Sodium Dodecyl Sulfate Complex Research Articles

Maize‐derived zein/acrylic hybrid emulsion for superior skin adhesion and water resistance in cosmetic adhesives

AbstractWaterborne acrylic emulsions are considered suitable materials for cosmetic skin adhesives because of their positive attributes, such as their safe water‐based polymerization process and low volatile‐organic‐compound emissions. The significant challenge of inadequate water resistance in emulsion adhesives, which is primarily caused by the excess surfactants retained at the interface of emulsion particles upon film formation, necessitates urgent resolution for their viable application as cosmetic adhesives. Zein, a corn‐derived protein, possesses hydrophobic amino acids that provide exceptional water‐repellent characteristics. Therefore, zein is expected to exhibit a remarkable skin‐adhesion attribute. This paper presents the introduction of a pioneering zein/acrylic hybrid emulsion exhibiting remarkable skin adhesion and water resistance, which was achieved through the use of zein, a corn‐derived protein. After formation, the zein/ sodium dodecyl sulfate (SDS) complex can unfold the zein chain, thereby enhancing skin adhesion, while concurrently inhibiting surfactant migration to enhance water resistance. The zein/SDS complex was introduced into the Pre‐emulsion (PE) manufacturing process during emulsion polymerization. As expected, the zein/acrylic hybrid emulsion demonstrated favorable skin adhesion and a notable improvement in water resistance. This approach presents a promising avenue for the practical application of emulsion nanoparticles as eco‐friendly cosmetic adhesives, offering excellent durability and skin adhesion through the utilization of naturally derived proteins.

Supramolecular interactions in the pseudo-polyanions of polyvinylpyrrolidone complexed with various anionic surfactants

It is difficult to perform quantitative comparisons of more than two complexes between nonionic water-soluble polymers and anionic surfactants (a-surfactants) from the perspective of supramolecular interactions due to the lack of comparable parameters. Sodium dodecyl sulfate (SDS), sodium dodecylbenzene sulfonate (SDBS), sodium dodecanoate (SD) and potassium lauryl phosphate (PLP) are applied as typical a-surfactants and mixed with polyvinylpyrrolidone (PVP) to build up six complexes at different pH. These complexes are investigated by the aid of capillary electrophoresis (CE), tensiometry, conductometry, isothermal titration calorimetry, and especially pre-column derivatization CE for salt effects. Therefore, five complexation parameters are proposed from different perspectives including the low threshold of complexation [ΔC], the high threshold of complexion [Гmax], the ratio of bridging-to-diffusion counterion [B], the surface charge density [E] and the size expansion factor [S], finally comprehensive comparisons of complexes based on these parameters are realized. In general, all complexes of PVP–anionic surfactants are apparent pseudo-polyanions with the sandwich-like structure, which is mainly dependent on cation-bridging effects. Typically, the PVP–SDS complexes show the maximum [B] and [E], the second largest [ΔC] and [Гmax] but the minimum [S], demonstrating them to be the most-compact, stablest, and strongest pseudo-polyanions. On the contrary, the PVP–PLP complexes at pH 7.6 are the weakest pseudo-polyanions due to the minimum [E]. Electrolyte strengths of the pseudo-polyanions are mainly dominated by the cation-bridging degree (1 – α12) rather than the ionization degree (α12) of polymer–bound micelles.

Quality by Design-Based Development of Solid Self-Emulsifying Drug Delivery System (SEDDS) as a Potential Carrier for Oral Delivery of Lysozyme.

