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Exploratory study on sequestration of some essential metals by indigo carmine food dye
Zanoni, Thalita Boldrin;Cardoso, Arnaldo Alves;Zanoni, Maria Valnice Boldrin;Ferreira, Antonio Aparecido Pupim;
Brazilian Journal of Pharmaceutical Sciences , 2010, DOI: 10.1590/S1984-82502010000400014
Abstract: indigo carmine forms a stable complex with different ions, and the stability constant of the complexes were evaluated as log k equal to 5.75; 5.00; 4.89 and 3.89 for complexes with cu(ii), ni(ii), co(ii) and zn(ii) ions, respectively, in 0.1 mol l-1 carbonate buffer solution at ph 10. the interaction between cu(ii) ions and indigo carmine (ic) in alkaline medium resulted in the formation of the cu2(ic) complex, measured by the spectrophotometric method, with a stoichiometric ratio between indigo carmine and metal ions of 2:1 (metal-ligand). the reported method has also been successfully tested for determination of copper in pharmaceutical compounds based on copper-gluconate without pre-treatment.
Effect of silica sources in nanoporous silica synthesis on releasing behavior of indigo carmine
Chanatip Samart,Chatchawan Sookman
Songklanakarin Journal of Science and Technology , 2009,
Abstract: Nanoporous silica was applied in controlled releasing experiments. Different physical properties of the nanoporous silica, related to variations of the silica sources, affected the releasing behaviour. Two different silica precursors in nanoporous silica synthesis were investigated, tetraethoxysilane and sodium silicate. The nanoporous silica, which was obtained by tetraethoxysilane, gave the highest surface area (800 m2/g) and pore volume (1.2 cc/g). On the other hand, the nanoporous silica obtaining from sodium silicate showed the largest pore size (9 nm). The nanoporous silica with larger pore volume can load a higher amount of indigo carmine, which resulted in a fast release due to the large driving force between the silicaparticle and media solution. However, the releasing rate was not only affected by the pore volume, but also by the interactionbetween the silanol groups on the silica surface and molecules of indigo carmine.
Photocatalytic Degradation of Indigo Carmine Dye Using Calcium Oxide  [PDF]
Kirana Devarahosahalli Veeranna,Madhu Theeta Lakshamaiah,Ramesh Thimmasandra Narayan
International Journal of Photochemistry , 2014, DOI: 10.1155/2014/530570
Abstract: Calcium oxide was used as photocatalyst for the degradation of indigo carmine dye solution in the visible, long UV, and short UV radiation. We have investigated the effectiveness of degradation of indigo carmine dye solution at pH 9 and 12 using calcium oxide with the particle size of 30–36?nm by varying the concentration, dose of adsorbent, and duration. It has been found that the degradation of indigo carmine dye is effective at pH = 9, when 0.12?g of calcium oxide was used. The nature of interaction between calcium oxide and indigo carmine dye was discussed. 1. Introduction The water bodies are continuously polluted due to the unscientific methods adopted by the chemical, textile, paper, and pulp industries, and so forth, during the discharge of toxic and hazardous chemicals [1–5]. Complexity of the dye molecules does not favour the natural process of degradation and also during certain instances incomplete degradation or transformation may generate carcinogenic byproducts [6–9]. Therefore, physical, chemical, and biological methods have been developed for the treatment of dye effluents from industries [10]. Precipitation, coagulation, floatation, and oxidizing agents have been used for the treatment of different types of dyes. Major disadvantages of chemical methods are that they require expensive chemicals and the products generated after dye treatment are also polluting in nature [11, 12]. Biological methods to degrade dyes include enzymes and microorganisms and are found to be effective but the difficulty is to scale up the process [13]. Membrane-filtration processes, electrodialysis, and adsorption involve physical processes which are cheaper compared to biological methods but the maintenance of membranes is expensive [14–16]. Electrochemical process, electrokinetic coagulation, irradiation with light, and photochemical oxidation have been employed for the removal of dye effluents [17]. Major limitations of the above methods are the operating cost, generation of byproducts, and the process of regeneration of the starting compounds which are difficult or tedious [10]. Therefore, degradation of dyes into its smaller fragments of less toxic organic compounds is one of the major challenges faced by scientists, technologists, and researchers across the world. Development of catalysts which can interact with sunlight and degrade the toxic dyes into its low molecular weight colourless and nontoxic fragments which can be discharged into the water bodies without affecting their physicochemical properties is the major objective. Photocatalytic degradation
