Controlled assembly of superparamagnetic iron oxide nanoparticle into nanoliposome for Pickering emulsion preparation

There has been a surge in effort in the development of various solid nanoparticles as Pickering emulsion stabilizers in the past decades. Regardless, the exploration of stabilizers that simultaneously stabilize and deliver bioactive has been limited. For this, liposomes with amphiphilic nature have been introduced as Pickering emulsion stabilizers but these nano-sized vesicles lack targeting specificity. Therefore in this study, superparamagnetic iron oxide nanoparticles (SPION) encapsulated within liposomes (MLP) were used as Pickering emulsion stabilizers to prepare pH and magnetic-responsive Pickering emulsions. A stable MLP-stabilized Pickering emulsion formulation was established by varying the MLP pH, concentration, and oil loading during the emulsification process. The primary stabilization mechanism of the emulsion under pH variation was identified to be largely associated with the MLP phosphate group deprotonation. When subjected to sequential pH adjustment to imitate the gastrointestinal digestion pH environment, a recovery in Pickering emulsion integrity was observed as the pH changes from acidic to alkaline. By incorporating SPION, the Pickering emulsion can be guided to the targeted site under the influence of a magnetic field without compromising emulsion stability. Overall, the results demonstrated the potential of MLP-stabilized Pickering emulsion as a dual pH- and magnetic-responsive drug delivery carrier with the ability to co-encapsulate hydrophobic and hydrophilic bioactive.

Liposomes decorated with β-conglycinin and glycinin: Construction, structure and in vitro digestive stability

Liposomes were modified with different proportions of β-conglycinin (7S) and glycinin (11S) to form Lip-7S and Lip-11S. The morphology, interaction and in vitro simulated digestion of liposomes were studied. The particle size of Lip-7S was smaller than that of Lip-11S. When the values of Lip-7S and Lip-11S were 1:1 and 1:0.75, respectively, the ζ-potential had the maximum absolute value and the dispersion of the system was good. The results of multispectral analysis showed that hydrogen-bond and hydrophobic interaction dominated protein-modified liposomes, the protein structure adsorbed on the surface of liposomes changed, the content of α-helix decreased, and the structure of protein-modified liposomes became denser. The surface hydrophobicity and micropolarity of liposomes decreased with the increase of protein ratio, and tended to be stable after Lip-7S (1:1) and Lip-11S (1:0.75). Differential scanning calorimetry showed that Lip-7S had higher phase transition temperature (≥170.5 °C) and better rigid structure. During simulated digestion, Lip-7S (22.5 %) released less Morin than Lip (40.6 %) and Lip-11S (26.2 %), and effectively delayed the release of FFAs. The environmental stability of liposomes was effectively improved by protein modification, and 7S had better modification effect than 11S. This provides a theoretical basis for 7S and 11S modified liposomes, and also provides a data reference for searching for new materials for stabilization of liposomes.

Protection of osteogenic peptides in nanoliposomes: Stability, sustained release, bioaccessibility and influence on bioactive properties

This study prepared osteogenic peptides (OPs) from cod meat by hydrolysis and subsequently encapsulated them in nanoliposomes (NLP) to enhance bioaccessibility. The characterization, stability, controlled release behavior and bioactivity of OPs-loaded nanoliposomes (OPs-NLP) were investigated as well. The highest loading capacity (27.32%) was achieved in NLP loaded with 6 mg/mL of OPs. The particle size, zeta potential, and encapsulation efficiency of OPs-NLP were 70.59 nm, -11.98 mV, and 75.24%, respectively. The interaction between OPs and empty NLP was through hydrogen bonding and hydrophobic. The OPs-NLP showed the greatest stability during storage at 4 °C. The in vitro release profile of OPs from OPs-NLP fitted a one-level kinetic model best. The osteogenic activity of OPs was unaffected by NLP encapsulation, and the bioaccessibility of OPs was notably improved. These findings suggest that OPs-NLP has the potential to be used in functional foods.

