Copper spectrophotometric analysis

Triphenyl-2,2, 2"-tripyridylgives colored, complex, copper(I) ions suitable for spectrophotometric analysis (307). Complexes CuBr-(triars) [triars = bis-(2-dimethylarsinophenyl)methylarsine] (142), CuI[MeAs (CH2)3AsMe2 2] (21), and CuCl Me(CS)CH2(CS)CH2(CS)Me (123) have also been prepared. These complexes are monomeric and analogs of the CuXLg complexes. It is possible that tri-(2-pyrryl)-phosphine is tridentate (via two nitrogen atoms and the phosphorus atom) in its chloro- and bromocopper complexes obtained from the oopper(II) salts. 

Gamble, D. S., Underdown, A. W., and Langford, C. H. (1980). Copper(n) titration of fulvic acid ligand sites with theoretical, potentiometric, and spectrophotometric analysis. Anal. Chem. 52, 1901-1908. 

The thiocyanate method has been used for determining cobalt in vitamin B12 [94], steel [24,94], and nickel [25]. Cobalt present in considerable amounts in alloys with aluminium, nickel, chromium, manganese, copper, and iron was determined by the differential spectrophotometric analysis [95]. 

It has been reported that y3-CD could improve the selectivity of the color reactions of various metal ions with triphenylmethane, xanthene acid dyes and some other coloring reagents. The effect of fi-CD on the association compound system of metal (Mo, Zn, Co)-thiocyanate basic dyes such as malachite green, crystal violet, rhodamine B, rhodamine 6G and butyhhodamine B, has been investigated and the result shows that /3-CD could contribute to a more sensitive and stable system which improve the solubility of the basic dyes and produce a favorable microenviromnent for the color reactions [63]. /3-CD could be employed to solubilize the 1,2-amino anthraquinone in water due to the formation of inclusion complex which acts as a ligand for metal ions could be used for the determination of palladium at trace levels by spectrophotometry. In the spectrophotometric determination of microamounts of Zn based on the Zn-dithizone color reaction, -CD could increase the apparent molar absorptivity at 538 nm by 8.37 times. In the presence of cr-CD, the determination sensitivity of copper in leaves based on the color reaction of Cu(II) and mesotetrakis (4-methoxy-3-sulfophenyl) porphyrin was enhanced by 50% in the spectrophotometric analysis [64,65]. 

J.R. Spies, D.C. Chambers, Spectrophotometric analysis of amino acids and peptides with their copper salts, J. Biol. Chem. 191 787-797 (1951)... 

The advantages of atomic absorption techniques as opposed to spectrophotometric analysis for the determination of metals are that the former are amenable to multielement analysis and can be automated. There is some evidence that ashing polymers in silica crucibles rather than platinum can lead to up to 10% losses of elements such as copper by adsorption within the silica matrix to produce a compound that is not extractible by subsequent acid leaching. This does not occur when ashing is carried out in platinum. If silica crucibles are used then a magnesium oxide ashing aid should be employed as is demonstrated in the method for determining down to 0.1 ppm of copper in polyolefins, (Method 72). 

Some problems in the spectrophotometric analysis of dyes are discussed elsewhere in this paper, including the plating out of Evans blue on absorption cell windows the nonadditivity of the spectra of certain dyes the effect of copper upon a direct yellow... 

S-hydroxyquinoline, oxine, C9H7ON. Light brown needles, m.p. 15-16 C. Forms insoluble complexes with metals. The solubilities of the derivatives vary with pH, etc. and hence oxine is widely used in analysis. Used for estimating Mg, Al, Zn and many other metals. Many oxinates are extracted and the metal is estimated spectrophotometrically. Derivatives, e.g. 2-meIhyl tend to be specific, for, e.g.. Copper derivatives are used as fungicides. 

Nickel also is deterrnined by a volumetric method employing ethylenediaminetetraacetic acid as a titrant. Inductively coupled plasma (ICP) is preferred to determine very low nickel values (see Trace AND RESIDUE ANALYSIS). The classical gravimetric method employing dimethylglyoxime to precipitate nickel as a red complex is used as a precise analytical technique (122). A colorimetric method employing dimethylglyoxime also is available. The classical method of electro deposition is a commonly employed technique to separate nickel in the presence of other metals, notably copper (qv). It is also used to estabhsh caUbration criteria for the spectrophotometric methods. X-ray diffraction often is used to identify nickel in crystalline form. 

