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Showing papers on "Color reaction published in 1978"


Journal ArticleDOI
TL;DR: A proposed reference method for serum creatinine has been developed under the auspices of the Committee on Reference Methods and Reference Materials of the Canadian Society of Clinical Chemists and demonstrated a statistically significant high bias in interlaboratory studies in which this procedure was used for reference.

25 citations



Journal ArticleDOI
TL;DR: 6- Oxo-prostaglandin F1a produced a distinctive yellow chromogen on thin-layer chromatographic silica gel plates sprayed with an anis-aldehyde-sulphuric acid reagent; the colour reaction is specific to 6-oxo-PGF1a and some structurally related prostaglandins.

15 citations


Journal ArticleDOI
TL;DR: An oligomeric mixture of poly(vinyl acetate) (PVAc) was subjected to preparative gel-permeation chromatography, yielding pure n-mer in the range of n=4-14 as mentioned in this paper.
Abstract: An oligomeric mixture of poly(vinyl acetate) (PVAc) was subjected to preparative gel-permeation chromatography, yielding pure n-mer in the range of n=4—14. These n-mers, fractionated poly (vinyl acetate), and derived poly (vinyl alcohol) were used to study their color reaction with iodine in order to find the lower limits of the degree of polymerization for these reactions. In the poly(vinyl acetate)—iodine reaction the red-violet color began to appear at 12-mer. Tetradecamer was not long enough for the blue-color reaction of poly(vinyl alcohol)—iodine.

14 citations


Journal ArticleDOI
TL;DR: In this paper, a simple, rapid, and sensitive spectrophotometric micro determination of cadmium in aqueous solution was carried out at pH 12.3 ± 0.2.

14 citations


Journal ArticleDOI
TL;DR: In this article, the Gibbs reaction was used for the determination of the optimum conditions for the photometric procedure and the optimum pH range is 8.0-10.0, obtained with a suitable buffer.
Abstract: Indophenols and indophenolates resulting from the Gibbs reaction were prepared in the pure state and their properties studied under the conditions used in the photometric reactions. The results obtained and previous investigations allowed determination of the optimum conditions for the photometric procedure. Reproducible results are obtained when 2×10−6–2×10−5 M phenol reacts with a 30–50∶1 ratio of the reagent. The optimum pH range is 8.0–10.0, obtained with a suitable buffer. It is not possible to use a glycocoll buffer (quantitative reaction with the reagent) and ammoniacal buffers cannot be used for quantitative purposes. If extraction into an organic solvent is necessary, 1-butanol should be used without previous acidification of the reaction mixture. The first step of the colour reaction is the formation of the corresponding quinoneimine. Two molecules of this reactive species react immediately with one molecule of phenol.

11 citations


Journal ArticleDOI
TL;DR: A procedure is described that enables use of the p -phenylphenol color reaction to determine acetaldehyde in the presence of formaldehyde, applicable to blochemical reactions using tissue preparations.

9 citations


Journal ArticleDOI
TL;DR: In this paper, a spectrophotometric and chemical evaluation of reported interferences for three iron reactions for the determinations of serum cholesterol has been presented, and it has been shown that all three reactions are affected by various interfering substances, such as 2-thiouracil, nitrate, azide, bromide, diethylstilbesterol, and steroids.

5 citations


Journal ArticleDOI
TL;DR: In this paper, a comparison of thin layer chromatographic und UV-VIS data of the dyes formed by the oxidation of hydroxyproline and the pyrrole colour reaction is made probable.
Abstract: With the as yet unexplained chloramine-T-oxydation of hydroxyproline the formation of pyrrole-2-carboxylic acid and pyrrole could be established. On the oxydation with peroxyde as well as with chloramine-T pyrrole is the starting base for the colour reaction with Ehrlichs reagent. From a comparison of thin layer chromatographic und UV-VIS data of the dyes formed by the oxidation of hydroxyproline and the pyrrole colour reaction the formation of a dipyrrylphenylmethene salt and ms-tetra-(4-dimethylaminophenyl)-porphin is made probable.

