Cold-pressed oils are oils prepared from pressing plant materials with a screw or hydraulic press, yielding oils with little contamination of harmful chemicals and high content of nutrients and functional constituents. Cold-pressed oils have gained increasing recognition as food supplements for preventing and ameliorating body deterioration due to ageing and the progression of lifestyle diseases or non-communicable diseases. This article aimed to review their structure, bioactivity, and chromatographic analysis of the mostly found functional compounds in cold-pressed oils, including phytosterols, carotenoids, tocols (tocopherols and tocotrienols), phenolic compounds (flavonoids, phenolic acids, tannins, stilbenes, and lignans), and squalene.

In 2021, we published three papers related to the anti-inflammatory effects of food ingredients. The present paper reports the effects of vitamin E homologs and sweet basil powder. In these papers, we investigated whether inflammation occurs in the adipose tissue of mice fed a high-fat and high-sucrose diet for 16 weeks. Inflammatory cytokine gene expression was significantly higher in the epididymal fat of the high-fat and high-sucrose diet group than in that of the control diet group. However, the addition of α-tocopherol or δ-tocopherol to the diet could not restrain the inflammation of mice epididymal fats. Thereafter, we investigated the anti-inflammatory effects of α- and δ-tocopherols using the co-cultured cells. Consequently, we clarified that δ-tocopherol inhibited the increase in the gene expressions of inflammatory cytokines. We also examined the effect of sweet basil powder on a similar obese mice model. The final body weight in the high-fat and high-sucrose group that received sweet basil powder was significantly lower than that in the high-fat and high-sucrose diet group. Liver weights were also significantly lower in the high-fat and high-sucrose diet group that received sweet basil powder than in the high-fat and high-sucrose diet group, although adipose tissue weights were unchanged in both groups. Furthermore, sweet basil powder tended to inhibit in lipid synthesis in the mice livers. Therefore, we suggested that sweet basil powder inhibited fatty acid synthesis in mice livers, thereby suppressing liver enlargement, and resulting in body weight loss. Moreover, the gene expression of MCP-1 in the adipose tissue of mice fed a high-fat and high-sucrose diet added with sweet basil powder was significantly lower than that of mice fed a high-fat and high-sucrose diet for 12 weeks. Therefore, sweet basil powder inhibited inflammation onset in the adipose tissue of mice. Taken together, the results suggested that food ingredients, especially vitamin E homologs and sweet basil powder, have anti-inflammatory effects on mice adipose tissue and mice adipocyte-induced inflammation.

Phospholipids and surfactants form membranes and other self-assembled structures in water. However, it is not fully understood how the surrounding water (hydration water) is involved in their structure formation. In this paper, I summarize the results of our investigation of the long-range hydration state of phospholipids and surfactants at their surfaces by means of terahertz spectroscopy. By observing the collective rotational dynamics of water in the picosecond time scale, this technique allows us to observe not only the water directly bound to the solute, but also the weakly affected water outside of it. For example, PC phospholipids inhibit water dynamics over long distances, whereas PE phospholipids make water more mobile than bulk water. The causes of this difference in hydration and how it is involved in the structural formation of the membrane are reviewed.

Sacha inchi (Plukenetia volubilis) oil is constituted with macronutrients and the health benefit fatty acids. In this context, the efficient of Sacha inchi oil for anti-aging product is presented. The light-clear yellowish seed oil of Sacha inchi was revealed on its physicochemical properties that are in the same range of the commercializing plant-oil supplied for topical products. The oil was GC/MS exhibited to be constituted with α-linolenic (51.72%) and linoleic (24.3%) acids, with unsaturated/saturated fatty acids ratio of 21.26. The oil was noted onto its potent in vitro antioxidant activity assessed by ABTS, DPPH and FRAP assays. In addition, the oil (1-3%) was proved to be safe in normal human fibroblast cells. Furthermore, the oil exhibited cellular antioxidant with inhibitory effect against MMP-2. Sacha inchi oil is therefore highlighted as a potential source of nutraceutical especially for anti-aging product. The oil is specified for the product development in terms of physicochemical, chemical and biological profiles. Innovative processing of Sacha inchi is therefore encouraged as the promising plant for anti-aging product.

