scholarly journals STUDY OF PROTOLYTIC EQUILIBRIA IN SOLUTIONS OF HYDROXYANTHRAQUINONE DYES BY CHEMICAL CHROMATICITY METHOD

2017 ◽  
Vol 60 (3) ◽  
pp. 22 ◽  
Author(s):  
Alexandr N. Chebotarev ◽  
Denys V. Snigur ◽  
Kateryna V. Bevziuk
Keyword(s):  
Sulfo Group ◽  
Analytical Signal ◽  
Alizarin Red S ◽  
Molecular Forms ◽  
Acid Base ◽  
Alizarin Red ◽  
Protolytic Equilibria ◽  
Wide Range ◽  
Spectrophotometric Data ◽  
Alizarin Complexone

In this paper, the acid-base properties of hydroxyanthraquinone dyes-alizarin, alizarin red S and alizarin-complexone- were studied in aqueous solutions by chemical chromaticity and spectrophotometry methods. The advantages of chemical chromaticity method over UV-VIS spectrophotometry method were shown in the protolytic equilibria study in dyes solutions. The chemical chromaticity method, unlike spectrophotometry, can determine the deprotonation constant of sulfo group of alizarin red S. Using the chromaticity functions data it is possible to determine all ionization constant of these hydroxyanthraquinone dyes. The overlay of tautomeric equilibria on alizarin-complexone ionization process does not interfere for pK determination of their functional groups by the chemical chromaticity method. A quantitative color description of objects of different nature by calculating their color coordinates by spectrophotometric data allows distinguishing spectrally similar substances and obtaining new data on them. Using the values of chromaticity functions of ion-molecule forms of the hydroxyanthraquinone dyes as an analytical signal allows to get a complete picture of the existing acid-base equilibria in a wide range of medium acidity. A probable acid-base equilibria schemes were theoretically determined for alizarin, alizarin red S and alizarin-complexone using CNDO calculations. The diagrams of the ion-molecular forms distribution of hydroxyanthraquinone were built.For citation:Chebotarev A.N., Snigur D.V., Bevziuk K.V. Study of protolytic equilibria in solutions of hydroxyanthraquinone dyes by chemical chromaticity method. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 3. P. 22-28. 

scholarly journals Adsorption of Malachite Green and Alizarin Red S Dyes Using Fe-BTC Metal Organic Framework as Adsorbent

2021 ◽  
Vol 22 (2) ◽  
pp. 788
Author(s):  
Giulia Rossella Delpiano ◽  
Davide Tocco ◽  
Luca Medda ◽  
Edmond Magner ◽  
Andrea Salis
Keyword(s):  
Malachite Green ◽  
Organic Dyes ◽  
Metal Organic Framework ◽  
Alizarin Red S ◽  
Alizarin Red ◽  
Industrial Sectors ◽  
Vis Spectroscopy ◽  
Wide Range ◽  
Metal Organic ◽  
Pseudo Second Order

Synthetic organic dyes are widely used in various industrial sectors but are also among the most harmful water pollutants. In the last decade, significant efforts have been made to develop improved materials for the removal of dyes from water, in particular, on nanostructured adsorbent materials. Metal organic frameworks (MOFs) are an attractive class of hybrid nanostructured materials with an extremely wide range of applications including adsorption. In the present work, an iron-based Fe-BTC MOF, prepared according to a rapid, aqueous-based procedure, was used as an adsorbent for the removal of alizarin red S (ARS) and malachite green (MG) dyes from water. The synthesized material was characterized in detail, while the adsorption of the dyes was monitored by UV-Vis spectroscopy. An optimal adsorption pH of 4, likely due to the establishment of favorable interactions between dyes and Fe-BTC, was found. At this pH and at a temperature of 298 K, adsorption equilibrium was reached in less than 30 min following a pseudo-second order kinetics, with k″ of 4.29 × 10−3 and 3.98 × 10−2 g∙mg−1 min−1 for ARS and MG, respectively. The adsorption isotherm followed the Langmuir model with maximal adsorption capacities of 80 mg∙g−1 (ARS) and 177 mg∙g−1 (MG), and KL of 9.30·103 L∙mg−1 (ARS) and 51.56·103 L∙mg−1 (MG).

