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Root canal irrigants are difficult to diffuse deep into the dentinal tubules for root canal disinfection. The purpose of this study was to assess the ability of different diffusing enhancers to deliver chlorhexidine (CHX) into dentinal tubules. The diffusing property of five diffusing enhancers (acetone, DMSO, Triton X-100, JFC-E and azone) into dentinal tubules was firstly assessed using the Rhodamine B. The ability of the diffusing enhancers to deliver CHX into dentinal tubules was then evaluated both qualitatively and quantitatively. A deep dentinal tubule Enterococcus faecalis infection model was further established to test the bactericidal effect of CHX delivered by different diffusing enhancers. Finally, the in vitro cytotoxicity of these diffusing enhancers was tested using the CCK-8 method. Azone, Triton X-100 and JFC-E exhibited the largest maximum diffusing depths at all root canal parts (P < 0.05). Azone group also showed the highest percentage of diffusing depths for all root canal parts, followed by Triton X-100 (P < 0.05). The percentage of dead bacteria in dentinal tubules close to cementum layer was significantly higher in the CHX + azone group than in the other groups (P < 0.05), followed by CHX + Triton X-100 and CHX + JFC-E groups. The concentration of CHX diffusing onto the exterior surface of root was significantly higher in CHX + azone group than in the other groups (P < 0.05). All the diffusing enhancers showed relatively low cytotoxicity. Azone showed the highest diffusing ability with low cytotoxicity and might be employed as a carrier agent for either intracanal irrigants or medications to achieve more thorough root canal disinfection. [ABSTRACT FROM AUTHOR]

We provide a novel investigation that demonstrates the synthesis of silver-doped bismuth oxide (ABO), holmium-doped bismuth oxide (HBO), nanostructured bismuth oxide (BO), and silver-holmium co-doped bismuth oxide (CDBO) by a cost-effective and straightforward surfactant-assisted co-precipitation technique. In comparison to the BO, ABO, and HBO samples, the optical tests revealed that the CDBO sample exhibited superior photocatalytic characteristics. This is possibly attributed to the physical, optical, and structural properties of the material tailored by the synergistic effect of the adopted strategies, i.e., nanotechnology, oxygen vacancies, and co-doping. The microstructures, physicochemical properties, morphological characteristics, and compositional attributes of the synthesized materials were investigated using sophisticated characterization techniques. The intrinsic conductivity of the bismuth oxide was enhanced with the incorporation of Ag and Ho as co-dopants, as shown by the results obtained from two probe current-voltage experiments. The co-doped sample exhibited the highest efficacy in decomposing rhodamine B dye, with a degradation rate of 91 % during a mere 70-min exposure to W-lamp illumination. The most ideal settings for CDBO photocatalytic activities were identified by comprehensive parameter optimization research. These parameters include a basic pH, a catalyst dosage of 25 mg, a dye concentration of 15 ppm, and an operating temperature of 30 °C. The co-doped and nanostructured photocatalyst also showed an outstanding capability to break down orange II and phenol dye. The trapping experiments' results indicate that the hydroxyl and superoxide radicals play a significant role in the mineralization of the tested dye. [Display omitted] • Co-doped Bi 2 O 3 NPs have been prepared via wet route. • Synthesized samples were characterized via PXRD, FTIR, SEM, BET, and I–V studies. • Co-doping create structural defects and reduced the band gap. • Current-voltage study confirms improved current conductivity. • Co-doped Bi 2 O 3 effectively mineralized the RhB, Orange II and phenol dye. [ABSTRACT FROM AUTHOR]

This study confirms the sodium lauryl sulfate (SLS) surfactant is effective to enhance water electrolysis performance especially when combined with NaCl. The water electrolysis experiment on different concentrations of SLS and SLS-NaCl mixture electrolyte were performed. The results indicate the presence of NaCl is more effective to enhance the SLS containing electrolyte performance instead of adding more SLS concentration. More SLS concentration is effective to enhance hydrogen evolution reaction (HER) when NaCl is added. The effectiveness of NaCl is shown by the order of final HER SLS 0.5 M + NaCl 3.9212 × 10−7 Mol. L−1, SLS 0.3 M + NaCl 3.8789 × 10−7 Mol. L−1, and, SLS 0.5 M 3.6758 × 10−7 Mol. L−1. The SLS creates positively charged micelles which increases ion mobility and HER. The NaCl accelerates the HER due to the formation of smaller ion clusters that react more quickly with the cathode. Therefore, this study reveals the mechanism of electrolysis enhancement by surfactant mixed electrolyte. [Display omitted] • Sodium Lauryl Sulfate (SLS) forms positively charged micelles. • SLS enhances hydrogen evolution reaction (HER) by carry water to cathode. • NaCl ion clusters improves SLS effectiveness to improve HER. • Na ion cluster has better electrostatic response towards cathode. • Cooperation of NaCl and SLS improves overall efficiency. [ABSTRACT FROM AUTHOR]

Protein denaturation and aggregation resulting from the effects of interfacial stress, often enhanced by flow and shear stress, pose significant challenges in the production of therapeutic proteins and monoclonal antibodies. The influence of flow on protein stability is closely intertwined with interfacial effects. In this study, we have developed a microfluidic device capable of exposing low volume (< 320 µL) protein solutions to highly uniform shear. To disentangle the synergistic impact of flow and interfaces on protein aggregation, we fabricated two devices composed of different materials, namely poly(methyl methacrylate) (PMMA) and stainless steel. Upon application of shear, we observed formation of protein particles in the micron-size range. Notably, The number of particles generated in the steel devices was ∼ 3.5 fold lower than in the PMMA device, hinting at an interface-mediated effect. With increasing the protein concentration from 1 to 50 mg/mL we observed a saturation in the amount of aggregates, further confirming the key role of solid-liquid interfaces in inducing particle formation. Introduction of non-ionic surfactants prevented protein aggregation, even at the highest tested protein concentration and low surfactant concentrations of 0.05 mg/mL. Overall, our findings corroborate the synergistic impact of shear and interface effects on protein aggregation. The device developed in this study offers a small-scale platform for assessing the stability of antibody formulations throughout various stages of the development and manufacturing process. [ABSTRACT FROM AUTHOR]

Amphotericin B (AmB) is the gold standard for antifungal therapy; however, its poor solubility limits its administration via intravenous infusion. A promising formulation strategy to achieve an oral formulation is the development of amorphous solid dispersions (ASDs) via spray-drying. Inclusion of surfactants into ASDs is a newer concept, yet it offers increased dissolution opportunities when combined with a polymer (HPMCAS 912). We developed both binary ASDs (AmB:HPMCAS 912 or AmB:surfactant) and ternary ASDs (AmB:HPMCAS 912:surfactant) using a variety of surfactants to determine the optimal surfactant carbon chain length and functional group for achieving maximal AmB concentration during in vitro dissolution. The ternary ASDs containing surfactants with a carbon chain length of 14 ± 2 carbons and a sulfate functional group increased the dissolution of AmB by 90-fold compared to crystalline AmB. These same surfactants, when added to a binary ASD, however, were only able to achieve up to a 40-fold increase, alluding to a potential interaction occurring between excipients or excipient and drug. This potential interaction was supported by dynamic light scattering data, in which the ternary formulation produced a single peak at 895.2 dnm. The absence of more than one peak insinuates that all three components are interacting in some way to form a single structure, which may be preventing AmB self-aggregation, thus improving the dissolution concentration of AmB. [ABSTRACT FROM AUTHOR]

Amphiphilic peptides hold great potential as drug delivery systems. A popular peptide design approach has been to place amino acids in the peptide sequence based on their known properties. On the other hand, the directed discovery approach aims to screen a sequence space for a desired property. However, screening amphiphilic peptides for desirable drug delivery properties is not possible without a quantity that is predictive of these properties. We studied the predictive power of critical aggregation concentration (CAC) values on the drug delivery performance of a series of amphiphilic peptides with different hydrophobic tails and close CAC values. The CAC values were predicted by our previously developed model and doxorubicin was used as a model hydrophobic drug. All peptides showed close drug loading, entrapment efficiency, and release profile. They also formed similar spherical particles by assembling in reverse β -sheet arrangements regardless of drug presence. Moreover, the assembled particles were able to accumulate doxorubicin inside ordinary as well as drug-resistant breast cancer cells and enhance its toxicity up to 39 and 17 folds, respectively. It can be concluded that similar drug delivery properties displayed by the peptides can be attributed to their similar hydrophilic-lipophilic balance as reflected in their close CAC values. [Display omitted] • The designed amphiphilic peptides co-assembled with doxorubicin and decreased its IC50 in the ordinary and drug-resistant breast cancer cells up to 39 and 17 folds, respectively. • Amphiphilic peptides with different amino acids in their hydrophobic tails and close critical aggregation concentrations showed similar drug delivery performance. • Based on our results critical aggregation concentration can be an estimator of the drug delivery properties of self-assembling amphiphilic peptides. [ABSTRACT FROM AUTHOR]

