Reaction of gallocyanine methyl ester with uranyl ions

1984 ◽  
Vol 49 (9) ◽  
pp. 2070-2077
Author(s):  
Milan Kotouček ◽  
Marta Hrbková
Keyword(s):  
Methyl Ester ◽  
Equilibrium Constants ◽  
Conditional Stability ◽  
Uranyl Ions ◽  
Optimum Conditions ◽  
Relative Standard ◽  
Conditional Stability Constants ◽  
Concentration Curves ◽  
Coordination Reaction

The reaction of gallocyanine methyl ester with uranyl ions was studied spectrophotometrically in slightly acid or neutral solutions in 40% (m/m) ethanol. A violet complex of UO2L2 is formed at pH > 5. The conditional stability constants of the complex in the pH 6 - 7.4 range and the equilibrium constants of the coordination reaction were derived from the concentration curves and continuous variations curves. The optimum conditions were sought for the spectrophotometric determination of uranium based on the occurrence of the UO2L2 complex. The relative standard deviation obtained for a uranium concentration of 106 μg l-1 was sr = 2.13%.

Reactions of gallocyanine methyl ester with gallium(III) and indium(III) ions

1982 ◽  
Vol 47 (7) ◽  
pp. 1950-1963 ◽  
Author(s):  
Milan Kotouček ◽  
Josef Růžička ◽  
Pavla Vaculíková
Keyword(s):  
Methyl Ester ◽  
Stability Constants ◽  
Equilibrium Constants ◽  
Photometric Determination ◽  
Conditional Stability ◽  
Conditional Stability Constants

Reactions of gallocyanine methyl ester with gallium(III) and indium(III) ions in solutions in 15% (m/m) ethanol were studied spectrophotometrically. At pH 1.7-6.5, the GaL, GaL2, and Ga(OH)L3 complexes are formed; in the case of indium, the In(OH)2L2 and In(OH)L3 complexes appear at pH 4-6.5, and InL3B2 in tartrate solutions. The conditional stability constants and the equilibrium constants of the coordination equilibria were calculated, and procedures were worked out for a photometric determination of gallium and for a chelatometric determination of gallium and indium using gallocyanine methyl ester as metallochromic indicator.

Reactions of gallocyanine methyl ester with germanium(IV), tin(IV) and lead(II) ions

1984 ◽  
Vol 49 (9) ◽  
pp. 2078-2095
Author(s):  
Milan Kotouček ◽  
Josef Růžička
Keyword(s):  
Methyl Orange ◽  
Methyl Ester ◽  
Equilibrium Constants ◽  
Colour Change ◽  
Photometric Determination ◽  
Conditional Stability ◽  
Acid Solutions ◽  
Complexation Reactions ◽  
Conditional Stability Constants

The reactions of gallocyanine methyl ester with germanium(IV) and tin(IV) in 7.7% (m/m) ethanol and with lead(II) in 15.5% ethanol are studied spectrophotometrically. In slightly acid solutions, complexes of GeL3 (pH 2.5-6.5), SnL2 and SnL3 (pH 1.7-6 in the presence oftartaric acid), and PbL and PbL2 (pH 4-7) are formed. The conditional stability constants of the complexes and the equilibrium constants of the complexation reactions are calculated and procedures are suggested for the photometric determination of tin and for the chelometric determination of lead using visual or photometric indication with gallocyanine methyl ester as metallochromic indicator (colour change from red-violet to blue). A gallocyanine methyl ester-methyl orange screened indicator proved useful for the visual determination of lead, showing an expressive colour change from brown to green.

Spectrophotometric study of the reaction of dyes of the alizarin green series with indium(III) ions in the presence of cationic tensides

1980 ◽  
Vol 45 (3) ◽  
pp. 703-714 ◽  
Author(s):  
Nguyen Truong Son ◽  
Eduard Ružička
Keyword(s):  
Equilibrium Constants ◽  
Ternary Systems ◽  
Spectrophotometric Study ◽  
Ternary Complexes ◽  
Conditional Stability ◽  
Acid Media ◽  
Weakly Acid ◽  
Cetyl Pyridinium ◽  
Conditional Stability Constants

The reactions of four dyes of the alizarin green series with indium(III) ions were studied. In weakly acid media of pH 4-6.5, binary InL and InL2 complexes are formed in solution. In the presence of cationic tensides containing cetyltrimethylammonium and cetyl pyridinium, defined ternary complexes, InL3S6, are formed in the solution. The conditional stability constants of the binary In-L complexes and the equilibrium constants of the studied complexing ternary systems were calculated and a procedure for the photometric and chelometric determination of indium was proposed.

Reactions of gallocyanine methyl ester with vanadates and molybdates

1980 ◽  
Vol 45 (12) ◽  
pp. 3302-3312
Author(s):  
Milan Kotouček ◽  
Marie Barešová ◽  
Nguyen Truong Son
Keyword(s):  
Methyl Ester ◽  
Equilibrium Constants ◽  
Photometric Determination ◽  
Acidic Solutions ◽  
Concentration Curves

Reactions of gallocyanine methyl ester with vanadates and molybdates were examined spectrophotometrically in weakly acidic solutions in 10% (m/m) ethanol. Vanadates form the VO2L2, VO2(OH)L, and VO3L complexes at pH 3-6.5, molybdates form the MoO2L2 and MoO3L complexes at pH 1.5-4.4 and pH 3-5.3, respectively. The equilibrium constants of the systems concerned were calculated from the data of the concentration curves. Use has been made of the formation of the MoO2L2 complex for photometric determination of molybdenum.

