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1.
Food Sci Technol Int ; 27(6): 485-498, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34487460

RESUMO

The optimal conditions for elaborating oil/water nanoemulsions of lemongrass (LG), cinnamon bark (CB) and cinnamon leaves (CL) essential oils and their antimicrobial activity against Zygosaccharomyces bailii at pH 4.00 were studied. The effect of the emulsification methodology on the physical stability and antimicrobial activity of the nanoemulsions were also evaluated. Furthermore, the sensory impact of nanoemulsions added to an apple juice was tested. LG and CL nanoemulsions were elaborated by ultrasonication and CB nanoemulsion, by high-speed homogenization. They were stable for at least 120 days at 25 °C. They exhibited antimicrobial activity against Z. bailii being CB the most effective since it showed the smallest MIC value (156.3 mg/l), followed by LG (468.8 mg/l) and CL (1250.0 mg/l). A slight increase in growth rate was observed due to ultrasonication. An additive interaction in relation to the inhibitory effect between LG and CB nanoemulsions against Z. bailii was observed. While nanoemulsions obtained would be used as natural antimicrobial agents in food and beverage products, only LG nanoemulsion at MIC concentration diluted was acceptable in juice showing the sensory impact of essential oils on foods.


Assuntos
Cymbopogon , Óleos Voláteis , Zygosaccharomyces , Cinnamomum zeylanicum , Emulsões , Óleos Voláteis/farmacologia , Saccharomycetales
2.
Langmuir ; 37(33): 10200-10213, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34379976

RESUMO

Self-emulsifying drug-delivery systems (SEDDS) have been extensively shown to increase oral absorption of solvation-limited compounds. However, there has been little clinical and commercial use of these formulations, in large part because the demonstrated advantages of SEDDS have been outweighed by our inability to precisely predict drug absorption from SEDDS using current in vitro assays. To overcome this limitation and increase the biological relevancy of in vitro assays, an absorption function can be incorporated using biomimetic membranes. However, the effects that SEDDS have on the integrity of a biomimetic membrane are not known. In this study, a quartz crystal microbalance with dissipation monitoring and total internal reflection fluorescence microscopy were employed as complementary methods to in vitro lipolysis-permeation assays to characterize the interaction of various actively digested SEDDS with a liquescent artificial membrane comprising lecithin in dodecane (LiDo). Observations from surface analysis showed that interactions between the digesting SEDDS and LiDo membrane coincided with inflection points in the digestion profiles. Importantly, no indications of membrane damage could be observed, which was supported by flux profiles of the lipophilic model drug felodipine (FEL) and impermeable marker Lucifer yellow on the basal side of the membrane. There was a correlation between the digestion kinetics of the SEDDS and the flux of FEL, but no clear correlation between solubilization and absorption profiles. Membrane interactions were dependent on the composition of lipids within each SEDDS, with the more digestible lipids leading to more pronounced interactions, but in all cases, the integrity of the membrane was maintained. These insights demonstrate that LiDo membranes are compatible with in vitro lipolysis assays for improving predictions of drug absorption from lipid-based formulations.


Assuntos
Biomimética , Sistemas de Liberação de Medicamentos , Administração Oral , Emulsões , Intestino Delgado , Lecitinas , Solubilidade
3.
Food Res Int ; 147: 110460, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399460

RESUMO

A novel concept of stabilizing multiple-phase food structure such as emulsion using solely the constitutional bacteria enables an all-natural food grade formulation and thus a clean label declaration. In this paper, we propose an efficient approach to hydrophobically modifying the surface of lactic acid bacteria Lactobacillus rhamnosus (LGG) using lauroyl ahloride (LC) in non-aqueous media. Compared to the unmodified bacteria, cell hydrophobicity was dramatically altered upon modification, according to the higher percentages of microbial adhesion to hexadecane (MATH) and water contact angles (WCA) of LC-modified bacteria. No evident changes were found in bacterial surface charge before and after LC modification. By using one-step homogenization, all the modified bacteria were able to generate stabile water-in-oil-in-water (W/O/W) double emulsions where bacteria were observed on oil-water interfaces of the primary and secondary droplets. Modification using high LC concentrations (10 and 20 w/w%) led to rapid autoaggregation of bacteria in aqueous solution. A long-term lethal effect of modification primarily came from lyophilization and no apparent impact was detected on the instantaneous culturability of modified bacteria.


