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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Vanadium

  • IUPAC Name: vanadium
  • Molecular Formula: V
  • CAS Registry Number: 7440-62-2
  • InChI: InChI=1S/V
  • InChI Key: LEONUFNNVUYDNQ-UHFFFAOYSA-N

@ ChemSpider@ NIST@ PubChem

Citations 63

"On-line Preconcentration System For Vanadium Determination In Drinking Water Using Flow Injection-inductively Coupled Plasma Atomic Emission Spectrometry"
Anal. Chim. Acta 2000 Volume 420, Issue 1 Pages 73-79
R. G. Wuilloud, J. A. Salonia, J. A. Gásquez, R. A. Olsina and L. D. Martinez

Abstract: An on-line vanadium a pre-concentration and determination system implemented with inductively coupled plasma atomic emission spectrometry (ICP-AES) associated to low flow injection (FI) was studied. For the retention of vanadium, 2- (5-Bromo-2-pyridylazo)-5-diethylaminophenol (5-Br- PADAP) and Amberlite XAD-7 were used, at pH 3.7. The vanadium was removed from the mcirocolumn in countercurrent with nitric acid. An enrichment factor (EF) of 75 was obtained. The detection limit value for the pre-concentration of 50 mL of aqueous solution of vanadium was 0.04 µgl-1. The precision for 10 replicate determinations at the 5 µg L-1 vanadium levels was 2.5% relative standard deviation (R.S.D), calculated with the peak heights obtained. The calibration graph using the pre-concentration system for vanadium was linear with a correlation coefficient of 0.9996 at levels near the detection limited up to at least 50 µgl-1. The method was successfully applied to the determination of vanadium in drinking water samples.
Water NIST 1640 Spectrophotometry Preconcentration Extraction Amberlite Reference material Optimization

"Determination Of Trace Levels Of Dissolved Vanadium In Seawater By Use Of Synthetic Complexing Agents And Inductively Coupled Plasma-atomic Emission Spectroscopy (ICP-AES)"
Anal. Bioanal. Chem. 2002 Volume 374, Issue 5 Pages 873-878
Ghiasse Abbasse, Baghdad Ouddane, Jean Claude Fischer

Abstract: In the determination of traces of dissolved vanadium in complex matrices such as seawater, separation and enrichment from the matrix is of special importance. A wide variety of methods has been proposed for pre-concentration, depending to the nature of samples and the methods to be used for measurement. Among these methods separation techniques based on sorption on to chelating resins seem convenient, rapid and capable of achieving a high concentration factor. The methods proposed in this paper are based on the transformation of all dissolved vanadium species in seawater into organic complexes by use of synthetic complexing agents such as dithizone, luminol, or 8-hydroxyquinoline; the resulting vanadium-organic complexes were sorbed on to a C-18 column at a flow rate of 5 mL min^-1. The vanadium sorbed on the C-18 columns was then stripped by use of nitric acid (2 mol L^-1) and analyzed by inductively coupled plasma-atomic emission spectroscopy, ICP-AES. This method was optimized and use of other chelating resins, such as chelamine, chelex-100, and immobilized 8-hydroxyquinoline and was compared by passing seawater samples directly over the resins. The experimental conditions (pH, acid used for elution, and contact time between the liquid sample and the resin) were optimized. The results were compared for all the resins used and were indicative of excellent and coherent reproducibility.
Sea Spectrophotometry 8-Hydroxyquinoline Chelex C18 Immobilized reagent Optimization Preconcentration Chelamine

"On-line Electrolytic Dissolution Of Alloys In Flow Injection Analysis - Determination Of Iron, Tungsten, Molybdenum, Vanadium And Chromium In Tool Steels By Inductively Coupled Plasma Atomic Emission Spectrometry"
Anal. Chim. Acta 2000 Volume 405, Issue 1-2 Pages 213-219
Ana Paula G. Gervasio, Gilmara C. Luca, Amauri A. Menegário, Boaventura F. Reis and Henrique Bergamin Filho

Abstract: A flow injection procedure involving on-line anodic electrolytic dissolution for Fe, W, Mo, V and Cr determination in tool steels by inductively coupled plasma atomic emission spectrometry is proposed. The sample is dissolved in an electrolytic cell coupled to the spectrometer nebulizer and a 1.5 mol L-1 HNO3 electrolytic solution is used to close the electric contact between electrodes. The system permits direct analysis of 30 solid samples per hour (150 determinations) and yields results with a relative standard deviation (r.s.d) lower than 5 % (n = 5). The applicability of the procedure was verified by analyzing tool steels samples and accuracy was assessed by comparison with a conventional sample dissolution procedure.
Alloy Spectrophotometry Electrochemical dissolution

"Determination Of Arsenic And Vanadium In Airborne Related Reference Materials By Inductively Coupled Plasma-mass Spectrometry"
Anal. Chim. Acta 1999 Volume 392, Issue 2-3 Pages 299-306
Chu-Fang Wang, C. Y. Chang, C. J. Chin and L. C. Men

Abstract: This study investigated sample digestion techniques and instrumental interference in determining As and V in airborne related reference materials using inductively coupled plasma mass spectrometry (ICP-MS). Four reference materials, NIST SRM 1648 urban particulate matter, BCR Reference Material No. 176 city waste incineration ash, NIST SRM 2709 San Joaquin soil, and NIST SRM 1633b coal fly ash were dissolved by acid mixture high-pressure bomb digestion. A HNO3+H2O2+HF mixed acid digestion with a low temperature evaporation procedure is proposed as an effective sample pretreatment method for the determination of As in all samples. The addition of HF is required especially for dissolving geologically originated samples such as soil or dust. It was found that, with the proposed digestion procedure, the determinations of V are still unacceptable for highly chlorinated samples when using quadrupole ICP-MS. It was also proved that sector-field ICP-MS is sufficiently sensitive for the determination of V, and can be utilized as a valid tool to investigate the amount and direction of biased results obtained from ICP-MS.
NIST 1648 BCR 176 NIST 1633 NIST 2709 Mass spectrometry Optimization Interferences Reference material

"Flow Injection Determination Of Trace Vanadium With Catalytic Photometric Detection"
Anal. Chim. Acta 1980 Volume 119, Issue 2 Pages 389-392
Takeshi Yamane, Tsutomu Fukasawa

Abstract: A catalytic photometric detection system based on the chromotropic acid-bromate reaction is adapted to a flow injection system for the rapid, simple and sensitive determination of vanadium. Vanadium in the range 0.3-4.8 ng (10-160 ppb) can be determined at a rate of ~60 samples per hour.
Spectrophotometry Catalysis

"Flow Injection Spectrophotometric Determination Of Trace Vanadium Based On Catalysis Of The Gallic Acid Bromate Reaction"
Anal. Chim. Acta 1986 Volume 183, Issue 1 Pages 269-274
Tsutomu Fukasawa, Susumu Kawakubo and Akihiro Unno

Abstract: Changes in reactant concentration, temp., pH and residence time can be used to alter the rectilinear calibration ranges and sensitivity for V. With 1.76 M BrO3- and 0.06 M gallic acid at pH 3.8, each at 0.5 mL min-1 in a flow injection system, 0.2 to 20 ng of V (20 µL injections) can be determined at 30°C. Oxidized gallic acid is detected at 380 nm. At 65°C and with 0.5 M BrO3-, 0.05 to 4 ng of V can be determined, with coefficient of variation ~5% for 0.6 ng of V. The tolerances for Al(III), Fe(III), Mo(VI) and I- are 10, 10, 50 and 200 ng, respectively, for the determination of 1 ng of V at 65°C and 2000, 200, 500 and 500 ng, respectively, at 30°.
Spectrophotometry Catalysis Heated reaction Interferences

"Online Separation And Preconcentration In Flow Injection Analysis"
Anal. Chim. Acta 1988 Volume 214, Issue 1-2 Pages 41-55
Zhaolun Fang, Zhaohai Zhu, Suchun Zhang, Shukun Xu, Lei Guo and Lijing Sun

Abstract: A review is presented of developments in flow injection analysis that involve separation and pre-concentration. by gas diffusion, ion exchange or liquid - liquid extraction. Several inorganic illustrations of each principle are given, mainly of their use as a preliminary stage before determination by AAS. (44 references).
Ion exchange Spectrophotometry Spectrophotometry Spectrophotometry Spectrophotometry Sample preparation Extraction Gas diffusion Preconcentration Review

"Segmental Flow Injection Analysis: Device And Applications"
Anal. Chim. Acta 1990 Volume 238, Issue 1 Pages 183-190
Li-Ching Tian, Xiao-Ping Sun, Yi-Yun Xu and Zheng-Liang Zhi

Abstract: The cited system possesses features of both flow injection and continuous-flow analysis. The sample zone is segmented by only two air bubbles and contained a valve designed so that sample and bubbles could be quantitatively injected into the carrier stream. The system provided residence times of >10 min at temperature up to 95°C without loss of peak height or sampling frequency, and owing to good reproducibility, analysis could be carried out before the equilibrium state was reached. The method was demonstrated by the determination of amino-acids in tea with the ninhydrin reagent, giving recoveries from 97 to 106%, a limit of detection of 5 mg L-1 and a coefficient of variation (n = 3) of 2.8%. Other applications included determination of ammonium and V in water, Cu in ores and creatine in urine.
Water Urine Geological Detection limit

"Flow Injection Radio-release Analysis For Vanadium"
Anal. Chim. Acta 1991 Volume 246, Issue 2 Pages 329-331
Kate Grudpan and Duangjai Nacapricha

Abstract: The system consisted of a peristaltic pump that delivered the carrier solution (1.2 mL min-1) to a micro-column packed with 110 mAg powder; the packed column was shielded with lead. Acetate buffer solution (pH 3) was used as carrier solution Standard V solution (0.5 to 0.7 ml) was injected into the carrier stream and transported into the micro-column; the released radioactive Ag+ was detected by means of a flow-through coil mounted within a well-type NaI(Tl) detector. The detection limit was 10 µg mL-1 of V; calibration graphs were rectilinear up to 100 µg mL-1.
Buffer Column pH

