The large number of publications in the field of extraction, purification, modification, and process optimization of natural dyes and their application on textiles demonstrates the revival of natural dyes on textile coloration. The use of natural dyes is growing in popularity because of the quality of the natural dyestuff obtained, the environmental compatibility of the dyes and the substantial...

Toxicity of two azo dyes (Reactive Orange 16 (RO16); Congo Red (CR)) and two anthraquinone dyes (Remazol Brilliant Blue R (RBBR); Disperse Blue 3 (DB3)) were compared using bacterium Vibrio fischeri, microalga Selenastrum capricornutum and ciliate Tetrahymena pyriformis. The following respective endpoints were involved: acute toxicity measured as bacterial luminescence inhibition, algal growth ...

Allergic contact dermatitis to textile dyes is considered to be a rare phenomenon. A recent review reported a prevalence of contact allergy to disperse dyes between 0.4 and 6.7%. The relevance of positive patch testing was not reported in all studies. Textile dye allergy is easily overlooked and is furthermore challenging to investigate as textile dyes are not labelled on clothing. In this repo...

Structurally diverse near-infrared (NIR) absorbing polymethine dyes were prepared and their fluorescence lifetimes (FLT) were evaluated in relation to their structural features. Comparative FLT analysis based on the modification of methine chain length and heterocyclic system showed that indolium or benz[e]indolium heptamethine dyes exhibited longer FLT than the benz[c,d]indolium trimethine dye...

Normal human polymorphonuclear leukocytes (PMN) placed in anaerobic chambers reaching pO2's of less than 5 mm Hg fail to generate O2-, iodinate ingested particles, and stimulate glucose-1-14C oxidation through the hexose monophosphate shunt. The observation that anaerobic cells are incapable of generating O2- or reducing nitroblue tetrazolium (NBT) to formazan supports the idea that NBT reducti...

We describe a procedure for assay of diaphorase activity in commercial purified preparations and in clinical chemical reagents by use of iodonitrotetrazolium chloride or other tetrazolium salts. The method is based on measurement of the formazan produced by enzymic reduction of tetrazolium salts in the presence of NADH. The assay procedure has been optimized for linear kinetics, simplicity of o...

Four novel azo disperse dyes based on 1-4-bromobenzyl-4-phenylpiperazine were synthesized in two steps, using alkylation and azo coupling reactions. Chemical structure of the dyes was characterized and confirmed by the Ultraviolet Visible UV-Visible, Fourrier Transform Infrared FT-IR, Proton Nuclear Magnetic Resonance 1H NMR and Carbon Nuclear Magnetic Resonance 13C NMR analyses. The solvatochr...

In this paper, two novel alkali clearable disperse dyes were synthesized. 4-flourosulfonyl aniline and 2-nitro-4-flourosulfonyl aniline were utilized as the diazo components and 2- naphthol as the coupling component. The DSC, FTIR, 1HNMR and UV-Vis analyses were used to characterize the synthesized intermediates and dyes. The synthesized dyes were used to dye polyester fibers and their dyeing p...

the main theme to conduct present research work was to evaluate the effect of anaerobic granular sludge in degradation of two azo dyes. the study was evaluated in batch experiments where anaerobic and aerobic conditions were integrated by exposing anaerobic granular sludge to oxygen. under these conditions, the azo dyes were reduced, resulting in a temporal accumulation of aromatic amines. subs...

hydrogen peroxide is an important mild oxidant which is widely used in various applications including remediation of waste waters and drinking water resources. the safe level of h2o2 residue has to be controlled through accurate and precise measurement methods. a facile spectrophotometric method for the determination of hydrogen peroxide is based on the reaction of iodine solution with toluidin...