Degradation of Indigo Carmine Using Advanced Oxidation Processes: Synergy Effects and Toxicological Study  [PDF]
Elba Ortiz, Violeta Gómez-Chávez, Carlos M. Cortés-Romero, Hugo Solís, Rubén Ruiz-Ramos, Sandra Loera-Serna
Journal of Environmental Protection (JEP) , 2016, DOI: 10.4236/jep.2016.712137
The physicochemical degradation of Indigo Carmine (IC) dye in aqueous solution was performed using single and combined Advanced Oxidation Processes (AOP’s). Photocatalysis (TiO2-UV), Ozonation (O3) and Sonolysis (SN) were tested either in a standalone methodology or by combination of two simultaneous AOP’s. The dye conversion was followed by both measurements: 1) color removal determined by UV-VIS spectrometry and 2) organic and inorganic load determined by the chemical oxygen demand (COD). A complete and quick color disappearance of model water waste has been obtained by using combination of non-irradiated AOP’s, namely, O3/SN, which contrasts to the combination of irradiated photocatalysis with O3 or sonolysis. Color removal with simultaneous TiO2-UV/SN reached 77% while TiO2-UV/O3 reached 96% at similar reaction time. On the other hand, the standalone O3 yielded the highest color removal (94.4%) in 32 minutes whereas SN reached only 39.2% in 4 hours. The standalone light irradiated TiO2-UV reached 93.3% color re-moval in one hour of reaction time. These results indicated that non-irradiated (SN and O3) enhance synergistic effects that provoke structural changes in dye molecule without reaching total degradation. This is evidenced from FTIR of residuals from reaction mixture in which it has been observed the presence of organic molecules such as aromatics, sulfonic and amines refractory compounds that are mechanisti-cally possible to be found during IC degradation. Also, toxicity tests (MicroTox
Laccase isozymes of Pleurotus sajor-caju culture on husk and bran of black sticky rice and their potential on indigo carmine decolourisation
R Sarnthima, S Khammuang
African Journal of Biotechnology , 2008,
Abstract: Extracellular laccases of Pleurotus sajor-caju grown on solid state medium consisted of husk and bran of black sticky rice, were partially purified by DEAE–cellulose chromatography. These laccases could be separated into three groups: unboundLac and bound fractions (pool1Lac and pool2Lac). The optimum pH of these laccases was studied using ABTS as substrate. It was found that the pH optimum for unboundLac fell in the range of 3–5 and 3–4 for pool1Lac and pool2Lac. The indigo carmine decolourisation capacity was compared between unboundLac and pool2Lac. It was found that the optimal pH for indigo carmine decolourisation were 5 and 3 for unboundLac and pool2Lac, respectively. In the range of various dye concentrations tested, it was found that indigo carmine at 10 ìM with the enzyme activity of 0.01 U, gave the best dye decolourisation with 40.47% within 120 min for unboundLac and with 18.61% within 150 min for pool2Lac. High amount of enzyme used of these laccases might improve decolourisation ability.
Sm FeTaO Photocatalyst for Degradation of Indigo Carmine Dye under Solar Light Irradiation
Leticia M. Torres-Martínez,Miguel A. Ruiz-Gómez,M. Z. Figueroa-Torres,Isaías Juárez-Ramírez,Edgar Moctezuma
International Journal of Photoenergy , 2012, DOI: 10.1155/2012/939608
Abstract: This paper is focused to study Sm2FeTaO7 pyrochlore-type compound as solar photocatalyst for the degradation of indigo carmine dye in aqueous solution. Sm2FeTaO7 was synthesized by using conventional solid state reaction and sol-gel method. X-ray diffraction results indicated that Sm2FeTaO7 exhibit a monoclinic crystal structure. By scanning electron microscopy analysis, it was observed that sol-gel material presents particle size of around 150 nm. The specific surface area and energy bandgap values were 12 m2 g−1 and 2.0 eV, respectively. The photocatalytic results showed that indigo carmine molecule can be degraded under solar light irradiation using the synthesized materials, sol-gel photocatalyst was 8 times more active than solid state. On the other hand, when Sm2FeTaO7 was impregnated with CuO as cocatalyst the photocatalytic activity was increased because CuO acts as electron trap decreasing electron-hole pair recombination rates.