scholarly journals Globular adiponectin inhibits osteoblastic differentiation of vascular smooth muscle cells through the PI3K/AKT and Wnt/β-catenin pathway

2021 ◽  
Author(s):  
Yun Zhou ◽  
Li-Long Wei ◽  
Rui-Ping Zhang ◽  
Cheng-Wu Han ◽  
Yongtong Cao
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Smooth Muscle Cells ◽  
Muscle Cells ◽  
Osteoblastic Differentiation ◽  
Alizarin Red S ◽  
Regulation Mechanism ◽  
Alizarin Red ◽  
Globular Adiponectin

AbstractLipid metabolism is closely related to the improvement of vascular calcification (VC) in chronic kidney disease (CKD). Globular adiponectin (gAd) has been reported to be involved in the development of VC in CKD, but the detailed regulatory role remains unclear. The present study is aimed to investigate the biological function and the underlying regulation mechanism of gAd in the process of VC during CKD. Vascular smooth muscle cells (VSMCs) calcification was determined by Alizarin Red S staining. Protein signaling related with VC was tested by western blotting. The expression and intracellular localization of runt-related transcription factor 2 (Runx2) was detected by immunofluorescence and uraemic rat with VC was established by a two-step nephrectomy. Combined with the results of Alizarin Red S staining, we discovered that β-glycerophosphate (β-Gp)-induced the osteoblastic differentiation of VSMCs was significantly reversed by gAd treatment. Along with the VSMCs calcification and the increase of Runx2 in β-Gp-exposed VSMCs, the activities of protein kinase B (AKT) and Wnt/β-catenin pathway were enhanced, but that were counteracted by the exposure of gAd in rat and human VSMCs. After administration with agonists of the Wnt (SKL2001) and AKT (SC79), there appeared more osteoblastic differentiation and higher expression of Runx2 in gAd-treated VSMCs, but showing lower impact in the presence of SC79 than that in the presence of SKL2001. In the in vivo experiments, intravenous injection of gAd also significantly inhibited VC and Runx2 level in uraemic rat in a dose-dependent manner, possibly through regulating Wnt/β-catenin pathway. This study demonstrates that gAd ameliorates osteoblastic differentiation of VSMCs possibly by blocking PI3K/AKT and Wnt/β-catenin signaling transduction. The findings provide an important foundation for gAd in treating VC in kidney diseases.

scholarly journals Lewis acid / Base-free Strategy for the Synthesis of 2-Arylthio and Selenyl Benzothiazole / Thiazole and Imidazole

2021 ◽  
Vol 27 (1) ◽  
pp. 17-23
Author(s):  
Guniganti Balakishan ◽  
Gullapalli Kumaraswamy ◽  
Vykunthapu Narayanarao ◽  
Pagilla Shankaraiah
Keyword(s):  
Lewis Acid ◽  
Bond Formation ◽  
Acid Base ◽  
Mechanistic Pathway ◽  
Wide Range ◽  
Acid And Base ◽  
Lewis Acid And Base ◽  
Sulfur Bond

Abstract A Cu(II)-catalyzed Csp2-Se and Csp2-Sulfur bond formation was achieved with moderate to good yields without the aid of Lewis acid and base. The reaction is compatible with a wide range of heterocycles such as benzothiazole, thiazole, and imidazole. Also, this typical protocol is found to be active in thio-selenation via S-H activation. Additionally, we proposed a plausible mechanistic pathway involving Cu(III) putative intermediate.

Cellulose Supported Thorium-Alizarin Red S Reagent for Fluoride Ion Determination

1958 ◽  
Vol 30 (9) ◽  
pp. 1485-1489 ◽  
Author(s):  
S. K. Yasuda ◽  
J. L. Lambert
Keyword(s):  
Alizarin Red S ◽  
Fluoride Ion ◽  
Alizarin Red

Spectrophotometric study of the complex of lanthanum and alizarin Red S

Talanta ◽  
1961 ◽  
Vol 8 (7) ◽  
pp. 552-556 ◽  
Author(s):  
Toshi Kawashima ◽  
Haruno Ogawa ◽  
Hiroshi Hamaguchi
Keyword(s):  
Spectrophotometric Study ◽  
Alizarin Red S ◽  
Alizarin Red
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