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1.
Calibration possibilities and modifier use in ETV ICP OES determination of trace and minor elements in plant materials 总被引:2,自引:0,他引:2
Albena Detcheva Peter Barth Juergen Hassler 《Analytical and bioanalytical chemistry》2009,394(5):1485-1495
The possibilities for universal calibration based on multi-element aqueous standard solutions and graphite laboratory reference
materials (graphite standards) for the electrothermal vaporization inductively coupled plasma optical emission spectrometric
(ETV ICP OES) determination of Al, B, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, P, Pb, S, Sr, Ti, V, and Zn in plant materials were
investigated. A commercially available state-of-the-art ETV device was coupled with an Echelle ICP spectrometer equipped with
a charge-injection-device (CID) camera for spectral detection. The transition area between transport tube and ETV graphite
tube and the gas streams for inner gas, bypass gas, and modifier gas were optimized to achieve best transport efficiencies.
The influence of four gaseous modifiers (CCl4, CHCl3, CCl2F2, and C3H8) added to the inner gas was studied. Five reference materials (RM P-Alfalfa, Lucerne; NIES CRM No.9 “Sargasso”; CTA-VTL-2
Virginia Tobacco Leaves; NIST SRM 1515 Apple Leaves; IAEA-V-10 Hay Powder) were used for method validation. If certified reference
materials are not available, calibration against graphite standards or dried aqueous standard solutions is possible. Three
carbonization procedures as sample pretreatment for the plant materials were investigated.
Figure Picture of the ETV system (sample changer and graphite-tube furbace) used in this work
Presented at the European Symposium on Atomic Spectrometry (ESAS) September 28-October 1, 2008, Weimar, Germany. 相似文献
2.
Two digestion-free methods for trace analysis of boron nitride based on graphite furnace atomic absorption spectrometry (GFAAS) and electrothermal vaporization inductively coupled plasma spectrometry optical emission (ETV-ICP-OES) using direct solid sampling have been developed and applied to the determination of Al, Ca, Cr, Cu, Fe, Mg, Mn, Si, Ti and Zr in four boron nitride materials in concentration intervals of 1–23, 54–735, 0.05–21, 0.005–1.3, 1.6–112, 4.5–20, 0.03–1.8, 6–46, 38–170 and 0.4–2.3 μg g− 1, respectively. At optimized experimental conditions, with both methods, effective in-situ analyte/matrix separation was achieved and calibration could be performed using calibration curves measured with aqueous standard solutions. In solid sampling GFAAS, before sampling, the platform was covered with graphite powder and, for determination of Si, also the Pd/Mg(NO3)2 modifier was used. In the determination of all analyte elements by solid sampling ETV-ICP-OES, Freon R12 was added to argon carrier gas. For solid sampling GFAAS and ETV-ICP-OES, the achievable limits of detection were within 5 (Cu)–130 (Si) ng g− 1 and 8 (Cu)–200 (Si) ng g− 1, respectively. The results obtained by these two methods for four boron nitride materials of different purity grades are compared each with the other and with those obtained in analysis of digests by ICP-OES. The performance of the two solid sampling methods is compared and discussed. 相似文献
3.
Lúcia Felicidade Dias Tatiana D. Saint'Pierre Sandra M. Maia Mrcia A. Mesquita da Silva Vera L. A. Frescura Bernhard Welz Adilson J. Curtius 《Spectrochimica Acta Part B: Atomic Spectroscopy》2002,57(12):2003-2015
A procedure for the determination of As, Pb, Se and Sn in sediment slurries by electrothermal vaporization inductively coupled plasma mass spectrometry is proposed. The slurry, 1 mg ml−1, is prepared by mixing the sample ground to a particle size 50 μm with 5% v/v nitric and 1% v/v hydrofluoric acids in an ultrasonic bath. The slurry was homogenized with a constant flow of argon in the autosampler cup, just before transferring an aliquot to the graphite furnace. The tube was treated with Ru as a permanent modifier, and an optimized mass of 1 μg of NaCl was added as a physical carrier. The pyrolysis temperature was optimized through pyrolysis curves, and a compromised temperature of 800 °C was used; the vaporization temperature was 2300 °C. The effect of different acid concentrations in the slurry on the analyte signal intensities was also evaluated. The accuracy of the method was assured by the analysis of certified reference sediments MESS-2, PACS-2 and HISS-1 from the National Research Council Canada, SRM 2704 and SRM 1646a from the National Institute of Standards and Technology and RS-4 from a round robin test, using external calibration with aqueous standards prepared in the same medium as the slurries. The obtained concentrations were in agreement with the certified values according to the Student's t-test for a confidence level of 95%. The detection limits in the samples were: 0.17 μg g−1 for As; 0.3 μg g−1 for Pb; 0.05 μg g−1 for Se and 0.28 μg g−1 for Sn. The precision found for the different sediment samples, expressed as R.S.D. was 1–8% for As, 2–9% for Pb, 6–12% for Se and 3–8% for Sn (n=5). 相似文献
4.
