Oil-water Interface Research Articles

Hydrophobic modification of biomass chitosan for treatment of oily wastewater and its demulsification mechanism

Traditional demulsifiers are commonly produced using raw materials like ethylene oxide and propylene oxide, which deplete significant petroleum resources and involve hazardous and complex manufacturing processes. In this investigation, a hydrophobically modified chitosan (HMC) was synthesized by grafting dodecyl diethanolamine onto natural chitosan to facilitate the separation of O/W emulsions. Characterization of HMC was conducted using Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance hydrogen spectroscopy (1H NMR) and scanning electron microscopy (SEM). The demulsification efficacy of HMC was assessed through a bottle test in an O/W emulsion containing 0.2 % crude oil. Results showed that at a HMC dosage of 40 mg/L, the light transmission (WT) and oil removal efficiency (WR) of the resulted water phase were 93.4 ± 0.8 % and 99.8 ± 0.1 %, respectively. Furthermore, the competitive adsorption between natural surfactants and HMC at the interface was investigated using interfacial tension (IFT), three-phase contact angle (CA), droplet coalescence time (CTA), and interfacial film substitution. A potential demulsifying mechanism was also proposed, emphasizing HMC’s hydrophilic core and dispersed hydrophobic alkyl chains that enable rapid diffusion to the oil–water interface, replacing interfacial active components to induce demulsification by destabilizing the composite film. The advantages of HMC demulsifier over commercial demulsifiers lie in its superior environmental benefits, diverse range of sources, higher efficiency, and outstanding demulsification performance.

Influence of synergistic/competitive interactions of nonionic emulsifiers and proteins on the foam stability of whole egg liquids: Based on air-water and oil-water dual interface perspectives

Nonionic emulsifiers (NE) are widely used in sponge cakes because they can effectively improve the foaming properties of whole egg liquids (WEL). The WEL are rich in protein, lipids and water, forming air-water and oil-water interface during whipping and foaming. However, different NE plays different roles in the interface. No systematic study has been conducted on the stabilization mechanism of WEL by NE. This study first investigated the effect of different NE on the foaming properties of WEL. It was found that WEL with sucrose ester-9 (SE-9) had the highest foam stability (FS) (92.52%), while that with Tween 80 had the lowest (75.55%). It was found that this was related to the higher interfacial protein substitution ability of Tween 80. Next, free triglyceride content and CLSM analysis confirmed that NE promoted the formation of more oil-water interfaces in the foam. Moreover, NE could improve FS by reducing droplet size and increasing viscosity. Finally, the higher surface activity of NE than proteins was demonstrated by interfacial adsorption kinetics and dilatation rheology. SE-9 interacted with proteins at the air-water interface to enhance interfacial rigidity, whereas adsorption of Tween 80 led to a decrease in the rearrangement rate. The results also showed that the formation of oil-water interfacial films was dominated by the adsorption of NE. This study illustrated how different NE stabilized air-water and oil-water interfaces, and the effect of synergistic/competitive interactions with proteins on the stability of the interfaces. This will provide new insights into the stability regulation of WEL foam.

Equilibrium and self-assembly of Janus particles at liquid-liquid interfaces for the film formation

This article investigates the equilibrium arrangement, self-assembly process, and subsequent curing of amphiphilic snowman-shaped Janus particles at the oil-water interface. The independent Janus particles are in vertical equilibrium state and the contact position of the oil-water interface is at the largest cross section of the particle’s hydrophobic phase. Under the effect of the surface tension and the adsorption of materials, Janus particles may form particle combinations including the particle pairs and the particle triangle, whose inner and outer sides have the liquid surface exhibiting completely opposite contact angles. Particle combinations form stable parallel double-chain structures with diverse shapes after the self-assembly process. However, the single Janus particles attain a state of mechanical equilibrium under the influence of surrounding particles, enabling them to assemble into regular array structures. The relationship of interfacial tension coefficient between phases can be changed by adjusting the oil-water system, which leads to variations in the self-assembly speed and the final arrangement results. The thin-film with uniformly distributed vertical particles is achieved by replacing the underlying deionized water with a curing agent. Based on the understanding of the interactions between irregularly shaped Janus particles at the oil-water interface, it will be convenient to achieve the controllable self-assembly and widely applications of these particles.