Assuntos
Lactobacillales , Emulsões , Interações Hidrofóbicas e Hidrofílicas
4.
Food Res Int ; 147: 110554, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399531

RESUMO

Media milling, an efficient and organic solvent-free method without the use of chemical modification, has been developed to engineer novel walnut-based miscellaneous colloidal particles. The defatted walnut flour particles (DWFPs), which were prepared by a novel continuous phase transition extraction method operated under low temperature (i.e., 50-65 °C) followed by 6-h media milling, were spherical shape with an average size of 753.0 ± 27.8 nm. These particles were mainly composed of proteins (55.6 ± 0.2 wt%) and carbohydrates (24.0 ± 0.2 wt%) and demonstrated the ability to form a gel-like network structure in Pickering emulsions (PEs). The visual observation and confocal laser scanning microscopy (CLSM) showed that the PE droplets stabilized by DWFPs had a good stability over a prolonged storage time (i.e., 3-month storage). Increasing particle concentration (c) in aqueous phase led to the increased emulsified phase volume, decreased oil droplet sizes, and increased storage moduli G' for the viscoelastic responses. As the oil volume fraction (ϕ) increased, the emulsified phase volume fraction and droplet size increased while their rheological properties shifted from fluid-like to gel-like behaviors. The method developed in this study is significant in value-added utilization of walnut products and provides a new insight into facile fabrication of stable food-grade Pickering emulsions-based functional foods using miscellaneous particle stabilizers from walnut extracts.


Assuntos
Juglans , Emulsões , Farinha , Tamanho da Partícula , Reologia
5.
Food Res Int ; 147: 110558, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399535

RESUMO

Food behavior during oral processing plays an essential role in the perception of texture. It depends on different factors, including food structure and composition, as well as its behavior when interacting with saliva. This study aimed to investigate the effect of particle size and thickener type of emulsified systems on physical, rheological, tribological, and oral oily coating properties under oral conditions. Six matrices based on oil-in-water emulsions with different particle sizes (NE-nanoemulsion and CE-conventional emulsions) were prepared using a mixture of emulsifiers (10% w/w) and sunflower oil (10% w/w). Thickened agents were added to the matrices (NE and CE) at different concentrations (3-4.5% w/w of starch-ST or 0.4-0.8% w/w xanthan gum-XG) to obtain equi-viscous samples (NE-EV) with their CE-based counterpart. Results showed a decrease in apparent viscosity values under oral conditions (saliva and shearing at 10 s-1) during the shear time, but this behavior was more evident in starch-based matrices. The lubrication properties of the different matrices depended mainly on the thickener concentration since equi-viscous samples (NE-ST-EV and NE-XG-EV) showed higher coefficient of friction (CoF) values. Finally, oral oily coating was more related to the oil droplets size than to the type of thickener since all NE-based matrices showed a higher amount of coating retained compared to the CE-based ones. Therefore, NE-based matrices could be used as an alternative to increase mouthfeel sensations in food emulsions.


Assuntos
Emulsificantes , Emulsões , Tamanho da Partícula , Reologia , Viscosidade
6.
Food Res Int ; 147: 110573, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399546

RESUMO

In this study, stable water-in-oil emulsions stabilized solely by a naturally occurring steroidal sapogenin was reported for the first time. The results show that a concentrated emulsion with an internal water ratio of up to 60% can be obtained with only 3% of diosgenin concentration. The concentration of diosgenin had a significant effect on the microstructure and rheological properties of the emulsions. More importantly, the emulsion has excellent freeze/thaw stability and thermal stability. The results of polarized light microscopy, CLSM, and XRD indicate that the great structural properties and high stability of the emulsion can be attributed to the combined action of the diosgenin crystal shells on the droplet surface and needle-crystals in the continuous phase. That is, Pickering stabilization and network stabilization acting synergistically on stabilization of the emulsions. This novel food grade water-in-oil emulsions demonstrated great potential for application in food and biomedical-related fields.