Titrimetric and spectrophotometric assay of felodipine in tablets using bromate–bromide, Methyl Orange and Indigo Carmine reagents
Journal of the Serbian Chemical Society , 2005,
Abstract: Three new methods based on titrimetric and spectrophotometric techniques are described for the determination of felodipine (FLD) in the bulk drug and in tablets using a bromate–bromide mixture and two dyes, Methyl Orange and Indigo Carmine. In the titrimetric method (method A), the drug solution was treated with a measured excess of the bromate–bromide mixture in acid medium, and after the reaction was judged to be complete, the unreacted bromine was determined iodometrically. The two spectrophotometricmethods are based on the bromination of the drug with a known excess of the bromate–bromide mixture under acidic conditions followed by the estimation of the surplus bromine by reaction with either Methyl Orange (Method B) or Indigo Carmine (Method C), and measuring the absorbance at 520 nm or 610 nm, respectively. In all the methods, the amount of reacted bromine corresponds to the drug content. The titrimetric procedure is applicable for between 6–15 mg and the reaction stoichiometry was found to be 1:1 (drug: BrO3-). The systems obey Beer’s law between 0.12 – 0.87 mgml-1 and 0.5 – 6.0 mgml-1 formethods B and C, respectively. The limits of detection and quantification are reported for both the spectrophotometricmethods. The methods could usefully be applied to routine quality control of pharmaceutical formulations containing FLD. Statistical comparison of the results with the reference method shows excellent agreement and indicates no significant difference in accuracy and precision.
Titrimetric and spectrophotometric determination of doxycycline hyclate using bromate-bromide, methyl orange and indigo carmine  [PDF]
Pavagada Jagannathamurthy Ramesh,Kanakapura Basavaiah,Mysore Ranganath Divya,Nagaraju Rajendraprasad
Chemical Industry and Chemical Engineering Quarterly , 2010,
Abstract: One titrimetric and two indirect spectrophotometric methods are described for the determination of doxycycline hyclate (DCH) in bulk drug and in its formulations. The methods use bromate-bromide, methyl orange and indigo carmine as reagents. In titrimetry (method A), DCH is treated with a known excess of bromate- -bromide mixture in acid medium and the residual bromine is back titrated iodometrically after the reaction between DCH and in situ bromine is ensured to be complete. In spectrophotometric methods, the excess of bromine is estimated by treating with a fixed amount of either methyl orange (method B) or indigo carmine (method C) and measuring the change in absorbance either at 520 or 610 nm. Titrimetric method is applicable over 1-8 mg range and the calculations are based on a 1:2 (DCH:bromate) stoichiometric ratio. In spectrophotometry, the calibration graphs were found to be linear over 0.25-1.25 and 1.0-5.0 μg mL-1 for method B and C, respectively, with corresponding molar absorptivity values of 2.62×105 and 6.97×104 L mol-1 cm-1. The accuracy and precision of the assays were determined by computing the intra-day and inter-day variations at three different levels of DCH.
Plasma induced degradation of Indigo Carmine by bipolar pulsed dielectric barrier discharge(DBD) in the water-air mixture
ZHANG Ruo-bing,WU Yan,LI Guo-feng,WANG Ning-hui,LI Jie,
ZHANG Ruo-bing
,WU Yan,LI Guo-feng,WANG Ning-hui,LI Jie

环境科学学报(英文版) , 2004,
Abstract: Degradation of the Indigo Carmine(IC) by the bipolar pulsed DBD in water-air mixture was studied. Effects of various parameters such as gas flow rate, solution conductivity, pulse repetitive rate and ect., on color removal efficiency of dying wastewater were investigated. Concentrations of gas phase O 3 and aqueous phase H 2O 2 under various conditions were measured. Experimental results showed that air bubbling facilitates the breakdown of water and promotes generation of chemically active species. Color removal efficiency of IC solution can be greatly improved by the air aeration under various solution conductivities. Decolorization efficiency increases with the increase of the gas flow rate, and decreases with the increase of the initial solution conductivity. A higher pulse repetitive rate and a larger pulse capacitor C\-p are favorable for the decolorization process. Ozone and hydrogen peroxide formed decreases with the increase of initial solution conductivity. In addition, preliminary analysis of the decolorization mechanisms is given.
Ru/AC Catalyzed Ozonation of Recalcitrant Organic Compounds

WANG Jian-bing,HOU Shao-pei,ZHOU Yun-rui,ZHU Wan-peng,HE Xu-wen,

环境科学 , 2009,
Abstract: Ozonation and Ru/AC catalyzed ozonation of dimethyl phthalate(DMP),phenols and disinfection by-products precursors were studied.It shows that Ru/AC catalyst can obviously enhance the mineralization of organic compounds.In the degradation of DMP,TOC removal was 28.84% by ozonation alone while it was 66.13% by catalytic ozonation.In the oxidation of 23 kinds of phenols,TOC removals were 9.57%-56.08% by ozonation alone while they were 41.81%-82.32% by catalytic ozonation.Compared to ozonation alone,Ru/AC catal...
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