Tatiana D. Saint'Pierre Lúcia Felicidade Dias Dirce Pozebon Ricardo Q. Auclio Adilson J. Curtius Bernhard Welz 《Spectrochimica Acta Part B: Atomic Spectroscopy》2002,57(12):1991-2001
Trace metals in fuels, except in the case of additives, are usually undesirable and normally they occur in very low concentrations in gasoline, requiring sensitive techniques for their determination. Coupling of electrothermal vaporization with inductively coupled plasma mass spectrometry minimizes the problems related to the introduction of organic solvents into the plasma. Furthermore, sample preparation as oil-in-water emulsions reduces problems related to gasoline analysis. In this work, a method for determination of Cu, Mn, Ni and Sn in gasoline is proposed. Samples were prepared by forming a 10-fold diluted emulsion with a surfactant (Triton X-100), after treatment with concentrated HNO3. The sample emulsion was pre-concentrated in the graphite tube by repeated pipetting and drying. External calibration was used with aqueous standards in a purified gasoline emulsion. Six samples from different gas stations were analyzed, and the analyte concentrations were found to be in the μg l−1 range or below. The limits of detection were 0.22, 0.02, 0.38 and 0.03 μg l−1 for Cu, Mn, Ni and Sn, respectively. The accuracy of the method was estimated using a recovery test. 相似文献
5.
In this review, the literature on the subject of electrothermal vaporization-inductively coupled plasma-mass spectrometry (ETV-ICP-MS) published during the last decade is reviewed with a double purpose: an evaluation of the possibilities of this technique for dealing with very challenging analytical applications on the one hand, and the establishment of a reference guide for method development in ETV-ICP-MS on the other. First, a brief introduction, pointing out the milestones in the development of the technique will provide the reader with a better understanding of the present situation of ETV-ICP-MS and its future perspective. After a section on the basic processes occurring in the furnace and during analyte transport, a guide for method development for challenging analytical applications is proposed, based on the existing literature. Next, the latest contributions in the main application areas of the field are reviewed, with special attention to the most challenging ones: i.e. speciation, “thermal” resolution, enabling complex matrixes to be analyzed and spectral overlap to be avoided, and the direct analysis of slurries and solid samples. Finally, the advantages obtained by coupling an ETV unit to newer types of ICP-MS instrumentation, equipped with collision/reaction cells, time-of-flight (TOF) or sector field (SF) spectrometers, are also discussed. 相似文献
6.
A total of 117 honeysuckle (Lonicera japonica Thunb.) samples from four major regions of production in China, including Fengqiu in Henan, Pingyi in Shandong, Julu in Hebei, and Xiushan in Chongqing, were analyzed to determine their geographical origin. δ13C, δ15N, and δ18O values were determined by isotope ratio mass spectrometry (IRMS), and the contents of 18 elements (Fe, Mn, Cu, Zn, K, Ca, Mg, Pb, Cd, Cr, As, Hg, Se, Sr, Ni, Co, B, and Mo) were measured by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). Multivariate statistical analysis by analysis of variance (ANOVA), principal component analysis (PCA), and linear discriminant analysis (LDA) were performed. The results showed that there were very significant differences in the stable isotope ratios and elemental concentrations in honeysuckle based on geographical origin, with plants from each region having a unique fingerprint. Discriminant functions were established to distinguish the origin of honeysuckle using suitable indicators including Cd, Cr, As, Hg, Se, Co, Ni, Sr, Fe, δ13C, δ15N, and δ18O. Cross-validated cases of 95.7% were correctly classified. 相似文献
7.