"Flow Injection Analysis Of Trace Elements By Use Of Catalytic Reactions"
Anal. Chim. Acta 1992 Volume 261, Issue 1-2 Pages 167-182
Takuji Kawashima*, Shigenori Nakano

Abstract: This review covers the mechanism of catalytic reactions involving trace elements, together with catalytic flow injection methods for the determination of Fe, Mn, Cu, Co, V, Cr, Mo and Se, as well as halides and other anions. Representative examples are given of organic compounds used in the indicator reactions. Comparison with batch methods shows that flow injection methods are sometimes less sensitive than their manual counterparts, but afford satisfactory accuracy and precision and have certain advantages (94 references). A review with 94 references. Catalytic reactions have importance in trace analyzes for elements, and kinetic-catalytic methods of anal. based on catalytic reactions have progressed recently. The change in a phys. property such as absorbance, fluorescence, chemiluminescence or electrode potential of a system with time is usually monitored in kinetic-catalytic methods, as these methods include time as a measured variable. Flow injection analysis (FIA) is considered to be a suitable technique for catalytic methods of analysis, i.e., the reaction can easily be controlled by fixing the flow rate of solutions and the length of the reaction coil, yielding reproducible mixing. The adaptation of FIA to catalytic methods can lead to many advantages such as higher precision, better detection limits and rapid sample throughput. After a brief review of the catalytic action of elements in redox reactions, the use of the catalytic reactions in FIA methods is discussed through representative examples.
Fluorescence Chemiluminescence Spectrophotometry Electrochemical analysis Review Catalysis Method comparison

"Online Determination Of Vanadium By Adsorptive Stripping Voltammetry"
Anal. Chim. Acta 1995 Volume 312, Issue 1 Pages 15-25
Gillian M. Greenwaya,* and Georg Wolfbauerb

Abstract: A FIA method was developed based on the adsorption of a V-cupferron complex onto a mercury film electrode followed by cathodic stripping. The wall jet detection cell was fitted with a glassy carbon working electrode, a Ag/AgCl (3 M KCl) reference electrode and a stainless steel counter electrode. The Hg film was deposited in situ (details given) The water carrier stream was switch to the ligand stream containing 20 µM-cupferron and 0.05 M KBrO3 in 0.1 mM acetate buffer at pH 4.6 for the determination of V. Analyte solution was injected into the ligand stream and a deposition potential of +200 mV was applied to the working electrode. After 90 s the voltammogram was recorded in the differential pulse mode with a scan rate of 10 mV/s, a pulse amplitude of 50 mV and an end potential of +50 mV. All flow rates were 0.2 ml/min. The calibration graph was linear up to 3.5 µg/l of V with a detection limit of 8 ng/l. The RSD (n = 10) were 3.5%. The method was applied to the determination of V in tap water. To determine V in matrices which contain a high salt concentration, such as seawater, the measurements were carried out by anodic stripping. A deposition potential of 0 V was applied for 100 s and then the potential was scanned to +150 mV. The RSD for the determination of 1.3 µg/l V in seawater was 7% using a standard additions calibration procedure.
Water Sea Electrode Voltammetry Standard additions calibration

"The Determination Of Lead, Nickel And Vanadium In Saudi Arabian Crude Oil By Sequential Injection Analysis/inductively-coupled Plasma Mass Spectrometry"
Talanta 1996 Volume 43, Issue 8 Pages 1313-1319
Hassan M. Al-Swaidana,*

Abstract: Crude oil was mixed with tetralin, Triton X-100, 40% HNO3, 100 ppm in solution and water to give a homogeneous solution. The solution was aspirated into a holding coil in a sequential injection system and a carrier stream (60 µL/s) swept the sample to a coupled ICP-MS instrument (operating conditions tabulated). The method was used to determine Pb, Ni and V with calibration graphs of 0.3-0.81, 3.13-9.4 and 8.8-13.8 µg/g, respectively, and corresponding recoveries of 98.2, 96 and 101.5%. The RSD (n = 3-5) were 4%.
Crude Mass spectrometry Sequential injection Triton X Surfactant

"Simultaneous Flow Injection Determination Of Iron(III) And Vanadium(V) And Of Iron(III) And Chromium(VI) Based On Redox Reactions"
Talanta 1996 Volume 43, Issue 10 Pages 1755-1760
N. Teshimaa, K. Ayukawaa and T. Kawashimaa,*

Abstract: A sample solution of Fe(III)-V(V) or Fe(III)-Cr(VI) was injected into a carrier stream of 5 mM H2SO4 and diphosphate/acetate buffer solution was injected into a reagent stream of 0.1 M acetate buffer solution. The streams passed through delay coils of 0.1 m and 1.5 m, respectively. The streams merged with each other and then with a reagent stream of 50 µM-V(IV)/50 µM-Fe(II). After passing through a reaction coil (0.2 m), the resulting stream merged with a reagent stream of 1 mM 1,10-phenanthroline and passed through a reaction coil (2 m). The absorbance was measured at 510 nm. Calibration graphs were linear for 1-20 µM-Fe(III) and V(V) and the calibration graph for Cr(VI) was slightly curved over the same range. RSD (n = 10) were 0.54, 0.82 and 0.47% for 20 µM-Fe(III), V(V) and Cr(VI), respectively.
Spectrophotometry Redox

"Continuous-flow System For The Determination Of Trace Vanadium In Natural Waters Utilizing Inline Preconcentration/separation Coupled With Catalytic Photometric Detection"
Talanta 1998 Volume 45, Issue 3 Pages 583-589
Takeshi Yamane*, Yoshie Osada and Miho Suzuki

Abstract: A sensitive and rapid method is presented for the determination of vanadium at ng to sub ng/mL levels in natural waters, in which inline pre-concentration/separation is directly coupled with catalytic detection of vanadaium in a flow injection system. Vanadium was adsorbed on a small column packed with Sephadex G-25 gel and desorbed with a small volume of 0.010 M HCl. The catalytic action of vanadium on the oxidation of chromotropic acid by bromate in pH 3.8 buffered media was used in the sensitive determination of V. Effective pre-concentration/separation of trace vanadium can be achieved from Fe(III), Cu(II) and a large excess of NaCl in seawater sample. A linear calibration using a 5 m sample loop was obtained for 0-2.5 ng V/mL. The limit of detection was 0.02 ng/mL and the relative standard deviation was 1.2% for 1.0 ng V/mL (n = 5). This system is rapid and sensitive and can be readily applied to river water and coastal seawater samples.
River Sea Spectrophotometry Catalysis Preconcentration Buffer Interferences Sephadex Column

"Evaluation Of Multi-component Kinetic Analysis Data By A Partial Least Squares Calibration Method"
Analyst 1993 Volume 118, Issue 11 Pages 1355-1360
Josef Havel, Francisco Jiménez, Roberto D. Bautista and Juan José Arias León

Abstract: A method is described in which a calibration set was obtained from samples of known analyte concentration and used to predict the unknown concentrations of components in a test set. The use of the partial least squares (PLS) method for multi-component kinetic analysis was evaluated by random noise-loaded simulated data sets consisting of two or three components reacting with a reagent. It was possible to determine analytes in mixtures without any previous knowledge either of the rate constants, mechanisms of the reactions and/or molar absorptivities of the components. The PLS algorithm was validated by the simultaneous kinetic determination of Co and V using 4-(1'H-1',2',4'-triazolyl-3'-azo)-2-methylresorcinol as reagent and the stopped-flow injection determination of Fe, Co and Zn using 1-(2-pyridylazo)-2-naphthol-4-sulfonic acid. Both procedures employed spectrophotometric monitoring.
Spectrophotometry Multicomponent Kinetic Partial least squares Stopped-flow

"Lucigenin Immobilized On Silicon Oxides As A Solid-phase Chemiluminescent Reagent"
Analyst 1996 Volume 121, Issue 4 Pages 501-503
O. A. Zaporozhets, V. V. Sukhan and N. A. Lipkovska

Abstract: Lucigenin was adsorbed from aqueous solution on to non-functionalized silica gel. The resulting sorbent was used as a solid-phase chemiluminescent reagent for V(IV) and Fe(II) determination by flow injection, as follows. A stream (1.5 ml/min) of 40 mM KOH was pumped through a Teflon tube (3 cm x 8 mm i.d.) packed with the lucigenin-modified silica gel to a chemiluminescence (CL) cell. A stream (0.2 ml/min) of the V(IV) or Fe(II) solution was also pumped to the CL cell and the CL produced was measured with a CL photometer. The calibration graphs were linear for 0.02-20 mM of both V(IV) and Fe(II). The detection limits were 0.7 µg/l V(IV) and 0.8 µg/l Fe(II). The RSD (n value not given) was 10%.
Chemiluminescence Immobilized reagent Silica gel

"Determination Of Trace Metals In Uranium Oxide By Inductively Coupled Plasma Mass Spectrometry Combined With Online Solvent Extraction"
J. Anal. At. Spectrom. 1992 Volume 7, Issue 3 Pages 565-569
S. Vijayalakshmi, R. Krishna Prabhu, T. R. Mahalingam and C. K. Mathews