Assuntos
Diosgenina , Nanopartículas , Sapogeninas , Emulsões , Água
7.
Talanta ; 234: 122586, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364415

RESUMO

This paper reports the development of a method based on the extraction induced by emulsion breaking (EIEB) for the determination of Cr, Cu and Mn in asphalt by high-resolution continuum source atomic absorption spectrometry. In optimized conditions, the extraction efficiency ranged from 88.6 for Cu to 104.5% for Mn. Measurements were carried out at the primary lines of the three analytes. The limits of detection were 0.02 µg g-1 for Cr, 0.01 µg g-1 for Cu and 7.11 ng g-1 for Mn. The precision, expressed as the relative standard deviation, ranged from 1.0 for Cu to 9.1% for Cr. The performance of the proposed method was compared to previously reported sample preparation procedures, including microwave-assisted acid digestion (MW-AD), ultrasound-assisted acid extraction (USE), emulsification (E), and direct dilution in organic solvent (DD). The parameters evaluated were matrix effects, limits of detection and quantification, characteristic mass, precision, accuracy, sample stability and applicability for routine analysis. The methods most suitable for Cu determination were EIEB, MW-AD, USE and E. For Cr and Mn, the best results were obtained by EIEB, MW-AD and DD procedures.


Assuntos
Hidrocarbonetos , Emulsões , Espectrofotometria Atômica
8.
Molecules ; 26(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34361651

RESUMO

Here we introduce a new method aiming the immobilization of bioactive principles onto polymeric substrates, combining a surface activation and emulsion entrapment approach. Natural products with antimicrobial/antioxidant properties (essential oil from Syzygium aromaticum-clove and vegetal oil from Argania spinosa L-argan) were stabilized in emulsions with chitosan, a natural biodegradable polymer that has antimicrobial activity. The emulsions were laid on poly(lactic acid) (PLA), a synthetic biodegradable plastic from renewable resources, which was previously activated by plasma treatment. Bioactive materials were obtained, with low permeability for oxygen, high radical scavenging activity and strong inhibition of growth for Listeria monocytogenes, Salmonella Typhimurium and Escherichia coli bacteria. Clove oil was better dispersed in a more stable emulsion (no separation after six months) compared with argan oil. This leads to a compact and finely structured coating, with better overall properties. While both clove and argan oils are highly hydrophobic, the coatings showed increased hydrophilicity, especially for argan, due to preferential interactions with different functional groups in chitosan. The PLA films coated with oil-loaded chitosan showed promising results in retarding the food spoilage of meat, and especially cheese. Argan, and in particular, clove oil offered good UV protection, suitable for sterilization purposes. Therefore, using the emulsion stabilization of bioactive principles and immobilization onto plasma activated polymeric surfaces we obtained a bioactive material that combines the physical properties and the biodegradability of PLA with the antibacterial activity of chitosan and the antioxidant function of vegetal oils. This prevents microbial growth and food oxidation and could open new perspectives in the field of food packaging materials.


Assuntos
Quitosana , Óleo de Cravo , Emulsões , Microbiologia de Alimentos/métodos , Embalagem de Alimentos/métodos , Inocuidade dos Alimentos/métodos , Óleos Vegetais , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Quitosana/farmacologia , Óleo de Cravo/química , Óleo de Cravo/farmacologia , Emulsões/química , Emulsões/farmacologia , Óleos Vegetais/química , Óleos Vegetais/farmacologia
9.
Molecules ; 26(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34443336

RESUMO

We develop a suitable delivery system for niaouli essential oil (NEO) using a nanoemulsification method for acne vulgaris. Prepared nanoemulsions (NEs) were characterized for droplet dimension, rheology, surface charge, and stability. The ability of NEO formulations against Propionibacterium acnes and Staphylococcus epidermidis was investigated and all formulations showed antiacne potential in vitro. Ex vivo permeation studies indicated significant improvement in drug permeations and steady state flux of all NEO-NEs compared to the neat NEO (p < 0.05). On the basis of the studied pharmaceutical parameters, enhanced ex vivo skin permeation, and marked effect on acne pathogens, formulation NEO-NE4 was found to be the best (oil (NEO; 10% v/v); Kolliphor EL (9.25% v/v), Carbitol (27.75% v/v), and water (53% v/v)). Concisely, the in vitro and ex vivo results revealed that nanoemulsification improved the delivery as well as bioactivities of NEO significantly.