A cochleate formulation optimized by D-optimal mixture design enhances oral bioavailability of Revaprazan

A cochleate formulation was developed to enhance the oral bioavailability of revaprazan (RVP). Dimyristoyl phosphatidylcholine (DMPC) liposome containing dicetyl phosphate (DCP) successfully formed a cochleate after treatment with CaCl2, whereas that containing sodium deoxycholate did not. Cochleate was optimised using a D-optimal mixture design with three independent variables-DMPC (X1, 70.58 mol%), cholesterol (X2, 22.54 mol%), and DCP (X3, 6.88 mol%)-and three response variables: encapsulation efficiency (Y1, 76.92%), released amount of free fatty acid at 2 h (Y2, 39.82%), and released amount of RVP at 6 h (Y3, 73.72%). The desirability function was 0.616, showing an excellent agreement between the predicted and experimental values. The cylindrical morphology of the optimised cochleate was visualised, and laurdan spectroscopy confirmed the dehydrated membrane interface, showing an increased generalised polarisation value (approximately 0.5) over small unilamellar vesicle of RVP (RVP-SUV; approximately 0.1). The optimised cochleate showed greater resistance to pancreatic enzyme than RVP-SUV. RVP was released in a controlled manner, achieving approximately 94% release in 12 h. Following oral administration in rats, the optimised cochleate improved the relative bioavailability of RVP by approximately 274%, 255%, and 172% compared to RVP suspension, a physical mixture of RVP and the cochleate, and RVP-SUV, respectively. Thus, the optimised cochleate formulation might be a good candidate for the practical development of RVP.

Effects of solid lipid ratio in curcumin loaded emulsions on its gastrointestinal fate: Colloidal stability and mucus absorption efficiency

Emulsions offer a promising approach for enhancing the bioavailability of lipophilic active compounds when administered orally. Nonetheless, the impact of lipid matrix composition on the efficacy of penetration and bioavailability remains uncertain. This research investigated the effects of solid lipid ratio in emulsions on colloidal stability, mucus permeability, and bioavailability in vivo. To assess colloidal stability in the gastrointestinal tract (GIT), Turbiscan was employed. The results indicated that an elevated solid lipid ratio improved intestinal stability through the formation of aggregations that resisted pancreatic absorption, as confirmed by TEM. The absorption in various intestinal sections was tested using the Ussing Chamber model. Notably, emulsion with 0 % solid lipid (G0M10) exhibited the highest cumulative permeation across the duodenum (221.2 ± 21.19 ng), jejunum (713.1 ± 20.93 ng), and ileum (1056.3 ± 392.06 ng) due to its higher in vitro release rate (>60 %) and smaller particle size. The cumulative permeation decreased with increasing solid lipid ratio. CLSM revealed that emulsions with a solid lipid ratio exceeding 50 % exhibited poor mucus permeability within 15 min due to aggregation during the passage in the GIT. However, over an extended penetration time (30 min), higher permeability was observed, reaching approximately 30 μm. In vitro release studies indicated that a higher solid lipid ratio resulted in a reduced release rate of curcumin (<60 %) compared to G0M10 (66.9 ± 3.58 %). Correlation analysis unveiled a positive link between bioavailability and in vitro release rate, while a negative correlation emerged with the solid lipid ratio. This work underscores the significance of solid lipid ratios in emulsions for optimizing bioavailability through their influence on stability, permeability, and release of lipophilic compounds in the GIT.

Liposomes encapsulation by pH driven improves the stability, bioaccessibility and bioavailability of urolithin A: A comparative study

Urolithin A (UroA) is gut metabolites of ellagitannins possessing a vast range of biological activities, but its poor water solubility and low bioavailability hinder its potential applications. This study utilized the pH dependent dissolution characteristics of UroA and employed a simple pH-driven method to load UroA into liposomes. The characterization and stability of obtained liposomes under different conditions were evaluated, and their oral bioavailability was tested by pharmacokinetics, and compared with UroA liposomes prepared using traditional thin film dispersion (TFM-ULs). Results indicated that liposomes could effectively encapsulate UroA. The UroA liposomes prepared by the pH-driven method (PDM-ULs) showed lower particle size, polydispersity index, zeta potential, and higher encapsulation efficiency than TFM-ULs. Interestingly, better thermal stability, storage stability, in vitro digestion stability, and higher bioaccessibility were also found on PDM-ULs. Moreover, pharmacokinetic experiments in rats demonstrated that PDM-ULs could significantly improve the bioavailability of UroA, with an absorption efficiency 1.91 times that of TFM-ULs. Therefore, our findings suggest that liposomes prepared by pH-driven methods have great potential in improving the stability and bioavailability of UroA.

