Emulsion Research Articles

Simultaneous use of disulphide oil for chemical‐enhanced oil recovery by emulsion formation and stability with asphaltene deposition control

AbstractDisulphide oil (DSO) is a by‐product of oil and gas refining processes that is generated during the removal of mercaptans and the sweetening of light hydrocarbons. Asphalt deposition, especially asphaltene deposition during enhanced oil recovery methods, reduces oil recovery from the reservoir, so the use of a substance such as DSO, which has the ability to control and reduce asphaltene deposition, can be effective in increasing oil recovery from the reservoir. In this research, a micromodel with a fracture design and a matrix that represents fracture reservoirs was utilized. These tests were conducted in two groups. The first group of tests is related to adding DSO to crude oil and using 70 to 30 vol.% oil–water emulsion containing salt, surfactant, and nanoparticles. The second group involved adding DSO to both crude oil and emulsion. The first group aimed at stimulation and the second group aimed at chemical enhanced oil recovery (C‐EOR). The formation and stability of water‐in‐oil emulsion was done by analyzing the average droplet size. As a result, in the first group of tests with the presence of DSO in the oil, by measuring the average diameter before and after injection of AOS surfactant, it was observed that the average droplet size decreased from 6.89 to 4.01 μm, which indicates an increase in the emulsion stability. In the second group, where DSO was present in both oil and water emulsion in injected oil, it can be seen that the average diameter of the droplets in the surfactant decreased from 5.12 to 3.21 μm.

Nanoemulsion and nanoemulgel-based carriers as advanced delivery tools for the treatment of oral diseases.

Oral diseases rank among the most widespread ailments worldwide posing significant global health and economic challenges affecting around 3.5billion people, impacting the quality of life for affected individuals. Dental caries, periodontal disease, bacterial and fungal infections, tooth loss and oral malignancies are among the most prevalent global clinical disorders contributing to oral health burden. Traditional treatments for oral diseases often face challenges such as poor drug bioavailability, breakdown of medication in saliva, inconsistent antibiotic levels at the site of periodontal infection as well as higher side effects. However, the emergence of nanoemulgel (NEG) as an innovative drug delivery system offers promising solutions where NEG combines the advantages of both nanoemulsions (NEs) and hydrogels providing improved drug solubility, stability, and targeted delivery. Due to their minuscule size and ability to control drug release, NEGs hold promise for improving treatment of oral diseases, where versatility of these delivery systems makes them suitable for various applications, including topical delivery in dentistry. This review concisely outlines the anatomy of the oral environment and investigates the therapeutic potential of NE-based gels in oral disorder treatment. It thoroughly examines the challenges of drug delivery in the oral cavity and proposes strategies to improve therapeutic efficacy, drawing attention to previous research reports for comparison. Through comprehensive analysis, the review highlights the promising role of NEGs as a novel therapeutic approach for oral health management via research advancements and their clinical translation. Additionally, it provides valuable insights into future research directions and development opportunities in this area.

Optimisation and Composition of the Recycled Cold Mix with a High Content of Waste Materials

This research focuses on a mineral–cement mixture containing bitumen emulsion, designed for cold recycling procedures, the formulation of which includes 80% (m/m) of waste material. Deep cold recycling technology from the MCE mixture guarantees the implementation of a sustainable development policy in the field of road construction. The utilised waste materials include 50% (m/m) reclaimed asphalt pavement (RAP) from damaged asphalt layers and 30% (m/m) recycled aggregate (RA) sourced from the substructure. In order to assess the possibility of using a significant amount of waste materials in the composition of the mineral–cement–emulsion (MCE) mixture, it is necessary to optimise the MCE mix. Optimisation was carried out with respect to the quantity and type of binding agents, such as Portland cement (CEM), bitumen emulsion (EMU), and redispersible polymer powder (RPP). The examination of the impact of the binding agents on the physico-mechanical characteristics of the MCE blend was performed using a Box–Behnken trivalent fractional design. This method has not been used before to optimise MCE mixture composition. This is a novelty in predicting MCE mixture properties. Examinations of the physical properties, mechanical properties, resistance to the effects of climatic factors, and stiffness modulus were conducted on Marshall samples prepared in laboratory settings. Mathematical models determining the variability of the attributes under analysis in correlation with the quantity of the binding agents were determined for the properties under investigation. The MCE mixture composition was optimised through the acquired mathematical models describing the physico-mechanical characteristics, resistance to climatic factors, and rigidity modulus. The optimisation was carried out through the generalised utility function UIII. The optimisation resulted in indicating the proportional percentages of the binders, enabling the assurance of the required properties of the cold recycled mix while utilising the maximum quantity of waste materials.

