Journal of Surfactants and Detergents最新文献

Nonionic surfactant vesicles (Niosomes) were prepared using a surfactant polyoxyethylene (10) stearyl ether [Brij S10] having a high hydrophile: lipophile balance (HLB). Optical and electron microscopy and light scattering indicate the stability of these vesicles. To propose the niosomal vesicles as future drug delivery systems (DDS), the morphology and bilayer characteristics of the niosomes have to be studied in detail. Insight into the niosomes could be obtained by fluorescence probing of xanthene dye aggregation. The use of Xanthene dye aggregation to probe the vesicular microenvironment has not hitherto been reported. Subsequently, we studied the entrapment and release behavior of these vesicles. The potentiality of these niosomes to entrap and release a real chemotherapeutic drug 5-fluorouracil (5-FU) was explored. Niosome-encapsulated 5-FU was administered to two breast cancer cell lines: (i) the cell line for aggressive breast cancer, that is, triple negative MDA-MB-231 and (ii) the less aggressive ER-positive MCF-7. The idea was to test the efficacy of 5-FU loaded niosomes on a cell with high metastatic potential and another with low metastatic potential. The results indicate a significant cytotoxic effect of 5-FU entrapped in niosomes on both the cell lines at less than half the IC₅₀ value of the bare drug alone.

Formulating cosmetic products to meet consumer expectations poses significant challenges in terms of stability and shelf life. This work evaluates cosmetic emulsions formulated with three commercial emulsifiers: Polyglyceryl-3 distearate (Dermofeel®, a biobased surfactant), Glyceryl stearate (50%)/PEG-100 stearate (50%) (Lipomulse®, a nonionic mixture of glyceryl and ethoxylated surfactants), and Potassium cetyl phosphate (Amphisol K®, an anionic surfactant). Additionally, three emollients, namely Caprylic/Capric Triglyceride, Isoamyl Cocoate, and Jojoba Oil, were incorporated into the formulations. The effect of emulsion composition on stability, droplet size, rheology, and texture was systematically assessed via experiments and multivariate regression modeling, thereby providing an objective tool for cosmetic emulsions formulation. The lifetime of emulsions showed that emulsions containing Potassium cetyl phosphate exhibited separation velocities larger than 60 μm/s, whereas those with the other emulsifiers showed separation velocities below 40 μm/s, indicating larger lifetimes. A predictive model based on a statistical simplex centroid experimental design was developed to evaluate the separation velocity of emulsions based on the composition of the system, enabling the assessment of important variables that influence emulsion stability. The results indicate that composition variables (such as oil concentration) and formulation variables (such as surfactant nature and oil type) are important in determining emulsion stability, but also secondary effects such as surfactant-emollient interactions are crucial to predict the lifetime of cosmetic emulsions.

Research efforts incorporating machine learning (ML) are currently focused on developing replacements for the toxic and bio-accumulative per- and polyfluorinated alkyl substances in fire suppressing foams. In the following work, ensembles of 10 artificial neural networks (ANN) were trained on a fire suppression database, described by Sudol et al., correlating area under the curve values obtained from 19-cm gasoline and heptane pool fire extinction curves to the molecular descriptors of surfactants within various firefighting foams. These ANN model ensembles were then used to evaluate proposed surfactant structures to predict the firefighting effectiveness prior to laboratory synthesis. The two most promising surfactants were a tetrasiloxane diglucoside and a chlorotrisiloxane-polyethyleneoxide (PEO). These surfactants were synthesized, and their fire extinction performances were assessed via 19-cm gasoline and heptane pool fire experiments to validate the ANN predictions. The synthesis of the demonstrably high-performing tetrasiloxane diglucoside surfactant is considered a successful ML application in the context of fluorine-free firefighting surfactant research and development. Meanwhile, the synthesis of the low-performing chlorinated PEO surfactant, which failed to meet predicted performance expectations, demonstrates the need for both comprehensive training data sets and the proper consideration of modeling redundancies to safeguard against unreliable ML-derived performance predictions.

Time-of-flight secondary ion mass spectroscopy (ToF-SIMS) was used to investigate the changes in keratin protein surface chemistry caused by the covalent bonding reactions of commercially available alkylsulfates and alkyl ethoxysulfates surfactants. Due to cystine and cysteine oxidation, plus regular shampooing, the surface chemistry of human hair is different from that of freshly scoured merino wool. Human hair can produce positive ions derived from the reaction of alkylsulfates and alkylethoxysulfates, commonly present in shampoos, with histidine and possibly lysine residues (with little evidence for cysteine thiol reaction). ToF-SIMS analysis of alkylsulfate treated keratin fibers confirmed the reaction of these surfactants with cysteine thiol, tyrosine phenolate, histidine imino, and possibly lysine amino residues. The reaction of alkylsulfates with keratin fiber surface nucleophiles is salutary since similar nucleophiles are present in skin proteins, enzymes, and DNA—which could reasonably be expected to undergo similar modification. In the case of skin, this reaction increases the surface hydrophobicity, which alters the skin biochemistry and microbiome. This results in suitable environmental conditions that could exacerbate existing afflictions such as dandruff, eczema, and mouth ulcers.