Abstract: An online solvent extraction technique for the determination of trace elements in uranium by inductively coupled plasma mass spectrometry is described. An aqueous solution containing uranium (2% m/v) in 1 mol L-1 nitric acid and an organic solvent that can effectively ext. uranium, viz., trioctylphosphine oxide in cyclohexane (0.2 mol L-1), are pumped alternately through a poly(tetrafluoroethylene) (PTFE) tube where they mix thoroughly. The organic phase containing the extd. uranium is removed online by allowing the solution to pass through a microporous PTFE tube which, being hydrophobic, selectively allows the organic phase to permeate through its walls. This technique facilitates rapid and sensitive determination of trace elements in uranium with detection levels in the range 1-45 ppb for La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb, Ag, Ba, Cd, Co, Cr, Cu, In, Li, Mn, Ni, Pb, Sr, Ti, V and Y, 0.1 ppm for Al and 0.5 ppm for Fe. flow rate of about 4 mL min-1 was used.
Inorganic compound Mass spectrometry Sample preparation Solvent extraction Teflon membrane

"Online Removal Of Interferences In The Analysis Of Biological Materials By Flow Injection Inductively Coupled Plasma Mass Spectrometry"
J. Anal. At. Spectrom. 1993 Volume 8, Issue 5 Pages 691-696
Les Ebdon, Andrew S. Fisher, Paul J. Worsfold, Helen Crews and Malcolm Baxter

Abstract: Interference trace metals Cd, Cu, Mn, Pb, V and Zn were removed by chelation with 0.1 g of iminodiacetate-based resin (Na+ form; 50-100 mesh) in a micro-column. The metals were eluted into the VG PlasmaQuad PQ2 spectrometer with 3 M HNO3 by a flow injection procedure. Test recoveries were nearly quantitative except for V (90%) and Zn (85%) and the limits of detection were 0.6-9.9 ng/ml, equivalent to 75-1800 pg of element. Results were tabulated for the determination of the cited elements in five reference materials. The method was not suitable for the determination of Cr.
Biological Mass spectrometry Interferences Reference material Iminodiacetate

"Determination Of Arsenic, Chromium, Selenium And Vanadium In Biological Samples By Inductively Coupled Plasma Mass Spectrometry Using Online Elimination Of Interference And Preconcentration By Flow Injection"
J. Anal. At. Spectrom. 1994 Volume 9, Issue 5 Pages 611-614
Les Ebdon, Andrew S. Fisher and Paul J. Worsfold

Abstract: A 0.5 g portion of the biological material was digested with 3 mL of HNO3 and 2 mL of water for 16 h and then irradiated in a microwave oven at 300 W for 3 min. After cooling, 0.1 g of potassium persulfate was added and the digest was microwaved at 300 W for a further 2 min; H2O2 (1 ml) was then added and the digest was irradiated with a 150 W Xe lamp for 18 h to decompose arsenobentaine. The digest was diluted to 50 mL with Tris buffer (pH 9) following the addition of 3 mL of 60% NaOH. A 200 µL portion of this solution was injected into the water carrier stream (1.5 ml/min) of the flow manifold and passed through the alumina column (2.5 cm x 3 mm i.d.). The analytes were subsequently eluted from the column by injecting 200 µL of 1 M HNO3 into the carrier stream and determined by ICP-MS. The detection limits for V, Cr and As were 0.12, 0.6 and 0.9 µg/g. To achieve a detection limit of 1 µg/g for Se it was necessary to use an alternative procedure which involved the pre-concentration of 10 mL of digest. The recoveries of 60 ng/ml of Cr, Se and V and 600 ng/ml of As from a spiked biological reference material (Tort-1, lobster hepatopancreas) were 98-109%, respectively.
Biological material Mass spectrometry Reference material Preconcentration Interferences

"Direct Determination Of Trace-metals In Seawater Using Electrothermal Vaporization Inductively-coupled Plasma-mass Spectrometry"
J. Anal. At. Spectrom. 1996 Volume 11, Issue 8 Pages 549-553
Graeme Chapple and John P. Byrne

Abstract: A method is described for the direct analysis of five transition elements (Go, Cu, Mn, Ni, V) in sea-mater using ETV-ICP-MS, Interferences from the seawater matrix were eliminated by a combination of in situ separation of analyte and matrix components in the ETV, and use of nitric acid as a chemical modifier, The nitric acid facilitates the removal of chloride from the seawater matrix during the sample drying stage, whilst optimization of the ETV heating program allows for effective separation of residual matrix and analyte species, thus reducing ionization suppression and space charge effects in the ICP-MS, Calibration standards, prepared by spiking a seawater matrix stripped of trace metals by ion exchange, gave excellent linearity and allowed for direct determination of selected analytes without the use of standard additions, Detection limits ranged from 0.003 µg L-1 for V to 0.14 µg L-1 for Cu. The precision and accuracy of the method mere checked by analysis of two certified reference sea-waters.
Sea Mass spectrometry Reference material 8-Hydroxyquinoline Interferences Optimization

"Comparative Analysis Of Aluminum Oxide Powders By Inductively Coupled Plasma-mass Spectrometry With Low And High Mass Resolution"
J. Anal. At. Spectrom. 1996 Volume 11, Issue 9 Pages 797-803
Norbert Jakubowski, Wolfgang Tittes, Dagmar Pollmann, Dietmar Stuewer and José A. C. Broekaert

Abstract: ICP-MS with low and moderate mass resolution was applied to the determination of trace elements (B, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Zr, Ba, La and Ce) in two different pare Al2O3 powders after decomposition. Four different sets of measurements were performed: (1) with quadrupole instrument in standard operation; (2) with the same instrument including an online matrix trace separation step; (3) with a double-focusing magnetic field instrument operated at;low resolution (R=300); and (4) with the same instrument operated with moderate resolution (R=3000). Generally, the quantitative results obtained with the four different techniques are in good agreement. Application of the double-focusing instrument with moderate mass resolution permitted the determination of spectrally interfering elements such as V, Cr, Mn, Fe and Ga in Al2O3 in the 0.04-10 µg g-1 range far above the detection limit. For all four applied techniques, blank values arising from the reagents and instrumentation were a major limitation for a number of elements, and the lowest detection limits were obtained in each instance for elements that do not suffer from limitations due to blank values.
Water Environmental Inorganic compound Mass spectrometry Interferences Method comparison

"Ultratrace Analysis Of Antarctic Snow And Ice Samples Using High Resolution Inductively Coupled Plasma Mass Spectrometry"
J. Anal. At. Spectrom. 1998 Volume 13, Issue 5 Pages 463-468
Ashley T. Townsend and Ross Edwards

Abstract: High resolution ICP-MS was used to determine the concentrations of Al, Sc, V, Mn, Fe, Co, Pb and Bi in snow and ice from Antarctica. To overcome some potentially problematic spectral interferences, measurements were acquired in both low and medium resolution modes. Small sample volumes were analyzed using a microconcentric nebulizer. After rigorous instrument cleaning and sample preparation, detection levels in the low and sub-pg g-1 range (0.3-48 pg g-1) were found for all elements. Concentration. values were determined for a continental snow, sea ice snow and a representative ice core. Concentration. ranges for all snow samples (n = 25) were (in pg g-1): Al (30-2000), V (2-16), Mn (2-30) and Fe (30-1500), while Sc and Co were typically below detection or blank limits. The ice core sample had Al, Mn, Fe and Pb concentrations of 90, 7, 110 and 1 pg g-1, respectively, while Sc, V, Co and Bi could not be quantified (below detection or blank limits). The reliability of the analytical method for Fe was confirmed by flow injection analysis with spectrophotometric detection.
Ice Snow Mass spectrometry Interferences Method comparison

"New Configuration For Construction Of PH Gradients In Flow Injection Analysis"
Anal. Chem. 1986 Volume 58, Issue 3 Pages 663-664
Angel Rios, M. Dolores Luque de Castro, and Miguel Valcarcel

Abstract: The configuration incorporates a second injection valve containing 4-(2-pyridylazo)resorcinol in the loop of the sample valve. The simultaneous injection of the two valves provides a reacting plug with three zones ensuring adequate resolution of the reagent mixtures. The system is applied to the spectrophotometric determination of Pb and V by flow injection by using a Pye Unicam SP6-500 instrument and a Hellma 178.12 QS flow cell. The new configuration ensures the establishment of the correct pH gradients and reagent concentration. at the centre of the injected sample.
Water Spectrophotometry Gradient technique pH gradient Tecator

"Determination Of Chromium(III), Titanium, Vanadium, Iron(III), And Aluminum By Inductively Coupled Plasma Atomic Emission Spectrometry With An Online Preconcentrating Ion Exchange Column"
Anal. Chem. 1986 Volume 58, Issue 13 Pages 2602-2606
Shizuko Hirata, Yoshimi Umezaki, and Masahiko Ikeda

Abstract: A method utilizing a miniature ion-exchange column of Muromac A-1 (Muromac Chemicals, Tokyo) has been developed to increase the sensitivity for aluminum, chromium(III), iron(III), titanium, and vanadium measurements by inductively coupled plasma atomic emission spectrometry (ICPAES). A sample (pH 3.8) is pumped through the column at 6.0 mL min-1, mixing with the buffer solution, and sequentially eluted directly to the nebulizer of the ICP with 2 M HCl acid at 3.0 mL min-1 by using a flow injection analysis (FIA) system. This FIA-ICP method gave signal enhancements that were 34-113 times better than for a conventional continuously aspirated system for the metals studied here. A precision of the technique is better than 5 YO relative standard deviation at the 10 µg L-1 level for aqueous standards, and the sampling rate is 17 samples h-1.
Ion exchange Spectrophotometry Column Preconcentration

"Measurement Of Vanadium, Nickel, And Arsenic In Seawater And Urine Reference Materials By Inductively Coupled Plasma Mass Spectrometry With Cryogenic Desolvation"
Anal. Chem. 1993 Volume 65, Issue 18 Pages 2468-2471
Luis C. Alves, Lloyd A. Allen, and R. S. Houk

