Topic
Color reaction
About: Color reaction is a research topic. Over the lifetime, 1194 publications have been published within this topic receiving 19579 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, the specific coloration of the benzylamine type compounds in the ninhydrin color reaction is extended to other kinds of compounds, such as benzylaniline and p-dimethylaminobenzylamines.
Abstract: The specific coloration of the benzylamine type compounds in the ninhydrin color reaction is extended to other kinds of compounds. Alloxan resembles ninhydrin in its behaviour as reagent. The fact that the specific coloration reaction seems to be common to the benzylamine type compounds, is verified. However a few exceptions are observed as in the case of benzylaniline (17) and p-dimethylaminobenzylamine (18). The fact that the color change of these compounds in the usual paper chromatography is due to moisture in the air, is confirmed.
5 citations
TL;DR: Folin's colorimetric method for the determination of amino acids has been found applicable to the analysis of histamine phosphate injection, U. S. P.
Abstract: Folin's colorimetric method for the determination of amino acids has been found applicable to the analysis of histamine phosphate injection, U. S. P. A color is developed by treating histamine with 1,2-naphthoquinone-4-sodium sulfonate which obeys Beer's law within the range indicated. Optimum conditions for this color reaction and measurement have been defined.
5 citations
TL;DR: In this article, the relationship between layered water and coloration of some complexes between montmorillonite and benzidine or other similar compounds has been discussed, and it is shown that they may be divided into types according to the structures of organic compounds.
Abstract: The relationship between layered water and coloration of some complexes between montmorillonite and benzidine or other similar compounds has been discussed, and it is shown that they may be divided into types according to the structures of organic compounds. The shrinkage and swelling of the layer distance of the complex caused by its dehydration and hydration are observed. The coloration of the monofunctional-complex is not so remarkable and that of the bifunctional-complex is remarkable. In the case of monofunctional-complex or the bifunctional-complex with benzidine, the amino-or hydroxyl-radical fixes on one side of the silicate layer, and then, when it is saturated with water, the water molecules get into the silicate layer. On the other hand, in the bifunctional-complex with paramine, as the amino- or hydroxyl-radical fixes on both sides of the silicate layers, the water molecules no longer get into it.
5 citations
TL;DR: The colour reaction has been made specific, and has been applied to the colorimetric determination of methyl-thiouracil in urine.
Abstract: IN a recent communication1, I described a new colour reaction for the antithyroid drugs, 2-thiouracil and 4-methyl-2-thiouracil. This is based upon the yellow colour which is given when small concentrations of the drugs are treated with 2 : 6-dichloro-quinone-chloroimide at pH 8.0. Although some free amino-acids, purines and other urinary solutes give coloured products in the reaction, these latter are insoluble in chloroform, whereas within certain concentration limits the coloured products of the reaction with the drugs are readily extractable from the aqueous phase by this solvent. By this means the colour reaction has been made specific, and has been applied to the colorimetric determination of methyl-thiouracil in urine.
5 citations
TL;DR: Opto-chemical capillary clocks are presented that are based on the measurement of a colored segment in a microchannel (a capillary). Color is created by a chromogenic chemistry involving the oxidation of a (virtually colorless) leuco-dye.
Abstract: Opto-chemical capillary clocks are presented that are based on the measurement of a colored segment in a microchannel (a capillary). Color is created by a chromogenic chemistry involving the oxidation of a (virtually colorless) leuco-dye. Poly(ethylene glycol) (PEG) is used as a solvent, and indigo and thioindigo (in their reduced leuco forms) act as oxygen-sensitive dyes. The clock is started by removing one seal at the end of the capillary. A visible color change occurs as air diffuses into the microchannel due to an irreversible color reaction. The length of the colored segment is proportional to the time elapsed. PEGs of different average molar mass affect the diffusion rate of oxygen in the microchannel and thereby affect the rate of the migration of the color front. Both temperature and relative humidity exert a strong effect. Six types of such clocks are described that enable times to be determined in the range from 1 day to 6 months, possibly of even decades.
5 citations