Lipid-Based Nanotechnology: Liposome

Over the past several decades, liposomes have been extensively developed and used for various clinical applications such as in pharmaceutical, cosmetic, and dietetic fields, due to its versatility, biocompatibility, and biodegradability, as well as the ability to enhance the therapeutic index of free drugs. However, some challenges remain unsolved, including liposome premature leakage, manufacturing irreproducibility, and limited translation success. This article reviews various aspects of liposomes, including its advantages, major compositions, and common preparation techniques, and discusses present U.S. FDA-approved, clinical, and preclinical liposomal nanotherapeutics for treating and preventing a variety of human diseases. In addition, we summarize the significance of and challenges in liposome-enabled nanotherapeutic development and hope it provides the fundamental knowledge and concepts about liposomes and their applications and contributions in contemporary pharmaceutical advancement.

Encapsulation of resveratrol within size-controlled nanoliposomes: Impact on solubility, stability, cellular permeability, and oral bioavailability

This study examined the influence of the nanoliposomes (LPs) particle size on the solubility, antioxidant stability, in vitro release profile, Caco-2 cellular transport activity, cellular antioxidant activity, and in vivo oral bioavailability of resveratrol (RSV). LPs with sizes of 300, 150, and 75 nm were prepared using the thin-lipid film hydration method, followed by ultrasonication for 0, 2, and 10 min, respectively. Formulating small LPs (< 100 nm) was effective to enhance the solubility, in vitro release profile, cellular permeability, and cellular antioxidant activity of RSV. A similar pattern was observed for in vivo oral bioavailability. However, the size reduction of RSV-loaded LPs did not promote the antioxidant stability of RSV, owing to their large surface area used to interact with harsh environments. This study provides the better understanding of the appropriate particle size range of LPs to improve their in vitro and in vivo performances of RSV as an effective carrier for oral administration.

Preparation, characterization, and evaluation of flaxseed oil liposomes coated with chitosan and pea protein isolate hydrolysates

The effect of layer-by-layer coating of liposomes with chitosan and pea protein isolate hydrolysates (PPIH) was evaluated. Traditional flaxseed oil liposomes (FL Lipo) were used as a model for comparison to liposomes coated with chitosan and PPIH (FL LipoCP). The potential of PPIH as a coating material was evaluated. Additionally, the influence of chitosan and PPIH on vesicle size and zeta potential of liposomes was investigated. The chitosan layer of liposomes exhibited a loose structure. After the second layer of coating with PPIH, chitosan molecules were rearranged on the liposome surface, leading to a more compact and dense shell structure of liposomes. Electrostatic interactions, hydrogen bonds, and hydrophobic interactions favored the stability of FL LipoCP. Compared to FL Lipo, FL LipoCP displayed higher oxidation stability during storage and a slower release of flaxseed oil during in vitro digestion.

Development of an Oral Isoliquiritigenin Self-Nano-Emulsifying Drug Delivery System (ILQ-SNEDDS) for Effective Treatment of Eosinophilic Esophagitis Induced by Food Allergy