Abstract: Addition of a small dose (2%) of H2 to the aerosol gas flow enhanced analyte signals by a factor of 2-3, which compensated for the loss of analyte signal that accompanied earlier efforts at cryogenic desolvation with inductively coupled plasma mass spectrometry (ICP-MS). Vanadium, nickel, and arsenic at microgram per liter levels in urine, river, and seawater reference materials were determined. The polyatomic ions ClO+, CaO+, and ArCl+, which normally cause severe overlap interferences for these elements, were attenuated to manageable levels by cryogenic desolvation. The samples were simply diluted with 1% HNO3 so that the chloride could be removed as HCl. The analytical results obtained for these standard reference materials agreed closely with the certified or recommended values. The detection limit ranges (3s) obtained were 10^-1000 ng L-1 for V, 0.03-20 µg L-1 for Ni, and 4-7000 ng L-1 for As in the original samples. The samples were introduced by flow injection to minimize clogging of the sampling orifice.
Sea Urine River Mass spectrometry Reference material Interface Interferences

"Online Standard Addition Method With ICP-MS Using Flow Injection"
Anal. Chem. 1995 Volume 67, Issue 9 Pages 1553-1557
Diane Beauchemin

Abstract: A Perkin-Elmer SCIEX ELAN 500 instrument fitted with a mass flow controller, a PlasmaTherm torch and a translational stage for the torch box was used in conjunction with a single-line flow injection manifold in which a peristaltic pump controlled the flow of carrier to a sample injection valve connected to the Meinhard nebulizer by PTFE tubing. Operating conditions used to determine trace metals in 1% HNO3/0.01 M K medium and in standard seawater are tabulated. Initially, 1% HNO3 was used as carrier, into which a multi-element or single-element standard was injected. After rinsing of the loop, the sample was injected. The standard was then used as carrier for a further injection of sample. To minimize rinsing time, for the next run the sample was injected first into the standard carrier and then into the blank carrier, after which the standard was injected into the blank carrier. Sample consumption was reduced, a matrix-matched blank was not necessary, and sensitivity was close to that with continuous sample nebulization. However, precision was poorer than that of peak height calibration. The method was used to determine Mo in standard seawater. A single-line flow injection manifold was used to perform the standard addition method online with ICPMS. The proposed approach requires injection of the sample into two different carriers (i.e., a blank and a standard with a greater concentration than that of the sample), as well as injection of the standard in the blank carrier. The method takes into account the change in sensitivity induced by the sample upon its injection into the standard carrier. In the best conditions, one replicate multielemental analysis by the online standard addition method was accomplished in 200 s (using 100 mL injections). Furthermore, the setup induced only limited dispersion (i.e., the dispersion coefficient was between 1.2 and 2) and therefore provided sensitivity similar to that expected from direct continuous nebulization of the sample. Although precision was poorer than that which is typical of, for instance, external calibration, the proposed method adequately compensated for the effect of a 0.01 M K matrix, allowing the accurate determination of V, Co, Ni, Cu, Zn, Mo, Cd, Sb, and Pb in this matrix. The method was also successfully applied to the direct determination of Mo in seawater. Copyright 1995, American Chemical Society.
Sea Mass spectrometry Reference material Standard additions calibration

"Study And Application Of A Method For The Determination Of Metallic Elements By ICP-AES With Preconcentration On An Active Carbon-silica Gel Microcolumn In A FI System"
Fresenius J. Anal. Chem. 1998 Volume 360, Issue 6 Pages 721-723
Hongnian Ji, Zhenhuan Liao, Junmei Sun, Zucheng Jiang, Hongnian Ji, Zhenhuan Liao, Junmei Sun, Zucheng Jiang

Abstract: Using active carbon-silica gel as adsorbent and sodium diethyldithiocarbamate (NaDDTC) as chelating reagent in a flow injection system, an ICP-AES method was developed for pre-concentration and determination of trace metallic elements in high purity rare earth oxides. The experimental parameters such as pH, flow rate, amt. of adsorbent, length of reaction coil and eluent acidity were optimized. At pH 4.6 Al, Cr, Cu, Fe, Pb, V, Zn could be pre-concentrated, and subsequently determined by ICP-AES. This method can eliminate matrix effects. Its enrichment factors were 8.1-12.6 with detection limits in the ng/mL range and RSD of 2.3-5.0. This method was applied to the analysis of high purity of La2O3, and Eu2O3 with satisfactory results.
High purity High purity Spectrophotometry Activated carbon Silica gel Preconcentration Chelation Diethyldithiocarbamate Optimization

"Application Of An Online Preconcentration System In Simultaneous ICP-AES"
Microchim. Acta 1992 Volume 106, Issue 3-6 Pages 191-201
Peter Schramel, Li -Qiang Xu, Günter Knapp and Markus Michaelis

Abstract: A PC-controlled online pre-concentration system (TRACECON) was connected to a JY-70 Plus simultaneous inductively coupled plasma (ICP) spectrometer to pre-concentrate online seven trace elements (Cu, Fe, Zn, Cr, Ni, Mn, V) in biological and environmental samples. EDTrA-cellulose was used as column material. The elemental concentrations were determined by simultaneous ICP-AES. The effect of pH of the sample solution on the enrichment was studied. It was found that the recoveries of chromium and iron depend strongly on the pH of the sample solution. All the elements mentioned were recovered quantitatively at pH 4.0. The flow rates of sample solution and element solution were optimized. The enrichment factors for seven elements at 5 mL loading volume range from 3.9 for Cu to 7.9 for Zn. The detection limits of all seven elements were improved. The accuracy of the method was tested by the analysis of a number of CRMs of NIST, BCR and NIES. Most results are in good agreement with the certified values.
Biological Environmental Spectrophotometry Computer Reference material Preconcentration Column Optimization pH

"Flow Injection Spectrophotometric Determination Of Molybdenum And Vanadium With Carminic Acid In The Presence Of Cetyltrimethylammonium Bromide"
Microchim. Acta 1995 Volume 118, Issue 3-4 Pages 203-211
Tomás Pérez-Ruiz, Carmen Martínez-Lozano, Virginia Tomás and Conceptión Paredes

Abstract: Portions (85 µL) of 4 mM carminic acid solution of ~ pH 4 were injected into streams (1.2 ml/min) of Mo or V [V was pre-reduced to V(IV) with 1% ascorbic acid] solutions. The resulting stream was merged with a stream (1.2 ml/min) of 4 mM cetyltrimethylammonium bromide, and then with a stream (1.2 ml/min) of 0.5 M acetate buffer of pH 4.6. After passing through a reaction coil (100 cm x 0.5 mm i.d.) where the flow was stopped for 60 s, the solution passed to a 18 µL flow cell for measurement of absorbance at 585 and 575 nm for Mo and V, respectively. The calibration graphs were linear for 0.76-28.8 and 0.3-9.1 µg/ml Mo and V, respectively, and the corresponding detection limits were 0.33 and 0.16 µg/ml; the corresponding RSD were 0.68-0.82% and 1.1-1.4% (n = 10). Sample throughput was 33/h. Tolerance levels of interfering ions are tabulated. The method was applied to steel, pharmaceuticals (multivitamins) and petroleum products (sample preparations described).
Product Pharmaceutical Alloy Spectrophotometry Sample preparation Stopped-flow Interferences

"The Use Of Reference Materials In The Fossil Fuels Quality Control"
Microchim. Acta 1996 Volume 123, Issue 1-4 Pages 217-230
Maurizio Bettinelli, Sandro Spezia, Umberto Baroni and Gabriele Bizzarri

Abstract: Quality control procedures used for the determination of trace elements in fuel oil and coal are described. Two standard reference materials (NIST 1632a and 1632b) were used to evaluate the accuracy in the determination of As, Hg and Se in coal by flow injection (FI) hydride-generation (HG) AAS and FI HG ICP-MS after microwave solubilization (Anal. Chim. Acta, 1989, 225, 159). RSD over 2 years were 10% for As, 8.11% for Se and 15% for Hg. The use of real fuel oil samples to compare results obtained for the determination of Ni and V by NAA, ICP-MS, ETAAS and ICP-AES in 54 laboratories is discussed. Similarly, the use of real samples to detect significant bias in the determination of As, Hg and Se in coal using various techniques (NAA, FI HG AAS, FI HG ICP-MS, ETAAS) is discussed.
NIST 1632 Oil Sample preparation Spectrophotometry Spectrophotometry Mass spectrometry Mass spectrometry Reference material Method comparison

"Determination Of Vanadium By Its Catalytic Effect On The Oxidation Of Gallocyanine With Spectrophotometric Flow Injection Analysis"
Microchem. J. 1996 Volume 53, Issue 2 Pages 139-146
Ali A. Ensafi and A. Kazemzadeh

Abstract: Portions (200 µL) of standard V solutions were injected into a carrier stream of water at 0.5 ml/min delivered by a 12-channel peristaltic pump in a flow injection system (schematic shown). The sample-containing carrier stream was mixed sequentially with streams of 3.5 µM-gallocyanine (I) in a citrate buffer of pH 4 and 0.9 M NaBrO4 solution (both at 0.5 ml/min) in a 250 cm reaction coil. The decrease in the absorbance of I resulting from its V-catalyzed oxidation by bromate was measured at 620 nm. The calibration graph was linear from 0.01-100 ng/ml of V(V) [0.002-20 ng/200 µL solution] and the detection limit was 0.001 ng/200 µL. RSD (n = 10) were 3.2, 2, 1.7 and 1.1%, respectively, for 0.01, 0.1, 5 and 20 ng V(V). Tolerance levels for forty foreign ions and cations are listed. A throughput of 40 samples/h was achieved. The method was applied to the analysis of V(V) in human serum, crude petroleum and river water with recoveries of 100-105%.
Crude Product Serum Human River Environmental Spectrophotometry

"Online Multielement Preconcentration And Inductively Coupled Plasma Atomic Emission Spectrometric Determination Of Transition Metals Using A Flow Injection Hydraulic High-pressure Nebulization-desolvation Sample Introduction System"
Microchem. J. 1998 Volume 58, Issue 3 Pages 245-250
Attila Gáspár, József Posta, Mihály Braun and Csilla Sógor