Décrire l'incidence, les facteurs de risque, les facteurs associés ainsi que l'évolution à court terme de l'hémorragie pulmonaire (HP) dans une population d'extrême prématuré. Étude rétrospective cas témoin incluant 33 prématurés < 29 SA ayant présenté une HP au cours du premier mois de vie, du 1er septembre 2014 au 30 juillet 2017. Chaque enfant a été apparié à un nouveau-né, né le plus proche chronologiquement, de même sexe, même terme et même poids de naissance. Les données concernant l'évolution jusqu'à la sortie d'hospitalisation ont été collectées. Sur cette période, la prévalence de l'hémorragie pulmonaire était de 7 %. L'âge gestationnel (AG) moyen était de 25 + 0 SA, le poids de naissance moyen de 760 g, identiques dans les deux groupes. En analyse univariée, une cure incomplète de corticoïdes (< 2 doses) en anténatale (p = 0,01), le recours à l'OHF (p < 0,001), au NO (p = 0,01) et à la dopamine (p < 0,01) étaient des facteurs associés à HP. En analyse multivariée, l'absence de cure complète de corticoïdes en anténatale reste un facteur de risque de survenue d'HP (p = 0,04). Les données concernant le canal artériel ne sont pas différentes entre les 2 groupes tout comme la durée de ventilation invasive, les taux de DBP à 36 SA corrigée, d'ECUN et d'infections secondaires. Il existe une surmortalité dans le groupe HP (60,6 vs 12,1 %) avec une augmentation de la survenue des hémorragies intraventriculaire (HIV) 3 et 4, (60,6 vs 18,2 %). Dans la population des HP, les facteurs de risque associés au décès sont le sexe masculin (p < 0,01) et un pH à la naissance plus bas (p < 0,02). Un AG bas et une administration très précoce de surfactant semblent plus fréquent chez les nouveau-nés décédés sans que ces différences ne soient significatives (p = 0,06). L'hémorragie pulmonaire s'associe à une mortalité élevée dans la population des extrêmes prématurés. Une corticothérapie anténatale incomplète apparaît être un facteur de risque de survenue HP et le sexe masculin un facteur de risque de décès. To describe the incidence, associated factors and risk factors, the short-term course for the occurrence and death of pulmonary hemorrhage in the population of premature extremes. This was a retrospective case-control study involving 33 premature infants < 29 weeks who had HP during the first month of life, frome 1st september 2014 to 30th July 2017. A control was selected for each case: the closest chronologically born, child of the same gestational age, same gender and similar weight at birth. The data concerning the evolution until the discharge of hospitalization were collected. The prevalence of pulmonary hemorrhage was 7 %. Mean gestational age (GA) was 25 ± 0 weeks, the average birth weight was 760 g in both groups. In univariate analysis, an incomplete course of corticosteroids (< 2 doses) in antenatal (P = 0.01), the use of HFOV (P < 0.001), NO (P = 0.01) and dopamine (P < 0.01) were factors associated with HP. In multivariate analysis, the absence of a complete course of corticosteroids in the antenatal period remains a risk factor for the occurrence of HP (P = 0.04). The arterial duct data were not different between the 2 groups, as was the duration of invasive ventilation, bronchopulmonary dysplasia at 36 weeks corrected, necrotizing enterocolitis, and secondary infections. There is excess mortality in the HP group (60.6 vs. 12.1 %) with an increase in the occurrence of intraventricular haemorrhage ¾ (60.6 % vs. 18.2 %). In the HP population, risk factors associated with death are male (P < 0.01) and lower pH at birth (P < 0.02). Low AG and very early surfactant administration appear to be more common in deceased infants without these differences being significant (P = 0.06). Pulmonary hemorrhage is associated with high mortality in the population of premature extremes. Incomplete antenatal corticosteroids and the male sex appear to be a risk factor of death of HP. [ABSTRACT FROM AUTHOR]

This work focuses on studying the effect of Sodium Dodecyl Sulphate (SDS) at its critical micelle concentration (CMC) on the performance of ion conducting gel polymer electrolytes (GPEs) for supercapacitors. By incorporating SDS at its CMC, the morphology of GPE were altered, leading to improved ion transport properties. Additionally, SDS influenced the electrode-electrolyte interface, resulting in modifications to the charge storage mechanisms and capacitance values. The GPE exhibited a high ionic conductivity of 5.6 mS/cm. The resulting supercapacitor demonstrated exceptional performance with respect to the blank supercapacitor, including high specific capacitance, energy density, as well as low self-discharge characteristics. The specific capacitance of the supercapacitor was measured to be 18.01 Fg-1, while the energy density reached 0.362 Wh/kg. Furthermore, the supercapacitor exhibited a power density of 2.00 kW/kg. The electrolyte was analysed using impedance studies to study the effects of SDS micelles on the properties of the electrolyte film. The GPE was sandwiched between two Laser Induced Graphene (LIG) electrodes prepared from (Polyimide) PI Sheets. Cyclic Voltammetry (CV), Galvanostatic Charge-discharge (GCD), and Electrochemical Impedance Spectroscopy (EIS) was done to study the electrochemical characteristics of the supercapacitors. [Display omitted] • SDS micelles was used to improve the ion-transport of the PVA-Ammonium Acetate-based Gel-polymer electrolyte. • Presence of micelles showed an improvement in conductivity and dielectric properties. • Micelle modified electrolyte shows significant reduction in charge-transfer resistance and solution resistance. • Micelle modified electrolyte reduced self-discharge, retaining 35% of its initial voltage. [ABSTRACT FROM AUTHOR]

The fabrication of SrFe 12 O 19 ferrite powders with good magnetic properties is a key process in the industrial production of permanent magnets. Remanence and coercivity of the powders was seriously decreased due to the generation of surface lattice defects produced during the crushing of pre-sintered ferrite powders. And the traditionally applied high-temperature annealing above 800 °C can only partially restore the magnetic properties. In this work, the effects of types, adding mode and contents of surfactant (hexadecyl trimethyl ammonium bromide, triethanolamine) on the magnetic properties of crushed powders of the pre-sintered SrFe 12 O 19 ferrite under a low-temperature annealing of 400 °C process were systematically explored. The results showed that surfactants are beneficial to restore or even enhance the magnetic properties of the crushed powders compared with the pre-sintered ferrite due to the refinement of the particles and repairing the surface defects. The surfactant-assisted low-temperature annealing process proposed in this work will promote the commercial production of high performance ferrite powders and ferrite magnets, which can also effectively reduce the production energy consumption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Regeneration of waste graphite by using surfactant assisted methanesulfonic acid. • The purity and recovery rate of regenerated graphite reaches 99.7% and 98.0%. • This method can protect the graphite structure under impurity removal conditions. • Regenerated graphite exhibits excellent electrochemical performance. With the vigorous development of the new energy industry, the use of lithium-ion batteries (LIBs) is growing exponentially, and the recycling of spent LIBs has gradually become a research hotspot. Currently, recycling both cathode and anode materials of LIBs is important to environmental protection and resource recycling. This research reports a method of efficient purification and high-quality regeneration of graphite from spent LIBs by surfactant-assisted methanesulfonic acid (MSA). Under the optimal conditions (0.006 mol/L sodium dodecyl sulfonate, 0.25 mol/L MSA, 10 vol% hydrogen peroxide, liquid–solid ratio of 30:1 mL/g, 60 °C, 1.5 h), the purity of the regenerated graphite was 99.7 %, and the recovery efficiency was 98.0 %. The regenerated graphite showed the characteristics of small interplanar spacing, high degree of graphitization, a small number of surface defects, and excellent pore structure, which was closer to commercial graphite. Furthermore, the regenerated graphite electrode exhibited superior rate performance and cycling stability with a high specific capacity of 397.03 mAh/g after 50 cycles at 0.1C and a charge–discharge efficiency of 99.33 %. The recovery of anode graphite beneficial for resource utilization, environmental protection, and cost control throughout the entire production chain. [ABSTRACT FROM AUTHOR]