Coalescence Frequency in O/W Emulsions: Comparisons of Experiments with Models.

We have studied the coalescence of oil in water emulsions under the influence of gravity. The emulsions were made with alkane oils and surfactants with varying physical chemistry. We chose cationic alkyl trimethylammonium bromides of different chain lengths and nonionic surfactants of ethylene oxide and sugar head groups, including polymeric surfactants. We observed phase separation in two steps. Creaming of the oil drops is followed by their rapid coalescence, increasing the average drop size and resulting in complete surfactant surface coverage of the interfaces. Full phase separation occurs after much longer times Tc when the emulsion drops coalesce dramatically. We have used a model by Dinh et al. to relate Tc to the coalescence frequency and hence to the activation energy for the rupture of the films between two neighboring drops. Our results support the view that the coalescence of stable emulsions (stable at least for a few hours) is a thermally activated process and is controlled by the surface compression elastic modulus. This modulus was determined using surface tension measurements and calculations using the Gibbs adsorption equation. The observed differences between ionic and nonionic systems are attributed to a two-step film rupture process in the case of ionic surfactants, which is not found in nonionic systems.

Fabrication of hierarchically porous trabecular bone replicas via 3D printing with high internal phase emulsions (HIPEs)

Combining emulsion templating with additive manufacturing enables the production of inherently porous scaffolds with multiscale porosity. This approach incorporates interconnected porous materials, providing a structure that supports cell ingrowth. However, 3D printing hierarchical porous structures that combine semi-micropores and micropores remains a challenging task. Previous studies have demonstrated that using a carefully adjusted combination of light absorbers and photoinitiators in the resin can produce open surface porosity, sponge-like internal structures, and a printing resolution of about 150µm. In this study, we explored how varying concentrations of tartrazine (0, 0.02, 0.04, and 0.08 wt%) as a light absorber affect the porous structure of acrylate-based polymerized medium internal phase emulsions fabricated via vat photopolymerization. Given the importance of a porous and interconnected structure for tissue engineering and regenerative medicine, we tested cell behavior on these 3D-printed disk samples using MG-63 cells, examining metabolic activity, adhesion, and morphology. The 0.08 wt% tartrazine-containing 3D-printed sample (008 T) demonstrated the best cell proliferation and adhesion. To show that this high internal phase emulsion (HIPE) resin can be used to create complex structures for biomedical applications, we 3D-printed trabecular bone structures based on microCT imaging. These structures were further evaluated for cell behavior and migration, followed by microCT analysis after 60 days of cell culture. This research demonstrates that HIPEs can be used as a resin to print trabecular bone mimics using additive manufacturing, which could be further developed for lab-on-a-chip models of healthy and diseased bone.

Fabrication of stable oleogel-in-water nanoemulsions with ethyl cellulose nanoparticles

Nanoemulsions (NEs) are liquid-based nanosized colloidal systems offering advantages (superior kinetic stability and rheology) compared to macro- and microemulsions. However, stabilization of these emulsions is difficult, since the small droplet sizes in NEs present large surface area-to-volume ratios. Thus, they need to be stabilized by superb emulsifiers to maintain stability. Herein, we report the construction of novel oleogel-in-water NEs with excellent stability against coalescence and phase separation. To do this, nanoparticles (NPs), based on ethylcellulose (EC), were first prepared, and then NEs were made using EC oleogel as the oil phase, ECNPs solution as the water phase, and tween-80 (TW80) as the surfactant. It was observed that NE stabilized by ECNPs, EC oleogel, and TW80 had a significantly lower particle size (201.86±1.57 nm), polydispersity index (0.13±0.06), with no phase separation over 30 days of storage as well as a higher zeta potential (-79.68±1.36 mV), and complex modulus (21441.80±418.21 kPa), as compared to the control NE (stabilized only by TW80). According to the findings, the developed NE has the potential for food and drug delivery applications.