3 citations


Journal ArticleDOI
TL;DR: The first chemical explanation on the titled reaction and a brief survey on the chemistry of a homologous series of I (I, II, and III) toward sulfuric acid are described.
Abstract: Retinoic acid (vitamin A acid) (I) has long been recognized as one of the most interesting members of the retinoid family (1). A quantitation method of I was proposed by KAWASAKI et al. who estimated an absorptivity of coloration developed by 74% sulfuric acid (2). The color was found to be stable in sulfuric acid, persisting for several hours at room temperature, so they used the method for assay of I in animal tissues. However, since no exact chemical approaches have been done on this color reaction and many aspects remain mostly unexplored, it seems desirable that the mechanism of this reaction should be better understood, so that the method may be qualified as a highly selective method of analysis. Furthermore, the investigation on this subject is expected to afford a great deal of knowledges on the chemistry of conjugated polyenoic acids, because little is known about their behavior toward strong acids. As an extension of model reactions, which were carried out previously on conjugated trienoic acid (II) (3) and tetraenoic acid (III) (4), this report describes the first chemical explanation on the titled reaction and a brief survey on the chemistry of a homologous series of I (I, II, and III) toward sulfuric acid.

3 citations


Journal ArticleDOI
TL;DR: This test seems to be useful for estimation of phenolic and indolic compounds in urine of patients with increased production of compounds of this nature, particularly in some tumors.

Patent
14 Nov 1978
TL;DR: In this paper, Antibiotic aculeacin DUPSILON has been used for the characterization of lower alchohols and white neutral substance, showing a peak at 278nm.
Abstract: PURPOSE:Antibiotic aculeacin DUPSILON. Characteristics thereof are as follows?elementary analysis, C 57.55%, H 8.32%, N 8.94%; molecular weight by the Rast method, 1265; m.p. 159-162 deg.C; specific rotation [alpha] D =-46.5 deg.(C=0.25, methanol); color reaction; positive to Pauly's reaction, etc., quasi-positive to Molisch's reaction, etc. negative to ninhydrin reaction, etc.; soluble in lower alchohols, slightly soluble in ethyl acetate, hardly soluble in acetone, etc.; white neutral substance; UV absorption spectrum shows a peak at 278nm; etc

Journal ArticleDOI
01 Feb 1978-Steroids
TL;DR: In this paper, the color reaction of cholesterol with trichloroacetic acid and antimony-trichloride was examined to elucidate its reaction mechanism, and the relationship between the color reagent and the formation of dimeric steroids was described.

Journal ArticleDOI
TL;DR: A new color reaction of [Ru(Hedta)(H2O)] with some compounds that contain groups C−SH or C=S has been found Alkanethiols, cysteine, thiourea and thiosulfate showed blue color.
Abstract: A new color reaction of [Ru(Hedta)(H2O)] with some compounds that contain groups C–SH or C=S has been found Alkanethiols, cysteine, thiourea and thiosulfate assume pink to reddish brown color, while benzenethiols show blue color It was suggested that the coloration is due to the anation of [Ru(Hedta)(H2O)] with sulfur-containing compounds

Patent
14 Nov 1978
TL;DR: In this paper, Antibiotic aculeacin DUPSILON Characteristics thereof are as follows: elementary analysis, C 5755, H 832, N 894, molecular weight by the Rast method, 1265; mp 159-162 degC; specific rotation [alpha] D =-465 deg(C 025, methanol); color reaction: positive to Pauly's reaction, etc, quasi positive to Molisch's reaction etc, negative to ninhydrin reaction, and soluble in lower alcohols, slightly soluble in ethyl acetate
Abstract: PURPOSE:Antibiotic aculeacin DUPSILON Characteristics thereof are as follows: elementary analysis, C 5755%, H 832%, N 894%, molecular weight by the Rast method, 1265; mp 159-162 degC; specific rotation [alpha] D =-465 deg(C 025, methanol); color reaction: positive to Pauly's reaction, etc, quasi positive to Molisch's reaction etc, negative to ninhydrin reaction, etc; soluble in lower alcohols, slightly soluble in ethyl acetate, hardly soluble in acetone, etc; white neutral substance; UV absorption spectrum shows a peak at 278nm; etc

Journal ArticleDOI
01 Nov 1978-Talanta
TL;DR: A sensitive and highly selective method for the spectrophotometric determination of microgram quantities of vanadium(V), which obeys Beer's law in the vanadium concentration range 0.6-12.5 mug/ml, has been applied to alloy steels.