The development of low-cost, long-life alkaline OER catalysts with competitive precious metal activity is of great importance for the sustainable decomposition of water and the development of hydrogen energy. In this study, Mo-doped CoO x electrode CMOT (Co: Mo = 7:3+Tween20) with superhydrophilic surface structure was prepared on titanium plates by using a more industrial thermal decomposition coating method. The results showed that the addition of Mo not only adjusted the pore structure of the catalyst but also increased the oxygen vacancy level. The self-loading effect of Tween20 makes the catalyst more dispersed and granulated. It changes the particle size distribution and improves the specific surface area while increasing the wettability of the material surface and accelerating the adsorption of water molecules at the anode. When the electrode is used for anodic oxygen evolution, its oxygen evolution overpotential at 0.1 M KOH, 10 mA cm−2 is as low as 250 mV vs.RHE. Its accelerated life can be up to 304 h under severe test conditions of 1 M KOH, 1 A cm−2, 60 °C. Therefore, the CMOT electrode has excellent OER catalytic activity and stability. This study provides a new idea for developing anode materials for water electrolysis hydrogen production. • Mo doping makes the Co-based electrode show more oxygen vacancies. • Tween20 modification makes the electrode obtain superhydrophilic properties. • Stronger hydrophilicity is beneficial to improve OER performance. • The introduction of Tween20 compensates for the loss of electrode life. • At 0.1 M KOH, the η 10 mA cm-2 of the CMOT electrode is only 250 mV vs.RHE. [ABSTRACT FROM AUTHOR]

The main purpose of this research was to explore the likelihood of preparation of highly concentrated slurries of stabilized submicron CaCO 3 particles using a surfactant in a pilot-scale mixing system. To achieve this goal, the effects of independent factors such as CaCO 3 and surfactant (lecithin) concentrations, impeller type, and their interactions on power consumption, slurry rheological characteristics, and particle size were investigated. Employing the Eulerian-Granular multiphase model, a computational fluid dynamics model (CFD) was created. The validated CFD model was utilized to assess the degree of homogeneity for slurries agitated inside the mixing system. The lowest power consumption, the smallest particle size and consistency index, and the highest power-law index were achieved for highly concentrated slurries containing the optimal amount of lecithin (3.5 wt%) for the stabilization of fine CaCO 3 particles. The high-shear sawtooth impeller was shown to be the most efficient impeller for mixing fine CaCO 3 slurries containing lecithin. [Display omitted] • The optimal concentration of surfactant was found to be 3.5 wt%. • Smaller particle sizes were attained at the optimal surfactant concentration. • Use of 3.5 wt% surfactant led to the shortest mixing time and lowest power consumption. • Impeller type and surfactant concentration had a significant effect on the particle size. • Sawtooth impeller was the most efficient impeller for slurry preparation. [ABSTRACT FROM AUTHOR]

Orbital shaking in a glass vial is a commonly used forced degradation test to evaluate protein propensity for agitation-induced aggregation. Vial shaking in horizontal orientation has been widely recommended to maximize the air-liquid interface area while ensuring solution contact with the stopper. We evaluated the impact of shaking orbit diameter and frequency, and glass vial orientation (horizontal versus vertical) on the aggregation of three proteins prepared in surfactant-free formulation buffers. As soon as an orbit-specific frequency threshold was reached, an increase in turbidity was observed for the three proteins in vertical orientation only when using a 3 mm agitation orbit, and in horizontal orientation only when using a 30 mm agitation orbit. Orthogonal analyses confirmed turbidity was linked to protein aggregation. The most turbid samples had a visually more homogeneous appearance in vertical than in horizontal orientation, in line with the predicted dispersion of air and liquid phases obtained from computational fluid dynamics agitation simulations. Both shaking orbits were used to assess the performance of nonionic surfactants. We show that the propensity of a protein to aggregate in a vial agitated in horizontal or vertical orientation depends on the shaking orbit, and confirm that Brij® 58 and FM1000 prevent proteins from agitation-induced aggregation at lower concentrations than polysorbate 80. [Display omitted] • Protein propensity for aggregation in a vial agitated in horizontal or vertical orientation depends on the shaking orbit. • Computational fluid dynamics agitation simulations reflect the visual homogeneity of aggregated samples. • Brij® 58 and FM1000 prevent proteins from agitation-induced aggregation at lower concentrations than polysorbate 80. [ABSTRACT FROM AUTHOR]

MoS 2 is an attractive cost-effective replacement for Pt-catalysts in HER applications, but its usefulness is constrained by weak electrical conductivity and activity density. Herein, a low-cost highly activated carbon/molybdenum disulfide (AC/MoS 2) electrocatalyst has been developed through surfactant-assisted hydrothermal synthesis of MoS 2 nanosheets on the heteroatom-doped AC derived from green biomass source. The high surface area conductive carbon matrix was prepared through green activation of wasted petal rose flower. To provide the many active edge sites, F108 polymer was utilized to control of the well-distribution of flower-like few-layer MoS 2 nanosheets on the nanoporous conductive carbon matrix. The prepared composite demonstrated a low overpotential of 136 mV in 10 mA cm−2 with Tafel slope of 72 mV dec−1 in 0.5 M H 2 SO 4. Notably, the AC/MoS 2 construction displayed significantly lower overpotential than commercial Pt/C catalyst at the current densities higher than 410 mA cm−2. [Display omitted] • Green activation of wasted petal rose flowers to obtain the high surface area nanoporous carbon (1125 m2 g−1). • The well-distribution of few-layer MoS 2 nanosheets on the nanoporous carbon matrix. • Engineering of the MoS 2 morphology through block copolymers. • Three times lower overpotential than nickel foam substrate. • Lower overpotential than commercial Pt/C catalyst at the high current densities (≥410 mA cm−2). [ABSTRACT FROM AUTHOR]

Surfactant protein A (SP-A), a natural immune molecule, plays an important role in lung health. SP-A recognizes and binds microbial surface glycogroups through the C-type carbohydrate recognition domain, and then binds corresponding cell surface receptors (such as C1qRp, CRT-CD91 complex, CD14, SP-R210, Toll-like receptor, SIRP-α, CR3, etc.) through collagen-like region, and subsequently mediates biological effects. SP-A regulates lung innate immunity by promoting surfactant absorption by alveolar type II epithelial cells and phagocytosis of pathogenic microorganisms by alveolar macrophages. SP-A also regulates lung adaptive immunity by inhibiting DC maturation, and T cell proliferation and differentiation. This article reviews latest relationships between SP-A and adaptive and intrinsic immunity. • This review provides the first comprehensive account of the role of SP-A in both intrinsic and adaptive immunity. • Comprehensive and detailed description of the molecular structure of SP-A, receptor levels, etc. • Pointing out the lack of research on SP-A in adaptive immunity. [ABSTRACT FROM AUTHOR]

Hydrogen is increasingly recognized as the most significant alternative solution for reducing global greenhouse gas emissions in maritime transportation. In particular, solid-state sodium borohydride (NaBH 4) with its high hydrogen storage density stands out as the preferred choice due to its higher efficiency and improved safety. In present study, a surfactant-stabilized CoB catalyst was used in order to improve the hydrolysis performance of NaBH 4. For this reason, the effects of Triton X-100, used as a surfactant in different quantities, on the hydrogen generation rate were tested. To characterize the prepared samples, several analytical techniques were employed, including field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), Mastersizer analysis, X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) analysis. According to findings, 40.2% faster hydrogen generation rate is obtained with CoB-Triton 150 contrary to CoB catalyst. The optimum concentrations are found as 5% NaOH and 5% NaBH 4 and activation energy is 44.21 kj/mol for developed CoB-Triton 150 catalyst. Last of all, fuel cell performances show that the produced hydrogen from hydrolysis reaction through CoB-Triton 150 catalyst has nearly same fuel cell performance compared to industrial pure hydrogen. Consequently, Triton X-100 is a good candidate to improve the hydrolysis performance of NaBH 4 and needs further research. • Use of Triton X-100 surfactant during chemical reduction of CoB catalyst. • 150 μl Triton X-100 use increases HGR 40.2%. • Activation energy of the CoB-T150 is 44.21 kj/mol. • Triton X-100 is a good alternative with easily implementation. [ABSTRACT FROM AUTHOR]