Abstract: A method was developed for simultaneous pre-concentration and online determination of 15 transition metals (Ag, Au, Cd, Cr, Cu, Fe, In, Ni, Pb, Pd, Pt, Ti, Tl, V, Zn). A polyether-ether-ketone (PEEK) loop as pre-concentration unit introduced by the authors earlier was used for the multielement flow injection (FI) pre-concentration of transition metal-pyrrolidinedithiocarbamate complexes. The pre-concentrated complexes were eluted with iso-Bu Me ketone and introduced into the inductively coupled plasma with a hydraulic high-pressure nebulizer (HHPN) and desolvation unit. The desolvation system, the use of which was necessary for aerosol of iso-Bu Me ketone eluant, was optimized. The enrichment factors of the 15 transition metals were 14-67 due to 2 min of pre-concentration time.
Spectrophotometry Preconcentration Polyetheretherketone Complexation MIBK Optimization Interface

"Determination Of Trace Elements In Power Plant Emissions By Inductively Coupled Plasma Mass Spectrometry: Comparison With Other Spectrometric Techniques"
Microchem. J. 1998 Volume 59, Issue 2 Pages 203-218
M. Bettinelli, S. Spezia, U. Baroni and G. Bizzarri

Abstract: Particulate matter in stack effluents of coal-fired plants was collected with an isokinetic probe nozzle suitable for (a) total particulate samplings on membrane filters and (b) sampling with a low volume 10-stage single orifice cascade impactor plus a backup filter. A microwave digestion method using an acid mixture of HNO3-HCl-HF in a closed vessel was developed for the determination of major, minor, and trace elements in very small amounts of sample. Analyses were carried out by inductively coupled plasma mass spectrometry (ICP-MS). A recovery study was conducted using multielemental standard solutions, NIST1633a Trace Elements in Coal Fly Ash and NIST 1648 Urban Particulate Matter, to examine the capabilities of the method. The results for real samples dissolved by this procedure were compared with results obtained by instrumental neutron activation anal., graphite furnace atomic absorption spectrometry, and flow injection hydride generation atomic absorption spectrometry. The anal. capabilities of ICP-MS make it one of the techniques of choice for the determination of trace elements in emission particulate matter collected in different granulometric particle sizes.
Industrial NIST 1633 NIST 1648 Mass spectrometry Sample preparation Method comparison Reference material

"Simultaneous Measurements Of Trace Metals By Adsorptive Stripping Voltammetry"
Electroanalysis 1989 Volume 1, Issue 3 Pages 229-234
Joseph Wang*, Jawad Mahmoud, Javad Zadeii

Abstract: Simultaneous measurements of trace metals, based on adsorptive stripping voltammetry of their chelates with dihydroxyazo dyes, are demonstrated. Variables affecting the resolution between neighboring chelate peaks, including the ligand and its concentration, pH, adsorption time and potential, concentration ratio, and scan rate, are assessed. Adequate resolution is demonstrated for more than 10 pairs of metals, present at the ppb level. Possible changes in peak heights, associated with competition for the complexing ligand and/or coadsorption effects, are explored. Different concentration ratios of the mixture components can be tolerated. Applicability to seawater analysis is illustrated.
Water Voltammetry

"Flow Injection Thermospray Sample Deposition For Electrothermal-atomization Atomic Absorption Spectrometry"
Spectrochim. Acta B 1988 Volume 43, Issue 8 Pages 983-987
P. C. Bank, M. T. C. De Loos-Vollebregt and L. De Galan

Abstract: Details (with diagram) are given of a system for flow injection of a sample (10 µL) into a thermospray vaporizer for introduction into a pre-heated pyrolytically coated graphite tube furnace. AAS is carried out with deuterium background correction. The characteristic mass for V with peak height measurement is 23 pg, compared with 34 pg by auto-sampling Zeeman AAS; reproducibilities of introduction in the two systems are similar. Sensitivity falls with increasing furnace temperature (>150°C) during deposition, but this problem can be ameliorated by injecting a larger volume, and furnace cycle time is reduced (to, e.g., ~20 s).
Ion exchange Spectrophotometry Interface Optimization

"Flow Injection Thermospray Sample Deposition For Electrothermal-atomization Atomic Absorption Spectrometry"
Spectrochim. Acta B 1989 Volume 44, Issue 6 Pages 571-579
P. C. Bank, M. T. C. de Loos-Vollebregt and L. de Galan

Abstract: The flow injection thermospray introduction system described previously (Ibid., 1988, 43B, 983) has been modified to obtain more reproducible sample deposition on to the wall of a graphite-tube atomizer. Under optimum conditions, viz, a sample flow rate of 0.7 mL min-1, a thermospray vaporizer temperature of 300°C and a deposition temperature of 120°C in the graphite tube, the sensitivities for Ag, Al, As, Au, Cd, Co, Mn, Pb, Ru and V were identical with those obtained by conventional graphite-furnace AAS. The area of spray-deposited material formed on the wall of the graphite tube is independent of sample volume (unlike conventional manual injection), and thus the flow injection thermospray system can be used over wide analytical ranges. Solutions containing up to 2% of NaCl could be injected without plugging of the thermospray vaporizer capillary.
Spectrophotometry Optimization Interface

"Catalytic Spectrophotometric Determination Of Picogram Amounts Of Vanadium In Natural Fresh And Tap Water By Flow Injection Analysis"
Anal. Sci. 1996 Volume 12, Issue 2 Pages 237-242
S. KAWAKUBO, K. KAJIHARA and M. IWATSUK

Abstract: A spectrophotometric FIA method for the analysis of V down to 0.001 µg/l, based on its catalytic effect on the oxidation of o-phenylenediamine (OPDA) with bromate at pH 4 and 50°C in the presence of gallic acid as an activator, is presented. Portions (200 µL) of standard V solutions were injected directly into a carrier stream of water (0.8 ml/min) of a flow injection manifold (schematic shown) previously described by Kawakubo et al. Analyst [Cambridge, UK], 1995, 120, 2719). The carrier stream was merged sequentially with three reagent streams (0.2 ml/min), 14 mM gallic acid solution containing 1.5 M acetic acid and 0.35 M sodium acetate buffer of pH 4, 0.07 M OPDA and 0.7 M bromate solution in a reaction coil (4 m x 0.5 mm i.d.) in a temperature-controlled water bath and the oxidized OPDA produced was detected at 450 nm. The calibration graph was linear up to 8 µg/l for both V(IV) and V(V) and the detection limit and sampling frequency were 4 ng/l (0.8 pg) and 30 samples/h, respectively. The detection limit was 10-times lower than that obtained by the previous fluorimetric method (loc. cit.). Tolerance levels for five foreign ions (listed) and humic acid are given. The method was successfully applied to the analysis of lake, river, ground, rain and tap water samples with recoveries of 100-105%.
Water Ground Lake Rain River Spectrophotometry

"Determination Of Major And Trace-elements For Certified Reference Material Of Riverine Water JAC-0031 And JAC-0032 By ICP-MS"
Anal. Sci. 1997 Volume 13, Issue 2 Pages 177-182
T. SHIMAMURA and M. IWASHITA

Abstract: Element concentrations were determined by ICP-MS for certified reference materials of riverine water JAC 0031 and JAC 0032 which were recently distributed for a collaborative study to determine certified values. Concentrations were determined of nine elements (Mg, Al, Mn, Ni, Cu, Zn, As, Cd and Pb) out of sixteen elements, which were intended to be certified. An additional eleven trace elements (Li, V, Co, Rb, Sr, Mo, Sb, Cs, Pa, W and U) were also determined. The results obtained for the former nine elements generally agreed well with the values from other laboratories and with certified values. The results obtained for the latter eleven elements were consistent with our previous data, which were obtained from our monitoring project for the same river at a nearby sampling point. 39 References
JAC 31 JAC 32 River Mass spectrometry Reference material Method comparison

"Flow Injection Analysis Automation With Fluorimetric Detection And Its Application To Vanadium Determination In Petroleum Derivatives"
Analusis 1990 Volume 18, Issue 8 Pages 491-496
Forteza, R.;Oms, M.T.;Cardenas, J.;Cerda, V.

Abstract: A fully automatic fluorimetric FIA system was used to monitor the catalytic auto-oxidation of Na 4,8-diamino-1,5-dihydroxyanthraquinone 2,6-disulfonate (I) by VV with excitation at 524 nm and emission at 582 nm. The FIA system contained an injection module, a manifold constructed from PTFE tubing (i.d. 0.5 mm), a Perkin-Elmer LS5 fluorimeter and an IBM PC. The sample stream was reacted with a stream of 6N-HCl containing 50 µL of injected 0.1 mM I (0.80 mL min-1 each) in a 4-m straight reactor at 30°C. Calibration graphs were rectilinear for 0.2 to 0.8 and 0.8 to 2 mg L-1 of VV. For 0.4 mg L-1 of VV, the coefficient of variation was 1% (n = 17). The tolerance limits of eighteen ions in the determination of 0.5 mg L-1 of VV are tabulated, the most serious interference being observed for Fe3+, Ce4+ and Al3+. The method was applied to Boscan crude and heavy gas oil samples (procedures described).
Crude Gas Fluorescence Automation Calibration Interferences Catalysis

"Simultaneous Determination Of A Binary Mixture: Kinetic Method For Determination Of Uranium And Vanadium"
Analusis 1993 Volume 21, Issue 10 Pages 421-424
Jianhua, W.; Ronghuan, H.