Polyhexamethylene guanidine (PHMG) is a guanidine-based chemical that has long been used as an antimicrobial agent. However, recently raised concerns regarding the pulmonary toxicity of PHMG in humans and aquatic organisms have led to research in this area. Along with PHMG, there are concerns about the safety of non-guanidine 5-chloro-2-methylisothiazol-3(2H)-one/2-methylisothiazol-3(2H)-one (CMIT/MIT) in human lungs; however, the safety of such chemicals can be affected by many factors, and it is difficult to rationalize their toxicity. In this study, we investigated the adsorption characteristics of CMIT/ MIT on a model pulmonary surfactant (lung surfactant, LS) using a Langmuir trough attached to a fluorescence microscope. Analysis of the π-A isotherms and lipid raft morphology revealed that CMIT/MIT exhibited minimal adsorption onto the LS monolayer deposited at the air/water interface. Meanwhile, PHMG showed clear signs of adsorption to LS, as manifested by the acceleration of the L _o phase growth with increasing surface pressure. Consequently, in the presence of CMIT/MIT, the interfacial properties of the model LS monolayer exhibited significantly fewer changes than PHMG.

High-performance size exclusion chromatography (HPSEC) equipped with an evaporative light scattering detector (ELSD) was utilized for characterization of palm fatty acid distillate (PFAD) and its esterified products, with a particular focus on lipid profiles and diacylglycerol (DAG) regioisomers. The separation of triacylglycerol (TAG), DAG, monoacylglycerol (MAG), and free fatty acid (FFA) was achieved through a single 100-Å Phenogel column, coupled with a 2-cm C18 guard, utilizing toluene/acetic acid (100:0.25, v/v) as the mobile phase. This separation was based on size sieving principles and the interactions between the hydroxyl group(s) and the Phenogel matrix. The limit of detection (LOD) and limit of quantification (LOQ) for the esterified PFAD products analyzed by this method fell within the range of 4.8-5.5 μg/mL and 14.7-16.7 μg/mL, respectively. Additionally, the same column, paired with a 2-cm silica guard and a mobile phase comprised of toluene/isooctane/acetic acid (35:65:0.15, v/v/v), was used for the characterization of DAG regioisomers within the esterified PFAD. LODs and LOQs for sn-1,3-DAG and sn- 1,2-DAG were determined to be 39.2 and 118.7 μg/mL, and 32.8 and 99.5 μg/mL, respectively. Investigation of esterified PFAD products prepared using 4% H₂SO₄ at 120°C. After 2 h, the analysis revealed the highest MAG content at 31.85%, accompanied by 51.54% DAG, 2.35% TAG, and a residual 14.27% FFA. Notably, as the reaction time extended, the MAG content decreased, while both DAG and TAG levels exhibited an increasing trend. Further examination of DAG regioisomers during PFAD esterification, under varying catalyst concentrations (2-10%) and reaction temperatures (80-140°C), demonstrated a significant increase in the percentage of sn-1,3-DAG, inversely correlated with the reduction in FFA from 2% H ₂ SO ₄ and 80°C onwards. Remarkably, the percentage of sn-1,2-DAG remained relatively stable regardless of changes in catalyst concentrations or temperatures, confirming its susceptibility to isomerization into the thermodynamically more stable sn-1,3-DAG form. This study provides valuable insights into the composition and behavior of esterified PFAD products.

