Search Results (183)

Surfactants are widely utilized in agriculture as emulsifying, dispersing, anti-foaming, and wetting agents. In these adjuvant roles, the inherent biological activity of the surfactant is secondary to the active ingredients. Here, the hydrophilic non-ionic surface-active tri-block copolymer Pluronic^® F68 is investigated for direct biological activity in wheat. F68 binds to and inserts into lipid membranes, which may benefit crops under abiotic stress. F68’s interactions with Triticum aestivum (var Juniper) seedlings and a seed-borne Bacillus spp. endophyte are presented. At concentrations below 10 g/L, F68-primed wheat seeds exhibited unchanged emergence. Root-applied fluorescein-F68 (fF68) was internalized in root epidermal cells and concentrated in highly mobile endosomes. The potential benefit of F68 in droughted wheat was examined and contrasted with wheat treated with the osmolyte, glycine betaine (GB). Photosystem II activity of droughted plants dropped significantly below non-droughted controls, and no clear benefit of F68 (or GB) during drought or rehydration was observed. However, F68-treated wheat exhibited increased transpiration values (for watered plants only) and enhanced shoot dry mass (for watered and droughted plants), not observed for GB-treated or untreated plants. The release of seed-borne bacterial endophytes into the spermosphere of germinating seeds was not affected by F68 (for F68-primed seeds as well as F68 applied to roots), and the planktonic growth of a purified Bacillus spp. seed endophyte was not reduced by F68 applied below the critical micelle concentration. These studies demonstrated that F68 entered wheat root cells, concentrated in endosomes involved in transport, significantly promoted shoot growth, and showed no adverse effects to plant-associated bacteria. Full article

Mannosyl erythritol lipids (MELs) are glycolipid biosurfactants produced by Ustilaginomycete yeasts. The MEL biosynthetic pathway has been characterized in Ustilago maydis where a putative transporter encoded by MMF1 is required for the secretion of the glycolipid surfactant to the extracellular space. The anamorphic yeast Moesziomyces antarcticus is a prolific producer of MELs, but the mechanism of MEL secretion is less well characterized than in U. maydis. Homologous recombination was employed to generate a disruption of the MMF1 gene in M. antarcticus JCM10317. This mutation did not prevent the intracellular accumulation of MEL species but did result in significantly reduced secretion of the conventional MEL-A, MEL-B and MEL-C species detectable by thin-layer chromatography. However, the mutant strain did secrete a glycolipid species that is distinct from conventional MEL-A/B/C and similar to a glycolipid secreted by MMF1 mutant strains of U. maydis and Pseudozyma tsukubaensis. Despite the defect in MEL secretion displayed by the M. antarcticus strain harbouring a disrupted MMF1 gene, these cells did not display a significant defect in growth or cell morphology. The findings of this investigation provide evidence that M. antarcticus MMF1 encodes a transporter required for the secretion of MELs but not required for MEL synthesis or cell growth. Full article

The development of nanocarriers for drug delivery has drawn a lot of attention due to the possibility for tailored delivery to the ill region while preserving the neighboring healthy tissue. In medicine, delivering drugs safely and effectively has never been easy; therefore, the creation of surfactant-based vesicles (niosomes) to enhance medication delivery has gained attention in the past years. Niosomes (NIOs) are versatile drug delivery systems that facilitate applications varying from transdermal transport to targeted brain delivery. These self-assembling vesicular nano-carriers are formed by hydrating cholesterol, non-ionic surfactants, and other amphiphilic substances. The focus of the review is to report on the latest NIO-type formulations which also include biopolymers from the polysaccharide class, highlighting their role in the development of these drug delivery systems (DDSs). The NIO and polysaccharide types, together with the recent pharmaceutical applications such as ocular, oral, nose-to brain, pulmonary, cardiac, and transdermal drug delivery, are all thoroughly summarized in this review, which offers a comprehensive compendium of polysaccharide-based niosomal research to date. Lastly, this delivery system’s limits and prospects are also examined. Full article

