Correlation of micellar aggregation – complexation regimes to discern stability of micellar structure and nano-encapsulation

2019 ◽  
Vol 547 ◽  
pp. 234-244 ◽  
Author(s):  
Leggins Abraham ◽  
Tiju Thomas ◽  
Moorthi Pichumani
Keyword(s):  
Micellar Structure

Exploring sensitivity of the extensional flow to wormlike micellar structure

2018 ◽  
Vol 252 ◽  
pp. 48-56 ◽  
Author(s):  
Rose Omidvar ◽  
Alireza Dalili ◽  
Ali Mir ◽  
Hadi Mohammadigoushki
Keyword(s):  
Extensional Flow ◽  
Micellar Structure

scholarly journals The Additive Influence of Propane-1,2-Diol on SDS Micellar Structure and Properties

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3773
Author(s):  
Martina Gudelj ◽  
Paola Šurina ◽  
Lucija Jurko ◽  
Ante Prkić ◽  
Perica Bošković
Keyword(s):  
Mixed Solvents ◽  
Sodium Dodecyl ◽  
Shielding Effect ◽  
Bulk Solution ◽  
Structure And Properties ◽  
Micellar Structure ◽  
Related Substances ◽  
Micellar Systems ◽  
Small Change ◽  
Additive Influence

Micellar systems are colloids with significant properties for pharmaceutical and food applications. They can be used to formulate thermodynamically stable mixtures to solubilize hydrophobic food-related substances. Furthermore, micellar formation is a complex process in which a variety of intermolecular interactions determine the course of formation and most important are the hydrophobic and hydrophilic interactions between surfactant–solvent and solvent–solvent. Glycols are organic compounds that belong to the group of alcohols. Among them, propane-1,2-diol (PG) is a substance commonly used as a food additive or ingredient in many cosmetic and hygiene products. The nature of the additive influences the micellar structure and properties of sodium dodecyl sulfate (SDS). When increasing the mass fraction of propane-1,2-diol in binary mixtures, the c.m.c. values decrease because propane-1,2-diol is a polar solvent, which gives it the ability to form hydrogen bonds, decreasing the cohesivity of water and reducing the dielectric constant of the aqueous phase. The values of ΔGm0 are negative in all mixed solvents according to the reduction in solvophobic interactions and increase in electrostatic interaction. With the rising concentration of cosolvent, the equilibrium between cosolvent in bulk solution and in the formed micelles is on the side of micelles, leading to the formation of micelles at a lower concentration with a small change in micellar size. According to the 1H NMR, with the addition of propylene glycol, there is a slight shift of SDS peaks towards lower ppm regions in comparison to the D2O peak. The shift is more evident with the increase in the amount of added propane-1,2-diol in comparison to the NMR spectra of pure SDS. Addition of propane-1,2-diol causes the upfield shift of the protons associated with hydrophilic groups, causing the shielding effect. This signifies that the alcohol is linked with the polar head groups of SDS due to its proximity to the SDS molecules.

scholarly journals Structure and Location of Protein Sites Binding Self-Associated Congo Red Molecules with Intercalated Drugs as Compact Ligands—Theoretical Studies

Biomolecules ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 501
Author(s):  
Ptak-Kaczor Magdalena ◽  
Kwiecińska Klaudia ◽  
Korchowiec Jacek ◽  
Chłopaś Katarzyna ◽  
Banach Mateusz ◽  
...  
Keyword(s):  
Organic Compounds ◽  
Light Chain ◽  
Congo Red ◽  
Theoretical Studies ◽  
Mathematical Tool ◽  
Supramolecular Systems ◽  
Micellar Structure ◽  
Protein Molecules ◽  
Toxic Drugs ◽  
Independent Property

In the search for new carriers capable of transporting toxic drugs to a target, particular attention has been devoted to supramolecular systems with a ribbon-like micellar structure of which Congo red is an example. A special promise of the possible use of such systems for directing drugs to a target emerges from their particular affinity to immune complexes and as an independent property, binding many organic compounds including drugs by intercalation. Serum albumin also appeared able to bind micellar particles of such systems. It may protect them against dilution in transport. The mathematical tool, which relies on analysis of the distribution of polarity and hydrophobicity in protein molecules (fuzzy oil drop model), has been used to find the location of binding area in albumin as well as anchorage site for Congo red in heated IgG light chain used as a model presenting immunoglobulin-like structures. Results confirm the suggested formerly binding site of Congo red in V domain of IgG light chain and indicated the cleft between pseudo-symmetric domains of albumin as the area of attachment for the dye.