Assuntos
Portadores de Fármacos/química , Melaleuca/química , Nanoestruturas/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Emulsões , Óleos Voláteis/metabolismo , Permeabilidade , Pele/metabolismo , Staphylococcus epidermidis/efeitos dos fármacos
10.
Int J Mol Sci ; 22(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34360758

RESUMO

The current study describes the experimental design guided development of PEGylated nanoemulsions as parenteral delivery systems for curcumin, a powerful antioxidant, as well as the evaluation of their physicochemical characteristics and antioxidant activity during the two years of storage. Experimental design setup helped development of nanoemulsion templates with critical quality attributes in line with parenteral application route. Curcumin-loaded nanoemulsions showed mean droplet size about 105 nm, polydispersity index <0.15, zeta potential of -40 mV, and acceptable osmolality of about 550 mOsm/kg. After two years of storage at room temperature, all formulations remained stable. Moreover, antioxidant activity remained intact, as demonstrated by DPPH (IC50 values 0.078-0.075 mg/mL after two years) and FRAPS assays. In vitro release testing proved that PEGylated phospholipids slowed down the curcumin release from nanoemulsions. The nanoemulsion carrier has been proven safe by the MTT test conducted with MRC-5 cell line, and effective on LS cell line. Results from the pharmacokinetic pilot study implied the PEGylated nanoemulsions improved plasma residence of curcumin 20 min after intravenous administration, compared to the non-PEGylated nanoemulsion (two-fold higher) or curcumin solution (three-fold higher). Overall, conclusion suggests that developed PEGylated nanoemulsions present an acceptable delivery system for parenteral administration of curcumin, being effective in preserving its stability and antioxidant capacity at the level highly comparable to the initial findings.


Assuntos
Antioxidantes , Curcumina , Portadores de Fármacos , Nanoestruturas , Animais , Antioxidantes/química , Antioxidantes/farmacocinética , Antioxidantes/farmacologia , Disponibilidade Biológica , Linhagem Celular Tumoral , Curcumina/química , Curcumina/farmacocinética , Curcumina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Emulsões , Humanos , Masculino , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Projetos Piloto , Ratos , Ratos Sprague-Dawley
11.
Int J Mol Sci ; 22(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361049

RESUMO

Nanotechnology in the field of drug delivery comes with great benefits due to the unique physicochemical properties of newly developed nanocarriers. However, they may come as well with severe toxicological side effects because of unwanted accumulation in organs outside of their targeted site of actions. Several studies showed an unintended accumulation of various nanocarriers in female sex organs, especially in the ovaries. Some led to inflammation, fibrosis, or decreasing follicle numbers. However, none of these studies investigated ovarian accumulation in context to both reproductive aging and particle size. Besides the influences of particle size, the biodistribution profile may be altered as well by reproductive aging because of reduced capacities of the reticuloendothelial system (RES), changes in sex steroid hormone levels as well as altering ovarian stromal blood flow. This systematic investigation of the biodistribution of intravenously (i.v) injected nanoemulsions revealed significant dependencies on the two parameters particle size and age starting from juvenile prepubescent to senescent mice. Using fluorescent in vivo and ex vivo imaging, prepubescent mice showed nearly no accumulation of nanoemulsion in their uteri and ovaries, but high accumulations in the organs of the RES liver and spleen independently of the particle size. In fertile adult mice, the accumulation increased significantly in the ovaries with an increased particle size of the nanoemulsions by nearly doubling the portion of the average radiant efficiency (PARE) to ~10% of the total measured signal of all excised organs. With reproductive aging and hence loss of fertility in senescent mice, the accumulation decreased again to moderate levels, again independently of the particle size. In conclusion, the ovarian accumulation of these nanocarriers depended on both the age plus the particle size during maturity.