Antimicrobial Effects of Eugenol-Based Micro- and Nano-Emulsions: Evaluation of Shelf-Life Enhancement in Sikhye

This study investigated the antibacterial properties of micro-emulsions (MEs) and nano-emulsions (NEs) containing eugenol and rice bran oil to enhance the shelf life of Sikhye, a traditional Korean rice beverage. The emulsions were evaluated using the agar disk diffusion method and minimum inhibitory concentration (MIC) tests against Escherichia coli, Bacillus cereus, and Staphylococcus aureus. The results demonstrated that MEs exhibited larger inhibition zones and lower MIC values than NEs, indicating superior antibacterial activity. The application of these emulsions in Sikhye revealed that a higher eugenol content and larger droplet size effectively inhibited bacterial growth. The study also found that, while rice bran oil contributed to physical stability, it did not enhance the antimicrobial effect and, in some cases, promoted bacterial growth. Overall, these findings suggest that eugenol-rich MEs could serve as effective natural preservatives, improving the safety and shelf life of Sikhye and potentially other food products.

Rubisco at interfaces II: structural reassembly enhances oil-water interface and emulsion stabilization

Rubisco at interfaces II: structural reassembly enhances oil-water interface and emulsion stabilization

Investigation of the synergistic effects of SiO2 and Al2O3 nanoparticles with SDS and CTAB surfactants on the stability and improving phase behavior of water-oil emulsions

Investigation of the synergistic effects of SiO2 and Al2O3 nanoparticles with SDS and CTAB surfactants on the stability and improving phase behavior of water-oil emulsions

Highly stable and flexible electronic separator prepared through photo-polymerizing fluorinated acrylate high internal phase emulsion

Highly stable and flexible electronic separator prepared through photo-polymerizing fluorinated acrylate high internal phase emulsion

UV-C-Activated Riboflavin Crosslinked Gelatin Film with Bioactive Nanoemulsion for Enhanced Preservation of Fresh Beef in Modified Atmosphere Packaging

This study explores a new eco-friendly approach for developing bioactive gelatin films using UV-C irradiation-induced photo-crosslinking. Riboflavin, a food-grade photoinitiator, was selected at an optimal concentration of 1.25% (w/w) for crosslinking gelatin under UV-C exposure for 4 to 22 min. Physicochemical analyses revealed enhanced tensile strength, reduced water vapor permeability, and lower water solubility in films crosslinked for up to 13 min. FTIR analysis demonstrated significant molecular changes, confirming the formation of crosslinking connections in gelatin–riboflavin films. Antimicrobial nanoemulsion (NE) (0.5, 0.75, 1% v/v) was incorporated into crosslinked films and applied to fresh beef. The 1% NE film exhibited the strongest antimicrobial effect, extending shelf-life by 20 days. In vitro release study confirmed Fickian diffusion behavior in the 1% NE film. This study also investigated the synergy between 1% NE film and three different types of modified atmosphere packaging (MAP) on the microbiological and physicochemical properties of beef for 26 days. The best results were achieved with 1% NE film under MAP1 and MAP2, which preserved meat redness and prevented lipid oxidation, extending the shelf-life up to 26 days. Therefore, UV-C irradiation-induced crosslinked bioactive film combined with high-oxygen MAP offers a promising solution for prolonging the shelf-life of beef.

Fabricating Antibacterial Powders from Olive Oil-In Water Emulsions Stabilized by Sour Cherry-Derived Hemicellulose and Pectin Crystalline Structures

Fabricating Antibacterial Powders from Olive Oil-In Water Emulsions Stabilized by Sour Cherry-Derived Hemicellulose and Pectin Crystalline Structures

Electric Demulsification Membrane Technology for Confined Separation of Oil-Water Emulsions.