This study highlights the promising potential of utilizing an MFC reactor equipped with Nafion 117 and PVA/GA membranes. This innovative and cost-effective approach has proven to be highly effective in addressing the challenge of treating methyl tertiary butyl ether (MTBE) in wastewater, while also offering the added benefit of electricity generation. Biodegradation efficiency and electricity generation were assessed in this study using co-substrates such as glucose (GLS) and sodium acetate (SAC), in addition to surfactants like sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB). The MTBE concentration ranged from 10 to 200 mg/L, and it was quantified in the samples through gas chromatography with a flame ionization detector (GC–FID). To explore the structural characteristics of Nafion 117 and PVA/GA membranes, we conducted field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) analyses. The maximum biodegradation efficiency of MTBE (%) in MFC reactors with Nafion 117 and PVA/GA membranes was found to be 93.3% and 89.8%, accompanied by maximum production voltages (mV) of 895 mV and 853 mV, respectively. This was achieved with the addition of SAC co-substrate and SDS surfactant. Notably, the addition of co-substrate had a more significant impact compared to the surfactant. Simultaneously adding both the co-substrate and surfactant had a substantial effect on both the biodegradation efficiency (%) of MTBE and the generated voltage. Based on these findings, it can be concluded that the MFC reactor equipped with Nafion 117 and PVA/GA membranes is capable of effectively breaking down MTBE. However, due to its lower cost, the PVA/GA membrane may be considered a more economical choice. Therefore, the utilization of an MFC reactor featuring Nafion 117 and PVA/GA membranes holds great promise as an efficient approach for treating MTBE in wastewater, while concurrently generating electricity. [Display omitted] • The process of MTBE biodegradation was examined in a 2-part MFC reactor. • Proton exchange membranes showed similar efficiency, but different voltage generation. • The addition of co-substrate and surfactant improved efficiency and voltage generation. • Simultaneously adding SAC co-substrate and SDS surfactant led to the best results. • The MFC reactor performed well in both MTBE biodegradation and voltage generation. [ABSTRACT FROM AUTHOR]

This study investigated the novel method of ammonia use in a light-duty automotive diesel engine. An emulsification technique and ammonia solution are combined and adopted to prepare ammonia solution in diesel emulsion referred to as emulsified diesel-ammonia solution (EDAS) and tested under similar diesel combustion conditions. The ammonia solution concentration in EDAS was fixed as 10% by volume (EDAS10) with 2% v/v of surfactant to avoid excessive ammonia slip, corrosive effects, and oxides of nitrogen (NOx) formation. The aim of this study is to explore the effect of presence of hydrogen in EDAS10 on the diesel combustion process under high-pressure multiple injection strategies. Experiments were performed at low, medium, and high loads at the same combustion phasing (CA50) and total energy input as that of diesel to investigate the influence of EDAS10 on combustion, performance, and emissions. The start of injection of EDAS10 and exhaust gas recirculation rate was varied to attain the CA50. The combustion results showed that the EDAS10 blend had increased the heat release rate in the premixed combustion phase with shortened duration and decreased the heat release rate in the diffusion combustion phase compared to neat diesel operation. Double and triple injection of EDAS10 blend also increased the indicated and brake thermal efficiencies by about 4–7% than neat diesel operation. A decrease in 50–67% unburnt emissions, 8–13% decrease in smoke, and 7–19% increase in NO emissions, 2–10% increase in CO 2 emissions were observed with EDAS10 when compared to diesel operation. • Ammonia solution in diesel emulsion could be an innovative option for use of ammonia in automotive diesel engine. • Ammonia solution concentration is fixed as 10% to tackle excessive ammonia slip, corrosive effects, and NOx formation. • EDAS10 blend has increased the brake thermal efficiency. • Hydrogen in EDAS10 played a significant role in combustion. • EDAS10 operation decreased unburnt/smoke emissions and slightly increased NO emissions. [ABSTRACT FROM AUTHOR]

Extensive studies have been conducted on the efficacy of vegetable oils as surfactant feedstocks for enhanced oil recovery. This has become necessary owing to environmental concerns and high costs of synthetic surfactants. In this review, three stages of screening criteria for vegetable seeds and oils as surfactant feedstock have been identified. The first stage involves the selection of vegetable seeds and peels that are agro-waste, non-edible, abundant, and biodegradable; the second stage considers the physicochemical properties of vegetable oils, especially those with long chain monounsaturated fatty acids; and the third stage considers surface-active properties, thermal stability, oxidative stability, and oil-recovery efficiency of vegetable oil-based surfactants. Previous findings suggest that vegetable oil-based surfactants that have high fractions of long chain monounsaturated fatty acids have good surface-active properties, while those with saturated fatty acids have thermal and oxidative stabilities. Despite these findings, current research works have largely ignored vegetable seeds and oils that satisfy the screening criteria elucidated in this review. Consequently, the physicochemical properties of vegetable seeds and oils that have been ignored as surfactant feedstocks are reviewed. Challenges of the use of vegetable oils as surfactant feedstocks and possible remediation strategies are presented. • Vegetable oils that are utilized and those yet to be utilized as surfactant feedstock are reviewed. • Stability of vegetable oil-based surfactants is influenced by the fatty acid composition. • Pawpaw seed oil is a potential surfactant feedstock. • Vegetable oil-based surfactants are yet to be applied on the field. [ABSTRACT FROM AUTHOR]

As a growing number of protein drug products are developed, formulation characterization is becoming important. An IgG drug product is tested at concentrations from 0.0001–0.1 mg/mL for adsorption behavior to polymer surfaces polyvinyl chloride (PVC) and polypropylene (PP) upon dilution in normal saline (NS) using quartz crystal microbalance with dissipation (QCM-D). The studies mimicked IgG antibody interaction during IV administration with polymeric surfaces within syringes, lines, and bags. Drug product was characterized with excipients, with focus on surfactant. Drug solutions were run over polymer-coated sensors to measure the adsorption behavior of the formulation with emphasis on the behavior of each of the formulation's components. Over 60 sensorgram data sets were correlated with assayed protein solution concentrations in mock NS-diluted infusions of drug product in the equivalent concentrations to QCM experiments to build a preliminary predictive model for determining fraction of drug and surfactant adsorbed and lost at the hydrophobic surface during administration. These results create a method for reliably and predictively estimating drug product adsorption behavior and protein drug dose loss on polymers at different protein drug concentrations. [ABSTRACT FROM AUTHOR]

Therapeutic proteins and antibodies are exposed to a variety of interfaces during their lifecycle, which can compromise their stability. Formulations, including surfactants, must be carefully optimized to improve interfacial stability against all types of surfaces. Here we apply a nanoparticle-based approach to evaluate the instability of four antibody drugs against different solid-liquid interfaces characterized by different degrees of hydrophobicity. We considered a model hydrophobic material as well as cycloolefin-copolymer (COC) and cellulose, which represent some of the common solid-liquid interfaces encountered during drug production, storage, and delivery. We assess the protective effect of polysorbate 20, polysorbate 80, Poloxamer 188 and Brij 35 in our assay and in a traditional agitation study. While all nonionic surfactants stabilize antibodies against the air-water interface, none of them can protect against hydrophilic charged cellulose. Polysorbates and Brij increase antibody stability in the presence of COC and the model hydrophobic interface, although to a lesser extent compared to the air-water interface, while Poloxamer 188 has a negligible stabilizing effect against these interfaces. These results highlight the challenge of fully protecting antibodies against all types of solid-liquid interfaces with traditional surfactants. In this context, our high-throughput nanoparticle-based approach can complement traditional shaking assays and assist in formulation design to ensure protein stability not only at air-water interfaces, but also at relevant solid-liquid interfaces encountered during the product lifecycle. [Display omitted] [ABSTRACT FROM AUTHOR]

Polysorbate 80 (PS80), a chemical substance composed of sorbitol, ethylene glycol, and fatty acids, is commonly used in pharmaceutical drug products to stabilize formulations. However, recent studies have demonstrated that PS80 may hydrolyze over time and the released free fatty acids (FFAs) may lead to particle formation. Naming conventions of fatty acids in current pharmacopeia and in products' certificates of analysis (CoA) of PS80 do not typically distinguish between isomeric species of fatty acids in PS80. Thus, methods to fully characterize the fatty acid species present in PS80 raw materials are needed to enhance quality control strategies of pharmaceuticals using PS80. Here, extended effort is taken to characterize fatty acids in hydrolyzed PS80 raw materials and elucidate the identities of isomeric fatty acid species. In this work, a method was developed and optimized for separation and detection of fatty acids in alkaline hydrolyzed PS80 raw materials using ultra performance liquid chromatography (UPLC) with ultra-violet (UV) detection and evaporative light scattering detection (ELSD). Fatty acids not specified in the current pharmacopeias were detected in PS80 raw material by the developed LC-UV-ELSD method including conjugated forms of linoleic and linolenic fatty acid species. Their identities were orthogonally confirmed by retention time agreement with analytical standards, accurate mass by high resolution mass spectrometry, UV absorbance, and proton nuclear magnetic resonance spectroscopy. The detected conjugated fatty acids are theoretically more hydrophobic and less soluble than their unconjugated counterparts and may increase the propensity of PS80 to form particles upon hydrolysis. This work highlights the need for better quality control of PS80 raw material, as it may eventually play a critical role in product quality of therapeutic proteins. [ABSTRACT FROM AUTHOR]