Comparative studies of the widely employed spectrophotometric readings at the Soret and Q bands (405 and 630 nm, respectively) and the elemental analysis of copper and nitrogen showed that the spectrophotometric assay based only on the Soret band can overestimate the purity of a preparation. Erroneous data were attributed to an increase in absorptivity at the Soret band when other colored compounds like metal-free analogs and carotenoids are present. Indeed, copper-free chlorin e6 exhibits a specific absorbance 3.6 times greater than that of its coppered counterpart. Therefore, measurements at the Q band (630 mn) and the establishment of the S Q ratio are preferred. 

After adjusting to 2 mol 1 1 in hydrochloric acid, 500 ml of the sample is adsorbed on a column of Dowex 1-XS resin (Cl form) and elution is then effected with 2 M nitric acid. The solution is evaporated to dryness after adding 1M hydrochloric acid, and the tin is again adsorbed on the same column. Tin is eluted with 2 M nitric acid, and determined in the eluate by the spectrophotometric catechol violet method. There is no interference from 0.1 mg of aluminium, manganese, nickel, copper, zinc, arsenic, cadmium, bismuth, or uranium any titanium, zirconium, or antimony are removed by ion exchange. Filtration of the sample through a Millipore filter does not affect the results, which are in agreement with those obtained by neutron activation analysis. 

A spectrophotometric method that does not use condensation with sulfuric acid was proposed by Mopper and Gindler [157]. The method used the copper (I) complex with 2,2-bicinchoninate to form a colour with simple sugars, with a hydrolysis step which is included to make simple sugars from the polysaccharides. Thus the analysis of two aliquots, one of them hydrolysed, would yield values for both simple and combined sugars. 

Analytical methods employed in soil chemistry include the standard quantitative methods for the analysis of gases, solutions, and solids, including colorimetric, titrimetric, gravimetric, and instrumental methods. The flame emission spectrophotometric method is widely employed for potassium, sodium, calcium, and magnesium barium, copper and other elements are determined in cation exchange studies. Occasionally arc and spark spectrographic methods are employed. 

Reaction of Cytochrome cIinn with Bis(ferrozine)copper(II) Knowledge of the redox properties of cytochrome c was an encouragement to initiate a kinetics investigation of the reduction of an unusual copper(II) complex species by cyt c11. Ferrozine (5,6-bis(4-sulphonatophenyl)-3-(2-pyridyl)-1,2.4-triazine)286 (see Scheme 7.1), a ligand that had come to prominence as a sensitive spectrophotometric probe for the presence of aqua-Fe(II),19c,287 forms a bis complex with Cu(II) that is square pyramidal, with a water molecule in a fifth axial position, whereas the bis-ferrozine complex of Cu(I) is tetrahedral.286 These geometries are based primarily upon analysis of the UV/visible spectrum. Both complexes are anionic, as for the tris-oxalato complex of cobalt in reaction with cytochrome c (Section 7.3.3.4), the expectation is that the two partners will bind sufficiently strongly in the precursor complex to allow separation of the precursor formation constant from the electron transfer rate constant, from the empirical kinetic data. 

Equilibrium studies involving double-stranded trihelicates have demonstrated the co-operative nature of metal ion binding. A spectrophotometric titration investigation of the stepwise binding of copper(I) to a (substituted) tris-bipyridyl ligand system of the present type in dichloromethane-acetonitrile (1 1) indicated the formation of a single, well-defined product. From analysis of the data, the self-... 

Several experiments have been carried out on samples of natural waters and industrial wastewaters (12 for Cu, 9 for Hg and 14 for Fe), with standard addition for some samples [55]. The analysis of the samples was performed both by a reference method (graphite furnace AAS for copper and iron, cold vapour AAS for Hg), and by the proposed spectrophotometric method. 