Demulsification technology for separation of oil-water (O/W) emulsions, especially those stabilized by surfactants, is urgently needed yet remains highly challenging due to their inherent stability characteristics. Electrocoalescence has emerged as a promising solution owing to its simplicity, efficacy, and versatility, yet hindered by substantial energy consumption (e.g., >50 kWh/m3) along with undesirable Faradic reactions. Herein, we propose an innovative electric demulsification technology that leverages conductive membrane microchannels to confine oil droplets from the oil-water emulsion for achieving high energy-efficient coalescence of oil droplets. The proposed system reduces the required voltage down to 12 V, 2 orders of magnitude lower than that of conventional electrocoalescence systems, while achieving a similar separation efficacy of 91.4 ± 3.0% at a low energy consumption (3 kWh/m3) and an ultrahigh permeability >3000 L/(m2·h·bar). In situ fluorescence microscopy combined with COMSOL simulations provided insight into the fundamental mechanistic steps of an electric demulsification process confined to membrane microchannels: (1) rapid electric-field redistribution of oil droplet surfactant molecules, (2) enhanced collision probability due to confined oil droplet concentration under dielectrophoretic forces, and (3) increased collision efficacy facilitated by the membrane pore structure. This strategy may revolutionize the next generation of demulsification and oil-water separation innovations.

Diclofenac recovery by means of using Emulsion Liquid Membranes: A possible role of surfactant in the mass transfer process

Emulsion Liquid Membranes (ELM) are a useful method for drug extraction in aqueous solution, as they allow their recovery in a highly concentrated acceptor phase after passing through a membrane phase with a high surface area. The success of this process depends on system formulation and operation conditions. One of the most important aspects in the formulation is the addition of a surfactant that stabilizes the system, which can also participate in the mass transfer process. Recently, resistance to mass transfer caused by the use of polymeric surfactants, such as Abil® EM 90, has been reported. To verify this phenomenon observed in previous studies, the effect of various factors on the recovery of diclofenac (DCF) dissolved in an aqueous medium was analyzed using the ELM technique. The study concluded that using a membrane consisting of Abil® EM 90 (2 % w/V), trioctylamine (5 % w/V), and dodecane, along with a stripping phase formed by NaOH (0.10 mol/L), results in successful DCF removal. When emulsified at 15,000 rpm for 10 minutes at room temperature, it is possible to remove over 99 % of DCF after 15 minutes and recover 18.45 % after 30 min. Furthermore, it was determined that the action of the surfactant is the main cause of the resistance to the passage of DCF to the internal phase and its retention in the organic phase, as had already been observed. This is probably due to strong intermolecular interactions between Abil ® EM 90 and DCF and the formation of a complex and stable interfacial structure, similar to a hydrated bilayer, which favors the rigidity of the interface and keeps the drug trapped. A better understanding of the role surfactants play in the system is essential for the future design of more efficient and stable ELMs. This knowledge will enable the adaptation of the technology to a wider range of processes, including drug recovery. As a result, the maximum benefits of this technology can be fully realized.

Evaluation of Emulsification Techniques to Optimize the Properties of Chalcone Nanoemulsions for Antifungal Applications

Background/Objectives: Nanoemulsions (NEs) possess properties that enhance the solubility, bioavailability and therapeutic efficacy of drugs. Chalcones are compounds known for their antifungal properties. In this study, we evaluated different emulsification techniques to create alginate nanoemulsions containing chalcone (1E,4E)-1,5-bis (4-methoxyphenyl) penta-1,4-dien-3-one (DB4OCH3). Our goal was to develop an antifungal formulation targeting Candida albicans strains. Methods: Ultrasound and ultrasound combined with high-speed homogenization techniques were used to prepare alginate-stabilized nanoemulsions. Particle size, zeta potential and encapsulation efficiency were evaluated. Additionally, in vitro release studies were conducted. Results: The combined emulsification technique produced stable nanoparticles with high encapsulation efficiency and antifungal activity, with a minimum inhibitory concentration of 8.75 μg/mL for the nanoemulsions compared to 312 µg/mL for free DB4OCH3. NEs’ effectiveness can be attributed to their ability to form nanodroplets efficiently, facilitating the solubilization of the chalcone in the oily phase. The particle size varied between 195.70 ± 2.69 and 243.40 ± 4.49 nm, with an increase in chalcone concentration leading to larger particle sizes. The zeta potential showed values from −91.77 ± 5.58 to −76.90 ± 4.44 mV. The UHS-7 sample exhibited an encapsulation efficiency of 92.10% ± 0.77, with a controlled in vitro release of 83% after 34 h. Molecular docking simulations showed that the aromatic nature of DB4OCH3 resulted in the formation of apolar interactions with aromatic residues located in the active site of the TMK, as observed in their respective co-crystallized inhibitors, within an affinity energy range that enables optimum specificity of the ligand for these two pathways. Pharmacokinetic analyses indicated high passive cell permeability and low hepatic clearance, and phase I metabolism reduces its oral bioavailability and metabolic stability, suggesting a promising active ingredient as an oral drug with control of the daily oral dose administered. Conclusions: The combined nanoemulsification technique led to the formation of finely dispersed nanodroplets that favored the solubilization of the chalcone in the oil phase, which led to a better performance in the antifungal properties. DB4OCH3 shows promise as an oral drug with controlled dosing.