Abstract: The flow injection method was based on the kinetic differences of the catalytic effects of U(IV) and V(IV) on the oxidation of I- by Cr(VI). All solution were adjusted to pH 2 with HCl. Sample solution in 0.1% starch (20 µL) were injected into the carrier solution of 0.1% starch (3.2 ml/min), which was mixed in a PTFE coil (30 cm x 0.5 mm i.d.) with 18 mM KI solution (3 ml/min). This solution was further mixed with 1.6 mM Cr(VI) solution (3 ml/min) in a second coil (15 cm x 0.5 mm i.d.) and transferred to the stop-flow cell. Absorbances were measured at 590 nm at 15 s and 30 s after stopping the flow. Equations are given for calculating the U(IV) and V(IV) concentrations. Calibration graphs were linear for 0~3.6 µg/ml of U(IV) and 0~2.5 µg/ml of V(IV), with detection limits of 0.024 and 0.01 µg/ml, respectively. Of 20 cations tested, only Fe(II) and Sb(III) interfered seriously, with an error of 5% at 1 µg each of the analytes and 1 µg of the interferents. The method was tested on synthetic samples and a phosphate ore; the results were comparable with those obtained by AAS. RSD were 1.7-4.8%.
Phosphate Kinetic Interferences Stopped-flow

"Catalytic Determination Of Vanadium By Micro Ion Exchange Separation-flow Injection Method And Its Application To Rain Water"
Bunseki Kagaku 1984 Volume 33, Issue 11 Pages 609-614
Fukasawa, T.;Kawakuba, S.;Okabe, T.;Mizuike, A.

Abstract: Sample solution (2.5 ml) in 20 mM HCl - 0.1% H2O2 is passed through a column (4.5 cm x 1.7 mm) of Amberlite CG-400. The column is washed with 0.5 mL of the same solvent mixture, followed by 1 mL of 20 mM HCl. Vanadium is eluted with 0.2 mL of 2 M HCl, the pH is adjusted to 8 to 9 with aqueous NH3 and the solution is diluted to 0.25 mL with water. An aliquot (0.1 ml) is injected into a stream of 0.25 M NaBrO3 - 30 mM gallic acid (pH 3.8) for the catalytic spectrophotometric determination of V at 380 nm. From 0.1 to 5 ng of V can be determined within 40 min. Tolerance levels of Al, Fe(III), Mo(VI) and W(VI) are 5, 100, 25 and 50 µg, respectively. The method was applied in the determination of V in rain.
Rain Ion exchange Spectrophotometry Amberlite Catalysis Interferences Resin

"Analysis Of River Water By ICP-MS With Online Preconcentration Using Flow Injection"
Can. J. Anal. Sci. Spectrosc. 1998 Volume 43, Issue 2 Pages 43-48
Beauchemin, D.;Specht, A.A.

Abstract: A flow injection manifold is described for online pre-concentration. of several elements and their determination by inductively coupled plasma mass spectrometry. This manifold incorporates a cleaning column on the buffer line to remove trace contaminants from the buffer prior to its mixing with the sample. A 2 M HNO3 eluent is used to determine elements which suffer from spectroscopic interferences from Cl-containing compounds The pre-concentration. factor can easily be changed by simply modifying the sample loading time (i.e., the amt. of time the sample is pumped through the anal. column). A 30-fold pre-concentration. (using 1.5 mL sample and 50 µL eluent) was used to analyze certified river water, SLRS-2. Under these conditions, sample throughput was ~20 samples/h. Results agreed well with certified values for V, Co, Cd, and Pb using standard additions, and for V, Co, Cd, and Sb using external calibration. Both calibration strategies provided results of similar accuracy and precision, but the latter was far less time-consuming. Trace determination of ubiquitous elements such as Zn is still precluded by a high blank.
River NRCC SLRS-2 Mass spectrometry Reference material Preconcentration Interferences

"Kinetic Spectrophotometric Method For Simultaneous Determination Of Uranium, Iron And Vanadium With A Stopped-flow Technique"
Chem. Anal. 1993 Volume 38, Issue 4 Pages 497-504
Jianhua, W.;Ronghuan, H.

Abstract: Sample solution was injected into a carrier stream of aqueous 0.1% starch solution of pH 2 (3.2 ml/min) and the stream was merged with a stream (3 ml/min) of 18 mM KI before passing through a reaction coil (30 cm x 0.5 mm). The resulting stream was merged with a stream of 1.6 mM potassium dichromate of pH 2 and after passing through a second coil (15 cm x 0.5 mm) the stream was driven into the flow cell and stopped. The presence of the analytes induced a reaction between Cr(VI) and iodide, which was indicated by the formation of the colored I3-starch complex. The absorbance of this complex was monitored at 590 nm at 10, 20 and 30 s from the stop of the flow. The calibration graphs were rectilinear up to 3.6, 2.8 and 2.5 µg/ml for U, Fe and V, respectively, with corresponding recoveries of 95.1%, 104.8% and 96.7% and detection limits of 0.024, 0.08 and 0.01 µg/ml. Only Sb(III) and Ti(III) interfered. The method was applied to the simultaneous determination of U, Fe and V in phosphate ore and a synthetic sample (details given), with RSD from 3.9-5.1% and 3.6-5.6%, respectively.
Phosphate Spectrophotometry Kinetic Stopped-flow Interferences

"Simultaneous Spectrophotometric Determination Of Lead, Vanadium And Copper By PH Gradients Technique In Flow Injection Analysis And Kalman Filter"
Fenxi Huaxue 1993 Volume 21, Issue 1 Pages 63-65
Zhang, G.Y.;Huang, Q.S.;Mao, D.S.;Chen, T.Y.

Abstract: The principle of the cited method is described. Lead, V and Cu in mixed solution are determined spectrophotometrically by injection of a portion of the sample solution (pH 2) and 0.013% 4-(2-pyridylazo)resorcinol (I) solution (pH 2) into a carrier stream (pH 10) containing 0.0013% I, 1% NH4Cl and aqueous 0.5% NH3, followed by detection at 530 nm. The absorbance data of the formed complex within the pH gradients were collected with a microcomputer and processed by Kalman filter algorithm. Recoveries of Pb, V and Cu were 98.5, 101 and 99.8%, respectively; corresponding coefficient of variation were 3.5, 2.8 and 3.4%.
Spectrophotometry Multidetection Gradient technique Kalman filter pH gradient

"Stopped-flow Flow Injection Method For The Simultaneous Determination Of Elements - Simultaneous Determination Of Iron, Titanium And Vanadium"
Fenxi Huaxue 1993 Volume 21, Issue 11 Pages 1289-1292
Wang, J.H.;He, R.H.

Abstract: The method described previously (Wang et al., Ibid., 1993, 21, 593) was used to determine Fe, Ti and V in Al alloy and synthetic samples. The method was based on the formation of I3- by the Cr(VI)-I- reaction, which was catalyse by the analytes. Aluminum alloy (0.2 g) was dissolved in 10 mL of 30% H2O2 and 6 mL of 6 M HCl, the solution was boiled for 30 min and treated with Zn powder. The solution was adjusted to pH 2.1 and diluted to 200 mL with water. The solution was injected into a carrier solution of 0.1% starch solution at 3.8 ml/min, treated with 122 mM KI at 2.8 ml/min and 1.5 mM Cr(VI) at 2.8 ml/min at 25°C in two PTFE reaction coils (30 cm and 15 cm) before detection at 590 nm. The average sampling rate was 90 h-1. Calibration graphs were linear for up to 2.2, 3.1 and 1.8 µg/ml of Fe(II), Ti(III) and V(IV), respectively. Recoveries were 93.7-107.9% for Fe, 93.2-108.4% for Ti and 92.6-106.3% for V; their corresponding detection limits were 0.012, 0.02 and 0.08 µg/ml. Tolerance levels are for several ions; Sb(III) interfered seriously.
Alloy Spectrophotometry Stopped-flow Multidetection Interferences

"A Stopped-flow Injection Catalytic-spectrophotometric Method For The Determination Of Trace Vanadium"
Fenxi Huaxue 1996 Volume 24, Issue 7 Pages 832-834
Wang, S.H.;Zhang, A.M.;Du, L.Y.;Ma, C.L.;Liu, D.J.

Abstract: An aqueous 0.0025% malachite green solution in 0.01 M acetic acid was injected into a carrier stream of 0.01 M acetic acid (3 ml/min) and mixed in a reaction coil (25 cm long). The mixed reagent stream was merged with a sample stream containing 1 mM KBrO3 and 0.05 M tartaric acid flowing at the same rate in a second reactor (35 cm long) and the absorbance of the colored products formed was measured at 625 nm. When the absorption reached the maximum, the flow was stopped; the curve of the absorbance change was plotted for calculation of the V content. The calibration graph was linear from 20-200 µg/l of V(V). Common foreign species including 100-fold Fe(III), Co(II), nitrite and Mn(II) did not interfere. The method was applied to the analysis of foods, such as peanut, rice and wheat flour, with RSD of 2.6-3.3%. Results agreed closely with those published Wang et al. (Fenxi Shiyanshi, 1995, 14, 70).
Rice Flour Food Spectrophotometry Interferences Stopped-flow

"Flow Injection Catalytic Spectrophotometric Determination Of Trace Amounts Of Vanadium In Geochemical Exploratory Samples"
Fenxi Huaxue 1996 Volume 24, Issue 7 Pages 838-840
Liu, G.J.;Li, J.X.;Zhao, X.M.