Isoliquiritigenin (ILQ) is a natural flavonoid with various pharmacological activities. In this study, we optimized the preparation method of self-nano-emulsion-loaded ILQ to further improve its bioavailability based on our previous study. In addition, its effect on the treatment of eosinophilic esophagitis was also evaluated. Combined surfactants and co-surfactants were screened, and the optimal formulation of ILQ-SNEDDS was determined according to droplet size, droplet dispersity index (DDI), and drug loading. The formulation was composed of ethyl oleate (oil phase), Tween 80 & Cremophor EL (surfactant, 7:3), and PEG 400 & 1,2-propylene glycol (cosurfactant, 1:1), with a mass ratio of 3:6:1. Its physicochemical properties, including drug loading, droplets' size, Zeta potential, appearance, and Fourier transform infrared (FTIR) spectroscopy, were characterized. In vitro release profile, in situ intestinal absorption, and in vivo pharmacokinetics were applied to confirm the improvement of oral ILQ bioavailability by NEDDS. Finally, the efficacy of ILQ-SNEDDS in the treatment of food allergy-induced eosinophilic esophagitis (EOE) was further evaluated. When the ILQ drug loading was 77.9 mg/g, ILQ-SNEDDS could self-assemble into sub-spherical uniform droplets with an average size of about 33.4 ± 2.46 nm (PDI about 0.10 ± 0.05) and a Zeta potential of approximately -10.05 ± 3.23 mV. In situ intestinal absorption showed that optimized SNEDDS significantly increased the apparent permeability coefficient of ILQ by 1.69 times, and the pharmacokinetic parameters also confirmed that SNEDDS sharply increased the max plasma concentration and bioavailability of ILQ by 3.47 and 2.02 times, respectively. ILQ-SNEDDS also significantly improved the apparent signs, allergic index, hypothermia and body weight of EoE model mice. ILQ-SNEDDS treatment significantly reduced the levels of inflammatory cytokines, such as TNF-α, IL-4, and IL-5, and the level of PPE-s-IgE in serum, and significantly inhibited the expression of TGF-β1 in esophageal tissue. SNEDDS significantly improved the solubility and bioavailability of ILQ. Additionally, ILQ-SNEDDS treatment attenuated symptomatology of EoE model mice, which was associated with inhibiting the production of T_H2 inflammatory cytokines and PPE-s-IgE and the expression of TGF-β1. The above results shows that ILQ-SNEDDS has great potential as a good candidate for the treatment of eosinophilic esophagitis.

Physical and Oxidative Water-in-Oil Emulsion Stability by the Addition of Liposomes from Shrimp Waste Oil with Antioxidant and Anti-Inflammatory Properties

Liposomes made of partially purified phospholipids (PL) from Argentine red shrimp waste oil were loaded with two antioxidant lipid co-extracts (hexane-soluble, Hx and acetone-soluble, Ac) to provide a higher content of omega-3 fatty acids. The physical properties of the liposomes were characterized by Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS) and Differential Scanning Calorimetry (DSC). The antioxidant and anti-inflammatory activity of the lipid extracts and liposomal suspensions were evaluated in terms of Superoxide and ABTS radical scavenging capacities and TNF-α inhibition. Uni-lamellar spherical liposomes (z-average ≈ 145 nm) with strong negative ζ potential (≈ -67 mV) were obtained in all cases. The high content of neutral lipids in the Hx extract caused structural changes in the bilayer membrane and decreased entrapment efficiency regarding astaxanthin and EPA + DHA contents. The liposomes loaded with the Hx/Ac extracts showed higher antioxidant and anti-inflammatory activity compared with empty liposomes. The liposomal dispersions improved the physical and oxidative stability of water-in-oil emulsions as compared with the PL extract, inducing pronounced close packing of water droplets. The liposomes decreased hydroperoxide formation in freshly made emulsions and prevented thio-barbituric acid-reactive substances (TBARS) accumulation during chilled storage. Liposomes from shrimp waste could be valuable nanocarriers and stabilizers in functional food emulsions.

Formulation and rheological evaluation of liposomes-loaded carbopol hydrogels based on thermal waters

The aims of this study were to develop topical liposomal hydrogels based on thermal waters (TWs) acquired in the region of Biskra (Northeast Algeria) and also to investigate their rheological properties. Liposomes containing two highly mineralized thermal waters, Baraka (BTW) and Salhine (STW), were prepared by probe sonication using phosphatidylcholine (PC) and cholesterol (Chol), plain or mixed with phosphatidylglycerol (PG). Based on their lipid composition, obtained liposomes presented vesicle sizes of 60 nm, a low polydispersity index, and various negative zeta potentials. It was noted that with increasing counterions charge in TWs the zeta potential of liposomes decreased toward neutral values.Carbopol (1%, w/w) hydrogels prepared with BTW, STW, and also demineralized water (placebo hydrogel) showed a non-Newtonian behavior, pseudoplastic fluid adjusted to Carreau model. The composition of thermal waters influenced highly the rheological properties of Carbopol hydrogels. Liposomal hydrogels were prepared by dispersing liposomes in hydrogels formulated with the same encapsulated thermal water. Regardless of composition or lipid concentration of added liposomes, the viscosity and viscoelastic parameters of Carbopol hydrogels changed negligibly. Indeed, liposome composition and lipid concentration seemed to have no effect on the rheological properties of Carbopol hydrogel in the presence of an important charge of cations. Hence, hydrogels and liposomal hydrogels based on thermal waters had suitable rheological properties for topical application and delivery of minerals in the skin.