Assuntos
Envelhecimento/metabolismo , Nanopartículas/metabolismo , Ovário/metabolismo , Células 3T3 , Animais , Emulsões/administração & dosagem , Emulsões/farmacocinética , Emulsões/toxicidade , Feminino , Concentração Inibidora 50 , Injeções Intravenosas , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Camundongos , Nanopartículas/administração & dosagem , Nanopartículas/toxicidade , Ovário/crescimento & desenvolvimento , Baço/crescimento & desenvolvimento , Baço/metabolismo , Distribuição Tecidual
12.
Exp Parasitol ; 228: 108142, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34375652

RESUMO

We investigated the in vitro activity and selectivity, and in vivo efficacy of ravuconazole (RAV) in self-nanoemulsifying delivery system (SNEDDS) against Trypanosoma cruzi. Novel formulations of this poorly soluble C14-α-demethylase inhibitor may improve its efficacy in the experimental treatment. In vitro activity was determined in infected cardiomyocytes and efficacy in vivo evaluated in terms of parasitological cure induced in Y and Colombian strains of T. cruzi-infected mice. In vitro RAV-SNEDDS exhibited significantly higher potency of 1.9-fold at the IC50 level and 2-fold at IC90 level than free-RAV. No difference in activity with Colombian strain was observed in vitro. Oral treatment with a daily dose of 20 mg/kg for 30 days resulted in 70% of cure for RAV-SNEDDS versus 40% for free-RAV and 50% for 100 mg/kg benznidazole in acute infection (T. cruzi Y strain). Long-term treatment efficacy (40 days) was able to cure 100% of Y strain-infected animals with both RAV preparations. Longer treatment time was also efficient to increase the cure rate with benznidazole (Y and Colombian strains). RAV-SNEDDS shows greater efficacy in a shorter time treatment regimen, it is safe and could be a promising formulation to be evaluated in other pre-clinical models to treat T. cruzi and fungi infections.


Assuntos
Doença de Chagas/tratamento farmacológico , Tiazóis/administração & dosagem , Triazóis/administração & dosagem , Trypanosoma cruzi/efeitos dos fármacos , Animais , Doença de Chagas/parasitologia , Emulsões , Feminino , Células Hep G2 , Humanos , Concentração Inibidora 50 , Camundongos , Miócitos Cardíacos , Nanoestruturas , Ratos , Tiazóis/farmacologia , Tiazóis/uso terapêutico , Tiazóis/toxicidade , Triazóis/farmacologia , Triazóis/uso terapêutico , Triazóis/toxicidade
13.
Chemistry ; 27(52): 13161-13171, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34383383

RESUMO

Hydrogels with mechanical elasticity and conductivity are ideal materials in wearable devices. However, traditional hydrogels are fragile upon mechanical loading and lose functions in climate change because the internal water undergoes freeze and dehydration. Herein, we synthesize stable emulsions at high and low temperatures by introducing glycerol into the W/W emulsions. Then the high-stable emulsions are used as templates to produce the freestanding emulsion gels with enhanced mechanical strength and conductivity. The introduction of glycerol endows emulsions and emulsion gels with high and low temperature resistance (-20 to 90 °C). The fabricated strain sensors based on emulsion gels show high sensitivity (gauge factor=6.240), high stretchability (1081 %), fatigue resistance, self-healing and adhesion properties, realizing the repeatable and accurate detection of various human motions. These high-performance and eco-friendly emulsion gels can be promising candidates for next-generation artificial skin and human-machine interface.


Assuntos
Hidrogéis , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Emulsões , Géis , Humanos , Temperatura
14.
Soft Matter ; 17(35): 8086-8094, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34387296

RESUMO

A Good's buffer ionic liquid (GB-IL) composed of quaternary ammonium cations and Good's buffer anions is first introduced into a microemulsion system as a self-buffering and biocompatible electrolyte. The effects of the constituting ions of a GB-IL and their concentrations on the phase behavior of the anionic surfactant SDBS stabilized n-octane-H2O microemulsion system were studied for the first time using the ε-ß fish-like phase diagram method. The result indicates that the phase behavior of the above microemulsion system is greatly affected by GB-IL cations with a longer alkyl chain on the cation being more favorable for phase inversion. Compared with NaCl, a GB-IL of the same concentration is more efficient for achieving phase inversion, due to the dual role of an electrolyte and a co-alcohol. In addition to the phase behavior, the stability of horseradish peroxidase (HRP) solubilized in an SDBS stabilized bicontinuous microemulsion is also affected by a GB-IL. It is found that the variation of the cationic alkyl chain has a negligible effect on the microemulsion microstructure, but has a significant influence on the stability of the solubilized HRP. At a fixed concentration of the GB-IL, the quaternary ammonium cation with a longer alkyl chain is better for the stabilization of the HRP activity. For a given GB-IL, a higher level of the GB-IL results in a better HRP stability. More importantly, the GB-IL-buffered microemulsion, at the same level of the buffering salt, is more advantageous than the phosphate-buffered one for the stabilization of the HRP activity. This advantage is more pronounced for higher concentrations of the GB-IL. This difference in the HRP stability, caused by the buffering salts, should be ascribed to the microemulsion microstructure effect as well as the Hofmeister effect. The present study provides a guideline for the construction of a bicontinuous microemulsion with a simplified composition and stabilizing effect on the solubilized enzyme.


