Interaction of sulphone based reactive dyes with cationic surfactant: a spectroscopic and conductometric study

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Misbah Iram ◽  
Hamadia Sultana ◽  
Muhammad Usman ◽  
Bazgha Ahmad ◽  
Nadia Akram ◽  
...  
Keyword(s):  
Strong Interaction ◽  
Cetyltrimethylammonium Bromide ◽  
Hydrophobic Interactions ◽  
Reactive Dyes ◽  
Micellar System ◽  
Palisade Layer ◽  
Micellar Systems ◽  
Gibbs Energies ◽  
Electrostatic And Hydrophobic Interactions ◽  
Conductometric Study

Abstract Interaction of sulphone based reactive dyes, designated as dye-1 and dye-2, with cationic micellar system of cetyltrimethylammonium bromide (CTAB), has been investigated by spectroscopic and conductometeric measurements. Efficiency of the selected micellar systems is assessed by the values of binding constant (K b ), partition coefficient (K x ) and respective Gibbs energies. Critical micelle concentration (CMC) of surfactant, electrostatic and hydrophobic interactions as well as polarity of the medium plays significant role in this phenomenon. The negative values of Gibbs energies of binding (∆G b ) and partition (∆G p ) predicts the feasibility and spontaneity of respective processes. Similarly negative values of ∆G m and ∆H m and positive values of ∆S m , calculated from conductometeric data, further, revealed the exothermicity, spontaneity and, thus, stability of system. The results, herein, have disclosed the strong interaction between dye and surfactant molecules. The dye-2 has been observed to be solubilized to greater extent, as compared to dye 1, due to strong interaction ith hydrophiles of CTAB and accommodation of its molecules in palisade layer of micelle closer to the micelle/water interface.

scholarly journals Determination of critical micelle concentration of cetyltrimethylammonium bromide: Different procedures for analysis of experimental data

2016 ◽  
Vol 70 (4) ◽  
pp. 485-492 ◽  
Author(s):  
Jelena Goronja ◽  
Aleksandra Janosevic-Lezaic ◽  
Biljana Dimitrijevic ◽  
Andjelija Malenovic ◽  
Dragomir Stanisavljev ◽  
...  
Keyword(s):  
Critical Micelle Concentration ◽  
Cetyltrimethylammonium Bromide ◽  
Integration Method ◽  
Water Mixture ◽  
Micellar System ◽  
Sharp Transition ◽  
Water Conductivity ◽  
Micellar Systems ◽  
Significant Difference

Conductivity of two micellar systems was measured in order to determine critical micelle concentration (CMC) of cetyltrimethylammonium bromide (CTAB). Those systems were: CTin water and CTin binary mixture acetonitrile (ACN)-water. Conductivity (?)-concentration (c) data were treated by four different methods: conventional method, differential methods (first and second derivative) and method of integration (methods A-D, respectively). As CTin water micellar system shows a sharp transition between premicellar and postmicellar part of the ?/c curve, any of the applied methods gives reliable CMC values and there is no statistically significant difference between them. However, for CTin ACN-water mixture micellar system the integration method for CMC determination is recommended due to a weak curvature of ?/c plot.

scholarly journals Prospects for the use of mixed micellar structures as a template in synthesis of MCM-41-type silicas

2021 ◽  
pp. 79-89
Author(s):  
N.V. Roik ◽  
◽  
L.O. Belyakova ◽  
М.О. Dziazko
Keyword(s):  
Azo Dye ◽  
Cetyltrimethylammonium Bromide ◽  
Mixed Micelles ◽  
Hydrophobic Interactions ◽  
Sol Gel ◽  
Standard Free Energy ◽  
Reaction Medium ◽  
Total Pore Volume ◽  
Methyl Red ◽  
Sol Gel Synthesis

Formation of mixed micelles assisted by cetyltrimethylammonium bromide and methyl red was studied by means of conductometric and spectrophotometric methods. It follows from the analysis of conductometric dependences that the addition of azo dye leads to a decrease in critical micelle concentration of a long-chain quaternary ammonium salt. The respective thermodynamic parameters were calculated. The process of mixed micelles formation was stated to be spontaneous and the solubilization of azo dye by micelles of cetyltrimethylammonium bromide is profitable in terms of energy and accompanied by an increase in degrees of freedom of the system. Based on the data of spectrophotometric study of methyl red solutions in the presence of cetyltrimethylammonium bromide, the values of stability constant, partition coefficient and change in the standard free energy of methyl red distribution between aqueous and micellar medium were calculated. It was found that electrostatic and hydrophobic interactions arising between azo dye and cetyltrimethylammonium bromide molecules cause the orientation of methyl red from the shell towards the center of the micelles. It was shown that mixed micelles can be used as a template in sol-gel synthesis of mesoporous aminosilica of MSM-41 type. The results of low-temperature nitrogen adsorption-desorption and X-ray analysis revealed that the introduction of methyl red as a part of mixed micelles into the reaction medium of sol-gel synthesis causes substantial increase in specific surface area and total pore volume, noticeable reduction of pore diameter, thereby contributing to the formation of silica material with a pronounced long-range ordered mesoporous structure.

Surface Treatment of Wool to Achieve Hydrophilic Fibre and the Effect on Subsequent Dyeing and Protease Treatment

2012 ◽  
Vol 441 ◽  
pp. 249-254 ◽  
Author(s):  
Edward Smith ◽  
Jin Song Shen
Keyword(s):  
Enzyme Activity ◽  
Cetyltrimethylammonium Bromide ◽  
Treatment Process ◽  
Proteolytic Enzymes ◽  
Reactive Dyes ◽  
Fibre Surface ◽  
Enzyme Treatment ◽  
Lipid Layer ◽  
Alkaline Conditions ◽  
Protease Treatment

Wool was treated with cetyltrimethylammonium bromide (CTAB) under alkaline conditions to remove the lipid layer from the fibre surface. A reduction in lipid content of 88% could be achieved resulting in a very hydrophilic fibre. The efficiency of dyeing with reactive dyes was improved. When treated with proteolytic enzymes (protease) a loss of enzyme activity occurred due to residual CTAB on the fibre surface. Residual CTAB could be removed from the fibre using solvent or anionic surfactant in acid conditions ensuring enzyme activity. Hydrophilic wool could promote a more efficient proteolytic enzyme treatment process.

scholarly journals Interaction of caldesmon with phospholipids

1993 ◽  
Vol 291 (2) ◽  
pp. 403-408 ◽  
Author(s):  
E A Czuryło ◽  
J Zborowski ◽  
R Dabrowska
Keyword(s):  
Fluorescence Spectroscopy ◽  
Hydrophobic Interactions ◽  
Tryptophan Fluorescence ◽  
Terminal Part ◽  
Strong Binding ◽  
Terminal Fragment ◽  
Electrostatic And Hydrophobic Interactions ◽  
The Stability

The interaction of caldesmon with liposomes composed of various phospholipids has been examined by tryptophan fluorescence spectroscopy. The results indicate that caldesmon makes its strongest complex with phosphatidylserine (PS) vesicles (Kass. = 1.45 x 10(5) M-1). Both electrostatic and hydrophobic interactions contribute to the stability of this complex. The site for strong binding of PS seems to be located in the N-terminal part of the 34 kDa C-terminal fragment of caldesmon. Binding of PS at this site results in displacement of calmodulin from its complex with caldesmon.

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