Interfacial Cooperative Assembly of Surfactants and Opposite Wettability Nanoparticles Stabilizes Water-in-Oil Emulsions at High Temperature.

Pickering emulsions have promising applications in the development of unconventional oil and gas resources. However, the high-temperature environment of the reservoir is not conducive to the stabilization of Pickering emulsions. In addition, the preparation of Pickering emulsions under low-energy emulsification and low-concentration emulsifier conditions is a difficult challenge. Here, we report a high-temperature resistant water-in-paraffin oil Pickering emulsion, which is synergistically stabilized by polyglycerol ester (PGE) and nanoparticles with opposite wettability (lipophilic silica and hydrophilic alumina). This emulsion can be prepared under mild stirring (500 rpm) conditions and can be stable at 140 °C for at least 30 days. The synergistic effects of surfactant, silicon nanoparticles (MSNPs) with different wettability, and alumina nanoparticles (AONPs) on the stability of both emulsions and water-oil interfacial membranes were investigated through bottle experiments, cryogenic scanning electron microscopy (cryo-SEM), optical microscopy, fluorescence microscopy, etc. The results showed that both hydrophobic MSNPs and hydrophilic AONPs are adsorbed together at the water-oil interface to stabilize the W/O emulsion, which can be prepared by 500 rpm stirring. The stability of emulsions strongly depends on the wettability of MSNPs, and the MSNP with moderate hydrophobicity (for example, aqueous phase contact angle of 136°) makes the emulsion exhibit the highest stability against aggregation and settling at elevated temperatures. The emulsion stabilization mechanism was revealed in terms of the adsorption capacity of the surfactant by MSNPs, the adsorption morphology and desorption energy of nanoparticles at the water-oil interface adsorption layer, and emulsion rheology. These findings demonstrate a novel and simple strategy to prepare Pickering W/O emulsions with high-temperature stability at low shear strength.

Effect of protein oxidation on the structure and emulsifying properties of fish gelatin

This study aimed to investigate the effect of oxidation on fish gelatin and its emulsifying properties. Fish gelatin was oxidized with varying concentrations of H2O2 (0–30 mM). Increased concentrations of the oxidant led to a decrease in amino acids in the gelatin, including glycine, lysine, and arginine. Additionally, the relative content of ordered secondary structure and triple helix fractions decreased. Zeta potential decreased, while particle size, surface hydrophobicity, and water contact angle increased. Regarding emulsifying behavior, oxidation promoted the adsorption of gelatin to the oil–water interface and reduced interfacial tension. With increased degrees of oxidation, the zeta potential and size of the emulsion droplets decreased. The oxidized gelatin exhibited better emulsifying activity but worse emulsifying stability. Based on these results, a mechanism for how oxidation affects the emulsifying properties of gelatin was proposed: the increase in gelatin’s hydrophobicity and the decrease in triple helix structure induced by oxidation reduced the interfacial tension at the oil–water interface. This promoted protein adsorption at the oil–water interface, allowing the formation of smaller oil droplets and enhancing gelatin’s emulsifying activity. However, the decrease in electrostatic repulsion between emulsion droplets and the decrease in solution viscosity increased the flocculation and aggregation of oil droplets, ultimately weakening the emulsifying stability of gelatin.