Pollen allergy is rated as a major public health problem, causing significant morbidity and adversely affecting the quality of people’s lives. The airway epithelium serves as the first line of defense in the respiratory system, playing a crucial role in orchestrating immune responses to allergens. In this work, we studied the important transport steps in the major alder pollen allergen Aln g 1 through the human airway epithelium in comparison with those of the birch pollen allergen Bet v 1. Using fluorescence spectroscopy, we showed that both allergens can destroy liposomes with a composition modeling the adult human pulmonary surfactant. Using a polarized Calu-3 monolayer, we showed similar efficiencies of Aln g 1 and Bet v 1 transport through the artificial epithelial barrier. Using qPCR, we showed that Aln g 1 upregulates the expression of IL-33, TSLP, IL-1β, CXCL8 in epithelial cells, playing an important role in the sensitization process. The obtained results may improve our understanding of the primary sensitization mechanisms with the involvement of the PR-10 family of lipid-binding allergens. Full article

Background: Sufficient choline supply is essential for tissue functions via phosphatidylcholine and sphingomyelin within membranes and secretions like bile, lipoproteins and surfactant, and in one-carbon metabolism via betaine. Choline requirements are linked to age and genetics, folate and cobalamin via betaine, and arachidonic (ARA) and docosahexaenoic (DHA) acid transport via the phosphatidylcholine moiety of lipoproteins. Groups at risk of choline deficiency include preterm infants, children with cystic fibrosis (CF) and patients dependent on parenteral nutrition. Fortifiers, formula and supplements may differently impact their choline supply. Objective: To evaluate added amounts of choline, folate, cobalamin, ARA and DHA in fortifiers, supplements and formula used in pediatric care from product files. Methods: Nutrient contents from commonly used products, categorized by age and patient groups, were obtained from public sources. Data are shown as medians and interquartile ranges. Results: 105 nutritional products including fortifiers, formula and products for special indications were analyzed. Choline concentrations were comparable in preterm and term infant formulas (≤6 months) (31.9 [27.6–33.3] vs. 33.3 [30.8–35.2] mg/100 kcal). Products for toddlers, and patients with CF, kidney or Crohn’s disease showed Choline levels from 0 to 39 mg/100 kcal. Several products contain milk components and lecithin-based emulsifiers potentially increasing choline content beyond indicated amounts. Conclusions: Choline addition is standardized in formula for term and preterm infants up to 6 months, but not in other products. Choline content may be higher in several products due to non-declared sources. The potential impact of insufficient choline supply in patients at risk for choline deficiency suggests the need for biochemical analysis of products. Full article

Zinc–manganese dioxide (Zn–MnO₂) batteries, pivotal in primary energy storage, face challenges in rechargeability due to cathode dissolution and anode corrosion. This review summarizes cathode-free designs using pH-optimized electrolytes and modified electrodes/current collectors. For electrolytes, while acidic systems with additives (PVP, HAc) enhance ion transport, dual-electrolyte configurations (ion-selective membranes/hydrogels) reduce Zn corrosion. Near-neutral strategies utilize nanomicelles/complexing agents to regulate MnO₂ deposition. Moreover, mediators (I⁻, Br⁻, Cr³⁺) reactivate MnO₂ but require shuttle-effect control. For the electrodes/current collectors, electrode innovations including SEI/CEI layers and surfactant-driven phase tuning are introduced. Electrode-free designs and integrated “supercapattery” systems combining supercapacitors with Zn–MnO₂/I₂ chemistries are also discussed. This review highlights electrolyte–electrode synergy and hybrid device potential, paving the way for sustainable, high-performance Zn–MnO₂ systems. Full article

