-DHB resin, from which it could be eluted directly to the thermospray flame furnace system. The detection limits were 28 (Cd), 100 (Cu) and 77 ng L{sup -1} (Zn) for 60 s preconcentration time, at a sample flow rate of 7.0 mL min{sup -1}. Enrichment factors were 102, 91 and 62, for cadmium, copper and zinc, respectively. The procedure has been applied successfully to metal determination in biological standard reference materials.

  10. Ionic liquid-assisted multiwalled carbon nanotube-dispersive micro-solid phase extraction for sensitive determination of inorganic As species in garlic samples by electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Grijalba, Alexander Castro; Escudero, Leticia B.; Wuilloud, Rodolfo G.

    2015-08-01

    A highly sensitive dispersive micro-solid phase extraction (D-μ-SPE) method combining an ionic liquid (IL) and multi-walled carbon nanotubes (MWCNTs) for inorganic As species (As(III) and As(V)) species separation and determination in garlic samples by electrothermal atomic absorption spectrometry (ETAAS) was developed. Trihexyl(tetradecil)phosphonium chloride IL was used to form an ion pair with the arsenomolybdate complex obtained by reaction of As(V) with molybdate ion. Afterwards, 1.0 mg of MWCNTs was dispersed for As(V) extraction and the supernatant was separated by centrifugation. MWCNTs were re-dispersed with tetradecyltrimethylammonium bromide surfactant and ultrasound followed by direct injection into the graphite furnace of ETAAS for As determination. Pyrolysis and atomization conditions were carefully studied for complete decomposition of MWCNTs and IL matrices. Under optimum conditions, an extraction efficiency of 100% and a preconcentration factor of 70 were obtained with 5 mL of garlic extract. The detection limit was 7.1 ng L- 1 and the relative standard deviations (RSDs) for six replicate measurements at 5 μg L- 1 of As were 5.4% and 4.8% for As(III) and As(V), respectively. The proposed D-μ-SPE method allowed the efficient separation and determination of inorganic As species in a complex matrix such as garlic extract.

  11. Preparation of Modified Magnetic Nano-Fe3O4 Chitosan/ Graphene Oxide for the Preconcentration and Determination of Copper (П Ions in Biological and Environmental Water Samples Prior to Flame Atomic Absorption Spectrometry.

    Directory of Open Access Journals (Sweden)

    Mohammd Yari

    2016-06-01

    Full Text Available A simple, highly sensitive, accurate and selective method for determination of trace amounts of Cu2+in water samples .In this paper, chitosan grafted with graphene oxide sheets showed an increased surface area was used to encapsulate nano-Fe3O4 and produce a nano-Fe3O4-encapsulated-chitosan/graphene oxide sorbent based new sorbent was prepared. Flame atomic absorption spectrometer was utilized for determination of Cu2+.Some of the important parameters on the preconcentration and complex formation were selected and optimized. Under the optimized conditions the limit of detection (LOD and limit of quantification (LOQwere 0.30,0.750 and the proposed method has a good reproducibility 0.90% (RSD %.The enrichment factor was 200 and the percentage of recovery was in the range of 95-100% .The method was successfully applied to the recovery of Cu2+in different type of water samples. Graphene oxide and its derivates such as magnetic nano-Fe3O4-encapsulated-chitosan/graphene oxide in this study is full of potential to use as an excellent adsorbent in the extraction method like solid phase extraction(SPE and solid phase micro extraction(SPME. In the present study, we report the application of pre concentration techniques still continues increasingly for trace metal determinations by flame atomic absorption spectrometry (FAAS for quantification of Cu2+ in Formalin-fixed paraffin-embedded (FFPE tissues from Liver loggerhead turtles. This method exhibits the superiority in compared to the other adsorption reagents because of the fact that there is no necessity of any complexing reagent and optimum pH of solution presents in acidic media.

  12. 石墨炉原子吸收光谱法测定植物油中砷%Determination of arsenic in vegetable oil by graphite furnace atomic absorption spectrophotometry

    Institute of Scientific and Technical Information of China (English)

    俞涛; 蒋雪凤; 钟小伶

    2012-01-01

    Objective:To develop a method for the determination of arsenic in vegetable oil by graphite furnace a-tomic absorption spectrophotometry. Methods: After samples were digested with microwave, magnesium nitrate was added as matrix modifier and then determined by graphite furnace atomic absorption spectrometry. Results: The method had a linear relationship in the range of 0 μg/L ~ 20 μg/L ( r = 0. 9997) , and the detection limit was 0. 006 mg/kg, RSDs were between 2. 7% ~ 3. 2% ,the rate of recoveries were between 84. 7% ~99. 0% . Conclu-sion ; The method is simple, sensitive, reproducible and can be applicable to the determination of arsenic in vegeta-ble oil.%目的:建立检测植物油中砷含量的石墨炉原子吸收光谱方法.方法:样品经微波消化后,采用硝酸镁作为基体改进剂,石墨炉原子吸收光谱法测定.结果:方法线性范围为0 μg/L~ 20 μg/L,相关系数为0.9997,方法检出限为0.006 mg/kg,RSD为2.7%~3.2%,加标回收率为84.7%~99.0%.结论:本法简便、灵敏度高、重现性好,适用于植物油中砷的测定.