Interaction mechanism and factors influencing dynamics of rock-heavy oil-chemical agent interface

The interactions among the rock, oil, and chemical agent are critical for oil recovery. However, the mechanisms underlying this synergistic effect remain unclear. Therefore, this study used custom-made experimental methods to analyze these interactions and behavior of heavy oil on rock surfaces and elucidate the micro-interaction mechanism of the liquid–solid interface. Oil adhesion, flow, and deformation were studied via experiments on oil spreading, oil film emulsification, oil film shrinkage, and oil droplet peeling and deformation. Moreover, the contributions of oil diffusion on rock surface and flow through porous media to oil spread dynamics were detailed for the first time. The influence of the oil flow in porous media on oil recovery and the influencing factors were also studied. Furthermore, the effects of the rock–oil–water interface on the emulsification, shrinkage, and peeling of oil film were studied via chemical agent–oil film interactions. The main mechanisms underlying the effects of chemical agents on heavy oil flow were elucidated. Finally, the morphologies of the oil droplets under weak buoyancy were studied. The degree of deformation of oil droplets was evaluated to analyze the effect of chemical agents on the oil–water interface and factors influencing this process. Therefore, this study offers insights into the oil recovery process by analyzing heavy oil flow through porous media and the effects of chemical agents on rock surfaces and oil–water interfaces and lays the groundwork for chemical agent optimization to enhance oil recovery.

Adjusting the hydrophobicity of recombinant microgels to improve interfacial activity: Using a promising pickering emulsion stabilizer with a dense cubic structure

Developing recombinant microgels (RMs) with high mechanical and anti-coalescence properties provides a safe and economical method for constructing uniform and stable Pickering emulsions. Previously, we prepared RMs based on polysaccharides using freeze–thaw cycles, displaying excellent stability. Because RMs can be formed between polysaccharides, we studied whether they can be formed between polysaccharides and proteins for preparing Pickering emulsions. Therefore, we report a heat-induced gelation method to generate RMs with bovine serum albumin (BSA) and κ-carrageenan (KC). Owing to heat-induced treatment (90 °C), the high hydrophilicity of KC could be regulated by the exposed hydrophobic groups of BSA, and the system rapidly gelated after cooling (−18 °C) to obtain a dense recombinant structure. The TPA and SEM results further demonstrated that the RMs with a BSA:KC ratio of 1:2 have a typical cubic structure (0.93 μm) and excellent gel strength. RMs adsorbed at the oil–water interface to form non-covalent binding layers, which improved interfacial activity and reduced interfacial tension (95.10°) to obtain more uniform and stable Pickering emulsions. The above results indicate that synthesizing RMs provides a feasible method for constructing uniform and stable Pickering emulsions with low oil content, these are similar to high internal phase emulsions with semi-solid rigid structures.

Self-dispersion of photocatalysts at oil-water interface accelerates H2O2 production and separation

Enhancing the efficiency of photocatalytic charge transfer for H2O2 production and in situ separation of H2O2 from aqueous suspension are crucial, especially when sacrificial agents are involved, for the advancement of this environmental-friendly process. In this study, we propose that the production and separation of H2O2 can be significantly enhanced at a self-assembled tri-phase system (water/photocatalyst/benzyl alcohol) compared to the suspension system. To prove this, we have employed titania nanotube (TNT) as a representative photocatalyst with efficient oxygen adsorption and modified it with organic ligand (octadecyl phosphate, OPA) and nickel species to modulate its hydrophobicity and dispersity at the interface, resulting in improved H2O2 yield. The modified TNT photocatalyst demonstrates efficient H2O2 production reaching a concentration of 5.1 mM after 75 mins under optimized conditions and an initial rate of 7500 μmol/g/h within first 6 h that even exceeding reported noble metals modified TiO2 photocatalysts. This enhanced activity is attributed to multiple effects including homogeneous dispersion of photocatalyst at the oil-water interface, efficient O2 adsorption and transfer, separated redox reactions at different phases, timely diffusion of H2O2 into bulk aqueous solution, and potential solvent-induced polarization effect on charge transfer, which result from the special oil-water interface that stabilizing photocatalysts and inducing photocatalytic O2 reduction. As proof-of-concept demonstrations show successful photosynthesis of H2O2 using natural solar light followed by utilizing the generated pure H2O2 solution for bacteria inactivation, indicating that interfacial photocatalytic systems offer promising potential for green H2O2 synthesis and application.