In this study, the phospholipid species [i.e., phosphatidylethanolamine (PE), phosphatidylcholine (PC), and sphingomyelin (SM)] in human milk (HM) were compared according to their fatty acid (FA) composition. 34 HM samples were collected and classified into three groups (A < B < C) according to their fat content. Stearic acid (C18:0) was the main FA in PE, PC, and SM. The highest concentrations of arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosapentaenoic acid (DPA) were observed in PE, whereas docosahexaenoic acid (DHA) was predominant in SM. Although PC exhibited the highest total saturated FAs (SFAs) and PE contained the highest unsaturated FAs (UFAs), very long-chain SFAs and monounsaturated FAs (MUFAs) were preferentially distributed in SM. PC and SM had higher saturation compared to PE. Regarding the effect of the fat content of HM on the FA composition of the phospholipid species, a limited influence was observed on the composition of SFAs and MUFAs of PE, SM, and particularly PC. However, a more pronounced effect on the composition of polyunsaturated FAs (PUFAs) in phospholipids was observed, especially for linoleic acid (LA), α-linolenic acid (ALA), EPA, and DHA, indicating that the composition of FAs in the phospholipid species was probably affected by the maternal diet.

Rice bran (RB) and rice bran oil (RBO) are exploring as prominent food component worldwide and their compositional variation is being varied among the world due to regional and production process. In this study, Fermented Rice Bran (FRB) was produced by employing edible gram-positive bacteria (Lactobacillus acidophilus, Lactobacillus bulgaricus and Bifidobacterium bifidum) at 125×10 ⁵ spore g ^–1 of rice bran, and investigated to evaluate nutritional quality. The Crude Rice Bran Oil (CRBO) was extracted from RB and its quality was also investigated compared to market available rice bran oil (MRBO) in Bangladesh. We found that fermentation of rice bran with lactic acid bacteria increased total proteins (29.52%), fat (5.38%), ash (48.47%), crude fiber (38.96%), and moisture (61.04%) and reduced the carbohydrate content (36.61%). We also found that essential amino acids (Threonine, valine, leucine, lysine, histidine and phenylalanine) and non-essential amino acids (alanine, aspartate, glycine, glutamine, serine and tyrosine) were increased in FRB except methionine and proline. Moreover, total phenolic content, tannin content, flavonoid content and antioxidant activity were increased in FRB. The RBO analysis showed that γ-oryzanol content (10.00 mg/g) were found in CRBO compared to MRBO (ranging 7.40 to 12.70 mg/g) and Vitamin-E content 0.20% were found higher in CRBO compared to MRBO (ranging 0.097 to 0.12%). The total saturated (25.16%) and total unsaturated fatty acids (74.44%) were found in CRBO whereas MRBO contained total saturated (22.08 to 24.13%) and total unsaturated fatty acids (71.91 to 83.29%) respectively. The physiochemical parameters (density, refractive index, iodine value) were found satisfactory in all sample except acid value and peroxide value higher in CRBO. Heavy metal concentration was found within an acceptable range in both CRBO and MRBO. Thus FRB and RBO could be value added food supplement for human health.

Global demand for epoxidized vegetable oil has been steadily growing. Epoxidized vegetable oils are typically produced using a two-pot synthesis process in which the oxidation and epoxidation reactions are carried out sequentially. This two-pot synthesis method, however, has a major drawback in industrialscale production, particularly when it comes to operational and process safety issues. A laboratory-scale one-pot synthesis method was attempted in this study with the aim to safely synthesize epoxidized Moringa Oleifera oil (eMOo) by avoiding the occurrence of undesired exothermic runaway reaction. The oil extracted from Moringa Oleifera oil seed kernel (MOo) was used as a starting component due to its high degree of unsaturation and also because the Moringa Oleifera plant can be freely grown in any soil conditions. Two parallel oxidation and epoxidation reactions were carried out simultaneously in this one-pot synthesis method to produce eMOo. The effect of five different mole ratios of MOo, acetic acid and hydrogen peroxide (1:1:1, 1:1:2, 1:1.5:2, 1:1.75:2 and 1:2:2, respectively) on reaction mechanism was investigated at the controlled temperature range of 43 – 55°C and reaction time of 0 - 120 min. The physicochemical properties of MOo as well as the oxirane oxygen content (OOC) of the resulting eMOo were characterized. In addition, GC-MS and FTIR analysis were performed to verify the molecular composition of MOo and also to identify the epoxy group of the resulting eMOo respectively. Among the five different mole ratios studied, the 1:1.5:2 mole ratio has the highest unsaturation conversion of 79.57% and OOC of 4.12%.