  13. Concentrations of As, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, and Zn in uruguayan rice determined by atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Mario E. Rivero Huguet

    2011-04-01

    Full Text Available The United Nations General Assembly declared the year 2004 the International Year of Rice and the concept "Rice is life". The largest nutritional problems occurring globally are protein-energy malnutrition, and Ca, Fe, I, Zn, and vitamin A deficiency. In this report, 49 rice samples (Oryza sativa L. were digested by dry ashing in order to determine As, Cd, Cr, and Pb by ETA-AAS; while Ca, Co, Cu, Fe, K, Mg, Mo, Mn, Na, Ni, and Zn were determined by FAAS; and Hg by CV-AAS using microwave-assisted decomposition. The following concentration ranges were obtained for Ca (9.1-15 mg/100 g, Cd (2.30-4.12 µg/kg, Co (41-60 µg/kg, Cu (1.33-180 mg/kg, Fe (4.41-7.15 mg/kg, K (167-217 mg/100 g, Mg (45-121 mg/100 g, Mo (0.52-0.97 mg/kg, Mn (5.45-25.4 mg/kg, Na (0.95-2.50 mg/100g, Ni (0.53-0.72 mg/kg, and Zn (5.86-12.6 mg/kg. Mean recoveries of elements from fortified rice were: 87±12% for As, 95.3±8.9% for Ca, 106.2±7.7% for Cd, 103.3±6.5% for Co, 89.4±8.1% for Cr, 99.3±4.6% for Cu, 103±10% for Fe, 96.3±9.3% for Hg, 95.4±12% for K, 98.3±8.0% for Mg, 93.4±7.8% for Mo, 95.3±9.9% for Mn, 89±12% for Na, 90.3±9.7% for Ni, 91.2±5.5% for Pb and 92.0±9.4% for Zn. The concentrations of the minerals and microelements studied fall within the typical range of rice grown around the world. Potassium was the most abundant mineral, followed by Mg and Ca; among microelements, the concentrations of Cu, Fe, Mo, Mn, Na, and Zn in rice were outstanding. It was also found that the milling process highly affects the K, Mg, Mn, Na, and Zn concentrations, while it has little influence on Ca, Co, Cu, and Fe. On the other hand, there is a loss of Ca, Fe, and Mn during the parboiling process. Recent studies have shown the potential to exploit the genetic variation of rice seeds with regard to the concentration of some minerals (Ca, Fe, Zn, etc. without affecting yield or adding new traits. All rice samples tested showed lower levels of As, Cd, Hg, and Pb in comparison

  14. Feasibility of filter atomization in high-resolution continuum source atomic absorption spectrometry

    Science.gov (United States)

    Heitmann, Uwe; Becker-Ross, Helmut; Katskov, Dmitri

    2006-03-01

    A prototype spectrometer for high-resolution continuum source atomic absorption spectrometry (HR-CS AAS), built at ISAS Berlin, Germany, was combined with a graphite filter atomizer (GFA), earlier developed at TUT, Pretoria, South Africa. The furnace and auto-sampler units from a commercial AA spectrometer, model AAS vario 6 (Analytik Jena AG, Jena, Germany), were employed in the instrument. Instead of conventional platform tube, the GFA was used to provide low measurement susceptibility to interferences and short determination cycle. The GFA was modified according to the design of the furnace unit and optimal physical parameters of its components (filter and collector) found. Afterwards, optimal GFA was replicated and tested to outline analytical performances of the HR-CS GFA AA spectrometer in view of prospects of multi-element analysis. In particular, reproducibility of performances, repeatability of analytical signals, lifetime, temperature limit and duration of the measurement cycle were examined, and elements available for determination justified. The results show that the peak area of the atomic absorption signal is reproduced in various GFA copies within ± 4% deviation range. The GFA can stand temperatures of 2800 °C with 6 s hold time for 55 temperature cycles, and 2700 °C (8 s) for about 200 cycles. Only the external tube is prone to destruction while the filter and collector do not show any sign of erosion caused by temperature or aggressive matrix. Analytical signals are affected insignificantly by tube aging. Repeatability of the peak area remains within 1.1-1.7% RSD over more than hundred determination cycles. Peak areas are proportional to the sample volume of injected organic and inorganic liquids up to at least 50 μL. The drying stage is combined with hot sampling and cut down to 15-20 s. The list of metals available for determination with full vapor release includes Al, Co, Cr, Ni, Pt as well as more volatile metals. Characteristic masses at

  15. Determination of spectrophotometric absorptivity by analytical ultracentrifugation

    Directory of Open Access Journals (Sweden)

    M Senthilraja

    2011-01-01

    Full Text Available Rapid determination of the absorptivity for a recombinant IgG monoclonal antibody using the Beckman equipped with both Raleigh interference and UV absorbance optical systems. The analytical ultracentrifuge data for determining spectrophotometric absorptivities is compared to experimental data from quantitative amino acid analysis and an enzymatic digestion method.