Erythrocytes, the most abundant blood cells, are a prevalent cell model for the analysis of the membrane-damaging effects of different molecules, including drugs. In response to stimuli, erythrocytes can change their morphology, e.g., shape or volume, which in turns influences their main function to transport oxygen. Membrane active molecules can induce hemolysis, i.e., release of hemoglobin into the blood plasma. Free hemoglobin in the blood circulation is toxic causing serious health problems including vasoconstriction, high blood pressure and kidney damage. Therefore, early recognition of the risk of massive hemolysis is highly important. Here, we investigated surfactant induced hemolysis applying UV–vis spectrophotometry. Saponin, sodium dodecyl sulfate and Triton X-100, detergents known to provoke hemolysis at different concentrations and by different mechanisms, were applied to initiate the process. Whole absorption spectra of erythrocyte suspensions in the range 300–750 nm were recorded every 15 s for following the process in real-time. The hemolysis process, with respect to morphological changes in the erythrocytes and their influence on the oxygenation state of hemoglobin, was characterized by the absorbance at 700 nm, the height relative to the background and the wavelength of the Soret peak. The results suggest that these UV–vis spectrophotometry parameters provide reliable information in real-time; not only about the process of hemolysis itself, but also about pre-hemolytic changes in the erythrocytes, even at sub-hemolytic surfactant concentrations. Full article

Surfactants significantly influence the flow patterns of gas-liquid two-phase flows. Understanding the behavior of multiphase flows in the presence of surfactants is crucial for optimizing hydrate transport in pipelines. This study presents experimental investigations into the effects of surfactant-induced surface tension variations on gas-liquid two-phase spiral flows in horizontal pipelines. Four distinct flow patterns were identified: spiral linear flow, spiral wave-stratified flow, spiral axial flow, and spiral dispersed flow. Notably, spiral bubbly flow and spiral slug flow were absent in gas-liquid two-phase spiral flows with a low concentration of the anionic surfactant sodium dodecyl sulfate (SDS). A flow pattern map was developed to describe gas-liquid two-phase spiral flows in horizontal pipelines with low SDS concentrations. The results indicate that increasing the liquid-phase velocity reduces the spiral diameter and attenuates the flow patterns while increasing the pitch of the spiral flows. Furthermore, at a constant gas-phase void fraction, the pressure drop is highest in spiral wave-stratified flow and lowest in spiral dispersed flow. Full article

Using microemulsions (µEs) as preservation media for cells was pursued in the 1990s; however, the difficulty in formulating biocompatible µEs and keeping unacclimatized cells alive for more than three days hindered developments in this area. This work explores the use of fully dilutable self-microemulsifying delivery systems (SMEDS) formulated with lecithin (Le) and polyglycerol-10-caprylate (PG10C) at a ratio of 2/5. This surfactant blend was mixed with ethyl oleate (EOL) at a ratio of 60 surfactant/40 EOL to produce a D60 dilution line. This D60 SMEDS was diluted with 0.9% w/v NaCl solution to produce lecithin-linker µEs (LLMs). The properties of the resulting LLMs were predicted using the hydrophilic–lipophilic-difference (HLD) and net-average curvature (NAC) model, indicating that LLMs with aqueous content from 5% to 60% are bicontinuous, confirmed via viscosity and conductivity. The largest yeast activity and viability obtained with LLMs were achieved with 30% aqueous content, resulting from the balance between having enough water for the effective transport of metabolites, enough SMEDS to contribute nutrients and lipids, and a low enough water to limit the partition of PG10C that, when present in the aqueous phase, inhibited yeast activity. For SMEDS, its low water activity ensured that the yeast remained dormant, keeping them alive for at least 10 weeks. Full article