For many years, researchers have been making efforts to find a manufacturing technique, as well as a drug delivery system, that will allow for oral delivery of biopharmaceuticals to their target site of action without impairing their biological activity. Due to the positive in vivo outcomes of this formulation strategy, self-emulsifying drug delivery systems (SEDDSs) have been intensively studied in the last few years as a way of overcoming the different challenges associated with the oral delivery of macromolecules. The purpose of the present study was to examine the possibility of developing solid SEDDSs as potential carriers for the oral delivery of lysozyme (LYS) using the Quality by Design (QbD) concept. LYS was successfully ion paired with anionic surfactant, sodium dodecyl sulphate (SDS), and this complex was incorporated into a previously developed and optimized liquid SEDDS formulation comprising medium-chain triglycerides, polysorbate 80, and PEG 400. The final formulation of a liquid SEDDS carrying the LYS:SDS complex showed satisfactory in vitro characteristics as well as self-emulsifying properties (droplet size: 13.02 nm, PDI: 0.245, and zeta potential: -4.85 mV). The obtained nanoemulsions were robust to dilution in the different media and highly stable after 7 days, with a minor increase in droplet size (13.84 nm) and constant negative zeta potential (-0.49 mV). An optimized liquid SEDDS loaded with the LYS:SDS complex was further solidified into powders by adsorption onto a chosen solid carrier, followed by direct compression into self-emulsifying tablets. Solid SEDDS formulations also exhibited acceptable in vitro characteristics, while LYS preserved its therapeutic activity in all phases of the development process. On the basis of the results gathered, loading the hydrophobic ion pairs of therapeutic proteins and peptides to solid SEDDS may serve as a potential method for delivering biopharmaceuticals orally.

Investigation of critical micelles concentration of saccharide-surfactant-polymer complex

The diverse application of β-cyclodextrin grabbed the attention of research community. The encapsulation of hydrophobic molecules was the unique property of the β-cyclodextrin that suggested its application in enhanced oil recovery system. The well known Xanthan gum was one suggested polymer that could have its potential use in enhanced oil recovery systems along with the surfactant sodium dodecyl sulfate. However, this polymer surfactant complex show shear thinning behavior, the presence of β-cyclodextrin could alter the micelles structure. The present work focuses on the investigation of critical micelles concentration (CMC) of Xanthan gum, sodium dodecyl sulfate and β-cyclodextrin complex. Both conductivity and surface tension were followed to evaluate the critical micelles concentration of the complex at various β-cyclodextrin compositions in the mixture. The self assembly of the complex mixture shows reduction in the critical micelles concentration of the solutions.

Investigation of polymer−surfactant complexes by both micellar solubilization and pre-column derivatization capillary electrophoresis

“Pseudo-polyanions” are formed in some mixtures of nonionic water-soluble polymers and anionic surfactants with ultraviolet (UV) absorption signals, which is verified by capillary electrophoresis (CE) equipped with an UV detector. However, it is still unclear whether two typical mixtures of PEG (polyethylene glycol)−LDS (lithium dodecylsulfate) and PEG−SDS (sodium dodecylsulfate) are pseudo-polyanions or not due to lack of necessary UV absorption. Therefore, with the help of UV probes or UV labeling reagents, micellar solubilization CE and pre-column derivatization CE are implemented to make the mixtures detectable or “visible” by a UV detector. Experimental results show that both PEG–LDS and PEG–SDS complexes are pseudo-polyanions verified by the above strategies. Combined with previous works, most mixtures of nonionic water-soluble polymers and anionic surfactants can form unique pseudo-polyanions by dint of ion bridge no matter whether with or without UV absorption. What’s more, the bridging-to-diffusion ion ratio and the charge-to-size ratio of pseudo-polyanions are dominated by the bridging ions, and the smaller the hydrated ionic radius (H+ < K+ < Na+ < Li+) is, the stronger the polyanion nature is.

Time-resolved detection of SDS-induced conformational changes in α-synuclein by a micro-stopped-flow system.

An intrinsically disordered protein, α-synuclein (αSyn), binds to negatively charged phospholipid membranes and adopts an α-helical structure. This conformational change is also induced by interaction with sodium dodecyl sulfate (SDS), which is an anionic surfactant used in previous studies to mimic membrane binding. However, while the structure of the αSyn and SDS complex has been studied widely by various static measurements, the process of structural change from the denatured state to the folded state remains unclear. In this study, the interaction dynamics between αSyn and SDS micelles was investigated using time-resolved measurements with a micro-stopped-flow system, which has been recently developed. In particular, the time-resolved diffusion based on the transient grating technique in combination with a micro-stopped-flow system revealed the gradual change in diffusion triggered by the presence of SDS micelles. This change is induced not only by binding to SDS micelles, but also by an intramolecular conformational change. It was interesting to find that the diffusion coefficient decreased in an intermediate state and then increased to the final state in the binding reaction. We also carried out stopped-flow-kinetic measurements of circular dichroism and intramolecular fluorescence resonance energy transfer, and the D change was assigned to the formation of a compact structure derived from the helix bending on the micelle.