Iron-chromium/SBA-15 (Fe–Cr/SBA-15) catalysts for high-temperature water-gas shift reactions (HTS) were prepared using the surfactant-assisted melt-infiltration (SAMI) method. The SAMI method was used to synthesize an efficient catalyst that could simultaneously achieve high dispersion and loading (Fe: 40 wt% and Cr/Fe molar ratio: 0.25) without a liquid solution. According to X-ray diffraction (XRD) and transmission electron microscopy analyses, it was observed that the Span60 surfactant enhanced Fe 3 O 4 particle dispersion. N 2 adsorption-desorption analysis indicated that the Fe 3 O 4 and chromium oxide particles were thoroughly infiltrated inside the mesopores of the SBA-15 support. XRD and temperature-programmed-reduction analyses revealed that the well-dispersed Fe 3 O 4 acted as active sites for the HTS reaction when Span60 was added to the Fe–Cr catalyst. In other words, the Fe–Cr catalyst synthesized via SAMI exhibited better performance and stability for the HTS reaction than that prepared without the surfactant. [Display omitted] • Fe–Cr Catalysts were synthesized via surfactant-assisted melt infiltration. • Span60, non-ionic surfactant, promoted the strong metal-support interaction. • Strong interaction facilitated filling the pores of the support with metal particles. • Highly dispersed metal particles improved the catalytic activity. [ABSTRACT FROM AUTHOR]

Crude oil production has considerably stabilized economic growth on a global scale. Unfortunately, the difficulties of oil production from a reservoir is being a global concern. Enhanced oil recovery (EOR) is one of the methods employed recently to increase oil production rate. Nanotechnology has been identified as one of the effective EOR techniques employed using nanoparticles (NPs) as a suitable candidates. Altering a reservoir's petrophysical property such as reducing interfacial tension (IFT) between crude oil and other liquids is an essential factor that plays a significant role in EOR. Considering the significant effects shown by silicon dioxide (SiO 2) and iron dioxide (Fe 2 O 3) NPs in EOR, the present study is aimed at investigating the influence of Fe 2 O 3 -SiO 2 hybrid NPs supported with a surfactant on IFT. The hybrid NPs were produced and separately incorporated with surfactants of anionic sodium dodecylbenzene sulfonate (SDBS) and polyvinylpyrrolidone (PVP). The physical and chemical properties of the hybrid NPs were analyzed using X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) spectroscopies, respectively. According to the results, the XRD pattern of the Fe 2 O 3 -SiO 2 hybrid NPs displayed a crystalline structure of Fe 2 O 3 NPs. The FTIR spectra of Fe 2 O 3 -SiO 2 hybrid NPs showed characteristic absorptions of Fe 2 O 3 and SiO 2 , indicating successful hybrid formation. The viscosity of Fe 2 O 3 -SiO 2 nanofluids has increased from 0.95 to 1.85 cP. Upon introducing a hybrid nano-surface of SDBS and PVP, the viscosity values increased to 1.95 cP and 1.90 cP, respectively. Moreover, the Fe 2 O 3 -SiO 2 hybrid NPs has reduced oil/brine/nanofluids IFT from 17.39 mN m−1 to 5.03 mN m−1. Additional reductions were observed when the surfactants were included. Consequently, IFT (mN m−1) was reduced from 17.39 to 3.08 for Fe 2 O 3 -SiO 2 -PVP and from 17.39 to 2.55 for Fe 2 O 3 -SiO 2 -SDBS. The finding of this study can help for a better understanding of the significant effect of silica-based hybrid nano-surfactant for IFT reduction which in turn could enhance oil production. • The interfacial tension (IFT) effect of Fe 2 O 3 -SiO 2 hybrid nano-surfactant was investigated. • The Fe 2 O 3 -SiO 2 hybrid nanomaterial has enhanced IFT reduction better than their respective constituents. • The IFT reduction trend of Fe 2 O 3 -SiO 2 nanofluids was improved when surfactants were incorporated. • Fe 2 O 3 -SiO 2 enhances aggregations of the nanoparticles at the oil/water interface, which facilitates IFT reduction. [ABSTRACT FROM AUTHOR]

Dust control has always been a difficult problem in the process of safe mining. Using composite surfactants becomes a simple and effective dust suppression method. However, the micro mechanism of the effect of composite ratio on coal wettability was still unclear. In this study, the experimental combined with molecular dynamics (MD) simulations were used to research the effect of different composite ratios of SDS (Sodium dodecyl sulfate)/JFC (Fatty alcohol polyoxyethylene ether) surfactant on bituminous coal wettability. The experiment results showed that the mixed JFC and SDS solution had good wettability on bituminous coal. The contact angle and surface tension decreased as the proportion of JFC increased in the compound solution. Zeta potential experiment results indicated that adding JFC improved the aggregation ability between coal dust and promoted the settlement of coal dust in the mixed surfactant. The best synergistic wetting effect was achieved at a molar ratio of 1:3 (SDS/JFC). The simulation results showed that the thickest coal/water adsorption layer was formed at a 1:3 (SDS/JFC) mixing ratio. At this ratio, the diffusion coefficients of water molecules increased significantly, which promote the probability of coal collision with water molecules. Finally, the mechanism of the optimal synergistic ratio promoting coal wetting was explained by analyzing the distribution configuration of surfactant molecules. The whole work is of great significance to coal dust prevention and provides a new idea for exploring the synergistic composite ratio of wetting agents. [Display omitted] [ABSTRACT FROM AUTHOR]

Rutin (RUT) is a phytochemical flavonoid with numerous therapeutic potentials including antihypertension, cardioprotective, neuroprotective, and anti-cancer activities. Its clinical use is inhibited due to its poor aqueous solubility and permeability over oral administration. The present study aimed to overcome these problems through micellization and entrapment of RUT in solid dispersion (SD) using Poloxamer (POL) 407 and 188 as surfactant-based matrices. The RUT/SD formulations were prepared in serial drug loading concentrations in weight percentage to the total solid. The physical properties of the formed RUT/SD solids were characterized by several methods including polarizing microscopy, differential thermal analysis (DTA), X-ray diffractometry (XRD), scanning electron microscopy (SEM) and dissolution study. The dissolution test was performed using a paddle dissolution apparatus and samples were analyzed using UV spectrophotometry. Polarized microscope confirmed that the optical behaviors of the RUT/SD implied a formation of miscible RUT with POL matrices. The morphology of RUT/SDs varied from porous matrices with craters to smoother surfaces as a function of RUT concentrations. XRD and DTA data exhibited that RUT existed as partially amorphous. These data indicated that the higher concentration of RUT in the RUT/SD formulations, the higher amorphous proportion of the RUT in the solid state. Henceforth, this led to an increase in the percentage of dissolved RUT from the developed RUT/SD formulations at 94 to 100% compared to pure RUT at only < 35% within an hour. The present study disclosed the successful improvements in the physical characteristics of the RUT/SD formulations and their potencies for the future development for oral formulation. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) printing based on digital light processing (DLP), for its great advantage in dealing with material and structural complexities, is being engaged for the fabrication of custom-designed silica optical fibre preforms. Resin preparation and printing are key processes critical to DLP fabrication of optical fibre preforms with high silica loading. In this work, the surfactant effect on preparation of resin and DLP printing of optical fibre preforms for higher silica loading is investigated. Based on our experimental studies of the rheological and photocuring properties of resins and the quality of printed silica fibre preforms, we find that, in the case where 2-phenoxyethanol (POE) is usually added as the surfactant, the resin has higher viscosity and results in poorer preform quality. By removing POE from resin ingredients and designing a multi-step resin processing with appropriate settling and degassing processes, fibre preforms with high silica loading up to 0.8 (w/w) have been successfully fabricated. [ABSTRACT FROM AUTHOR]

