Optical screening for presence of banned Sudan III and Sudan IV dyes in edible palm oils

A simple and rapid multiresidue method for the determination of nine banned synthetic dyes in various spices has been developed. Reversed phase HPLC coupled with mass spectrometry (tandem in time−ion trap mass analyser) was employed for the examination of crude acetonitrile extract acidified with acetic acid. The detection limits of Para Red, Sudan Orange G, Sudan I, Sudan II, Sudan III, Sudan IV, Sudan Red 7B and Rhodamine B were in the range of 0.02−0.1 mg/kg, the recoveries ranged from 75.7−92.3% with repeatability of 0.9−11.3%. Rather worse performance characteristics were obtained with Tropaeolin 000, obviously due to its more polar nature as compared to other dyes involved in this study. In spite of that, the developed method can be used for a reliable control of a wide range of dyes used for illegal colouring of various spices.

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The specific and nonspecific solvatochromic behavior of Sudan dyes in different solvents

Canadian Journal of Chemistry ◽

10.1139/cjc-2014-0489 ◽

2015 ◽

Vol 93 (6) ◽

pp. 639-647 ◽

Cited By ~ 3

Author(s):

M.S. Zakerhamidi ◽

S.M. Seyed Ahmadian ◽

R. Kian

Keyword(s):

Fluorescence Spectra ◽

Room Temperature ◽

Molecular Configuration ◽

Sudan Dyes ◽

Polar Solvents ◽

Sudan Black B ◽

Sudan Iv ◽

Sudan Iii ◽

Linear Solvation Energy ◽

Solute Interactions

Absorption and fluorescence spectra of some Sudan dyes (Sudan III, Sudan IV, and Sudan Black B) were recorded in various solvents in the range of 300–800 nm at room temperature. The solvatochromic behavior of these substances and their solvent–solute interactions were analyzed by means of the linear solvation energy relationship concept suggested by Kamlet and Taft. The obtained results express the effect of solvation on the tautomerism and molecular configuration (geometry) of Sudan dyes in solvent media. Furthermore, analysis of solvent–solute interactions suggests different forms of resonance structures of Sudan dyes in polar and low-polar solvents.

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Electrochemical reduction of azo dyes mimicking their biotransformation to more toxic products

Journal of Veterinary Research ◽

10.2478/jvetres-2019-0044 ◽

2019 ◽

Vol 63 (3) ◽

pp. 433-438 ◽

Cited By ~ 3

Author(s):

Konrad Pietruk ◽

Marta Piątkowska ◽

Małgorzata Olejnik

Keyword(s):

Azo Dyes ◽

Aromatic Amines ◽

Electrochemical Reactor ◽

Feed Additives ◽

Promising Tool ◽

Sudan I ◽

Food And Feed ◽

Transformation Mechanisms ◽

Sudan Iv ◽

Sudan Iii

Abstract Introduction Some azo dyes, including Sudans I–IV and Para Red, are genotoxic and may be biotransformed to cancerogenic aromatic amines. They are banned as food and feed additives, but their presence has been detected in food. Aromatic amines are also considered potentially toxic. Online EC–MS is a promising tool to study the transformation mechanisms of xenobiotics such as azo dyes. The aim of the study was to investigate emulation of how azo dyes are enzymatically transformed to amines with EC–MS. Material and Methods The reduction reactions of five azo dyes (Sudans I–IV and Para Red) were conducted using a glassy carbon working electrode and 0.1% formic acid in acetonitrile. Reduction results were compared with the literature and in silico to select preliminary candidates for metabolites. The LC-MS/MS method was used to confirm results obtained by electrochemical reactor. Results A limited number of pre-selected compounds were confirmed as azo dyes metabolites – aniline for Sudan I, aniline and 4-aminoazobenzene for Sudan III, o-toluidine for Sudan IV, and 4-nitroaniline for Para Red. No metabolites were found for Sudan II. Conclusions Electrochemistry–mass spectrometry was successfully applied to azo dyes. This approach may be used to mimic the metabolism of azo dyes, and therefore predict products of biotransformation.

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