A review of recent progress in improving the bioavailability of nutraceutical-loaded emulsions after oral intake

Increasing awareness of the health benefits of specific constituents in fruits, vegetables, cereals, and other whole foods has sparked a broader interest in the potential health benefits of nutraceuticals. Many nutraceuticals are hydrophobic substances, which means they must be encapsulated in colloidal delivery systems. Oil-in-water emulsions are one of the most widely used delivery systems for improving the bioavailability and bioactivity of these nutraceuticals. The composition and structure of emulsions can be designed to improve the water dispersibility, physicochemical stability, and bioavailability of the encapsulated nutraceuticals. The nature of the emulsion used influences the interfacial area and properties of the nutraceutical-loaded oil droplets in the gastrointestinal tract, which influences their digestion, as well as the bioaccessibility, metabolism, and absorption of the nutraceuticals. In this article, we review recent in vitro and in vivo studies on the utilization of emulsions to improve the bioavailability of nutraceuticals. The findings from this review should facilitate the design of more efficacious nutraceutical-loaded emulsions with increased bioactivity.

Effect of steam explosion pretreatment on the composition and bioactive characteristic of phenolic compounds in Chrysanthemum morifolium Ramat cv. Hangbaiju powder with various sieve fractions

Steam explosion (SE) pretreatment is an efficient technique to promote the fiber degradation and disrupt materials' cell wall. In this study, the effect of SE pretreatment on the changes in phenolic profile, and the in vitro digestion property of a Chinese indigenous herb "Hangbaiju" (HBJ) powder with various sieve fractions (150-, 180-, 250-, 425-, and 850-μm sieves) were studied. After SE pretreatment, the morphological structure, color attributes, and composition of phenolic compounds were altered significantly (p < .05). The composition and content of phenolic compounds were strongly correlated with particle sizes. The higher extraction yield of phenolic compounds was reached in the intermediate sieve fraction (ca. 250-μm sieves). During in vitro digestion, the changes in phenolic compounds were significant due to the transition from an acidic to the alkaline environment (p < .05). Based on the multivariate statistical analysis, apigenin-7-O-glucoside, luteolin-7-O-glucoside, and linarin, were viewed as the characteristic compounds among various samples. The results highlighted that the phytochemical properties mainly including the composition of phenolic compounds, and in vitro digestion properties of HBJ powder with intermediate sieve fraction could be improved after SE pretreatment.

The Potential Application of Pickering Multiple Emulsions in Food

Emulsions stabilized by adsorbed particles—Pickering particles (PPs) instead of surfactants and emulsifiers are called Pickering emulsions. Here, we review the possible uses of Pickering multiple emulsions (PMEs) in the food industry. Food-grade PMEs are very complex systems with high potential for application in food technology. They can be prepared by traditional two-step emulsification processes but also using complex techniques, e.g., microfluidic devices. Compared to those stabilized with an emulsifier, PMEs provide more benefits such as lower susceptibility to coalescence, possible encapsulation of functional compounds in PMEs or even PPs with controlled release, etc. Additionally, the PPs can be made from food-grade by-products. Naturally, w/o/w emulsions in the Pickering form can also provide benefits such as fat reduction by partial replacement of fat phase with internal water phase and encapsulation of sensitive compounds in the internal water phase. A possible advanced type of PMEs may be stabilized by Janus particles, which can change their physicochemical properties and control properties of the whole emulsion systems. These emulsions have big potential as biosensors. In this paper, recent advances in the application of PPs in food emulsions are highlighted with emphasis on the potential application in food-grade PMEs.