Sulfonylureas (SUs)—a class of drugs primarily used to treat type 2 diabetes—have recently attracted interest for their potential anticancer properties. While some studies have explored the chemical modification or design of new SU derivatives, our work instead centers on biological evaluations of all commercially available SUs in combination with doxorubicin (DOXO). These antidiabetic agents act by stimulating insulin secretion via K_ATP channel inhibition, and because K_ATP channels share structural features with ATP-binding cassette (ABC) transporters involved in multidrug resistance (e.g., P-glycoprotein, MRP1, and MRP2), SUs may also reduce cancer cell drug efflux. In this study, we systematically examined each commercially available SU for potential synergy with DOXO in a panel of human cancer cell lines. Notably, combining DOXO with glimepiride (GLIM), the newest SU, results in a 4.4-fold increase in cytotoxicity against MCF-7 breast cancer cells relative to DOXO alone. Mechanistic studies suggest that the observed synergy may arise from increased intracellular accumulation of DOXO. Preliminary in vivo experiments support these findings, showing that DOXO (5 mg/kg, i.v.) plus GLIM (4 mg/kg, i.p.) is more effective at inhibiting 4T1 tumor growth in mice than DOXO alone. Additionally, we show that adding a small amount of the surfactant Tween-80 to culture media affects SU binding to bovine serum albumin (BSA), potentially unmasking anticancer effects of SUs that strongly bind to proteins. Overall, these results underscore the potential of repurposing existing SUs to enhance standard chemotherapy regimens. Full article

Hydraulic fracture stimulation is one of the most effective methods to recover oil and gas from unconventional resources. In recent years, foam-based fracturing fluids have been increasingly studied to address the limitations of conventional slickwater such as high water and chemical consumption, environmental concerns, and high incompatibility with water-sensitive formations. Due to the gradual breakdown of liquid foams at reservoir conditions, the combination of silica nanoparticles (SNP) and surfactants has attracted a lot of attention to improve liquid foams’ characteristics, including their stability, rheology, and proppant-carrying capacity. This paper investigates and compares the effects of cationic and anionic surfactants on the fracturing performance of SNP-stabilized foams at the reservoir temperature of 90 °C. The experimental results of viscosity measurements were imported into a 3D fracture-propagation model to evaluate the effectiveness of fracturing foams in transporting and distributing proppants in the fracture system. At both ambient and elevated temperatures, cationic surfactant was experimentally found to have better synergistic effects with SNP than anionic surfactant in improving the apparent viscosity and proppant-carrying capacity of foams. The simulation results demonstrate that fracturing with cationic surfactant-SNP foam delivers greater performance with larger propped area by 4%, higher fracture conductivity by 9%, and higher cumulative gas production by 13%, compared to the anionic surfactant-SNP foam. This research work not only helps validate the interrelationship between fluid viscosity, proppant settlement rate, and fracture effectiveness, but it also emphasizes the importance of proppant placement in enhancing fracture conductivity and well productivity. Full article

This study investigates the structural and transport properties of SDS, CTAB, and SB3-12 micelles in three deep eutectic solvents (DESs), Ethaline, Glyceline, and Reline, using molecular dynamics (MD) simulations. The influence of solvent composition on micelle morphology, interactions, and dynamics was explored, revealing key differences driven by the DES environment. Structural analyses, including eccentricity and radius of gyration, demonstrated that micelle shape and compactness vary significantly depending on the solvent. In Ethaline and Reline, larger micelles showed significant deviations from spherical shapes, while micelles in Glyceline became more spherical and compact, particularly those formed by SB3-12. Radial distribution functions highlighted different levels of micelle–solvent interactions, with SDS showing strong interactions with HBD components and SB3-12 exhibiting prominent self-interaction. According to hydrogen bonding analysis, micelles slightly disrupt the DES hydrogen bond network, with SB3-12 establishing the most significant hydrogen bond connections. The transport property analysis revealed that larger micelles have lower diffusion coefficients, whereas smaller micelles enhance DESs’ component mobility. These findings advance the understanding of micelle behavior in DESs and also help in the optimization of DES–surfactant systems for applications such as electrodeposition, nanomaterial templating, and drug delivery. Future research will focus on surfactant interactions with surfaces to further improve these applications. Full article