The impact of structural properties on the absorption of hen egg-white ovotransferrin with or without Fe3+ at the air/oil-water interface

This study investigated the impact of structural changes (particle size, potential, hydrophobicity, circular dichroism spectra) in ovotransferrin with and without Fe3+ (holo-OVT and apo-OVT) on their interfacial behaviors. Holo-OVT exhibited greater diffusion, penetration, and rearrangement rates at the oil-water interface, whereas apo-OVT was detected at the air-water interface owing to the reduced hydrophobicity of air phase. Reduced hydrophobicity of both the protein (apo-OVT) and the dispersed phase (oil) leads to shorter lag periods. As for the interfacial film, holo-OVT formed denser but thinner films than those formed by apo-OVT at both interfaces, as confirmed by larger viscoelastic modulus, reduced film thickness, and lower Gibbs surface excess. These findings were likely attributable to the greater structural rigidity of holo-OVT presented with significant decreases in hydrophobicity index (432.20) than apo-OVT (522.40). Ultimately, holo-OVT exhibited significant improvements in foaming and emulsifying stability than apo-OVT.

Desmodium intortum (Mill.) Urb. Protein Isolate Aggregates as Pickering Stabilizers: Physicochemical Characteristics and Emulsifying Properties.

This work aimed to investigate the feasibility of fabricating Pickering emulsions stabilized by Desmodium intortum protein isolate (DIPI) aggregates. The DIPI aggregates were formed using heat treatment, and the effects of ionic strength and pH on their properties were investigated. The heat-treated protein exposes its hydrophobic groups due to structural damage, resulting in rapid aggregation of the protein into aggregates with a size of 236 nm. The results showed that the aggregates induced by ionic strength had larger particle size and higher surface hydrophobicity and partial wettability. Moreover, this study explored effective strategies for bolstering Pickering emulsion stability through optimized DIPI aggregate concentration (c) and oil fraction (ø). The DIPI Pickering emulsion (DIPIPE) formed at c = 5% and ø = 0.7 was still highly stable after 30 days of storage. As confirmed by laser confocal microscopy, DIPI aggregates could be adsorbed onto the oil-water interface to form a network structure that could trap oil droplets in the network. Collectively, the Pickering emulsion stabilized by DIPI aggregates exhibited excellent stability, which not only deeply utilizes the low-value protein resources in the Desmodium intortum for the first time, but also demonstrates the potential of DIPI for the bio-based field.

Impact of nanoparticle movement on oil mobilization: Particles adsorbed at the oil–water interface versus particles dispersed in bulk fluid

Active colloid particles have been used in many fields due to their good performance in enhancing mass transport or modifying interfacial energy. Previous studies have shown that both nanoparticles adsorbed at oil–water interface and those dispersed in bulk fluid could enhance oil recovery during the oil production process. It is challenge to directly compare these results and clarify the effect of nanoparticle’s location on oil detachment from rock surface because different kinds of nanofluids were used in those work. Herein, the oil mobilization performance by nanoparticles adsorbed at oil–water interface and dispersed in the bulk phase were investigated from the pore-scale to core-scale by using one material. Two fluorescent quantum nanodots with different affinities for oil and water phases were synthesized using the same materials but with different compositions and solvents. Their locations were observed under the laser confocal microscopy. The nanoparticles adsorbed at the oil–water interface not only presented a lower interface tension, but also demonstrated a notable capability to change the wettability from oil-wet to water-wet due to its strong tendency to rock surface. The particles-laden interface can also increase the stability and shear viscosity of formed emulsions. Furthermore, it featured a larger swept area of 6.6 % in microfluidic flooding and a higher displacement efficiency of 1.7 % in the core flooding experiments. All these findings indicate that the particle-adsorbed at the oil–water interface is more favorable for enhanced oil recovery.