Skincare industries are growing rapidly around the globe but most products are formulated using synthetic chemicals and organic solvent extracted plant extracts, thus may be hazardous to the users and incur higher cost for purification that eventually leads to phytonutrient degradation. Therefore, this study aimed to formulate a stable natural formulation with antioxidant and antimicrobial activities by using supercritical carbon dioxide (SC-CO ₂ ) extracted palm-pressed fiber oil (PPFO) as an active ingredient with virgin coconut oil (VCO) as a formulation base. PPFO was extracted from fresh palm-pressed fiber (PPF) while VCO was from dried grated coconut copra using SC-CO ₂ before being subjected to the analyses of physicochemical properties, phytonutrient content and biological activities including antioxidant and antimicrobial. The nanoemulgel formulations were then developed and examined for their stability through accelerated stability study for 3 months by measuring their pH, particle size, polydispersity index and zeta potential. The results showed that PPFO contained a high amount of phytonutrients, especially total carotenoid (1497 ppm) and total tocopherol and tocotrienol (2269 ppm) contents. The newly developed nanoemulgels maintained their particles in nano size and showed good stability with high negative zeta potentials. Sample nanoemulgel formulated with 3% PPFO diluted in VCO as effective concentration showed significantly stronger antioxidant activity than the control which was formulated from 3% tocopheryl acetate diluted in mineral oil, towards DPPH and ABTS radicals, with IC ₅₀ values of 67.41 and 44.28 µL/mL, respectively. For the antibacterial activities, the sample nanoemulgel was found to inhibit Gram positive bacteria S. aureus and S. epidermidis growth but not the Gram negative strain E. coli. Overall, this study revealed the potential of SF-extracted PPFO as an active ingredient in the antioxidant topical formulations thus future study on in vitro skin cell models is highly recommended for validation.

This study was investigated the effect of adding fat to pork sausage on taste and aroma persistence. Sensory evaluation indicated that increasing fat content intensified umami and saltiness perception, enhancing the mouthfulness and flavor persistence, leading to Koku enhancing effect. Gas chromatography/mass spectrometry (GC/MS) analysis identified aroma compounds such as β-pinene, 3-carene, D-limonene, octanal, nonanal, caryophyllene, and methyl eugenol, which were consistently present regardless of fat content. These aroma compounds were less likely to be released as the fat content increased. Furthermore, the release of these aroma compounds from the sausage with addition of fat was larger than that without addition of fat in the presence of saline, indicating that the added fat retained these aroma compounds and released them in the presence of saline. This suggests that sausages with added fat release more aroma compounds during consumption, resulting in a more intense flavor and flavor persistence of Koku perception. These seven compounds detected in pork sausage were found to be easily retained by cholesterol and lecithin, likely due to differences in their log P values (octanol/water partition coefficients), which were greater than 3.

Motion is an essential feature of living systems. Microorganisms autonomously change their nature in response to slight changes in the surrounding environment induced by external stimuli and exhibit unique motion modes. Various self-propelled objects have been constructed to understand these behaviors. Towards achievement of such purpose, the precise settings of experimental conditions including fabrication of objects with a shape anisotropy have been made attempts in the field of active matter and supramolecular chemistry. This review describes the recent progress in inducing the self-propelled motion of artificial objects. If life-like dynamic behavior such as self-propelled motion can be designed and experimentally induced from molecular properties, it will be easier to control functions expressed as outputs. This will lead to not only a better understanding of the complex functions in living systems, but also the fabrication of exotic materials with life-like properties.