Multifunctional highly conductive cellulose nanopaper with ordered PEDOT:PSS alignment enabled by external surface area-promoted phase separation

Integrating cellulose, the most abundant biopolymer on Earth, with PEDOT:PSS, the most commercially available conducting polymer, can create multifunctional conductive nanopapers for sustainable electronics. However, conventional PEDOT:PSS/cellulose composites often exhibit limited conductivity, primarily due to the random distribution of PEDOT and the aggregation of PSS within the cellulose matrix. Herein, we introduce a confined phase separation approach that leverages the inherent physical characteristics of the cellulose substrate to enhance the performance of these composites. By systematically investigating the influence of the external surface area of nanocellulose on PEDOT:PSS coverage and composition evolution, we demonstrate that a higher external surface area ensures uniform PEDOT:PSS coating on nanocellulose networks and facilitates effective PSS removal during secondary doping. This process enhances phase separation and promotes ordered alignment of PEDOT chains along nanocellulose, resulting in an electrical conductivity of up to 252 S cm−1. Such highly conductive nanopapers exhibit exceptional performances in supercapacitors and electromagnetic shielding, achieving an ultrahigh specific electromagnetic shielding effectiveness of 33,122 dB cm2 g⁻1 at only 6 μm thickness. Our study highlights the critical role of cellulose substrate selection at the nanoscale and elucidates the interactions within conducting polymers, offering a promising pathway for developing high-performance, sustainable electronics.

Egg Yolk, a Multifunctional Emulsifier: New Insights on Factors Influencing and Mechanistic Pathways in Egg Yolk Emulsification

Egg yolk is a highly effective natural emulsifier used in various food products. Its emulsifying properties are influenced by food product chemical conditions, and processing methods. Nevertheless, to effectively utilize egg yolk in food products, a more comprehensive understanding of these factors is crucial. This review discusses recent developments regarding how factors like pH, ionic strength, thermal treatments, enzymatic treatments, and novel non-thermal treatments affect egg yolk emulsifying properties. It also explores the underlying mechanisms involved in egg yolk emulsification. Food products involve different ingredients leading to varying pH values and ionic strength, which affect egg yolk protein adsorption and emulsion stability. Processing steps like thermal treatment can damage egg yolk proteins, reducing their emulsifying capabilities and leading to unstable products. Incorporating sugar, salt, and amino acids can enhance egg yolk’s resistance to heat and preserve its ability to form stable emulsions. As an alternative to thermal treatment, non-thermal techniques such as high-pressure processing and high-intensity ultrasound can be employed to preserve egg yolk. Furthermore, forming egg yolk–polysaccharide complexes can enhance egg yolk emulsifying properties. These advancements have facilitated the creation of egg yolk-based products such as high internal phase Pickering emulsions (HIPEs), low-fat mayonnaise, and egg yolk gels. A comprehensive understanding of the emulsifying mechanisms and factors involved in egg yolk will be instrumental in improving food quality and creating novel egg yolk-based products.

The synergistic effect of α-tocopherol and phloretin-loaded nanoemulsions on improvement of the stability, antioxidant, and tyrosinase inhibitory potentiality.