Abstract: Sample (2-50 mg) was digested with 2 mL H2SO4 (1:1), 2 mL concentrated HCl and 5 mL HF and the digest was applied to a strongly-basic anion-exchange resin column. Portions (200 µL) of eluate were injected, via a sampling coil, into a carrier stream of 9% ascorbic acid at 0.75 ml/min and mixed with a reagent stream containing 0.005% beryllon III and ammonium acetate/ammonia water buffer of pH 7.5 at 0.75 ml/min in a reaction coil (830 cm x 0.5 mm i.d.) at 90°C. The colored products formed were detected spectrophotometrically at 480 nm. The amount of V was calculated after evaluation of the absorbance difference with that of a reagent blank. The calibration graph was linear up to 80 µg/l of V with detection limit of 7 µg/l. The RSD (n = 30) was 0.6% for 0.4 mg/l of V. Analysis time was reduced from 1 h by the conventional technique to ~e;1 min by this method. Interference from co-existing foreign ions, viz. Cu(II), Fe(III), Mo(V), Ni(II), Ce(IV), As(V) and Pb(II) were removed during the ion-exchange treatment. Sampling frequency was 60 runs per h.
Geological Spectrophotometry Interferences

"Determination Of Trace Non-rare-earth Metals In High-purity Lanthanum Oxide By ICP-AES With Preconcentration On An Active Carbon-silica Gel Microcolumn In A Flow Injection System"
Fenxi Kexue Xuebao 1996 Volume 12, Issue 3 Pages 25-28
Ji Hongnian, Liu Lian, Liao Zhenhuan, Jiang Zucheng

Abstract: Sample (1 g) was dissolved in 5 mL 2 M HCl with heating then diluted to 25 mL with water. A portion of the solution and aqueous 0.1% sodium diethyldithiocarbamate were mixed then injected into the flow injection system, merged with a stream of HCl/NH3/H2O buffer of pH 4.6, passed through a 125 cm mixing coil and pre-concentrated on a 100 mg carbon-silica gel column (2.8 cm). The column was washed with 2 mL water, 4.5 M HNO3 was introduced, the flow was stopped for 1 min and the analytes were eluted at 5.1 ml/min. The eluate was evaporated and the residue was dissolved in 2 M HNO3 for ICP-AES determination of Al, Cr, Cu, Fe and V. Enrichment factors for these elements were 9.6-12.6. Detection limits were at the ng/ml level, and the RSD (n = 7) for ppm level of metals were 2.3-5%. Recoveries were 83-100%. Some matrix interference was observed. Metal impurities could be determined at the µg/g level.
High purity Spectrophotometry Preconcentration Silica gel Buffer Interferences Stopped-flow

"Determination Of Vanadium By Flow Injection Analysis With Vanadium(V) - Ferrocyanate - Luminol Chemiluminescence System"
Fenxi Shiyanshi 1992 Volume 11, Issue 1 Pages 33-34
Lu, J.R.;Zhang, X.R.;Zhang, Z.J.

Abstract: Standard solution was treated with 0.10 mL of 1% K4(CN)6, 0.5 mL of 0.01 M HCl, 1.0 mL of 1% aluminum potassium sulfate, 1.0 mL of 0.01 M EDTA and water to 50 mL. The mixture was subsequently treated with 3 mM luminol solution and the luminescence intensity was measured. The calibration graph was rectilinear for 0.4 to 100 ng mL-1 of V and the detection limit was 0.2 ng mL-1; the coefficient of variation was 2% (n = 11). The method was applied to the analysis of water with recoveries from 96 to 105%.
Environmental Chemiluminescence

"Online Determination Of Trace Heavy Metals In Waters By ICP-AES Using A Recycling Nebulizing System With Flow Injection Solvent Extraction"
Fenxi Shiyanshi 1996 Volume 15, Issue 5 Pages 66-68
Cheng, X.H.;Zhou, J.M.;Liu, H.D.;Tang, Z.Y.;Shuai, Q.;Jin, Z.X.

Abstract: Sample (20 ml), was adjusted to pH 1 with HNO3 and heated for 10 min and cooled. The cooled solution was adjusted to pH 2.5 with ammonia water, 0.5 mL aqueous 2% ammonium 1-pyrrolidinecarbodithioate was added and the pH was re-adjusted to 2.5 with 5% HNO3. The mixture was diluted to 25 mL with water and a 240 µL portion of the diluted solution was injected into the flow injection liquid-liquid online extraction system of Shuai et al., (Dizhi Shiyanshi, 1996, in press), using an extraction coil (1.5 m x 0.8 mm i.d.) over 75 s, with IBMK for removal of metal impurities. The organic phase was transferred to the recycling nebulizing system for ICP-AES. Detection limits for Cd, Co, Cu, Fe, Mo, Ni and V were 0.1-2.2 µg/l, with RSD 3.2-7.6%. Recoveries were 93.5-104%. Sampling frequency was 20 runs per h.
Environmental Spectrophotometry Sample preparation Nebulizer MIBK Solvent extraction

"Simultaneous Multi-element Analysis And Matrix Effect Of Sodium Chloride By Flow Injection ICP-AES"
Guangpuxue Yu Guangpu Fenxi 1991 Volume 11, Issue 5 Pages 32-37
Zhang, Z.;Zeng, X.

Abstract: The determination of Cd, Cr, Fe, Mn, Ni, V, Ca, Co, Cu, Mg and Zn by ICP-AES combined with flow injection analysis. The best coefficient of variation and detection limits were obtained with 5- or 10-s integral times. The effects of a NaCl matrix on the elements were studied. The results show that the flow injection technique could reduce analytical signal drift and improve determination reproducibility. The matrix effects of NaCl varied with different r.f. power and the matrix effect of NaCl existed mainly in the evaporation - atomization - excitation process in the ICP.
Inorganic compound Spectrophotometry Multielement Signal drift Interferences

"Study Of The Effects Of Matrix And Acid In Flow Injection ICP-AES"
Guangpuxue Yu Guangpu Fenxi 1992 Volume 12, Issue 3 Pages 49-54
Chen, H.;Jiang, Z.C.;Zeng, Y.N.;Kong, L.Y.

Abstract: To study matrix and acid effects in flow injection ICP-AES, a PGS-2 plane-grating spectrograph was used (working conditions tabulated). Results showed that the introduction of 5 mg mL-1 of matrices (viz. Na, Ca, Fe and Zn) and acids (viz. HCl, HNO3 and H2SO4) caused a decrease in emission intensity of Cr, Mn, Ni, Cu, V, Cd and Zn, but no significant change in excitation temperature and electron density was observed. The matrix interference could be eliminated by adding an appropriate amount of the matrix elements into the carrier.
Spectrophotometry Interferences

"Chemiluminescence Analysis With Inorganic Coupled Reactions. 1. Determination Of Trace Vanadium With Hydrogen Peroxide - Sodium Thiosulfate - Luminol System"
Acta Chim. Sin. 1988 Volume 46, Issue 6 Pages 543-547
Zhang Zhu-Jun* Ma Wang-Bai Wang Ping

Abstract: The sample (50 to 100 ml) is mixed with 5 mL of acetate buffer solution (pH 2.5), and the solution is passed through a column (15 cm x 15 mm) of strongly basic anion-exchange material at a flow rate of 5 mL min-1. After washing the column with 50 mL of water, V is eluted with 20 mL of 0.6 M NaOH. The eluate is mixed with 5 mL of 0.1 mM H2O2 and 5 mL of 10 mM Na2S2O3 and adjusted to pH 3.5 with 4 M HCl. After adding 5 mL of HCl - K H phthalate buffer solution (pH 3.5), the solution is analyzed by using a chemiluminescence analyzer.. The chemiluminescence intensity is rectilinearly related to concentration. for 0.5 to 30 ppb of V; the detection limit is 0.43 ng mL-1. The coefficient of variation is 3.2% when determining 2 ppb of V. The method has been applied in the determination of V in water.
Environmental Ion exchange Chemiluminescence

"Catalytic Spectrophotometric Determination Of Vanadium By Flow Injection Analysis"
J. Chin. Chem. Soc. 1985 Volume 32, Issue 4 Pages 405-410
J. M. Hwang; J. C. Tsung; Y. M. Chen

Abstract: The water sample is mixed with solution of o-phenylenediamine(I) and of KBrO3 and tiron (at pH 3.2) that have been pre-mixed. The resulting solution is passed through a reaction coil (2.25 m) at 25°C before measurement of its absorbance at 440 nm. Vanadium catalyses the oxidation of I by BrO3-, and tiron acts as activator and as masking agent for foreign ions. Interference from Fe(III) can be prevented by adding NH4F to the carrier solution With 0.1 or 0.3 ppm of V, the coefficient of variation (n = 15) were 0.55 and 0.37%, respectively. Recovery is >96%.
Environmental Spectrophotometry Catalysis Interferences Tiron

"Measurement Of Trace Metallic Contaminants On Silicon Wafer Surfaces In Native And Dielectric Silicon Oxides By Vapor Phase Decomposition Flow Injection Inductively Coupled Plasma Mass Spectrometry"
J. Electrochem. Soc. 1993 Volume 140, Issue 4 Pages 1105-1109
J. Fucsko, S. S. Tan, M. K. Balazs

Abstract: The concentration of trace metals on silicon wafer surfaces was measured using a novel highly sensitive multi-element analytical method, called vapor phase decomposition flow injection inductively coupled plasma-mass spectrometry (ICP-MS). Metallic contaminants result in a deterioration in the performance and yield of semiconductor devices. ICP-MS uses hydrogen fluoride vapor to decompose and release metal contaminants from surface oxides. The metals are collected by scanning a small drop of dilute acid solution throughout the surface of the wafer and are measured by ICP-MS using flow injection sample introduction. As many as 60 elements can be determined with detection limits ranging from 108 to 1011 atom/cm2. ICP-MS has the potential to serve as a reference technique for the calibration of surface analytical methods, as well as offering an improved technique for measuring trace metals. One or more Si wafers were loaded into a specially constructed vapor-phase decomposition box containing a reservoir of HF solution The exposure time depends on the thickness of the oxide layer, 20 min for 15-30 .angstrom., 3-12 h for 2000-10 000 .angstrom.. A single drop of HF was then placed on the wafer surface and carefully rolled over the surface to extract the trace metals. The drop was transferred to a small sample tube and injected into the Ar ICP torch assembley with a cross-flow pneumatic nebulizer. Calibration was performed using multi-element standard solution For solution containing either 0.8 or 4.0 ppb of Mg, Cu, and Ni, and Cu the precision (n = 10) was ± 15% and ± 8%, respectively. The recovery of trace metals spiked on to bare Si wafers varied from 90-110% for Al, Cr, Fe, Ni and Na at surface concentration. of 5.67 x 1010-63.5 x 1010 atom/cm2. The recovery of Cu was 8.3% with the experimental conditions used. The detection limits were 108-109 atom/cm2 for Cr, Co, Fe, Pb, Mg, Mn, Ni, K, V, Zr, 2 x 1010 for Al and Fe and 1 x 1010 for Na. The procedure was applied to the determination of metal contaminants on bare Si wafers from different sources. Aluminum, Fe and Na are the most common metal contaminants.
Metal Inorganic compound Mass spectrometry Multielement

"Catalytic Determination Of Trace Elements By Flow Injection Analysis"
J. Flow Injection Anal. 1994 Volume 11, Issue 1 Pages 7-23
Teshima, N.;Nakano, S.;Kawashima, T.