Aqueous film-forming foam (AFFF) is widely recognized for its excellent fire-extinguishing capabilities, yet the specific roles of its components remain insufficiently understood. AFFF typically consists of fluorocarbon and hydrocarbon surfactants, as well as organic solvents such as diethylene glycol butyl ether (DGBE), which can significantly influence foam performance. This study investigates the effects of surfactant mixtures and the DGBE additive on foam stability and fuel resistance at room temperature and ambient humidity. Static foam ignition experiments were conducted to assess fuel transport through foams using various hydrocarbon fuels, including n-octane, iso-octane, n-heptane, methylcyclohexane, methylcyclopentane, and a mixture of 25% trimethylbenzene with 75% n-heptane. Methylcyclopentane, with its higher vapor pressure and solubility, led to the shortest ignition times, indicating faster fuel transport. The addition of DGBE increased ignition times by a factor of 1.2 to 3.7 for individual surfactants, while the Capstone+Glucopon mixture improved ignition times by a factor of 2.4 to 5.5 compared to the individual surfactants. Further enhancement was observed with Capstone+Glucopon+DGBE, increasing ignition times by a factor of 3 to 7.3 compared to the individual surfactants. Additionally, combining DGBE with surfactant mixtures reduced fuel concentration in the bulk solution by over 60% compared to individual surfactants, significantly enhancing fuel resistance. Interface experiments showed that fuel presence, particularly methylcyclopentane and n-octane, altered the foam structure and accelerated drainage at the foam/fuel interface, impacting foam stability and fuel transport. These findings demonstrate that surfactant mixtures and DGBE-enhanced formulations substantially improve foam stability and fuel resistance. Full article

Food is essential for human survival; however, food can be an important route of exposure to contaminants. This study investigated the presence and distribution of anthropogenic contaminants in food consumed by families with small children in South Florida, United States, evaluating seasonal and socio-economic variabilities in chemical composition. QuEChERS protocols, followed by non-targeted analysis (NTA) using an LC-Orbitrap HRMS system, were used for the comprehensive screening of organic contaminants. The compounds were annotated and identified with the Compound Discoverer (CD) software, and contaminant distributions were analyzed using boxplots and Principal Component Analysis (PCA). The results showed significant seasonal and socio-economic differences in contaminant distributions (p < 0.05). In the wet season, a predominance of polymers and surfactants, such as dodecanedioic acid and N-dodecylacrylamide, were found in food, which might be due to increased transport of industrial pollutants during increased precipitation, while plasticizers (e.g., bis(2-ethylhexyl) phthalate) and drugs (e.g., warfarin) were more prevalent during the dry season, which could be related to less dilution effects in this period. A higher abundance of 1-nitrosopiperidine, present in cured meats, was noted in food from upper socio-economic classes, while the lower class showed higher abundance of benzocaine, a common topical anesthetic. Full article

The rational design of heterojunction photocatalysts enabling fast transportation and efficient separation of photoexcited charge carriers is the key element in visible light-driven photocatalyst systems. Herein, we develop a unique Z-scheme heterojunction consisting of NiMoO₄ microflowers (NMOF) and ZIF67, referred to as ZINM (composite), for the purpose of antibiotic degradation. ZIF67 was produced by a solution process, whereas NMOF was synthesized via coprecipitation with a glycine surfactant. The NMOF exhibited a monoclinic phase with a highly oriented, interconnected sheet-like morphology. The ZINM showed better optical and charge transfer characteristics than its constituents, ZIF67 and NiMoO₄. Consequently, the developed heterojunction photocatalysts exhibited superior photocatalytic redox capability; the ZINM30 (the composite with 30 wt.% of NiMoO₄ loaded) could degrade 91.67% of tetracycline and 86.23% of norfloxacin within 120 min. This enhanced photocatalytic activity was attributable to the reduced bandgap (E_gap = 2.01 eV), unique morphology, high specific surface area (1099.89 m²/g), and intimate contact between ZIF67 and NiMoO₄, which facilitated the establishment of the Z-scheme heterojunction. Active species trapping tests verified that •O₂⁻ and h⁺ were the primary species, supporting the proposed degradation mechanism. This work highlights a valid Z-scheme ZIF67/NiMoO₄ heterojunction system for efficient carrier separation and, therefore, enhanced photocatalytic degradation of antibiotics. Full article