Rapid Determination of Sulfite by Flow Injection Analysis Based on Fuchsin′s Addition

2013 ◽  
Vol 295-298 ◽  
pp. 950-953 ◽  
Author(s):  
Dong Yuan ◽  
Da You Fu ◽  
Wen Yuan Tan
Keyword(s):  
Flow Injection ◽  
Addition Reaction ◽  
Rapid Determination ◽  
Sampling Rate ◽  
Optimum Conditions ◽  
Linear Calibration ◽  
Relative Standard ◽  
Replicate Measurements ◽  
Good Agreement

A rapid spectrophotometric method for flow injection determination of sulfite in tan wastewater is described. The proposed method was based on the addition reaction of sulfite with fuchsin in Na2B4O7-NaOH medium. The optimum conditions allow a linear calibration range of 0.01-1.20 μg ml-1 SO32-. The detection limit is 0.0023μg ml-1 (S/N=3), and the relative standard deviation for night replicate measurements is 1.1% for 0.5μg ml-1 of sulfite. The sampling rate is 60 samples h-1. The procedure has been applied to the determination of sulfite in tan wastewater. The results were in good agreement with those obtained by pararosaniline method.

scholarly journals Determination of Organophosphorous Pesticide Phosphamidon in Environmental Water with Luminol Chemiluminescence Detection

2009 ◽  
Vol 92 (3) ◽  
pp. 914-918 ◽  
Author(s):  
Aifang Li ◽  
Xiaoyu Liu ◽  
Juan Kong ◽  
Haoyu Hu ◽  
Linghui Sun ◽  
...  
Keyword(s):  
Sodium Dodecyl ◽  
Sodium Dodecyl Benzene Sulfonate ◽  
Environmental Water ◽  
Optimum Conditions ◽  
Chemiluminescence Method ◽  
Luminol Chemiluminescence ◽  
Relative Standard ◽  
Organophosphorous Pesticide ◽  
Dodecyl Benzene Sulfonate

Abstract A novel chemiluminescence method has been developed for the determination of the organophosphorous pesticide phosphamidon in environmental water samples, based on the reaction of phosphamidon with luminolH2O2 in an alkaline medium using sodium dodecyl benzene sulfonate as the enhancer. Under optimum conditions, the increased chemiluminescence intensity was proportional to the concentration of phosphamidon in the range of 0.011.0 g/mL and the detection limit was 0.0038 g/mL (3). The relative standard deviation was <2 for 0.5 g/mL phosphamidon (n = 11). The proposed method was applied to the determination of phosphamidon residue in an environmental water sample with satisfactory results. Further study was focused on the mechanism of phosphamidon, and a possible mechanism was proposed.

scholarly journals A Highly Sensitive Spectrofluorometric Method for the Determination of a New Antidepressant Drug, Reboxetine, in Tablets

2006 ◽  
Vol 89 (4) ◽  
pp. 972-975 ◽  
Author(s):  
ArmaĞan Önal
Keyword(s):  
Antidepressant Drug ◽  
Fluorescence Emission ◽  
Calibration Graph ◽  
Control Analysis ◽  
Optimum Conditions ◽  
Highly Sensitive ◽  
Relative Standard ◽  
Spectrofluorometric Method ◽  
Interday Precision

Abstract A highly sensitive, selective, and rapid spectrofluorometric method has been developed for the determination of reboxetine (REB) in tablets. The method is based on derivatization with 7-chloro-4-nitrobenzofurazan. The product showed an absorption maximum at 476 nm and a fluorescence emission peak at 533 nm in ethyl acetate. The optimum conditions of the reaction were investigated, and it was found that the reaction proceeded quantitatively at pH 8.5, 70C in 5 min. The calibration graph is rectilinear over the range of 0.02-0.40 μg/mL. The relative standard deviation values for intraday and interday precision were 0.40-0.93 and 0.54-1.37%, respectively. The proposed method was applied to the assay of REB in tablets. Mean recovery of REB from the tablets ranged between 99.91-100.20%. The results were compared statistically with those obtained by a method reported in the literature. The method is sensitive, simple, and selective, and can be used for routine quality control analysis.

Determination of Aspartame in Beverages Using an Alcohol Oxidase Enzyme Electrode

1989 ◽  
Vol 72 (1) ◽  
pp. 30-33
Author(s):  
Vicki J Smith ◽  
Richard A Green ◽  
Thomas R Hopkins
Keyword(s):  
Liquid Chromatography ◽  
Standard Deviation ◽  
Methyl Ester ◽  
Alcohol Oxidase ◽  
Ester Group ◽  
Oxygen Electrode ◽  
Artificial Sweetener ◽  
Relative Standard ◽  
Oxidase Enzyme

Abstract A new method for the determination of the artificial sweetener aspartame is described. α-Chymotrypsin is used to cleave the methyl ester group of aspartame, producing methanol hydrolytically. The methanol is detected using an electrode which is constructed by physically trapping yeast alcohol oxidase enzyme at the tip of a dissolved oxygen electrode. The decrease in oxygen concentration, which occurs as methanol is enzymatically oxidized to formaldehyde, is measured amperometrically. Aspartame levels in diet soft drinks as determined by the proposed method and by liquid chromatography are in excellent agreement. The relative standard deviation of the measurements is 0.83%. The methanol present in diet cola as a result of aspartame degradation can also be measured by using the electrode without α-chymotrypsin.

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