The purpose of this study was to prepare and evaluate the formulation of nanoemulsions (NEs) to encapsulate phloretin (PT) to improve its stability, antioxidant, and tyrosinase inhibitory competence. The aim of this study was to improve the stability, antioxidant, and tyrosinase inhibitory effects of PT via NEs. The formulations were prepared using low energy emulsification method for PT-VE-NEs, α-tocopherol (Vitamin E) and medium chain triglycerides (MCT) were used as the oil phase, and Tween 60 was used as the emulsifier and PEG-400 as the co-emulsifier. The droplet size and zeta potential of oil-in-water NEs were evaluated using dynamic light scattering. The PT-VE-NEs were also characterized by transmission electron microscopy and Fourier transform infrared spectroscopy. The mean droplet diameter was 14.85±0.14nm, with a zeta potential of -2.47±0.51mV. Fourier transform infrared spectroscopy revealed the formation of molecular interactions in the NEs formulations. PT-VE-NEs size was maintained the same during the in vitro digestion study. The particle size of PT-VE-NE remained stable during in vitro digestion. The addition of VE significantly improved the antioxidant, tyrosinase inhibitory effects, as well as thelion and physical stability of PT-VE-NE. The results revealed that NEs is a promising strategy to improve the functionality and stability of PT and VE. PT-VE-NEs will be applied for the preservation of fruits.

Indigo alleviates psoriasis through the AhR/NF-κB signaling pathway: an in vitro and in vivo study.

Psoriasis is a chronic inflammatory skin disease. A strong association between the AhR/ NFκB axis and the inflammatory response in psoriasis. Indigo (IDG) has demonstrated significant anti-inflammatory properties. This study aimed to assess the anti-psoriatic efficacy of IDG while investigating the underlying mechanisms involved. In the in vitro experiments, cell viability was assessed using the CCK-8. qRT-PCR was employed to measure the mRNA levels of NF-κB, TNF-α, IL-1β, AhR, and CYP1A1. Western blotting was conducted to examine alterations in cytoplasmic and nuclear AhR protein levels. Additionally, an IDG nanoemulsion (NE) cream was prepared for the in vivo experiments. A psoriasis-like skin lesion mice model was induced using IMQ (62.5 mg/day for 7 days). The severity of psoriasis was evaluated using PASI, and skin lesions were scored while epidermal thickness was assessed via HE staining. The expression of inflammatory markers, including IL-6, IL-13, IL-17A, MCP-1, and TNF-α, was detected in skin lesions using Luminex. The levels of CYP1A1, p65, and p-p65 proteins were determined by Western blotting. LPS stimulation significantly elevated TNF-α, IL-6, and NF-κB mRNA levels, which were notably reduced by IDG treatment. Additionally, IDG significantly enhanced the expression of AhR and CYP1A1 mRNA. Further investigation revealed that IDG facilitated AhR translocation from the cytoplasm to the nucleus. In the IMQ-induced psoriasis-like mouse model, IDG NE substantially ameliorated the severity of skin lesions. Moreover, IDG NE treatment reduced the upregulation of inflammatory cytokines such as IL-6, IL-17A, MCP-1, and TNF-α in IMQ-induced skin lesions. It was also observed that IDG NE treatment increased CYP1A1 protein expression while inhibiting p65 and p-p65 protein expression. IDG emerges as a promising treatment for psoriasis, demonstrating effective therapeutic outcomes. Its mechanism of action is likely linked to the modulation of the AhR/NFκB signaling pathway.

Encapsulation of Liquids via Polymer Precipitation in Emulsions

ABSTRACTMicroencapsulation strategies enable the confinement of sensitive active materials in a protective shell, giving capsules with applications across pharmaceuticals, foodstuffs, agriculture, textiles, cosmetics, and energy storage. Among the different approaches, the soft template encapsulation method is a widely used technique that leverages emulsions as templates and forms spherical microcapsules with a liquid core and polymeric shell. Within the emulsion template umbrella, interfacial polymerization, phase internal phase separation, and polymer precipitation can all be used. The main limitation of interfacial polymerization is that the core will inevitably contain impurities such as residual monomers, which can affect the performance of the encapsulated material. This is especially relevant when performance efficiency strongly depends on its pristine composition. In this perspective, we focus on polymer precipitation soft‐template strategies for capsule formation, and the complementarity of this approach to the more widely used interfacial polymerization. Polymer precipitation strategies enable the encapsulation of sensitive cores (or payloads) and can include those that are viscous, hygroscopic, and reactive.