Effect of carbohydrate based polymers on worm-like micelles of cetyltrimethylammonium p-toluenesulfonate in aqueous media: Detail physicochemical and antimicrobial properties survey

Investigation of the vesicle-to-micelle transition of 11-amino undecanoic acid derived sulphonamide and a comprehensive study of its interaction with protein

In the present manuscript, an amphiphile sulphonamide based surfactant benzenesulphonyl-11-amino sodium undecanoate (BASU) is designed and synthesized. The surface activity of the amphiphile in the solutions is studied at neutral pH so that the resulting amphiphile self-organizes and transfers from large unilamellar vesicles to small micelles from dilute to concentrated solutions. During the aggregate transitions, the common surfactants tend to form the small aggregate at low concentrations; but BASU shows the large vesicle structure at low concentration of ~3 mM and converts into the small micelle at ~9 mM. Therefore, different techniques have been used, such as, tensiometry, conductometry, fluorimetry and DLS and some microscopic characterization, e.g., confocal fluorescence microscopy to reveal the aggregate assembly and transition mechanism. The isothermal titration calorimetry is used for quantitative measurement of thermodynamic properties of self-assembly formation and the process is found spontaneous and entropically favorable. The permeability of the vesicle membrane bilayer is explored by a kinetic study. Effects of salt and cholesterol on the aggregate of respective amphiphile are also investigated. The interaction of surfactant with both human and bovine serum albumin is analyzed through UV-visible and fluorescence techniques to draw a comparative study. Antibacterial activity is tested by both spectral and zone inhibition methods and its application for mixed amphiphiles (e.g., BASU/CTAB) is found. Therefore, according to the ability of formation of unilamellar vesicles (ULV) and its stability, permeability and antibacterial activity, the amphiphile can have potential applications in the medicinal field.

Interactions between Ionic Cellulose Derivatives Recycled from Textile Wastes and Surfactants: Interfacial, Aggregation and Wettability Studies

Interactions between polymers (P) and surfactants (S) in aqueous solution lead to interfacial and aggregation phenomena that are not only of great interest in physical chemistry but also important for many industrial applications, such as the development of detergents and fabric softeners. Here, we synthesized two ionic derivatives-sodium carboxymethylcellulose (NaCMC) and quaternized cellulose (QC)-from cellulose recycled from textile wastes and then explored the interactions of these polymers with assorted surfactants-cationic (CTAB, gemini), anionic (SDS, SDBS) and nonionic (TX-100)-commonly used in the textile industry. We obtained surface tension curves of the P/S mixtures by fixing the polymer concentration and then increasing the surfactant concentration. In mixtures where polymer and surfactant are oppositely charged (P^-/S⁺ and P⁺/S^-), a strong association is observed, and from the surface tension curves, we determined the critical aggregation concentration (cac) and critical micelle concentration in the presence of polymer (cmc^p). For mixtures of similar charge (P⁺/S⁺ and P^-/S^-), virtually no interactions are observed, with the notable exception of the QC/CTAB system, which is much more surface active than the neat CTAB. We further investigated the effect of oppositely charged P/S mixtures on hydrophilicity by measuring the contact angles of aqueous droplets on a hydrophobic textile substrate. Significantly, both P^-/S⁺ and P⁺/S^- systems greatly enhance the hydrophilicity of the substrate at much lower surfactant concentrations than the surfactant alone (in particular in the QC/SDBS and QC/SDS systems).

Mimicking the Natural World with Nanoarchitectonics for Self-Assembled Superstructures

Scientists are often inspired by nature, where naturally occurring morphologies, such as those that resemble animals and plants, can be created in the lab. In this review, we have provided an overview on complex superstructures of animals, plants and some similar shapes from the natural world. We begin this review with a discussion about the formation of various animal-like shapes from small organic molecules and polymers, and then move onto plants and other selected shapes. Literature surveys reveal that most of the polymers studied tend to form micellar structures, with some exceptions. Nevertheless, small organic molecules tend to form not only micellar structures but also other animal shapes such as worms and caterpillars. These superstructures tend to have high surface areas and variable surface morphology, making them very useful material for applications in various field such as catalysis, solar cells, and biomedicine, amongst others.

A detailed assessment on the interaction of sodium alginate with a surface-active ionic liquid and a conventional surfactant: a multitechnique approach

Investigation has been made on the interaction of a biodegradable anionic polyelectrolyte, sodium alginate with two oppositely charged cationic surfactants, 1-hexadecyl-3-methyl imidazolium chloride and 1-hexadecyl triphenylphosphonium bromide, former is a...

Impact of the bulk aggregation on the adsorption of oppositely charged polyelectrolyte-surfactant mixtures onto solid surfaces

The understanding of the deposition of oppositely charged polyelectrolytes-surfactant mixtures onto solid surfaces presents a high interest in current days due to the recognized impact of the obtained layers on different industrial sectors and the performance of several consumer products (e.g. formulations of shampoos and hair conditioners). This results from the broad range of structures and properties that can present the mixed layers, which in most of the cases mirror the association process occurring between the polyelectrolyte chains and the oppositely charged surfactants in the bulk. Therefore, the understanding of the adsorption processes and characteristics of the adsorbed layers can be only attained from a careful examination of the self-assembly processes occurring in the solution. This review aims to contribute to the understanding of the interaction of polyelectrolyte-surfactant mixtures with solid surfaces, which is probably one of the most underexplored aspects of these type of systems. For this purpose, a comprehensive discussion on the correlations between the aggregates formed in the solutions and the deposition of the obtained complexes upon such association onto solid surfaces will be presented. This makes it necessary to take a closer look to the most important forces driving such processes.