Studies of the Conditions Affecting the Vulcanization of Rubber. V. The Effect of Accelerators on the Heat of Vulcanization

1931 ◽  
Vol 4 (2) ◽  
pp. 190-190
Author(s):  
Y. Toyabe
Keyword(s):  
Total Sulfur ◽  
Micellar Structure ◽  
Rubber Compounds ◽  
Chemical Combination ◽  
Differential Thermocouple ◽  
The Times

Abstract The heat of vulcanization of rubber compounds containing various quantities of sulfur and several organic vulcanization accelerators were traced by means of a differential thermocouple during the vulcanization. The profiles of the heating curves were similar to those obtained in the case of unaccelerated compounds, but the temperature maxima appeared sooner with accelerated than with unaccelerated compounds. The vulcanizates corresponding to the temperature-maxima were analyzed chemically by ordinary methods and the ratios of the free to total sulfur were calculated. They vary a little from 50 per cent, and show that the extent of sulfur combination is not much different from that with unaccelerated compounds. The accelerators tested were hexamethylenetetramine, aldehyde-ammonia diphenylguanidine, di-o-tolylguanidine, p-nitrosodimethylaniline, thiocarbanilide, “Vulkacit P”, “Vulkacit PX”, “Vulkacit M”, and tetramethylthiuramdisulfide The results of the experiments show that these accelerators promote the disaggregation of the micellar structure of rubber (as shown in reports II and III 0. this work) before chemical combination of rubber and sulfur occurs. By thus making the single micelle of rubber smaller, they increase the number of chemical units of rubber coming into reaction with sulfur; i. e., the probability of combination of rubber and sulfur becomes greater. The times for the temperature maxima to appear in the experiments above, which are shortened by accelerators, show that this theory holds good, when it is considered that the temperature maxima correspond to the disaggregation maxima of the rubber hydrocarbon under consideration.

The Chromatography of Rubber Solutions

1939 ◽  
Vol 12 (4) ◽  
pp. 762-773 ◽  
Author(s):  
Giampietro Cajelli
Keyword(s):  
Elastic Properties ◽  
Potassium Hydroxide ◽  
The Other ◽  
Precipitation Method ◽  
Insoluble Residue ◽  
Fractional Precipitation ◽  
Micellar Structure ◽  
X Ray ◽  
Colored Product ◽  
Considerable Doubt

Abstract In the opinion of Pummerer, there is considerable doubt about the homogeneity of the fractions obtained by fractional precipitation of rubber from dilute benzene solutions, both with respect to the size of the molecules and to the state of aggregation. Based on the results of x-ray measurements of fibrous substances, to which type stretched rubber belongs, Meyer and Mark have advanced the hypothesis of the existence of chains of primary valences and of a micellar structure. PURIFICATION OF RUBBER There are four important and at the same time essentially different ways of carrying out the difficult process of purifying rubber. According to Harries, acetone extraction gives a colored product and leads to profound changes in the elastic properties. Staudinger adopted the method described by Wildmann in 1911, which involves the use of a mixture of acetone and chloroform. On the other hand, Pummerer and Koch used the method of fractional precipitation; the rubber after severe mastication was extracted with acetone, was dissolved in benzene, the liquid was allowed to stand for several weeks, the solution was decanted from the insoluble residue and was fractionally precipitated by alcohol and acetone. More recently this same method has been perfected by Pummerer and Meidel, and by this means a fraction of crystallized rubber was isolated from the mother liquors of the fractional precipitation. Finally Pummerer and Koch have purified rubber by treatment with an alkali, combining the precipitation method with the use of a solution of potassium hydroxide in methanol. Later this method was modified by Pummerer and Pahl. The use of latex in place of crude rubber is the most important development in obtaining a satisfactory product. De Vries and Beumée-Nieuwland have described in detail some results obtained with fresh latex. The total-rubber obtained by the methods just described contains, according to the quality and the age of the sample of latex, from 0.1 to 0.4 per cent of nitrogen which cannot be removed by washing, even when this is exhaustive.

Sign in / Sign up

Export Citation Format

Share Document