Comparison of dye (oxazine and thiazine) materials as a photosensitizer for use in photogalvanic cells based on molecular interaction with sodium dodecyl sulphate by spectral study

The photochemistry of dye is playing a significant role for understanding the mechanism of electron transfer reactions in photoelectrochemical devices such as photogalvanic cells, DSSC, semiconductor photo-catalysis, photoconductors, etc. Oxazines (Brilliant Cresyl Blue and Nile Blue O) and thiazines (Azur A, Azur B, Azur C, Methylene Blue and Toluidine Blue O) dyes have been used widely as a photosensitizer with and without surfactants in the photogalvanic cells for solar power conversion and storage. Since, the stability and solubility of photosensitizers (dyes) are increased in the presence of surfactant and these properties lead to enhance the electrical output of the photogalvanic cells. Therefore, here we have studied the extent of interaction of different dyes with sodium dodecyl sulphate (SDS), find out the order of stability of dye–SDS on the basis of magnitudes of shifting in λmax of dye monomer and try to correlate order of dye–SDS interaction with already reported electrical output data of photogalvanic cells. Brilliant Cresyl Blue, Nile Blue O, Azur A and TB O have shown red shifting while Azur B, Azur C and MB have shown blue shifting in their λmax value with SDS, which indicates formation of dye–surfactant complex. But, the extent of formation of complex for different dyes with SDS was different due to change in their alkyl groups. Dyes with red shifting have greater stability in excited state as well as higher electrical output data of the cell than dye with blue shifting. On the basis of both red and blue shifting, order of stability of dyes–SDS complex was found as: Brilliant Cresyl Blue > Toluidine Blue O > Azur A > Nile Blue > Azur B > Methylene Blue > Azur C. The order of electrical output values of these dyes in photogalvanic cells have also been supported by literature data in the presence of SDS. Hence, the dye–surfactant complex which would have greater stability in excited state might be more useful for improvement of conversion efficiency and storage capacity of photogalvanic cells in the future.

Analysis of natural gas hydrate formation in sodium dodecyl sulfate and quartz sand complex system under saline environment

ABSTRACTUnder natural conditions, natural gas hydrate occurs in the pores of porous media found in the sedimentary layer. Thus, the rapid formation and basic properties of the hydrate in the porous medium must be studied. Quartz sand with different particle sizes compounded with Sodium Dodecyl Sulfate solution was used to study the hydrate formation in the system at 275.15 K and 6 MPa under a saline environment. Results were as follows. 1) Methane gas uptake in a saline system with NaCl concentration of 50 mmol was higher than that in pure water. This finding indicated that although the salt is a thermodynamic inhibitor, low concentration of NaCl can promote the formation of hydrates. 2) In the initial stage of the experiment, the rate of hydrate formation in saline environment was significantly higher than that in pure water. After approximately 1 h, the formation rate of hydrate in the compound system decreased under a saltwater environment and was lower than that in the complex system under pure water. 3) The hydrogen bond network inside the high-concentration NaCl solution was seriously damaged. In this case, water molecules cannot easily form a cage structure, and the presence of chlorine ions weakens the stability of a small amount of formed hydrate cage, thereby further inhibiting the formation of hydrates. However, in the low-concentration NaCl system, mass transfer is improved, and the formation of hydrate is promoted because of the weakened hydrogen bonding at the gas–liquid interface.

Effect of Porous Media and Sodium Dodecyl Sulphate Complex System on Methane Hydrate Formation

Hydrates are mainly stored in the pores of the sedimentary layer, so their formation and storage characteristics in pores are particularly important for the exploitation and utilization of hydrates. Meanwhile, in order to study the rapid formation methods of hydrate, 300 ppm of sodium dodecyl sulfate (SDS) solutions mixed with alumina and silica particles, respectively, were used for investigating the hydrate formation in the pores of porous media under the conditions of 275.15 K and 7 MPa. The particle sizes of alumina and silica were 2, 4, and 6 mm. The experimental results indicated porous media with smaller size could shorten the induction time of the hydrate formation and increase the final gas uptake. In dissolution period and induction period, gas consumption of hydrate formation in alumina particles was larger than that in silica, but the reverse in the growth period. The hydrate formed in alumina particles had a better gas storage ability. In the used SDS solution, the positive charges produced by hydrolysis on the alumina surface and the negative charges produced by polarization and hydration on silica surface affected the distribution of the SDS active group around their surface, which led to the difference of gas storage density between the hydrates formed in these two particles. Finally, with the formation of the hydrate on the wall of the porous medium, the stronger capillary force caused by the decreasing pore size led to a migration of water, which further resulted in the hydrate form in the pores without SDS solution originally.