Vitamin E (VE) is a lipophilic vitamin, and Evans and Bishop demonstrated the existence of a hitherto unrecognized dietary factor essential for normal reproduction in rat. During 100 years after the discovery, α-tocopherol (α-Toc) has been the representative species in VE homologues, and both naturally occurring and synthetically prepared α-Toc have been widely used and studied. Although it is indicated by a single-word VE, research on VE involves various chemical species. It is important to understand the fine structure and accurate characteristics of individual VE species when using VE. Each VE sample has compositional and/or isomer issues, and furthermore, the usability greatly varies depending on the modified species of esterification. The VE industry involves many interdisciplinary fields. Improvements in formulation technology and confirmation of the novel biological activity of VE greatly owns its utility and opens up new applications. As the interim period between the start and end of the agenda for Sustainable Development Goals (SDGs), in this minireview, the recent trends and future guidelines of VE, especially α- Toc, in relation to the SDGs have been demonstrated.

Mannosylerythritol lipid (MEL) has attracted much attention as an environmentally benign and biocompatible material in many research fields due to its significant biochemical and physiological properties. However, heterogeneity always exists in MEL obtained from microbial products with respect to the chain length of the fatty acids. In this context, the total synthesis of the 20 members of MEL was effectively and stereoselectively achieved using our boron-mediated aglycon delivery (BMAD) method. In addition, structure-function relationship (SFR) studies of antibacterial activity, self-assembling properties, and recovery effects on damaged skin cells have been conducted, and these results are introduced in this mini-review article.

Physicochemical investigations on the inclusion of anionic polyamidoaminesuccinamic acid dendrimer, generation 5 (PAMAM-SA, G5) with positively charged hybrid vesicles (HCV), prepared using soylecithin, ion pair amphiphile (IPA), cholesterol and dihexadecyldimethylammonium bromide, were investigated by dynamic light scattering, transmission electron/atomic force microscopy (TEM/AFM), differential scanning calorimetry, fluorescence spectroscopy and surface pressure-time isotherm studies. Adsorption of dendrimer onto vesicle surface and subsequent bilayer disruption strongly depends on the bilayer composition and dendrimer concentration. Change in the zeta potential value with increasing dendrimer concentration suggests the dendrimer-vesicle interaction to be electrostatic in nature. AFM studies also confirm the adsorption of dendrimer as well as hole formation in the bilayer. Impact of the inclusion of dendrimer into the bilayer were further investigated through differential scanning calorimetry by monitoring the chain melting temperature and enthalpy of the chain melting processes. Dendrimer at low concentration does not alter bilayer integrity, while hole formations are noted at higher dendrimer concentration. Fluorescence anisotropy studies confirm the adsorption and subsequent bilayer disruption due to dendrimer inclusion. Dendrimer induced vesicle disintegration kinetics conclusively illustrate the transformation of cationic bilayer to monolayer and thereby exposing the role of IPA. In vitro cytotoxicity studies on PAMAM-SA, G5 and HCVs mixtures against human breast cancer cell line suggest that dendrimer-liposome aggregates (dendriosomes) exhibit substantial anticancer activities with insignificant side effects. It is expected that the dendriosomes may have application to host and deliver anticancer drug in the field of targeted drug delivery.

The solubility and permeability of the Biopharmaceutics Classification System (BCS) class IV drugs, such as furosemide (FUR), are low. Thus, the oral bioavailability of these drugs needs to be augmented. Here, we aimed to design orally disintegrating tablets containing FUR nanoparticles to improve bioavailability after oral administration. The FUR nanoparticles were generated by bead-milling in water containing 0.5% methylcellulose and 0.5% 2-hydroxypropyl-β-cyclodextrin (w/w%). Particle size was approximately 47–350 nm (mean particle size, 188 nm). An orally disintegrating tablet (FUR-NP tablet) comprising FUR nanoparticles (1%) was successfully produced by employing suspensions outlined above that incorporated additives (4% D-mannitol, 0.4% polyvinylpyrrolidone, and 16% gum Arabic, w/w%), followed by freeze-drying. The FUR-NP tablet disaggregated after only 5 s in water, liberating nano-sized FUR particles (172 nm). Experiments using rats showed the absorption of the FUR-NP tablet was significantly improved by comparison with a FUR tablet containing microparticles. In summary, the orally disintegrating tablet containing FUR nanoparticles markedly enhanced the bioavailability of FUR. We anticipate this formulation will also improve the bioavailability of other BCS class IV drugs.