Study on the interactions and interfacial behaviors of cellulose nanocrystal/β-lactoglobulin complexes for pickering emulsions

Pickering emulsions stabilized by polysaccharides and protein complexes have attracted increasing attention. Exploring their interfacial activities and adsorption behaviors at the oil–water interface is of great significance for deepening our understanding of the emulsification mechanism and improving the properties of polysaccharide/protein-stabilized emulsions. Here, cellulose nanocrystals (CNCs) with rod-like structures and spherical β-lactoglobulin (β-LG) proteins were selected as representative stabilizers. We initially investigated the interaction between the 2 at pH 2.0–7.0 through a multiscale approach. Then, oil–water interfacial tension tests were used to assess the interfacial activities of CNCs and β-LG, revealing that β-LG exerted primary influence over the interfacial behavior in their complexes. Meanwhile, quartz crystal microbalance with dissipation was used to monitor the interfacial adsorption behaviors of CNCs, β-LG, and CNC/β-LG complexes, demonstrating that the interfacial layer formed by the CNC/β-LG complexes on the oil film (∼696.7 ng/cm2) was thicker and more stable compared with that formed by individual CNCs (∼48.4 ng/cm2) or β-LG (∼87.1 ng/cm2). Finally, we applied the CNC/β-LG complexes as stabilizers in Pickering emulsions and the emulsions prepared with the complexes at concentrations above 0.8 wt% exhibited storage stability for up to 28 d which confirmed their exceptional emulsifying ability and practical value. This study provides profound insights into the interfacial behavior of polysaccharide–protein complexes in Pickering emulsions and is expected to facilitate the design of novel food-grade emulsifiers.

Microscopic Aggregation and Film‐Forming Characteristics of Lubricant Additives on Oil–Water Interface: MD Simulation and Experiments on Water Separability

Microscopic Aggregation and Film‐Forming Characteristics of Lubricant Additives on Oil–Water Interface: <scp>MD</scp> Simulation and Experiments on Water Separability

Experimental study on in-situ emulsification of heavy oil in porous media

Under the strategic goal of “dual-carbon”, reducing oil viscosity by in-situ emulsification using chemical method has become a new direction for high-efficiency and low-carbon development of heavy oil reservoirs. This technology can transform the originally immovable heavy oil into movable dispersed oil droplets through in-situ emulsification, and thus enhances heavy oil recovery. However, there is still a lack of sufficient understanding about the characteristics and influencing laws of in-situ emulsification of heavy oil in porous media. So, this paper carried out experimental studies on in-situ emulsification and influencing factors for heavy oil in porous media. The results show that, due to the transport and adsorption loss of viscosity reducer in porous media, the emulsification area expands gradually from the inlet to the outlet. At the same sampling position, with the increase of injection volume, the dispersed oil droplet size decreases, the distribution density increases, and the color of produced liquid changes from light yellow to dark brown. Under the same injection volume, the closer to the outlet, the smaller the particle size of the dispersed oil droplets and the higher the distribution density, which is resulted from the shearing effect of the porous media. With the increase of injection rate, the hydrodynamic shear effect is enhanced, so the in-situ emulsification of heavy oil starts earlier and the emulsification oil ratio curves have a higher slope and distribute more densely. With the increase of agent concentration, the adsorbed number of viscosity reducer molecules on the oil–water interface is increased, making it easier to emulsify the remaining oil. With the increase of pre-conversion oil recovery, the remaining oil in the porous media is more dispersed and the oil–water contact surface increases, so the emulsification is easier and the percentage of dispersed oil droplets in the produced oil phase increases. The research results based on sampling analysis deepen our understanding on in-situ emulsification of heavy oil in porous media, which provides valuable reference for designing suitable viscosity reducer agent and effectively enhancing heavy oil recovery in the future.

Highly Hydrophilic TiO2 Nanoparticles as Stabilizers of Pickering Emulsions with Photosensitive Lipophilic Compounds: Synthesis and Application.