C.C. Oliveira, R.P. Sartini, B.F. Reis, E.A.G. Zagatto, Multicommutation in flow analysis. Part 4. Computer assisted splitting for spectrophotometric determination of copper and zinc in plants, Anal. Chim. Acta 332 (1996) 173. 

D. Vendramini, V. Grassi, E.A.G. Zagatto, Spectrophotometric flow injection determination of copper and nickel in plant digests exploiting differential kinetic analysis and multi site detection, Anal. Chim. Acta 570 (2006) 124. 

R. Kuroda, T. Mochizuki, Continuous spectrophotometric determination of copper, nickel and zinc in copper-base alloys by flow-injection analysis, Talanta 28... 

J.A. Sweileh, On-line flow injection solid sample introduction digestion and analysis spectrophotometric and atomic absorption determination of iron, copper and zinc in multi-vitamin tablets, Microchem. J. 65 (2000) 87. 

T. Blanco, N. Maniasso, M.F. Gine, A.O. Jacintho, Liquid-liquid extraction in flow injection analysis using an open-phase separator for the spectrophotometric determination of copper in plant digests, Analyst 123 (1998) 191. 

R. Kuroda and T. Mochizuki, Continuous Spectrophotometric Determination of Copper, Nickel and Zinc in Copper-Base Alloys by Flow Injection Analysis. Talanta, 28 (1981) 389. 

R. M. Smith and T. G. Hurdley, Spectrophotometric Determination of Copper as a Dithiocarbamate by Flow Injection Analysis. Anal. Chim. Acta, 166(1984)271. 

A. T. Faizullah and A. Townshend, Spectrophotometric Determination of Copper by Flow Injection Analysis with an On-Line Reduction Column. Anal. Chim. Actay 172 (1985) 291. 

This field provides a brief description of the suggested monitoring and analysis method for quantitative determination of a particular substance. For example, a method for quantitative determination has been developed for cadmium, copper, manganese, and lead in water by means of co-precipitation with zirconium hydroxide followed by subsequent analysis by atomic adsorption spectrometry. An Inductively Coupled Plasma-Atomic Emission Spectrophotometric method has been employed by the Environmental Protection Agency (EPA Method 200.7) for the determination of dissolved, suspended, or total elements in drinking water, surface water, and domestic and industrial wastewaters. 

S.W. Kang, T. Sakai, N. Ohno, and K. Ida. Simultaneous spectrophotometric determination of iron and copper in semm with 2-(5-bromo-2-pyridylazo)-5-(N-propyl-N-sulphopropylamino) aniline by flow-injection analysis. Analytical Chimica Acta 261 197-206,1992. 

FIGURE 1,6 Example of manifolds developed for flow injection speciation analysis, (a) Manifold of the reversed FIA system for speciation of chromium with pH measurements and spectrophotometric detection, q—peristaltic pumps, V—injection valves, L— reaction coil, M.E.—pH glass electrode. (Adapted from Ruz, J. et al. 1986. J. Autom. Ghent. 8 70-74.) (b) Manifold of branched FIA system for simultaneous biamperomet-ric determination of nitrate and nitrite. (Cd)Cu—reductive column with copperized cadmium, L—mixing coils. (Adapted from Trojanowicz, M., W. Matuszewski, and B. Szostek. 1992. Anal. Chim. Acta 261 391-398.) (c) Example signal recordings obtained in the FIA system shown in (b) 1-6—standard solutions, A-I—natural water samples. Concentration in standard solutions 1—0.075 2—0.050 3—0.025 mM nitrate and 4—7.5 5—5.0 6—2.5 pM nitrite. 

Trojanowicz, M. 2008. Advances in Flow Analysis. Weinheim, Germany Wiley-VCH. Tsen, C. C. 1961. An improved spectrophotometric method for the determination of tocopherols using 4,7-diphenyl-lO-phenanthroline. Anal. Chem. 23 849-851. Tutem, E., R. Apak, E. Gunayd, and K. Sozgen. 1997. Spectrophotometric determination of vitamin E (a-tocopherol) using copper(II)-neocuproine reagent. Talanta 44 249-255. 

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