In the field of water treatment, the treatment of wastewater containing surfactants has been an important issue. The foam separation technique is often used to separate surfactants from water as a simple and efficient separation technique. We used a newly designed foam separation column to treat wastewater containing sodium dodecyl sulfonate (SDS) (0.5–2.0 mmol/L). The effects of initial SDS concentration (C SDS, i), operation time (t), foam height (H), gas velocity (V) and pH value (1−7) on the separation effect of SDS were investigated. The Box-Behnken design model was used to design the experimental group, and the process parameters of foam separation were optimized by combining response surface methodology (RSM) and WOA-BP neural network. The results showed that the prediction accuracy of the optimized BP neural network using the WOA algorithm was superior to that of the RSM model. The best operating parameters were: C SDS,i (0.88 mmol/L), t (28.13 min), H (81.3 cm), V (1.03 L/min) and pH (3.5) and the recovery rate of SDS was up to 97.32%. [Display omitted] • This article provides an efficient and environmentally friendly treatment process for the treatment of production wastewater containing anionic surfactants. • Response surface experimental designs were used to obtain optimal process conditions. A five-factor, three-level experimental set was designed using the Box-Behnken design (BBD) model. • The WOA-BP artificial neural network was used to analyze the experimental data to find the optimal process conditions and compare them with the RSM experimental results. [ABSTRACT FROM AUTHOR]

Enzymatic hydrolysis of polysorbate in drug products is a major challenge for the biopharmaceutical industry. Polysorbate hydrolysis caused by host cell proteins (HCPs) co-purified during bioprocessing can reduce the protective effects of the surfactant for the active pharmaceutical ingredient and cause the accumulation of low-solubility degradation products over the long-term storage. The identities of such HCPs are elusive due to their extremely low concentrations after the efficient purification processes of most biopharmaceuticals. In this work, 20 enzymes—selected for their known or putative hydrolytic activity and potential to degrade polysorbate—were recombinantly expressed, purified, and characterized via orthogonal methods. First, these recombinant HCPs were assessed for hydrolytic activity against a fluorogenic esterase substrate in a recently-developed, high-throughput assay. Second, these HCPs were screened for hydrolytic activity against polysorbate in a representative mAb formulation. Third, HCPs that displayed hydrolytic activities in the first two assays were subjected to more detailed characterization of their enzyme kinetics against polysorbates. Finally, these HCPs were evaluated for substrate specificity towards different sub-species of polysorbates. This work provides critical new insights for targeted LC-MS/MS approaches for identification of relevant polysorbate-degrading enzymes and supports improvements to remove such HCPs, including knockouts or targeted removal during purification. [ABSTRACT FROM AUTHOR]

Recently, serious attention to the high potential of nanotechnology in the enhanced oil recovery (EOR) processes have been attracted. In this study, the effects of addition of SiO 2 nanoparticle into the aqueous solutions containing octyl phenol ethoxylate (Triton-x100), sodium lauryl sulfate (SLS), and octyl pyridinium chloride ([C 8 Pyr][Cl]) on the interfacial tension (IFT) reduction, wettability alteration of carbonate rock, and the spreading coefficient were investigated. EDX and FeSEM analysis were taken on the rock that indicate the dolomite nature of the rock sample. The equilibrium IFT and contact angle values of different cases were measured in two series (i.e. with and without SiO 2 nanoparticles). It is found that the performance of SiO 2 nanoparticle remarkably affected by surfactants type and their combination. SiO 2 could not have a positive effect on the IFT reduction and wettability alteration and had an adverse effect on the performance of some surfactants. In more details, SiO 2 nanoparticles was able to slightly improve the TiO 2 surfactant performance by falling the IFT value from 2.8 to 1.5 mN/m, while it did not have a significant effect on the performance of Pyr surfactant by changing the IFT value from 14 to 13.3 mN/m. The performance order of IFT reduction and wettability alteration was completely different as the lowest IFT and contact angle values were observed for the SLS in the presence of SiO 2 (IFT reduction from 0.36 to 0.1 mN/.m) and Tr in the absence of SiO 2 (wettability change from 49º to 32.5º), respectively. However, SiO 2 nanoparticles have a favorable effect on the spreading coefficient of SLS, Pyr, SLS+Pyr, and SW; among them, the best performance was observed for SLS with spreading coefficient (Sc) value of − 0.06 mN/m. [Display omitted] • Synergistic study of SiO 2 nanoparticle with different surfactants. • SiO 2 could improve the performance of SLS anionic surfactant. • SiO 2 reduced the ability of Tr surfactant to change rock wettability. • Investigating key factors to reduce IFT and rock wettability alteration in nanoparticle/surfactant system. [ABSTRACT FROM AUTHOR]

Super alloys like Inconel 617 are extensively used in aerospace, gas turbines, chemical and food processing industry but it is extremely hard to machine from traditional methods and thereof non-traditional machining is usually engaged. Electric discharge machining (EDM) is good choice in this context as it is widely utilized in the industry for precision machining and making complex geometrical shapes in hard-to-cut materials. However, the intrinsic issues of low machining rate (MRR), dimensional overcuts and surface roughness (SR) limit its application. Therefore, the potentiality of the modified dielectric with nano powder and surfactant in aforementioned context was studied using three copper, brass and graphite as electrodes in EDM of Inconel 617. Taguchi L18 orthogonal array was used for experimentation considering nano powder type, powder concentration, surfactant type, surfactant concentration, dielectric type, electrode material and pulse time ratio as control variables. Results revealed that the addition of nano-alumina powder has proved to be the better choice in contrast to SiC for achieving high MRR. It has been noticed that average MRR found for alumina experiments was 33% more than that found with SiC. However, for SR and overcut the supremacy of SiC has been witnessed. Increase in powder concentration from 0.25 g/l to 0.625 g/l results in average increase of 15% in MRR. Whereas in case of SR, 7.5% increment is noticed as the powder concentration is raised from its 1st to 2nd level. In terms of surfactant, MRR provided by the S-80 based dielectric is 13% and 2.2% higher than that achieved with Tween-20 and Span-20 respectively. For the SR perspective, span 20 performs better than T-20 and S-80. Nevertheless, T-20 has found to the best choice for the attainment of better dimensional accuracy. The electrode of Cu provides highest MRR and minimum overcut whereas for SR, graphite electrode shows best results. The developed optimal settings confirm an improvement of 20.6%, 13.9% and 34% in the magnitudes of MRR, SR and overcut respectively during confirmation trials. Furthermore, multi-objective optimization has also been carried out for simultaneous optimization of responses. [ABSTRACT FROM AUTHOR]

The effects of surfactants on the motion and deformation of sinking and rising drops are studied numerically by employing the arbitrary Lagrangian-Eulerian (ALE) method. To describe the surfactant transfer in two-phase flow, the transport equations of the surfactant in the bulk fluid and the interface are solved in a coupled way which was developed in the commercial solver. The applicability of the numerical approach is verified by a series of benchmark tests and then employed to simulate the sinking drop contaminated by insoluble surfactant. The predicted drop motions and velocity profiles show good agreement with the experimental results from the literature, and the "stagnant cap" is found in the rear region, where the surface velocity nearly vanishes. Furthermore, the effects of the soluble surfactant on the drop rising in a straight tube are studied in detail, and the numerical results also agree well with the experimental data. It is found that the surfactant at the interface leads to the decrease of terminal velocity, especially in the transition region of drop shape. In addition, the Marangoni stress would inhibit the inner circulation of the drop and leads to immobilized behavior at the interface. The present method exhibits good accuracy and affordability, which can be easily used to solve the two-phase flow with surfactant. • Two-phase flow with surfactant is numerically studied using ALE method. • Advection-diffusion equation for surfactant is derived and solved in its weak form. • Numerical approach is validated by benchmark tests and presents good performance. • The Marangoni stress and the reduction of surface tension are two main factors affecting the drop behavior. [ABSTRACT FROM AUTHOR]

Visible particles (VPs) formation in liquid monoclonal antibody formulations is a critical quality issue. Formulations that include poloxamer 188 (PX188) as a surfactant are prone to the formation of VPs comprising aggregated complexes of protein and polydimethylsiloxane (PDMS; silicone oil) derived from primary containers. However, the mechanisms through which these VPs form are complicated and remain to be fully elucidated. This study demonstrates for the first time the dominant spot and pathway of protein–PDMS VP formation in a particular liquid vial formulation. Specifically, when a vial sealed with a PDMS-coated stopper is stored in an upright position under conditions whereby the antibody solution has become well-adhered to the stopper and an air phase exists in the vicinity, protein–PDMS aggregates form on the stopper and are then desorbed into the drug solution to be detected as VPs. Here, we evaluated the effects of several factors on VP formation: adhesion of the drug solution to the stopper, storage orientation, silicone coating on the stopper, vial material, and hydrophobicity of PX188. Remarkably, we found that changing any one of the factors could significantly affect VP formation. Our findings are instructive for better understanding the mechanisms of VP formation in vial products and can provide strategies for VP mitigation in biotherapeutics. [ABSTRACT FROM AUTHOR]