Pickering emulsions are a very promising system for encapsulating and photoprotecting active ingredients. The highest photoprotection efficiency can be achieved when bare TiO2 nanoparticles are used as stabilizers. However, the main problem when using highly hydrophilic TiO2 nanoparticles is their inability to adsorb at the oil-water interface. Here, we developed emulsions stabilized by bare, highly hydrophilic TiO2 nanoparticles for the encapsulation and photoprotection of active lipophilic compounds. Emulsion stabilization occurs due to the formation of hydrogen bonds between hydroxyl groups on the particle surface and the carbonyl groups of the oil molecules. The stability and rheological properties of emulsions are explained by the properties of the initial hydrosols. The resulting Pickering emulsions demonstrated effective UV protection of α-lipoic acid. Our results pave the way for the formulation of Pickering emulsions with a widely used cosmetic oil and show for the first time the possibility of photoprotection of a lipophilic active substance using unmodified TiO2 nanoparticles.

Cholic Acid/Glutathione-Assembled Nanofibrils for Stabilizing Pickering Emulsion Biogels.

Achieving the delicate balance required for both emulsion and gel characteristics, while also imparting biological functionality in gelled emulsions, poses a significant challenge. Herein, Pickering emulsion biogels stabilized is reported by novel biological nanofibrils assembled from natural glutathione (GSH) and a tripod cholic acid derivative (TCA) via electrostatic interactions. GSH, composed of tripeptides with carboxyl groups, facilitates the protonation and dissolution of TCA compounds in water and the electrostatic interactions between GSH and TCA trigger nanofibrillar assembly. Fibrous nuclei initially emerge, and the formed mature nanofibrils can generate a stable hydrogel at a low solid concentration. These nanofibrils exhibit efficient emulsifying capability, enabling the preparation of stable Pickering oil-in-water (O/W) emulsion gels with adjustable phase volume ratios. The entangled nanofibrils adsorbed at the oil-water interface restrict droplet movement, imparting viscoelasticity and injectability to the emulsions. Remarkably, the biocompatible nanofibrils and stabilized emulsion gels demonstrate promising scavenging properties against reactive oxygen species (ROS). This strategy may open new scenarios for the design of advanced emulsion gel materials using natural precursors and affordable building blocks for biomedical applications.

Bottle test technique for separating water-in-sunflower oil emulsion under an application of electric field stabilised by surfactant and hydrolysed polyacrylamide

The efficacy of separating water-in-oil emulsions depends on the stability of the emulsion, which is influenced by the interaction of the polymer and surfactant at the oil–water interface. We examined the role of hydrolysed polyacrylamide and surfactants on the stability of water-in-oil emulsions. The effects were investigated by implementing bottle tests (BT) and electrocoalescence bottle tests (EBT) using various types of surfactants over a wide range of concentrations. For a high volume fraction (10% v/v) of emulsion, the BT study showed 80% of separation in a short duration. At a small volume fraction (2% v/v), efficient separation was achieved by applying an electric field. These studies were further extended to a hybrid mode of operation, combining 1 kV/cm, non-uniform DC electrical fields at a temperature of 60 °C, to achieve maximum separation efficiency of up to 91% within 10 min for deionised water when the volume fraction of water in the emulsion was 2%. Under the same conditions, we observed an impressive 88% separation for surfactant and polymer-stabilised emulsions. HPAM does not affect interfacial tension due to its lack of amphiphilic character. However, it significantly increases the viscosity of the dispersed phase by forming a network that restricts coalescence, thereby affecting the separation rate. Surfactants enhance stability by reducing interfacial tension (IFT) and forming a protective layer around the droplet. The findings provide valuable insights for optimising separation processes using the synergy of the heating and electric fields. The study successfully and efficiently separates oil and water, even when dealing with challenging emulsions containing polymers and surfactants, by combining heating and electrical methods.