Chen Shizhong Lu Dengbo Hu Zhixiong Wang Zhan 《International journal of environmental analytical chemistry》2013,93(7):493-501
A procedure for the determination of trace elements in human hair has been proposed by electrothermal vaporization inductively coupled plasma optical emission spectrometry (ETV-ICP-OES) with slurry sampling. Slurry was prepared by immersing human hair with conc. HNO3 and then adding a polytetrafluoroethylene (PTFE) slurry, which was used as a chemical modifier for the improvement of vaporization characteristic of analyte. The slurry was homogenized with an ultrasonic vibrator before the measurement. The vaporization behaviour of the analytes in slurry and solution and the main influence factors for the determination were studied with the addition of PTFE systematically. Detection limits for this method varied from 0.033?µg?g?1 (Cu) to 3.21?µg?g?1 (Zn) with the relative standard deviations (RSDs) of 2.8–7.1%. The proposed method was successfully applied for the determination of trace elements (Cu, Mn, Cr, Fe, Zn, Cd and Pb) in human hair with minimum chemical pretreatment and aqueous calibration. The accuracy was checked by comparing the results of this method with those using pneumatic nebulization (PN) ICP-OES after a conventional acid decomposition of the same sample. In addition, the standard reference material of human hair (GBW 07601) was analysed with good agreement between the results from the proposed method and the certified values. 相似文献
8.
Ndio Oleszczuk Jacira T. Castro Mrcia M. da Silva Maria das Graas A. Korn Bernhard Welz Maria Goreti R. Vale 《Talanta》2007,73(5):862-869
A method has been developed for the determination of cobalt, copper and manganese in green coffee using direct solid sampling electrothermal atomic absorption spectrometry (SS-ET AAS). The motivation for the study was that only a few elements might be suitable to determine the origin of green coffee so that the multi-element techniques usually applied for this purpose might not be necessary. The three elements have been chosen as test elements as they were found to be significant in previous investigations. A number of botanical certified reference materials (CRM) and pre-analyzed samples of green coffee have been used for method validation, and inductively coupled plasma optical emission spectrometry (ICP OES) after microwave-assisted acid digestion of the samples as reference method. Calibration against aqueous standards could be used for the determination of Mn and Co by SS-ET AAS, but calibration against solid CRM was necessary for the determination of Cu. No significant difference was found between the results obtained with the proposed method and certified or independently determined values. The limits of detection for Mn, Cu and Co were 0.012, 0.006 and 0.004 μg g−1 using SS-ET AAS and 0.015, 0.13 and 0.10 μg g−1 using ICP OES. Seven samples of Brazilian green coffee have been analyzed, and there was no significant difference between the values obtained with SS-ET AAS and ICP OES for Mn and Cu. ICP OES could not be used as a reference method for Co, as essentially all values were below the limit of quantification of this technique. 相似文献
9.
Utilising extremely different vaporisation properties of boron compounds, the determination procedures of volatile boric acid and total boron using tungsten boat furnace (TBF) ICP-MS and TBF-ICP-AES have been investigated. For the determination of volatile boric acid by TBF-ICP-MS, tetramethylammonium hydroxide (TMAH, Me4NOH) was used as a chemical modifier to retain it during drying and ashing stages. As for the total boron, not only non-volatile inorganic boron such as boron nitride (BN), boron carbide (B4C), etc. but also boric acid (B(OH)3) was decomposed by a furnace-fusion digestion with NaOH to produce sodium salt of boron, a suitable species for the electrothermal vaporisation (ETV) procedure. The proposed method was applied to the analysis of various standard reference materials. The analytical results for various biological and steel samples are described. 相似文献
10.
Two different approaches were used to improve the capabilities of solid sampling (SS) electrothermal vaporization (ETV) coupled to inductively coupled plasma optical emission spectrometry (ICP-OES) for the direct analysis of powdered rice. Firstly, a cooling step immediately before and after the vaporization step in the ETV temperature program resulted in a much sharper analyte signal peak. Secondly, point-by-point internal standardization with an Ar emission line significantly improved the linearity of calibration curves obtained with an increasing amount of rice flour certified reference material (CRM). Under the optimized conditions, detection limits ranged from 0.01 to 6 ng g−1 in the solid, depending on the element and wavelength selected. The method was validated through the quantitative analysis of corn bran and wheat flour CRMs. Application of the method to the multi-elemental analysis of 4-mg aliquots of real organic long grain rice (white and brown) also gave results for Al, As, Co, Cu, Fe, Mg, Se, Pb and Zn in agreement with those obtained by inductively coupled plasma mass spectrometry following acid digestion of 0.2-g aliquots. As the analysis takes roughly 5 min per sample (2.5 min for grinding, 0.5–1 min for weighing a 4-mg aliquot and 87 s for the ETV program), this approach shows great promise for fast screening of food samples. 相似文献
11.