Quantum chemical study of the molecular structure of the sodium dodecylsulfate complexes with glycine and cysteine

The quantum chemical modeling of sodium dodecylsulfate (DDSNa) complexes with glycine (Gly) and cysteine (Cys) is carried out at the DFT/B97D level using the Grimme hybrid exchange-correlation functional with a dispersion correction and the 6-311++G(2d,2p) basis set. The structure of the Gly and Cys molecular and zwitterionic forms is examined. The structures and the formation energies of DDSNa…Gly and DDSNa…Cys complexes are determined. The effect of the amino acid structural features on the stability of the complexes they form with DDSNa is analyzed. The NBO analysis of the electron density distribution in the DDSNa molecule is performed.

Folate-conjugated thermosensitive O-maleoyl modified chitosan micellar nanoparticles for targeted delivery of erlotinib

In the present work, new self-assembled nanoparticles (NPs) were engineered using biocompatible and biodegradable natural polymer, chitosan (CS). The complexation of CS with sodium dodecyl sulfate (SDS) facilitated the regioselective chemical modification of CS hydroxyl groups with maleic anhydride, and produced polymerizable precursor of CS that was further grafted with N-isopropylacrylamide (NIPAAm) as temperature-sensitive moiety and oleic acid (OA) as hydrophobic monomer. After removal of SDS complex, the free amino groups were functionalized with folic acid (FA) to form folate-(PNIPAAm-co-OA)-g-CS micellar NPs. The NPs were loaded with a tyrosine kinase inhibitor erlotinib (ETB), which was carried out above the lower critical solution temperature (LCST) of micelles solution. The structure, size distribution, zeta potential, thermal stability, elemental composition, morphology and LCST of the synthesized micelles were characterized. The cellular uptake and cell cytotoxicity analyses revealed that the developed smart folate-(PNIPAAm-co-OA)-g-CS micellar NPs could be used for effective cancer therapy as an injectable tumor targeting nanocarrier.

Harnessing the interaction between surfactant and hydrophilic catalyst to control eATRP in miniemulsion.

In contrast with previous accounts, it is reported that a single, strongly hydrophilic Cu complex can control an electrochemically mediated atom transfer radical polymerization (eATRP) in oil-in-water miniemulsion in the presence of anionic surfactants, such as sodium dodecyl sulfate (SDS). The anionic surfactant interacted strongly with cationic copper complexes, enabling controlled polymerization by a combination of "interfacial" and "ion-pair" catalysis, whereby ion pairs transport the catalyst to the monomer droplets. The ion-pair system was assembled in situ by mixing commercially available reagents (NaBr, SDS, and traditional hydrophilic copper complexes). Polymer purification was very facile because after reaction >99% of the hydrophilic copper complexes spontaneously left the hydrophobic polymer particles.

Evaporation of aqueous solutions of organic acids through spread films of poly(diallyldimethylammonium chloride)/sodium dodecylsulfate complex

ABSTRACTThe films with the extreme concentration of poly (diallyldimethylammonium chloride)/sodium dodecylsulfate complex spread to the surface of aqueous solutions of formic and acetic acids reduce the evaporation rate of liquids by 3–6% and demonstrate selective properties increasing water content in the vapor by 1–3 abs.%. The concentrations of solutions were up to 30 vol.%. The formation conditions of such films were determined by means of the Wilhelmy plate technique. Surface tension isotherms of aqueous solutions of acids were also obtained.