Recently, rare earth (RE) elements and their oxides have been attracting more and more attention in the field of photocatalytic degradation. Due to the unique 4 f electronic structure and optical properties, the RE element, europium (Eu), together with its oxides, are often used for surface modification of other photocatalysts. Nevertheless, the photocatalytic degradation property of europium oxide has been rarely reported. In this study, we synthesized Eu 2 O 3 nanoparticles via chemical precipitation and calcination processes, and performed surface modification by using surfactants as polyvinyl pyrrolidone (PVP) and hexadecyl trimethyl ammonium bromide (CTAB). Compared with pure Eu 2 O 3 nanoparticles and those synthesized with PVP, photocatalytic degradation efficiencies of Eu 2 O 3 nanoparticles synthesized with surfactant CTAB for degrading rhodamine B dye demonstrated to be improved by 16% and 12%, respectively. The ultraviolet-visible diffuse reflectance spectra measurements indicate that CTAB can increase the bandgap of Eu 2 O 3 due to the reduction of oxygen defects. Photoluminescence spectra demonstrate that the surfactant would affect the luminescence of Eu3+ and carrier redistribution of energy levels. [ABSTRACT FROM AUTHOR]

This article summarizes the anatomical features of the lungs, airway and thorax pertinent to the physiology of breathing and discusses chemoreceptor detection mechanisms, brainstem centres and relays involved in the control of breathing. We will discuss lung mechanics including spirometry, lung compliance, airway resistance and the role of surfactant and consider how these can be affected by disease states. It is recommended to revise principles of arterial blood gas analysis in addition to this article. [ABSTRACT FROM AUTHOR]

Herein, we have investigated the association behavior of bovine serum albumin (BSA) and cetyltrimethylammonium bromide (CTAB) using the conductivity method in H 2 O and H 2 O + organic mixed solvents at different temperatures. The association phenomenon was detected from the deviation of the conductivity changes with enhancing the surfactant concentration and changes of numerous physico-chemical properties, such as CMC , α , β and thermodynamic variables (∆ G 0 m , ∆ H 0 m and ∆ S 0 m). The values of CMC for the CTAB + BSA system in 10 % (v/v) solvents follow the trend: CMC water < CMC water+DMSO < CMC water+AN < CMC water+DX < CMC water+DMF. The interaction of BSA with CTAB is notably influenced due to a change of temperature and extent of hydration of BSA and surfactant. The obtained values of –∆ G 0 m manifest that the association of BSA and CTAB mixture is a spontaneous process, while the values of –∆ G 0 m in presence of 10 % (v/v) aq. organic solvents come out in the given sequence: -∆ G m o (H 2 O + DMSO) > ∆ G m o (H 2 O + DMF) > -∆ G m o (H 2 O + DX) > -∆ G m o (H 2 O + AN). The H-bonding, ion-dipole, along with the hydrophobic interactions, are believed to be the binding interactions between BSA and CTAB in the study media. [ABSTRACT FROM AUTHOR]

We developed a simple two-dimensional/two-components theoretical model that describes the structure and functionality of a VitE-TPGS system of micelles assuming a hydrophobic inner core and an outer hydrated hydrophilic shell. We then conceptually applied the developed methodology to a simple system of VitE-TPGS micelles unloaded and loaded with an active pharmaceutical ingredient, eltrombopag, to verify if the model could reliably monitor the size change of the micelle upon loading. The fit of laboratory Small Angle X-Ray Scattering data against such model allows us to extract absolute values of the micelles size under a spherical shape hypothesis as well as the distribution within the system between components and level of hydration. The intensity scale of the SAXS experimental data needs to be normalized to a reference standard (pure water) to get absolute scattered intensities. The mathematical model which has been developed under a general hypothesis of ellipsoidal micelles, is applied to our experimental data under the simplified spherical assumption, which suitably fits our experimental data. [ABSTRACT FROM AUTHOR]

Respiratory distress syndrome (RDS) is characterized by a lack of lung surfactant; therefore, biochemical evidence of surfactant deficiency is needed to diagnose RDS. European guidelines recommend surfactant administration when patients need fraction of inspired oxygen exceeding 0.3 on continuous positive airway pressure or intubation. We hypothesized that the European guidelines for surfactant administration were not adopted in Japan because of the lack of RDS diagnosis. This study aimed to investigate neonatologists' attitudes and practices regarding the diagnosis and management of RDS in Japan. A mail-based survey regarding the diagnosis and management of RDS was conducted at 111 level III or ΙV neonatal intensive care units in Japan. The questionnaire was completed by the person in charge of each unit. The overall response rate for the questionnaire was 91% (101/111 centers). All respondents referred to chest radiography, and the majority (83%) of respondents referred to stable microbubble rating (SMR) for establishing the diagnosis of RDS. Surfactant administration was chiefly based on clinical conditions, chest radiography, and/or SMR. Most units in Japan do not adopt the European criteria for surfactant administration. In Japan, chest radiography and/or SMR are commonly used for the diagnosis of RDS and as the rationale for surfactant administration. Further studies from other countries are required to establish the ideal criteria for surfactant administration. [ABSTRACT FROM AUTHOR]

Several outbreaks of Listeria monocytogenes originated mainly from contaminated contact surfaces. Thus, this study investigated the antilisterial effect of natural surfactants in terms of their use as a 2-in-1 sanitizing washer on a food contact surface and evaluated their modes of action. The antilisterial activity of alkyl polyglycosides (APGs), namely capryl glucoside (CA), coco glucoside (CG), and decyl glucoside (DG), was evaluated based on the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) using broth dilution assay. The results showed that CG had the strongest antilisterial activity. Therefore, CG was selected for further investigation. The time-kill assay showed a lethal effect of 0.5 % (w/w) CG by inactivating 4 Log reduction (99.99 %) of L. monocytogenes within 3 s. Furthermore, 1 % (w/w) CG with slight mechanical force in washing (by shaking) was efficient for sanitizing a stainless-steel coupon surface based on its ability to cause a total reduction of deposited L. monocytogenes (99.9 %) within 10 min. Scanning electron microscopy and applying Fourier-transform infrared spectroscopy revealed that CG chemically disrupted the cell wall and plasma membrane of L. monocytogenes within 5 min after a gentle wash. The results showed it had potent antimicrobial activity and was bactericidal against L. monocytogenes. Overall, our results supported the use of CG as a natural antibacterial surfactant to alter the chemical sanitizer and the possibility of its practical use in the food industry and for household use. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, in order to solve the application problems of poor water solubility and low bioavailability of quercetin, we prepared a nano-delivery system with core-shell structure by anti-solvent method, including a hydrophilic shell composed of tea saponin and a hydrophobic core composed of Zein, which was used to improve the delivery efficiency and biological activity of quercetin. Through the optimal experiments, the loading rate and encapsulation rate of nanoparticles reached 89.41 % and 7.94 % respectively. And the water solubility of quercetin is improved by 30.16 times. At the same time, the quercetin acted with Zein through non-covalent interaction and destroyed its spatial network through structural characterization, while tea saponin covered the surface of Zein through electrostatic interaction, making it change into amorphous state. In addition, the addition of tea saponin makes the nanoparticles remain stable under the changes of external environment. During simulating gastrointestinal digestion procedure, ZQTNPs has higher release rate and bioavailability than free quercetin. Importantly, ZQTNPs can overcome the limitations of a single substance through synergy. These results will promote the innovative development of quercetin precision nutrition delivery system. [ABSTRACT FROM AUTHOR]

Prometheus stole fire for mankind, but tungsten brought light to mankind. Wolframite is beneficiated through froth flotation and used as a raw material to produce tungsten. However, the flotation of wolframite using the surfactants as the collector at low temperature is still one of the most significant problems in industry. In this paper, a novel hydroxamic acid surfactant dodecanediohydroxamic acid (DHA) was synthesized and firstly used in wolframite ore flotation, which was compared with the conventional monomolecular collector sodium oleate (NaOL). The results of flotation test indicated that the changes of the temperature did not significantly influence DHA's collecting power in floating wolframite. At 0 °C, wolframite concentrate with WO 3 recovery of 83.65 % and grade of 55.25 % was obtained by using 200 g/t DHA. Density functional theory (DFT) calculations suggested reactive sites of DHA were two –C(O)NHOH groups, and DHA showed superior electron-donating ability and chemical reactivity that may promote its flotation performance. [Display omitted] • Dodecanediohydroxamic acid DHA was prepared and introduced in wolframite flotation. • The adsorption mechanism of DHA on the surface of wolframite was studied. • DHA exhibited excellent flotation performance for wolframite even at 0℃. [ABSTRACT FROM AUTHOR]