Maria Goreti R. Vale Bernhard Welz 《Spectrochimica Acta Part B: Atomic Spectroscopy》2002,57(12):1821-1834
The literature on the determination of Tl in environmental samples using electrothermal atomization (ETA) and vaporization (ETV) techniques has been reviewed with special attention devoted to potential interferences and their control. Chloride interference, which is due to the formation of the volatile monochloride in the condensed phase, is the most frequently observed problem. Due to its high dissociation energy (88 kcal/mol), TlCl is difficult to dissociate in the gas phase and is easily lost. The best means of controlling this interference in ETA is atomization under isothermal conditions according to the stabilized temperature platform furnace concept, and the use of reduced palladium as a modifier. An alternative approach appears to be the ‘fast furnace’ concept, wherein both the use of a modifier and the pyrolysis stage are omitted. This concept requires an efficient background correction system, and high-resolution continuum-source atomic absorption spectrometry (HR-CS AAS) appears to offer the best results. This chloride interference can also cause significant problems when ETV techniques are used. Among the spectral interferences found in the determination of thallium are those due to Pd, the most efficient modifier, and Fe, which is frequently found at high concentrations in environmental samples. Both interferences are due to nearby atomic lines, and are observed only when deuterium background correction and relatively high atomization temperatures are used. A more serious spectral interference is that due to the molecular absorption spectrum of SO2, which has a maximum around the Tl line and exhibits a pronounced rotational fine structure. HR-CS AAS again showed the best performance in coping with this interference. 相似文献
12.
《Analytical letters》2012,45(17):2729-2746
Abstract The validation of a method for the determination of total chromium in Fischer-344 rat feces by inductively coupled plasma optical emission spectrometry following a rapid, atmospheric-pressure microwave digestion is described. The performance of the method was evaluated over the concentration range of 5.00 to 200 µg Cr/g feces. Data for method linearity, accuracy, precision, digest stability, and storage stability are presented along with limit of detection and limit of quantitation data. Data from a cross-validation method for B6C3F1 mouse feces are also presented. Following validation, the method was applied to analyze samples collected in support of two chronic toxicological investigations. 相似文献
13.
A method was developed for the determination of As, Cd, Pb and Tl by electrothermal vaporization inductively coupled plasma
mass spectrometry (ETV-ICP-MS) with slurry sample introduction using certified reference coal samples. The 75As, 111Cd, 208Pb and 205Tl isotopes were monitored, considering the lower probabilities of these isotopes in suffering interferences. The carrier
and modifier effect of Ru added in solution was evaluated, demonstrating that sensitivity for all elements is considerably
improved by the addition of 15 μg of Ru to each individual measurement. This confirms its ability to act as a physical carrier
particularly for the analytes in aqueous solution. Pyrolysis and vaporization temperatures of 500 and 2500 °C, respectively,
were selected after optimization for aqueous solutions and for coal slurries. Similarly, the carrier gas flow rate was optimized
as 1.1 L min−1. After optimization of the operational parameters, the determination of the four elements in six certified reference coal
samples was carried out by external calibration against aqueous standards in 5% v/v HNO3, resulting in good agreement between the certified or given values and the determined ones. For Tl, due to the absence of
certified values, a comparison was established considering previously published data using solid sampling high-resolution
continuum source graphite furnace atomic absorption spectrometry. Detection limits (μg g−1) of 0.1, 0.004, 0.045 and 0.001 were achieved for As, Cd, Pb and Tl, respectively, and the precision was typically better
than 10%. 相似文献
14.
Slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry for the determination of As and Se in soil and sludge 总被引:2,自引:0,他引:2
Slurry sampling electrothermal vaporization (ETV) inductively coupled plasma mass spectrometry (ICP-MS) has been applied to determine As and Se in soil and sludge samples. The influences of instrument operating conditions and slurry preparation on the ion signals were reported. Pd and ascorbic acid were used as mixed modifiers to enhance the ion signals. The effectiveness of ETV sample introduction technique for alleviating various spectral interferences in ICP-MS analysis has been demonstrated. This method has been applied to determine As and Se in NIST SRM 2709 San Joaquin soil reference material and NIST SRM 2781 domestic sludge reference material and a farmland soil sample collected locally. Since the sensitivities of As and Se in slurry solution and aqueous solution were different, analyte addition technique was used to determine As and Se in these samples. The As and Se analysis results of the reference materials agreed with the certified values. The precision between sample replicates was better than 5% for all determinations. The method detection limit estimated from analyte addition curves was about 0.03 and 0.02 μg g−1 for As and Se, respectively, in original soil and sludge samples. 相似文献
15.
