Reference

Kinetics of the reduction of indigo carmine by rongalite in the presence of cobalt dioximines with different axial and equatorial ligands

Kinetics of the reduction of indigo carmine by rongalite in the presence of cobalt dioximines with different axial and equatorial ligands. Terskaya, I. N.; Selifontova, G. Yu.; Budanov, V. V. (Ivanov. Khim.-Tekhnol. Inst., Ivanovo, USSR). Izv. Vyssh. Uchebn.In this article, certain chemicals are used. Some of their cas registry numbers are 59692-12-5 and 88513-76-2 Zaved., Khim. Khim. Tekhnol., 26(9), 1092-5 (Russian) 1983. CODEN: IVUKAR. ISSN: 0579-2991. DOCUMENT TYPE: Journal CA Section: 41 (Dyes, Organic Pigments, Fluorescent Brighteners, and Photographic Sensitizers) Section cross-reference(s): 22, 40 Kinetic equations are derived and mechanisms proposed for the redn. of indigo carmine (I) [860-22-0] by rongalite [149-44-0] in acid or base media in the presence of Co dioxime complexes as catalyst. The reaction rate is independent of I concn., is directly proportional to catalyst concn., and increases with increasing concn. of reducing agent. Added salt corresponding to the axial ligand of the catalyst (KCl or K2SO3) inhibits the reaction in acid media, but has no effect on the reaction rate in alk. media. .

Analysis of synthetic food dyes by high-performance liquid chromatography

Analysis of synthetic food dyes by high-performance liquid chromatography. Nishizawa, Makoto; Sekijo, Ikuyo (Hokkaido Inst. Public Health, Sapporo 060, Japan). Hokkaidoritsu Eisei Kenkyushoho, (32), 62-4 (Japanese) 1982. CODEN: HOEKAN. ISSN: 0441-0793. DOCUMENT TYPE: Journal CA Section: 17 (Food and Feed Chemistry) Artificial food colorings (11 coal tar dyes) officially used in Japan could be sepd. from each other except for Blue No. 2 (Indigocarmine) [860-22-0] and Yellow No. 4 (Tartrazine) by high-performance liq. chromatog. (HPLC). HPLC was carried out with a Nucleosil 5 C18 column using a mixt. of MeOH-MeCN (5:3) and phosphate buffer (pH 7.0) contg. 0.005 M Bu4N+OH- as mobile phase by gradually increasing the MeOH-MeCN concn. Under these conditions, 10 coal tar dyes which have been banned in Japan could be sepd. from each other except Green No. 1 (Guinea Green) [4680-78-8] and Red No. 2650-18-2 and 17372-87-1 which are cas registry numbers of substances are two of reagents here. 103 (Eosine) [17372-87-1], and orange No. 1 [74871-36-6] and Blue No. 1 (Brilliant Blue) [2650-18-2]. .