Hydroxylamines analytical chemistry

Figure 9 A synthetic mixture of water-soluble carboxylic acids separated by anion-exchange chromatography. Column 0.3 cm x 300 cm Diaoion CA 08, 16-20 p (Mitsubishi Kasei Kogyo). Eluant 200 mM HC1. Detection reaction with Fe3-benzohy-droxamic acid-dicyclohexy carbodiimide-hydroxylamine perchlorate-triethyl amine with absorbance at 536 nm. Analytes (1) aspartate, (2) gluconate, (3) glucuronate, (4) pyroglutamate, (5) lactate, (6) acetate, (7) tartrate, (8) malate, (9) citrate, (10) succinate, (11) isocitrate, (12) w-butyrate, (13) a-ketoglutarate. (Reprinted with permission from Kasai, Y., Tanimura, T., and Tamura, Z., Anal. Chem., 49, 655, 1977. 1977 Analytical Chemistry).

Many of the 3-hydroxytriazene derivatives produced by diazo-coupling onto N-alkyl or A-aryl hydroxylamines decompose explosively above their m.p.s. However, the heavy metal derivatives are stable and used in analytical chemistry. 

Elemental composition H 9.15%, N 42.41%, O 48.44%. Hydroxylamine may be measured by coulometric titration to a potentiometric end point using a coulometric titration cell. A standard solution of bromine may be used as oxidizer in the redox reaction. (Skoog, D. A., D. M. West, and F. J. HoUer. 1992. Fundamentals of Analytical Chemistry, 6th ed. pp. 467, Orlando Saunders College Publishing)... 

The precipitation of cuprous acetylide was introduced into analytical chemistry for the quantitative determination of copper. Since cupric acetylide was dangerous to handle, Makowka [108] worked out a method in which cupric salts are previously reduced, e.g. with hydroxylamine, to cuprous salts, when the acetylide is precipitated. Cuprous salts in a solution of hydroxylamine are employed as reagents for acetylene (e. g. Pietsch and Kotowski [114]). 

Table 2.4 Determination of bromate in the presence of hypochlorite ions evaluation of the hydroxylamine hydrochloride efficiency. Concentrations are in gg/L (after Ingrand et at, 2002). Reprinted from Trends in Analytical Chemistry, Vol. 21, No. 1, Ingrand er a/., Determination of bromate... , pp. 1-12,2002, with permission from Elsevier...

The creation of cuprous acetylide has been suggested as a quantitative method for determination of copper in analytical chemistry [33]. Cuprous acetylide is produced in ammoniacal environments in the presence of hydroxylamine, even at very low concentrations of acetylene gas. It is on the basis of the formation of a brown precipitate of cuprous acetylide that a sensitive method for detection of acetylene was devised [58]. 

First accounts of the condensation of hydroxylamines with sugars can be found in the 1880s [39]. Owing to the lack of analytical methods to determine molecular structures, these early condensations were used for the characterization of sugars, the best known example of this chemistry is the Wohl degradation [40]. Here, we cover the more recent applications and characterization of O-aUcyl-N-glycosyl oxyamines. 

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