We present a CuAAC (Copper-Catalyzed Azide-Alkyne Cycloaddition) reaction protocol designed for the visualization of mRNA. To achieve this, we synthesized stable mRNA molecules incorporating the modified nucleoside analog, EU, a crucial element for fluorophore attachment. Leveraging this modified mRNA, we successfully executed the CuAAC reaction, wherein the pro-fluorophore, coumarin, was conjugated to EU on the mRNA through our meticulously designed CuAAC process. This innovative approach resulted in the emission of fluorescence, enabling both precise quantification and visual observation of mRNA. Furthermore, we demonstrated the feasibility of concurrent mRNA synthesis and visualization by seamlessly integrating the CuAAC reaction mix into the mRNA transcription process. Additionally, our novel methodology opens avenues for prospective real-time monitoring of mRNA transcription within artificial cells. These advancements hold significant promise for expanding our comprehension of fundamental cellular processes and finding applications across diverse biological contexts in the future.

In this study, it is demonstrated that natural microalgae oils, which contain fatty acid components including docosahexaenoic acid (DHA), could be directly applied to fabricate vesicular structures in aqueous phase through a forced formation process. The microalgae oil vesicles had initial average diameters of 170- 230 nm with negative charges apparently caused by dissociation of the fatty acid components. The vesicles possessed excellent stability with lifetimes for at least 450 days. The formation of the vesicular structures with hydrophilic cores/regions was confirmed by the transmission electron microscopy (TEM) image and successful encapsulation of a hydrophilic material. For encapsulation of a hydrophobic material, lutein, the vesicle size was increased probably due to the insertion of lutein into the hydrophobic vesicular bilayer structures. The analysis of Fourier transform infrared (FTIR) spectroscopy suggested that the vesicular bilayer fluidity was decreased by encapsulating lutein. However, the lutein-encapsulating microalgae oil vesicles still possessed high stability and the vesicular structures could maintain intact even at an environmental temperature up to 60℃. Applicability of the microalgae oil vesicles as drug delivery carriers was also demonstrated by successful encapsulation of curcumin. However, when the loaded curcumin was increased to a certain amount, physical stability of the microalgae oil vesicles was significantly reduced. This is probably because the vesicular structures with only limited spaces for accommodating hydrophobic materials were strongly affected by encapsulating a large amount of curcumin. It is interesting to note that by adding egg L-α-phosphatidylcholine, the curcumin encapsulation-induced instability of the microalgae oil vesicles could be alleviated. The results indicated that vesicular structures could be fabricated from microalgae oils and the microalgae oil vesicles were capable of encapsulating hydrophilic or hydrophobic materials for drug delivery applications. The findings lay a background for further dosage form development of nutritional supplements encapsulated by natural microalgae oils.

Infiltration of binary solution of hexane and ethanol into chromatography paper associated with their evaporation was found to generate unexpected initial rapid advancement of wicking front followed by its receding and readvancing in our previous research. In the present study, paper chromatography development of hydrophobic dye, Sudan III, and hydrophilic dye, Acid Blue 9, was carried out using binary solutions of hexane and ethanol in open environment, allowing the developing solvent been evaporated. Sudan III was developed with initial rapid advancing wicking front, while Acid Blue 9 was scarcely developed. On the other hand, Acid Blue 9 was developed with the readvancing second wicking front, while the spot of Sudan III scarcely migrated. Thus, the unexpected illusional phenomenon, overtaking the spot of Sudan III by the spot of Acid Blue 9, was observed. The readvancement of the second wicking front was found to be enhanced as increasing the relative humidity in the environment. Surface temperature of the chromatography paper was measured during the chromatographic development in open environment to show that it became lower than the dew point when the experiments were carried out in relatively high humidity. Solubility of Sudan III in a binary solution of ethanol and water remarkably decreased as increasing the content of water. It was thus suggested that the water vapor condensation to induce water mixing into the mobile phase to decrease the solubility of Sudan III to inhibit its chromatographic development to realize the illusional spot overtaking of dyes of their chromatographic development associated with solvent evaporation.