This paper describes the development of a new high-throughput (HT) method for screening surfactant additives for the removal of water from bitumen extracted from oil sands. The method begins by isolating bitumen froth from Canadian oil sands via the hot water extraction and flotation process. The froth is then diluted with naphtha to form “dilbit” The dilbit is homogenized and subsequently mixed twice to ensure a uniform distribution of water and sediment. Then, aliquots of the dilbit are dispensed into separate vials, and surfactant additives are mixed in at the desired concentrations. Next, the samples are transferred to centrifugation cells and centrifuged. Finally, the top third of the sample volume is removed, and Karl Fischer titration is used to measure the residual water. The HT method was used to screen the dewatering performances of 67 surfactants. Of the surfactants screened, (ethylene oxide)-(propylene oxide)-(ethylene oxide) (EO_x-PO_y-EOx) triblock copolymer surfactants with molecular weight (MW) values >2000 Da and hydrophilic–lipophilic balance (HLB) values <16 were found to be the most effective demulsifying additives. The research approach presented here may enable the rapid development of structure–property relationships to guide the selection of surfactant additives for the improvement of commercial bitumen froth extraction and upgrading processes.

Ensuring emulsion stability during flow is crucial across industries such as food production, petroleum, and pharmaceuticals, where optimizing emulsifier use enhances stability, reduces costs, and extends shelf life. Despite its importance, a clear approach that considers the mechanisms governing droplet size during transport remains an open area for improvement. In this study, we apply a previously proposed model to estimate the surfactant concentration required to ensure emulsion stability under flow conditions. We show that the parameters employed in the Langmuir isotherm successfully capture the key trends across most regions of the experimental data. Furthermore, we propose that a precise characterization of the coalescence dynamics of flowing droplets must account for both hydrodynamic and steric effects. By considering surfactants of different natures, we demonstrate the model's versatility and practical relevance for diverse industrial applications. We discuss our predictions compared with experimental reports and hydrodynamic theory, finding good alignment.

The utilization of sustainable feedstocks in surfactant production is crucial for reducing environmental impact, enhancing resource efficiency, and aligning with global efforts toward a circular economy and green chemistry. In this research, cellulose derivatives were synthesized by methylating cellulose fibers extracted from Guinea grass (Megathyrsus maximus) and their interfacial properties as surfactants were evaluated. The derivatives were characterized using Fourier-transform infrared spectroscopy (FTIR), which revealed distinct stretching vibration absorption bands indicative of methyl groups. Thermogravimetric analysis (TGA) identified a dual-stage decomposition process, consistent with reported behavior for methylcellulose. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) further confirmed the presence of methyl ether groups, with the H₅CO⁺ ion detected as the characteristic fragment of the methylated samples. Functional evaluations demonstrated that double-methylated cellulose derivatives exhibited a hydrophilic–lipophilic balance (HLB) of 12.7 and a surface tension of 55 dyne/cm when compared to mono or unmethylated fibers. Additionally, the double-methylated derivatives displayed enhanced foaming activity, emulsion stability, and water solubility. These cellulose-based surfactants exhibited interfacial properties comparable to their synthetic counterparts, emphasizing their potential for industrial applications and their role in advancing sustainable material development.

The phase behaviors of mixed systems comprising the amino acid surfactant potassium cocoyl glycinate (PCG) and soap-based surfactants, including potassium laurate (PL), potassium myristate (PM), potassium palmitate (PP), and potassium stearate (PS), were systematically investigated. The concentrations of the transition from spherical to rod-like micelles of the mixed system were determined using conductivity. The phase transition temperatures were determined using differential scanning calorimetry (DSC). The liquid crystal phases formed in the region of high surfactant concentration were initially investigated using polarized optical microscopy (POM), and the types of liquid crystal phases were further characterized using small-angle X-ray scattering (SAXS). Finally, the rheological behavior of different phase states was studied by varying the concentration and temperature. The results show that the mixed systems of PCG and soaps exhibit rich phase behavior, and the liquid crystal phases exhibit hexagonal and lamellar phase liquid crystals. The type of soap and the compounding ratio both affect phase behavior, specifically in terms of the extent of the phase region. Furthermore, the rheological properties of the sample are associated with the self-assembled structure of the surfactant. This study provides a reference for the application of the mixtures of amino acid surfactants and soaps in detergents and cosmetics.

This article celebrates the illustrious career and scientific legacy of Prof. Jean-Louis Salager, recipient of the prestigious Samuel Rosen Memorial Award presented by the American Oil Chemists' Society (AOCS) in April 2020. The award acknowledges his over 50 years of groundbreaking contributions to the field of surfactant chemistry, honoring individuals whose work has had a profound impact on both industry and academia. This tribute details Prof. Salager's lifelong contributions, which extend beyond his remarkable scientific discoveries to encompass a profound influence on generations of researchers, many of whom now continue his legacy across the globe. This article brings together the reflections of colleagues and collaborators from the global stage—scientists and professionals inspired by Prof. Salager's mentorship and vision, many representing the Venezuelan diaspora whose careers he shaped with his guidance and support. Together, they underscore the enduring impact of Prof. Salager as a teacher, mentor, and friend, whose work and mentorship continue to inspire and shape the field of surfactant chemistry and interfacial science around the world.