  16. A green and efficient procedure for the preconcentration and determination of cadmium, nickel and zinc from freshwater, hemodialysis solutions and tuna fish samples by cloud point extraction and flame atomic absorption spectrometry.

    Science.gov (United States)

    Galbeiro, Rafaela; Garcia, Samara; Gaubeur, Ivanise

    2014-04-01

    Cloud point extraction (CPE) was used to simultaneously preconcentrate trace-level cadmium, nickel and zinc for determination by flame atomic absorption spectrometry (FAAS). 1-(2-Pyridilazo)-2-naphthol (PAN) was used as a complexing agent, and the metal complexes were extracted from the aqueous phase by the surfactant Triton X-114 ((1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol). Under optimized complexation and extraction conditions, the limits of detection were 0.37μgL(-1) (Cd), 2.6μgL(-1) (Ni) and 2.3μgL(-1) (Zn). This extraction was quantitative with a preconcentration factor of 30 and enrichment factor estimated to be 42, 40 and 43, respectively. The method was applied to different complex samples, and the accuracy was evaluated by analyzing a water standard reference material (NIST SRM 1643e), yielding results in agreement with the certified values.

  17. Comparison of serum copper determination by colorimetric and atomic absorption spectrometric methods in seven different laboratories. The S.F.B.C. (Société Française de Biologie Clinique) Trace Element Group.

    Science.gov (United States)

    Arnaud, J; Chappuis, P; Zawislak, R; Houot, O; Jaudon, M C; Bienvenu, F; Bureau, F

    1993-02-01

    An interlaboratory collaborative trial was conducted on the determination of serum copper using two different methods, based on colorimetry (test combination Copper, Boehringer Mannheim, Mannheim, Germany) and flame atomic absorption spectrometry (FAAS). The general performance of the colorimetric method was below that of FAAS, except for sensitivity and linear range, as assessed by detection limit (0.44 versus 1.32 mumol/L) and upper limit of linearity (150 versus 50 mumol/L). The range of the between-run CVs and the recovery of standard additions were, respectively, 2.3-11.9% and 92-127% for the colorimetric method and 1.1-6.0% and 93-101% for the FAAS method. Interferences were minimal with both methods. The two techniques correlated satisfactorily (the correlation coefficients ranged from 0.945-0.970 among laboratories) but the colorimetric assay exhibited slightly higher results than the FAAS method. Each method was transferable among laboratories.

  18. Determination of Chromium in Metal Cluster Compounds by Atomic Absorption Spectrometry%原子吸收光谱法测定金属原子簇化合物中铬

    Institute of Scientific and Technical Information of China (English)

    唐森富

    2001-01-01

    报道了利用火焰原子吸收光谱法测定金属原子簇化合物中铬,用钠离子消除共存元素干扰。本法简便、快速,具有良好的准确度和精密度,相对标准偏差为0.60%—0.67%,回收率为100%—103%。%This paper described the determination of chromium in metal cluster compounds by flame atomic absorption spectrometry.The coexisting element interference was eliminated by sodium ion.The method is simple and rapid.The relative standard deviation is 0.60%—0.67%.The recovery rate is 100%—103%.

  19. Combined discrete nebulization and microextraction process for molybdenum determination by flame atomic absorption spectrometry (FAAS); Avaliacao da combinacao da nebulizacao discreta e processos de microextracao aplicados a determinacao de molibdenio por espectrometria de absorcao atomica com chama (FAAS)

    Energy Technology Data Exchange (ETDEWEB)

    Oviedo, Jenny A.; Jesus, Amanda M.D. de; Fialho, Lucimar L.; Pereira-Filho, Edenir R., E-mail: erpf@ufscar.br [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Quimica

    2014-04-15

    Simple and sensitive procedures for the extraction/preconcentration of molybdenum based on vortex-assisted solidified floating organic drop microextraction (VA-SFODME) and cloud point combined with flame absorption atomic spectrometry (FAAS) and discrete nebulization were developed. The influence of the discrete nebulization on the sensitivity of the molybdenum preconcentration processes was studied. An injection volume of 200 μ resulted in a lower relative standard deviation with bo