Alginate-Chitosan Coated Nanoliposomes as Effective Delivery Systems for Bamboo Leaf Flavonoids: Characterization, In Vitro Release, Skin Permeation and Anti-Senescence Activity

The use of bamboo leaf flavonoids (BLF) as functional food and cosmetic ingredients is limited by low bioavailability and difficulty in being absorbed by the intestine or skin. The aim of this study was to prepare BLF-loaded alginate-chitosan coated nanoliposomes (AL-CH-BLF-Lip) to overcome these challenges. The nanocarriers were characterized by dynamic light scattering, high performance liquid chromatography, Fourier transform infrared spectroscopy and differential scanning calorimetry. The biological activity was analyzed by in vitro antioxidant activity, transdermal absorption, cytotoxicity and AAPH induced HaCaT cell senescence model. The results showed that the size of nanocarriers ranged from 152.13 to 228.90 nm and had a low polydispersity index (0.25−0.36). Chitosan (CH) and alginate (AL) were successfully coated on BLF-loaded nanoliposomes (BLF-Lip), the encapsulation efficiency of BLF-Lip, BLF-loaded chitosan coated nanoliposomes (CH-BLF-Lip) and AL-CH-BLF-Lip were 71.31%, 78.77% and 82.74%, respectively. In addition, BLF-Lip, CH-BLF-Lip and AL-CH-BLF-Lip showed better in vitro release and free radical scavenging ability compared with naked BLF. In particular, the skin permeability of BLF-Lip, CH-BLF-Lip, and AL-CH-BLF-Lip increased 2.1, 2.4 and 2.9 times after 24 h, respectively. Furthermore, the use of nanoliposomes could significantly improve the anti-senescence activity of BLF (p < 0.01). Conclusively, alginate-chitosan coated nanoliposomes are promising delivery systems for BLF that can be used in functional foods and cosmetics.

Surface characteristics and emulsifying properties of whey protein/nanoliposome complexes

The surface characteristics and emulsifying properties of whey proteins (WP) after complexation with nanoliposomes (NL) were investigated. WP surface hydrophobicity enhanced after complexation with NL, and it indicated the exposure increase of WP hydrophobic groups. WPNL interfacial tension significantly decreased compared with that of WP. The interfacial protein content of WPNL-stabilized emulsions was slightly different from that of WP-stabilized emulsions. WP emulsifying properties were significantly improved after complexation with NL. The mean sizes and polydispersity indexes of WPNL-stabilized emulsion droplets were smaller than those of WP-stabilized emulsion droplets. The absolute zeta-potential values of WPNL-stabilized emulsions were greater than those of WP-stabilized emulsions. Electrostatic repulsion played a vital role in WPNL-stabilized emulsion stability. Moreover, surface and emulsifying properties of WPNL were changed by exterior factor-induced alteration of protein advanced structures. The emulsifying properties of WP after complexation with NL were improved due to the modification of WP surface characteristics.

Improved stability of liposome-stabilized emulsions as coencapsulation delivery system for vitamin B2, vitamin E and β-carotene

To realize the co-encapsulation of multiple nutraceuticals with different solubilities, Pickering emulsions stabilized by freshly-prepared liposome suspension stabilized emulsion (Fre-Lip-Sus-E) and hydrated lyophilized liposome stabilized emulsion (Hyd-Lyo-Lip-E) were prepared, in...

Application of Liposome Encapsulating Lactobacillus curvatus Extract in Cosmetic Emulsion Lotion

Probiotic extracts have various positive attributes, such as antioxidant, tyrosinase inhibitory, and antimicrobial activity. Lactobacillus curvatus produces bacteriocin, which activates the lipid membrane structure and has potential as a natural preservative for cosmetic emulsions. In this study, L. curvatus extract was encapsulated in liposomes and formulated as an oil-in-water (O/W) emulsion. Radical scavenging activity, tyrosinase inhibition, and challenge tests were conducted to confirm the liposome activity and the activity of the applied lotion emulsion. The liposome-encapsulated extract had a relatively high absolute ζ-potential (52.53 > 35.43), indicating its stability, and 96% permeability, which indicates its potential as an active agent in lotion emulsions. Characterization of emulsions containing the liposomes also indicated a stable state. The liposome-encapsulated extract exhibited a higher radical scavenging activity than samples without the extract and non-encapsulated samples, and the functionality was preserved in the lotion emulsion. The tyrosinase inhibition activity of the lotion emulsion with the liposome-encapsulated extract was similar to that of the non-treated extract. Candida albicans and Aspergillus niger were also inhibited in the challenge test with the lotion emulsions during storage. Collectively, these findings indicate that the liposome-encapsulated extract and the lotion containing the encapsulated extract have potential applicability as natural preservatives.