Abstract: A review is presented of the use of catalytic reactions in FIA methods for trace analysis. Catalytic reactions are easily controlled in FIA by fixing the flow rate of the solution and the length of the reaction coil. Diagrams of the flow manifolds for Mn and V determinations are also presented. (56 references).
NIST 1643 Catalysis Review

"Application Of Sequential Injection - Wetting-film Extraction To The Photometric Determination Of Vanadium(IV) And Vanadium(V)"
J. Flow Injection Anal. 1996 Volume 13, Issue 2 Pages 148-159
Nakano, S.;Luo, Y.;Holman, D.A.;Ruzicka, J.;Christian, G.D.

Abstract: A 3 mL mixture of V(IV) and V(V) in 0.5 M HCl (final pH 1.5) was introduced at 1 ml/min into a six-port selection rotary valve sequential injection - wetting-film extraction manifold (diagram shown) for extraction (aspirating time for 3 min) on the inner flow-cell wall of the PTFE extraction coil (3.5 m x 0.8 mm i.d.) which was precoated with 0.4% N-cinnamoyl-N-(2,3-xylyl)hydroxylamine (I) in benzene and air-dried. After washing with 6 M HCl, 50 µL benzene was added to dissolve and elute the V(V)-I complex into a flow-through cell for detection at 546 nm. To determine V(IV), the mixture was oxidized to V(V) with 15 mM periodate solution before loading into the extraction coil for complex formation with I; with total V content known, the concentration of V(V) was obtained by subtraction. Calibration graphs for V(IV) and V(V) were linear from 0.05-0.3 µg/ml, with detection limits of 1 µM. Tolerance levels for Fe(III), Mo(VI) and W(VI) were 5 µg/ml and that of Sn(II) was 1 µg/ml. The sampling frequency was 15 runs/h.
Spectroelectrochemistry Sample preparation Sequential injection Solvent extraction

"Determination Of Trace Vanadium By Reversed-flow Injection Catalytic Spectrophotometry"
Lihua Jianyan, Huaxue Fence 1998 Volume 34, Issue 3 Pages 101-103
Liu Xiuping and Zhang Zhiqi

Abstract: A method for the determination of trace V by reversed-flow injection catalytic spectrophotometry was established. The method is based on the catalytic action of V on the oxidation-decoloration of rhodamine B by NaBrO3 with citric acid as activating agent in the presence of OP in H2SO4 medium. The interferences of Fe(III) and Cu(II) were eliminated by using cation resin exchange. The linear range was 10^-200 µg L-1, the detection limit 1.9 µg L-1, and the RSD 1.5%. The method was used for the determination of trace V in water samples with a recovery 90-104%.
Water Ion exchange Spectrophotometry Catalysis Reverse Interferences Resin

"Determination Of Dissolved Vanadium In Natural Waters By Flow Injection Analysis With Colorimetric Detection"
Limnol. Oceanogr. 1998 Volume 43, Issue 3 Pages 526-529
Shiller, Alan M., Lunjin Mao, and Jeramé Cramer

Abstract: A flow injection technique for the determination of dissolved V in natural waters utilizes the V-catalyzed oxidation of Bindschedler's green leuco base by bromate with tiron and tartrate as reaction activators. The reaction product is quantified colorimetrically. A chelator column of immobilized 8-hydroxyquinoline reduces matrix effects but can be eliminated if samples with a constant matrix are being analyzed. Using the chelator column, 1 mL of sample can be analyzed in <10 min with a detection limit of 0.2 nM. The method was used for the determination of dissolved V in river and estuarine waters.
Estuarine River Spectrophotometry Chelation 8-Hydroxyquinoline

"Studies On Spectrophotometric Catalytic Determination Of Trace Amounts Of Metals. 5. Spectrophotometric Determinations Of Trace Vanadium By Means Of Flow Injection Analysis Based On The Catalytic Oxidation Of Bindschedler's Green Leuco-base By Potassium"
Nippon Kagaku Kaishi 1981 Volume 1981, Issue 1 Pages 98-102
Kazuo HIRAYAMA, Nobuyuki UNOHARA

Abstract: A sensitive and simple method has been developed for the determination of trace vanadium by means of flow injection analysis based on the catalytic oxidation of Bindschedler's Green leuco base (4,4'-bis(dimethylamino)diphenylamine, BGL) by potassium bromate. A schematic diagram of the flow injection system is shown in Fig. 1. The reagent solutions of BGL and potassium bromate in reservoirs A and B, respectively, were pumped out using a peristaltic pump into the manifold. A sample solution, 20 µL, was introduced into the carrier reagent solution via syringe loading sample injector. The introduced sample was then transported through the reaction coil (poly (tetrafluoroethylene), inner diameter 0.56 mm), and BGL was oxidized to Bindschedler's Green (BG) which showed a maximal absorbance at 725 nm. The absorbance of BG was monitored at 725 nm by spectrophotometer equipped with a flowthrough cell (volume 200 µL, light path 5 mm), and was continuously recorded. Some factors that influence the flow injection system, pumping rate, reaction coil length, sample volume and sampling rate, were studied systematically. Under the conditions of BGL: 1.6 x 10^-3 mol/L, potassium bromate: 6.4 x 10^-2 mol/L, pH: 3.8 and temperature 25°C with pumping rate 1.6 mL/min and reaction coil length 5 m, a linear relationship was obtained between the peak height (absorbance)and the concentration of vanadium(IV) in the range of 0-80 ppb. In this method, the detection time after sample injection was ~40 s, and a sampling rate of 60 samples/h was achieved.
Spectrophotometry Optimization

"Selective Accumulation Of Elements By Plants Synthesizing Saponin"
Appl. Biochem. Microbiol. 1997 Volume 33, Issue 6 Pages 641-642
LOVKOVA M.JA., PONOMAREVA S.M., SOKOLOVA S.M., SHELEPOVA O.V., BUSUK G.N.

Abstract: Elemental compositions (including 4 macroelements and 16 microelements) of 15 medicinal plant species synthesizing saponin were determined by atomic absorption spectrometry of wet-ashed and dry-ashed samples on a Z-6000 spectrophotometer (Hitachi, Japan) and a FIA-Star flow injection analyzer (Tecator, Sweden), the. These species were shown to selectively accumulate nine elements (Fe, Cr, Zn, Mn, Co, Al, Cu, Ba, and V) whose levels were considerably (more than 30-fold) higher than the respective average levels for plants growing in the same climatic zones. The ability of saponin-synthesizing species to accumulate certain elements, as well as low variance of the concentrations of the majority of such elements combined with high coefficients of correlation between them, suggest that these species have a specific elemental composition.
Plant Spectrophotometry Tecator

"Robust Photometric Detector For Process Analysis"
Process Control Qual. 1992 Volume 2, Issue 3 Pages 249-255
G.D. Marshall, M.J.C. Taylor, D.E. Barnes and S.J.S. Williams

Abstract: The instrument described and illustrated incorporates a light-emitting diode, a transmitter to modulate the light output and a receiver to detect the modulated light. Two flow cells are used; one is formed by drilling a hole (1.1 mm diameter) through the body of the diode, and the other, of Z-shaped design, has a diameter of 0.5 mm. The apparatus has been used in a flow injection arrangement for the determination of V in samples from a solvent extraction V purification plant; ascorbic acid in 1% H2SO4 is used as carrier stream to reduce V(V) to V(IV), which is determined at 760 nm. The Z-shaped cell is subject to refractive index effects, which can be overcome by matrix matching or blank subtraction. Results obtained with the analyzer agreed with those of redox titration.
Industrial Spectrophotometry Process monitoring Light emitting diode Flowcell Refractive index Method comparison

"Pneumatic Nebulizer As A Dilution Chamber In A Flow Injection System For Multielement Analysis By ICP-MS"
Quim. Nova 1998 Volume 21, Issue 4 Pages 405-409
Gomes Neto, Jos&eacute; Anchieta; Silva, Jos&eacute; Bento B.; Rodrigues Neto, Renato; Curtius, Adilson Jos&eacute;; Souza, Ivan G.

Abstract: An automatic dispenser based on a flow injection system used to introduce sample and anal. solution into an inductively coupled plasma mass spectrometer through a spray chamber is proposed. Anal. curves were constructed after the injection of 20 to 750 µL aliquots of a multielement standard solution (20.0 µg L-1 in Li, Be, Al, V, Cr, Mn, Ni, Co, Cu, Zn, As, Se, Sr, Ag, Cd, Ba, Tl, Pb) and the acquisition of the integrated transient signals. The linear concentration. range could be extended to ~five decades. The performance of the system was checked by analyzing a NiST 1643d reference material. Accuracy could be improved by the proper selection of the injected volume Besides good precision (relative standard deviation <2%), the results obtained with the proposed procedure were closer to the certified values of the reference material than those obtained by direct aspiration or by injecting 125 µL of several anal. solutions and samples.
NIST 1643 Mass spectrometry Dilution Nebulizer Reference material