Квантово-химическое исследование молекулярного строения комплексов додецилсульфата натрия с глицином и цистеином

Квантово-химическое исследование молекулярного строения комплексов додецилсульфата натрия с глицином и цистеином

Exploring the Nature of the Nanocavity and Channels in Apoferritin and Apoferritin–Sodium Dodecyl Sulfate Complex Using an Enhanced Antenna Effect through the Encapsulation of EuIII–Tetracycline

The drug tetracycline hydrochloride (TC), which has cytotoxic and cytostatic effects on tumor cells, has been encapsulated within the nanocavity of apoferritin in the form of its EuIII complex (Eu3TC). The Eu3TC complex was encapsulated within apoferritin through disassembly followed by reassembly of the protein and exhibited significantly enhanced EuIII emission in comparison with that of free Eu3TC in aqueous buffer at pH 8. The steady‐state and transient measurement of the emission of each species in the ternary system suggest that the effective sensitization of EuIII emission may be ascribed to a comparatively rigid environment for the bound TC after encapsulation that promotes efficient energy transfer to the EuIII ions. Emission studies in D2O revealed that the microenvironment of the EuIII ion is shielded from O–H oscillators in the ternary system, and the extent of shielding is greater after the encapsulation of the complex within the apoferritin cavity. The rotational correlation time (θc) of bound TC and docking studies also support the contention that the TC is in a more buried environment after encapsulation within the apoferritin cavity. A competition study with sodium dodecyl sulfate (SDS) revealed that SDS does not interfere with the binding of TC to apoferritin. The biocompatible system consisting of Eu3TC encapsulated within the cavity of apoferritin may be used as an efficient targeted drug transporter, and the sensitization of the EuIII emission may also enable its use as a biosensor.

Insights into the morphology of human serum albumin and sodium dodecyl sulfate complex: A spectroscopic and microscopic approach

Exploring and understanding the fundamental interaction between protein and surfactant is utmost important for various pharmaceutical and biomedical applications. However, very less is known about the arrangement of individual negatively charged sodium dodecyl sulfate (SDS) molecules on the human serum albumin (HSA). Here, we have investigated the morphology and mechanistic insights of complexation between HSA and SDS by means of photoluminescence (PL) spectroscopy, circular dichroism (CD) and PL microscopy using amine-functionalized silicon quantum dot (Si QD) as an external luminescent marker. The present study is based on a unique and dynamic SDS-Si QD system. The synthesized allylamine–functionalized Si QDs show a distinct PL band centered at 455nm upon excitation at 375nm. At neutral pH, these Si QDs form ordered aggregates in the presence of 1mM SDS due to the hydrogen bonding interaction with the sulfate head groups of surfactants, which is manifested in the appearance of a large Stokes shifted luminescence band centered at 610nm. It has been observed that the PL intensity of SDS-Si QD aggregates at 610nm decreases gradually with concomitant increase in the PL intensity of monomeric Si QDs at 455nm upon increasing the concentration of HSA from 1 to 10μM. These observations combined with PL lifetime, PL microscopy and CD results reveal that SDS forms micelle-like aggregates on the partially unfolded HSA mainly via electrostatic interaction between negatively charged sulfate head groups and positively charged residues of partially unfolded HSA. For the present HSA-SDS system, our results fit a model with type I “necklace and bead”-like structures, where micelle-like SDS aggregates wrap around by the partially unfolded HSA backbone.

Supersaturated polymeric micelles for oral cyclosporine A delivery: The role of Soluplus–sodium dodecyl sulfate complex

Our previous study demonstrated that the retention of drug in the hydrophobic core of Soluplus micelle greatly impeded drug absorption from gastrointestinal tract. Using supersaturated polymeric micelles can improve drug release, however, insufficient maintaining of supersaturation of drug is still unfavorable for drug absorption. Here, we report adding small amount of small molecule, sodium dodecyl sulfate (SDS), to Soluplus solution can form a Soluplus–SDS complex. This complex not only showed a higher solubilization capability for the model drug cyclosporine A (CsA), but also maintained a longer period of and higher supersaturation than was achieved with Soluplus alone. The Soluplus–SDS interactions were characterized by analyzing surface tension, small-angle X-ray scattering (SAXS), fluorescence spectra, and nuclear magnetic resonance spectroscopy. The results demonstrated that the formation of Soluplus–SDS complex via SDS adsorption on hydrophobic segments of Soluplus, which have more hydrophobic domain than that of Soluplus micelle, contributed significantly to the solubilization and stabilization of supersaturated CsA. Using this amphiphilic copolymer-small molecule surfactant system, the cellular uptake and rat in vivo absorption of CsA were more effectively achieved than pure Soluplus. The area under the plasma concentration-time curve (AUC) and the maximal plasma concentration (Cmax) achieved by CsA-loaded Soluplus–SDS complex were 1.58- and 1.8-times higher than the corresponding values for CsA-loaded pure Soluplus, respectively. This study highlighted the benefits of Soluplus–SDS complex for optimizing the solubilization and oral absorption of a drug with low aqueous solubility.