Novel Nanoliposome Codelivered DHA and Anthocyanidin: Characterization, In Vitro Infant Digestibility, and Improved Cell Uptake

There are still many challenges in understanding the absorption and transport mechanism of liposomes in the gastrointestinal tract of infants, especially for liposome-coentrapped two or more substances. In this study, novel docosahexaenoic acid (DHA)-anthocyanidin-codelivery liposomes (DA-LPs) were fabricated and characterized, and their digestive and absorptive behaviors were evaluated using the in vitro infant digestive method combined with the Caco-2 cell model. The liposomal bilayer structure remained intact with the particles aggregated in simulated infant gastric fluid, while their phospholipid membrane underwent enzymatic lipolysis under simulated intestinal conditions. Compared to single substance-loaded liposomes (DHA- or anthocyanidin-loaded liposomes), the digested DA-LPs showed better cell viability, higher cellular uptake and membrane fluidity, and lower reactive oxygen species (ROS). It can be concluded that DA-LPs are promising carriers for simultaneously transporting hydrophobic and hydrophilic molecules and may be beneficial for improving nutrient absorption and alleviating intestinal stress oxidation.

Physiological fluid interfaces: Functional microenvironments, drug delivery targets, and first line of defense

Fluid interfaces, i.e. the boundary layer of two liquids or a liquid and a gas, play a vital role in physiological processes as diverse as visual perception, oral health and taste, lipid metabolism, and pulmonary breathing. These fluid interfaces exhibit a complex composition, structure, and rheology tailored to their individual physiological functions. Advances in interfacial thin film techniques have facilitated the analysis of such complex interfaces under physiologically relevant conditions. This allowed new insights on the origin of their physiological functionality, how deviations may cause disease, and has revealed new therapy strategies. Furthermore, the interactions of physiological fluid interfaces with exogenous substances is crucial for understanding certain disorders and exploiting drug delivery routes to or across fluid interfaces. Here, we provide an overview on fluid interfaces with physiological relevance, namely tear films, interfacial aspects of saliva, lipid droplet digestion and storage in the cell, and the functioning of lung surfactant. We elucidate their structure-function relationship, discuss diseases associated with interfacial composition, and describe therapies and drug delivery approaches targeted at fluid interfaces. STATEMENT OF SIGNIFICANCE: Fluid interfaces are inherent to all living organisms and play a vital role in various physiological processes. Examples are the eye tear film, saliva, lipid digestion & storage in cells, and pulmonary breathing. These fluid interfaces exhibit complex interfacial compositions and structures to meet their specific physiological function. We provide an overview on physiological fluid interfaces with a focus on interfacial phenomena. We elucidate their structure-function relationship, discuss diseases associated with interfacial composition, and describe novel therapies and drug delivery approaches targeted at fluid interfaces. This sets the scene for ocular, oral, or pulmonary surface engineering and drug delivery approaches.

Nanoliposomes for encapsulation and calcium delivery of egg white peptide-calcium complex