Summer N. Hanna Clifton P. Calloway Jr. Jason D. Sanders Ronald A. Neslon Jamaal Cox Bradley T. Jones 《Microchemical Journal》2011,99(2):165-169
A new compact, aluminum electrothermal vaporization cell was constructed for inductively coupled plasma-optical emission spectrometry analysis. This cell is compact enough to fit within the space occupied by the spray chamber and fits directly to the quartz torch without extraneous tubing through the use of a simple Compression fitting. Sample volumes as low as 10 μL were analyzed with an automated control program for efficient vaporization. Twelve elements were analyzed utilizing a time resolved acquisition method so that real-time data could be generated over a period of 10 s with an average improvement factor of 14 for elements over a wavelength range of 193–445 nm. 相似文献
16.
为提高土壤多元素同时检测的效率,采用超级微波消解-电感耦合等离子体发射光谱法测定土壤中钾、钠、钙、镁、铜、铁、锰、锌、磷、硫、硼、砷、镉、铬、铅、钴、镓、锂等18种元素含量。比较了超级微波消解、常规微波消解和电热板消解的处理效果,采用超级微波消解法对样品进行前处理,并优化了消解条件。在最优条件下,各元素的检出限在0.05~20 mg/kg,加标回收率在86.2%~107.5%,RSD在0.1%~3.0%,方法准确度及精密度可以满足多元素同时测定的需求,且该方法具有简单、快速、成本低、用酸量少、重现性好等特点。 相似文献
17.
Yu Min Park Ji Yeon Choi Eun Yeong Nho Cheong Mi Lee In Min Hwang Naeem Khan 《Analytical letters》2019,52(6):1018-1030
This study determined the concentration of eight macroelements (Na, K, Mg, P, S, Ca, Fe, Zn) and nineteen trace elements (Li, Be, Cr, Mn, Co, Ni, V, Cu, Ga, Se, Rb, Sr, In, Sn, Cs, Ba, Tl, Bi, U) in commonly consumed canned marine products from South Korea. The samples were wet-digested using nitric acid and hydrogen peroxide by a microwave system and analyzed for macroelements using inductively coupled plasma—optical emission spectrometry (ICP-OES) and for trace elements by inductively coupled plasma—mass spectrometry (ICP-MS). The analytical methods were validated by the correlation coefficients, limits of detection and quantification, correlation variance, spiking recovery tests, and analyzing a NIST 1566?b oyster tissue certified reference material. The concentrations of macro and trace elements varied among the canned marine products. The macroelements were present in the order of Na?>?K?>?P?>?S> Mg?>?Ca?>?Fe?>?Zn. In general, the concentrations of macro and trace elements were within the specified limits of Food and Nutrition Board, Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives, and Ministry of Food and Drug Safety, Korea. The results suggest that the analyzed canned marine products are safe in terms of the analyzed elements and their consumption therefore does not cause any threat to human health. 相似文献
18.
本文探讨了土壤中汞的ICP发射光谱测定法。实验中使用的介质有HCl,HNO_3,H_2SO_4和HClO_4,还原剂是SnCl_O或NaBH_4。通过实验值与推荐值的对照,验证了方法的可靠性。本法灵敏度高,干扰少,动态范围宽。在1%HNO_3溶液中所达到的检测限分别为0.7和0.09ppb。 相似文献
19.
Sang-Deuk Kim Jae-Min Lim Won Lee Young-Sang Kim Sang-Ho Nam Yong-Ill Lee 《Microchemical Journal》2004,78(2):127-134
A novel method for the determination of trace elements in microliter samples using the tantalum filament electrothermal vaporization/low-pressure inductively coupled plasma (ETV/LP-ICP) atomic emission spectrometry has been developed. An improved tantalum filament ETV was directly coupled with LP-ICP system for efficient vaporization of microliter samples and further quantitative analysis. The experimental parameters including ETV current, rf power and mass flow rate of argon carrier gas were optimized using the copper emission signal produced by 5 μl of standard solution (5 μg/ml). Under the optimized condition, the analytical performances including linearity, precision and detection limit for the developed system were investigated. Absolute detection limits in the range of 22–391 pg for selected eight elements (Fe, Cu, Cr, Mn, Pb, K, Zn and Mg) were obtained with satisfactory precision (<8.9% RSD). The feasibility of the developed system has been demonstrated by analyzing wheat gluten NIST standard sample. 相似文献
20.
用电感耦合等离子体发射光谱仪(ICP)测定了湛江地区产的中药茅根微量元素的含量。结果表明,其钙、镁、铁、锌等元素的含量都比较丰富,测定方法的相对标准偏差为0.12%~4.03%,回收率为97.0%~102.0%,本法简便、快速,具有较高的准确性和重现性,适用于实际分析。 相似文献