Factors affecting the in vitro Sun Protection Factor (SPF) and Ultraviolet-A Protection Factor (UVA-PF) of sunscreens were analyzed for verifying the validity and reliability of the ISO24443 evaluation method. UV absorbance measurements by different spectrophotometers did not lead to the large difference in in vitro SPF/UVA-PF, although the UV absorbance determined by each spectrophotometer exhibited relatively large difference when it was larger than 2. On the other hand, relatively large difference was found in in vitro SPF/UVA-PF by utilizing European Cosmetic and Perfumery Association (Colipa) 1994 or UV-solar simulated radiation (UV-SSR) for the spectral irradiance. Appropriateness of employing the coefficient of adjustment for the determination of in vitro UVA-PF was also found to be reexamined.

External stimuli-responsive worm-like micelles (WLMs) have the potential for a wide range of applications. In particular, sugar (a polyol compound)-responsive WLMs have the potential for use in smartdrug release systems. Phenylboronic acid (PBA) functions as a cis-diol sensor in a similar manner it does as a glucose sensor. Thus, WLMs, primarily composed of surfactants and PBA, are expected to function as cis-diol-responsive viscoelastic systems. PBA also reacts irreversibly with hydrogen peroxide (H₂O₂ ) and is converted into phenol and boric acid. H₂O₂ is one of reactive oxygen species crucial for several physiological processes. Therefore, H₂O₂ -responsive WLMs have the potential for various applications. In this review, we describe cis-diol- and H₂O₂ -responsive micellar systems composed of cetyltrimethylammonium bromide and PBA moieties that shift their viscosities in response to stimuli.

The distribution of electrolytes near the air/water surface plays an essential role in many processes. While the general distribution is governed by classic Poisson-Boltzmann statistics, the analytical solution is only available for symmetric electrolytes. From the recent studies in the literature, it is evident that surface adsorption is dependent on specific ions as well as the H-bond structure at the surface. Experimental data can capture the macro properties of the surface, such as surface tension and surface potential. Yet, the underpinning mechanisms behind this experimental macro-observation remain unclear. To address the challenge, we developed a framework combining experimental studies and numerical calculations. The model was developed for electrolytes with unequal cationic and anionic charges. The asymmetric model was successfully applied to describe the surface charge of MgCl ₂ aqueous solution. The results can be explained by the role of cationic size and charge on the surface layer.

The direct incorporation of low viscosity organic liquids (OL) such as dodecane and tributylphosphate (TBP) into fresh geopolymers (GP) is difficult and generally leads to variable amounts of un-incorporated OL remaining outside the hardened geopolymer. Experimentally, it is observed that a regular torque increase during OL incorporation corresponds to a suitable dispersion of the OL in the form of fine micrometric droplets. This can be obtained for TBP and dodecane by adding a small quantity of quaternary ammoniums salts (QAs) such as cetyltrimethylammonium bromide (CTAB). Shorter alkyl chains QAs, such as hexamethyltrimethylammonium (HMTA) can also be used but with a reduced efficiency. The positive impact of CTAB is then confirmed by the Washburn capillary rise method, showing that the interactions between TBP and CTAB-modified metakaolin are weaker compared to untreated powder. Finally, it is observed that the incorporation of TBP into geopolymer slurries is much easier than the incorporation of dodecane. The low interfacial tension measured between TBP and the activating solution (around 8 mN·m ^–1 ), contrasting with dodecane (29 mN·m ^–1 ), explains that the dispersion of TBP droplets in fresh metakaolin suspensions is more efficient.