Nanoliposomes and crude liposomes loaded with egg white peptide-calcium complex (EWP-Ca) were fabricated by thin-film dispersion with or without dynamic high-pressure microfluidization. Their physiochemical properties, in vitro stability, and calcium release profiles were investigated in this study. Results showed that the EWP-Ca-loaded nanoliposomes exhibited spherical structures with a lower particle size and polydispersity index as well as a higher thermal stability as compared to the corresponding crude liposomes. Further investigations revealed that EWP-Ca was embedded into the liposomes mainly through hydrogen bonding and present in an amorphous form within the liposomes. Additionally, the EWP-Ca-loaded nanoliposomes effectively slowed the release of calcium in gastric digestion, allowing more soluble calcium to enter the intestinal tract; in the subsequent intestinal digestion, the EWP-Ca-loaded nanoliposomes were more electrically and physically stable than the crude liposomes. Therefore, the EWP-Ca-loaded nanoliposomes could be used as a favorable dietary calcium delivery system to promote calcium bioavailability. PRACTICAL APPLICATION: Nanoliposomes were fabricated in this study to encapsulate the egg white peptide-calcium complex (EWP-Ca) for calcium delivery. The EWP-Ca-loaded nanoliposomes effectively slowed the release of calcium in gastric digestion, allowing more soluble calcium to enter the intestinal tract, and were more electrically and physically stable in the subsequent intestinal digestion. Therefore, the EWP-Ca-loaded nanoliposomes may be incorporated in calcium-fortified food to enhance calcium delivery for maintaining bone health.

The interaction mechanism between liposome and whey protein: Effect of liposomal vesicles concentration

The interaction mechanism between liposomes (Lips) and whey protein isolates (WPI) with different mass ratios was explored in this paper. After binding with different concentration of Lips, the changes in hydrophilic and hydrophobic regions of WPI were investigated with fluorescein isothiocyanate (FITC) and pyrene fluorescence probes. The spatial structure changes of WPI were further characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy, and circular dichroism. The results indicated that the structure of WPI was changed due to binding with Lips in hydrophilic and hydrophobic groups. The binding process might result in the migration, recombination, and alignment of WPI and Lip groups. Moreover, the oil-water interfacial tension with WPI decreased from 9.20 mN/m to 3.29 mN/m upon increasing the Lip-to-WPI ratio. This work suggests that the physiochemical properties of Lip-WPI complexes could be manipulated by adjusting the Lip-to-WPI ratio. This study shed some light on the mechanism explanation of the WPI structural changes due to the interaction with Lips during food processing.

Carboxymethyl chitosan-decorated proliposomes as carriers for improved stability and sustained release of flaxseed oil

A flaxseed oil carboxymethyl chitosan-decorated proliposome system was fabricated in this research. The physicochemical characteristics, stability, and in vitro release behaviors of flaxseed oil were studied and compared with that of flaxseed oil-loaded liposomes. The results of dynamic light scattering, transmission electron microscopy, and oxidation stability indicated that the storage stability of proliposomes was better. After 28 days of storage, the peroxide value of flaxseed oil-loaded liposomes (20.1 meq/kg) was significantly (P < 0.05) higher than that of flaxseed oil-loaded proliposomes (9.0 meq/kg); the thiobarbituric acid reactive substances in the former (0.53 mmol/kg) was also higher than that in the latter (0.27 mmol/kg). The in vitro release behavior of flaxseed oil indicated the proliposomes were more stable in the simulated gastrointestinal fluids. Therefore, the flaxseed oil-loaded proliposome system could be a promising vehicle for delivery flaxseed oil in food industry. PRACTICAL APPLICATION: A flaxseed oil-loaded proliposome delivery system was fabricated in this research. Their physical and oxidation stability of flaxseed oil were improved, and the in vitro cumulative release of flaxseed oil was delayed compared with flaxseed oil liposomes. This system may provide an effective strategy for the flaxseed oil encapsulation in the food industry.

Food-Grade Pickering Emulsions: Preparation, Stabilization and Applications

In recent years, Pickering emulsions have emerged as a new method and have attracted much attention in the fields of food sciences. Unlike conventional emulsions, Pickering emulsions are stabilized by solid particles, which can irreversibly adsorb on the oil-water interface to form a dense film to prevent the aggregation of droplets. The research and development of food-grade solid particles are increasingly favored by scientific researchers. Compared with conventional emulsions, Pickering emulsions have many advantages, such as fewer using amounts of emulsifiers, biocompatibility and higher safety, which may offer feasibility to have broad application prospects in a wide range of fields. In this article, we review the preparation methods, stabilization mechanism, degradation of Pickering emulsions. We also summarize its applications in food sciences in recent years and discuss its future prospects and challenges in this work.