Droplets are found to exhibit a finite residence time over the volatile liquid pool due to the confined evaporation mediated sustained thin film draining. The levitated drops are quite critical in biomedical applications such as for the biophysical micro reactors. It is hypothesized that the presence of surfactants can induce solutal Marangoni and can further enhance the levitation time. Moreover, the surfactant drops can closely mimic the bio drop assay. Droplets of surfactant solutions are allowed to impact over a series of volatile hydrocarbon oils to understand the effect of surfactant concentration, impact height and the properties of the oil pool using high speed imaging technique. Flow visualization is employed in the pendant droplet mode to understand the Marangoni induced internal circulation. The droplets of surfactant solutions are found to exhibit enhanced residence time compared to the case of non-surfactant drops. The levitation time is a function of the surfactant concentration and the volatility of the oil pool. A mathematical model is developed incorporating the effect of solutal Marangoni to test the hypothesis and is found to predict the levitation time with reasonable accuracy. A universal floating–sinking regime map was developed incorporating the influence of governing parameters. [Display omitted] • Solutal Marangoni aided passive levitation mechanism of droplets. • Critical criteria for the levitation is established. • Surfactant concentration is found to have a significant role in controlling thelevitation time. • Tunable levitation time may be achieved for biomedical applications. • Volatility of the pool is necessary to initiate the Marangoni effect. [ABSTRACT FROM AUTHOR]

Fluorescent ensemble based on PBI/SDS assemblies exhibiting cross-reactive responses and discriminative behaviors to multiple aminoglycoside antibiotics in both aqueous solution and serum samples. [Display omitted] • Three PBI-based fluorescent probes with different side chains were synthesized. • The structure and polarity of side chains influence aggregation behaviors of PBI derivatives in water. • SDS assemblies effectively modulate fluorescence emission of PBI with polar side chains. • Binary sensor system shows turn-on fluorescence responses to aminoglycoside antibiotics. • Ternary sensor system can discriminate multiple aminoglycoside antibiotics. Fluorescent aggregates and ensembles have been widely applied in fabrication of fluorescent sensors due to their capacity of encapsulating fluorophores and modulating their photophysical properties. In the present work, fluorescent ensembles based on anionic surfactant SDS assemblies and perylene derivatives (PBIs) were particularly constructed. Three newly synthesized neutral PBI derivatives with different structures, PO, PC1 and PC2, were used for the purpose to evaluate probe structure influence on constructing fluorescent ensembles. The one with hydrophilic side chains, PO, experienced distinct photophysical modulation effect by SDS assemblies. The ensemble based on PO@SDS assemblies displayed effective fluorescence variation to antibiotic aminoglycosides (AGs). To improve cross-reactivity and discrimination capability of ensembles, a second probe, coumarin, was introduced into PO@SDS assemblies. The resultant ternary sensor, CM-PO@SDS, exhibited good qualitative and quantitative detection capabilities, and achieved differentiation of eight AGs and mixed AG samples both in aqueous solution and actual biological fluid, like human serum. Sensing mechanism studies revealed that hydrogen bonding, electrostatic and hydrophobic interactions are involved in the sensing process. This surfactant-based fluorescent ensemble provides a simple and feasible method for assessing AGs levels. Meanwhile, this work may provide some insights to design reasonable probes for constructing effective single-system based discriminative fluorescent amphiphilic sensors. [ABSTRACT FROM AUTHOR]

Boiling is a prevalent phase-change process that plays a vital role in facilitating efficient heat transfer from a heating surface. While this heat transfer mechanism is generally effective, a rapid increase in surface temperature can lead to hydrodynamic instabilities, resulting in a boiling crisis. Previous studies have shown that surfactants often improve boiling performance and change the boiling crisis behavior. Conventional wisdom in this field attributes that these changes in boiling behavior are tied to the critical micelle concentration (CMC) of the particular surfactant. However, our work reveals that these changes in boiling behavior are independent of the CMC for three nonionic surfactants across a wide range of molar concentrations. In addition, visual snapshots of the bubbling behavior indicate changes in bubble formation, such as bubble size and nucleation site density, influenced by the molar concentration-dependent diffusion timescale of surfactants. Hence, these findings offer compelling evidence that boiling behavior, encompassing both boiling performance and boiling crisis, is governed by the dynamic adsorption of surfactants rather than dictated by the CMC. This becomes evident when quantifying the heat transfer coefficient (HTC) and critical heat flux (CHF) using the logarithm of molar concentration, as predicted by theory. Building upon these findings, we propose insights for controlling when CHF modification occurs in specific scenarios involving any surfactants. These insights hold significant potential for optimizing heat transfer processes and leveraging surfactants in energy-related applications to maximize boiling efficiency. • Boiling is influenced by surfactant adsorption dynamics. • Similar bubbling observed for different surfactants at the same molar concentrations. • Molar concentration-dependent diffusion governs boiling behavior. • Boiling trends validated with different boiler and surface type. [Display omitted] [ABSTRACT FROM AUTHOR]

Achieving circularity in the plastic economy predominantly depends on sourcing higher quality recyclates. Packaging plastic poses a significant challenge as it is often not prioritised for collection or recycling initiatives. The presence of additives, such as printing ink, impedes the quality of recyclates. Considering the volume of packaging plastics and the importance of branding (aesthetics and consumer information), ink removal is a critical pre-treatment step. However, the literature is limited, with only 14 studies exploring de-inking processes. Drawing parallels with the detergent laundering process, surfactants have been widely investigated in plastic de-inking, with cationic surfactants proving the most effective with a de-inking efficiency of up to 100%. However, concerns exist regarding the toxic and hazardous nature of the surfactants and chemicals. The average hazard quotient (AHQ) was developed, which compares de-inking chemicals as one of the key findings. AHQ provides a quantitative proxy for the hazards and toxicities, which are qualitatively presented as part of the globally harmonised system (GHS) classification of chemicals. To drive emerging packaging plastic de-inking, including the development of green surfactants (e.g. gamma-valerolactone), this work enables an informed chemical selection minimising potential hazards (rather than creating more adverse effects in plastic recycling processes) and toxicities from plastic waste, fulfilling the objectives of cleaner plastic waste recycling. [Display omitted] • De-inking is an undermined pre-treatment step in packaging plastic recycling. • There are concerns over the toxicity and hazards of surfactants used in de-inking. • This study critically analyses the state of the art of packaging plastic de-inking. • Developed a chemical selection tool that minimises hazards in three categories. • Bio-based and green chemicals should be explored for packaging plastic de-inking. [ABSTRACT FROM AUTHOR]

[Display omitted] • The synergistic of SDBS and PEI improves the dewatering performance of kaolin. • Analyze the action of the reagent, divide the pressure deformation into four parts. • Evaluate the dewatering effect of kaolin using a homemade dewatering device. • A small amount of PEI acts as flocculant also increasing the adsorption of SDBS. The objective of this study was to elucidate the synergistic dewatering mechanism of mixed sodium dodecylbenzene sulfonate (SDBS) and polyethyleneimine (PEI) on kaolinite filter cakes and to test the dewatering effectiveness of a custom-built pressure dewatering device. The dewatering experiments showed that while the reagent dose was reduced by 50%, the dewatering rate decreased to 19.78%, surpassing the optimal dose of a single reagent. During the natural compression stage of the filter cake, the deformation reached its maximum under the same pressure difference. During the transitional period, the closure of the filter cake pores occurred at a slower rate, facilitating better moisture drainage. Under strong compression, the ultimate deformation reached its maximum. PEI acted as a bridging agent for kaolin flocculation and served as a medium for SDBS on the kaolin surface. A small amount of PEI reduced the electrostatic repulsion of SDBS, increasing its adsorption capacity. PEI adsorbed on the kaolin surface through electrostatic and hydrogen bonding, while SDBS could adsorb onto the PEI reagent layer through electrostatic and polar interactions, exposing its alkyl chains on the surface and thereby facilitating flocculation and generating a hydrophobic reagent layer. This study could provide a new method and insights for the efficient pressurized dewatering of kaolin. [ABSTRACT FROM AUTHOR]