Advancing oil-water separation: Design and efficiency of amphiphilic hyperbranched demulsifiers

Hypothesis: An innovative strategy for designing high-performance demulsifiers is proposed. It hypothesizes that integrating mesoscopic molecular simulations with macroscopic physicochemical experiments can enhance the understanding and effectiveness of demulsifiers. Specifically, it is suggested that amphiphilic hyperbranched polyethyleneimine (CHPEI) could act as an efficient demulsifier in oil–water systems, with its performance influenced by its adsorption behaviors at the oil–water interface and its ability to disrupt asphaltene-resin aggregates.Experiments: Several coarse-grained models of oil–water systems, with CHPEI, are constructed using dissipative particle dynamics (DPD) simulation. Following the insights gained from the simulations, a series of CHPEI-based demulsifiers are designed and synthesized. Demulsification experiments are conducted on both simulated and crude oil emulsions, with the process monitored using laser scanning confocal microscopy. Additionally, adsorption kinetics and small angle X-ray scattering are employed to reveal the inherent structural characteristics of CHPEI demulsifiers.Findings: CHPEI demonstrates over 96.7 % demulsification efficiency in high acid-alkali-salt systems and maintains its performance even after multiple reuse cycles. The simulations and macroscopic experiments collectively elucidate that the effectiveness of a demulsifier is largely dependent on its molecular weight and the balance of hydrophilic and hydrophobic groups. These factors are crucial in providing sufficient interfacial active functional groups while avoiding adsorption sites for other surfactants. Collaborative efforts between DPD simulation and macroscopic measurements deepen the understanding of how demulsifiers can improve oil–water separation efficiency in emulsion treatment.

A natural protein-lipid co-assembly as efficient Pickering emulsifier from egg yolk sphere microgel prepared via high-pressure homogenization

Egg yolk sphere is a kind of natural colloidal histological structure formed by the co-assembly of a large number of proteins and lipids, which has the dual functions of hydrophilic and lipophilic for application in emulsion. In this study, egg yolk sphere microgels (EYSMs) were prepared by high pressure homogenization (HPH) technique at various pressures (0–90 MPa) and used as Pickering emulsifiers for emulsification to obtain oil-in-water emulsions with an oil-water ratio of 11:9. The microscopic morphology, structure, and physicochemical properties of EYSMs were analyzed. The results showed that EYSMs obtained at 60 MPa (60-EYSMs) exhibited superior emulsifying properties with an emulsifying activity index (EAI) of 2.8 m2/g and an emulsifying stability index (ESI) of 356.6 min, resulting in enhanced storage stability of the emulsion for 30 d. The HPH treatment decreased the lipid content in EYSMs while creating a more homogeneous protein-lipid arrangement, which provided EYSMs with balanced hydrophilic and hydrophobic sites to improve emulsifying properties. Furthermore, the free sulfhydryl groups and hydrophobic moieties exposed by HPH promoted -S-S- formation on the EYSMs surface, promoting the increase in surface hydrophobicity and emulsifying ability. The confocal laser scanning microscopy (CLSM) and cryogenic scanning electron microscopy (cryo-SEM) revealed that the EYSMs adsorbed at oil-water interface and formed an intercross-linked spatial three-dimensional network structure, which worked as a physical barrier to the stable emulsion formation. This study introduces a novel research concept and delves into the emulsification mechanism of protein-lipid composite particles, offering a fresh insight for the development and utilization of emulsifiers.

Interfacially Self-Assembled Mutifunctional Protein Thin Films for Accelerated Wound Healing.

The design of mutifunctional protein films for large-area spatially ordered arrays of functional components holds great promise in the field of biomedical applications. Herein, interfacial electrostatic self-assembly was employed to construct a large-scale protein thin film by inducing electrostatic interactions between three bovine serum albumin (BSA)-coated nanoclusters and cetyltrimethylammonium bromide (CTAB), leading to their spontaneous organization and uniform distribution at the oil-water interface. This protein film demonstrated excellent multienzyme functions, high antibacterial activity, and pH-responsive drug release capability. Therefore, it can accelerate the wound closure process through a synergistic effect that includes reducing local blood glucose levels, regulating cellular oxidative stress, eradicating bacteria, and promoting cell proliferation.