Combined use of surfactant-induced coagulation of poly(allylamine hydrochloride) with peroxidase-mediated degradation for the rapid removal of estrogens and phenolic compounds from water

Sodium dodecyl sulfate (SDS)-induced coagulation of poly(allylamine hydrochloride) [PAH] was studied for the rapid removal of estrogens and phenolic compounds from water. When electrically equivalent amount (62mgL−1) of SDS was added into the aqueous solution of 20mgL−1 PAH with vigorous mixing, PAH was quantitatively (>99%) recovered from water as condensed aggregates of PAH–SDS complexes. According to the fluorescence spectrum of a molecular probe, the complexes provided hydrophobic regions suitable for incorporating hydrophobic organic pollutants. However, rather polar estrone, β-estradiol, estriol, and ethynylestradiol were insufficiently removed. Combined use of horseradish peroxidase (HRP) and hydrogen peroxide significantly increased the collection yields of these estrogens, because of their HRP-induced oxidation of and spontaneous binding to PAH. With the HRP activity of 100UL−1 and the hydrogen peroxide concentration of 10mgL−1, nearly complete (>98%) removal of four estrogens was achieved within 10min at 30°C in the pH region from 6 to 7.5. The method was also useful for the rapid removal of different phenolic compounds and selected pharmaceuticals. The applicability to wastewater treatment was successfully demonstrated by using secondary effluents.

Modification of PTFE latex with P4VP/Surfactant complexes at nanoscale

Polytetrafluoroethylene (PTFE) latex nanoparticles were subjected to modification with Poly (4-vinylpyridine) (P4VP) by in situ seeded emulsion polymerization technique using regular [sodium dodecyl sulfate (SDS)] and fluorinated [Potassium heptadecafluoro-1-octanesulfonate (PFS)]surfactants. The as prepared PTFE- (P4VP/surfactant complex) composite latex nanoparticles were characterized for structure, morphology, and thermal properties and a comparison of particles obtained by PFS and SDS was done with different W/W ratios of PTFE and 4VP monomer. The composites have shown a multistep degradation pattern that may be attributed to the P4VP, surfactant and PTFE backbone degradation. Lowering of crystal–crystal transition temperature of PTFE and increase in the glass transition temperature of the P4VP/PFS or SDS complexes was noticed in all the composites suggesting a homogeneous modification. Thus, a simple and easy way to modify PTFE has been reported which could be subsequently complexed with metal salts such that stringent high energy pretreatment methods like plasma, ozone, or irradiation techniques could be avoided. POLYM. ENG. SCI., 55:499–505, 2015. © 2014 Society of Plastics Engineers

Cu nanoparticles of low polydispersity synthesized by a double-template method and their stability

Cu nanoparticles of well-defined size and stability were synthesized with the aid of a double-template method. The templates consisted of sodium dodecyl sulfate (SDS) aggregates combined with and wrapped by poly(vinylpyrrolidone) (PVP) chains. Copper sulfate was reduced within the templates resulting in multicrystalline Cu nanoparticles. The size of the particles was uniform. They were capped by PVP–SDS complexes and the shape turned out to be non-spherical. PVP used in the experiments has an average molecular weight of 40,000. In this case, the particle dimensions were essentially determined by the chosen concentration of SDS in the reaction solution. No oxidation of the as-grown copper particles was detected even in the absence of inert gas protection during the synthesis process. When exposed to air at room temperature, Cu nanoparticles capped by PVP–SDS complexes showed much better resistance to oxidation than those without the capping agents. Furthermore, the steric and screening effect of the capping agents permitted the preparation of uniform colloidal dispersions stable over months. The material obtained by this double-template method was found to be very sensitive to the synthesis temperature. At synthesis temperatures above 40 °C, CuO instead of Cu was obtained.