Assuntos
Líquidos Iônicos , Animais , Cátions , Emulsões , Peroxidase do Rábano Silvestre , Octanos , Tensoativos , Água
15.
Nutrients ; 13(8)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34444713

RESUMO

Herein, we investigate whether: (1) the administration of glucose or a lipid emulsion is useful in liver transplantation (LT) using steatotic (induced genetically or nutritionally) or non-steatotic livers from donors after brain death (DBDs); and (2) any such benefits are due to reductions in intestinal damage and consequently to gut microbiota preservation. In recipients from DBDs, we show increased hepatic damage and failure in the maintenance of ATP, glycogen, phospholipid and growth factor (HGF, IGF1 and VEGFA) levels, compared to recipients from non-DBDs. In recipients of non-steatotic grafts from DBDs, the administration of glucose or lipids did not protect against hepatic damage. This was associated with unchanged ATP, glycogen, phospholipid and growth factor levels. However, the administration of lipids in steatotic grafts from DBDs protected against damage and ATP and glycogen drop and increased phospholipid levels. This was associated with increases in growth factors. In all recipients from DBDs, intestinal inflammation and damage (evaluated by LPS, vascular permeability, mucosal damage, TLR4, TNF, IL1, IL-10, MPO, MDA and edema formation) was not shown. In such cases, potential changes in gut microbiota would not be relevant since neither inflammation nor damage was evidenced in the intestine following LT in any of the groups evaluated. In conclusion, lipid treatment is the preferable nutritional support to protect against hepatic damage in steatotic LT from DBDs; the benefits were independent of alterations in the recipient intestine.


Assuntos
Morte Encefálica , Fígado Gorduroso , Glucose/administração & dosagem , Transplante de Fígado , Fígado/metabolismo , Fosfolipídeos/administração & dosagem , Óleo de Soja/administração & dosagem , Trifosfato de Adenosina/metabolismo , Animais , Modelos Animais de Doenças , Emulsões/administração & dosagem , Fígado Gorduroso/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Intestinos/patologia , Intestinos/fisiopatologia , Fígado/patologia , Glicogênio Hepático/metabolismo , Masculino , Obesidade , Fosfolipídeos/metabolismo , Ratos , Ratos Zucker , Doadores de Tecidos
16.
Langmuir ; 37(32): 9802-9808, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34342454

RESUMO

High-internal phase emulsions (HIPEs) were considered as an important functional material and have been the focus of intense development effort, but their fundamental attributes have hardly been altered at either the microcosmic or macroscopic level, which severely limits their practical applications in various areas. In this work, we report a general strategy for creating complex HIPEs that can form interfacial films at liquid interfaces. Double HIPEs and Janus HIPEs are both realized for the first time. They feature complex microscopic patterns with short-range anisotropy and exhibit non-Newtonian pseudoplastic flow behavior. By taking advantage of their response to a high-pH subphase, interfacial films can be successfully obtained, which are tunable in thickness and morphologies under compression. Complex HIPEs can greatly expand the applications of liquid materials, and the interfacial films of droplets represent an important step toward producing 2D soft materials with a unique functionality that can be broadly applied to biological processes.


Assuntos
Emulsões
17.
Zhongguo Zhong Yao Za Zhi ; 46(14): 3583-3591, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34402281

RESUMO

This study explores the emulsifying material basis of Angelicae Sinensis Radix volatile oil (ASRVO) based on partial least squares (PLS) method and hydrophile-lipophile balance (HLB) value.The turbidity of ASRVO emulsion samples from Gansu,Yunnan,and Qinghai was determined and the chemical components in the emulsion were analyzed by GC-MS.The PLS model was established with the chemical components as the independent variable and the turbidity as the dependent variable and evaluated with indexes R~2X and R~2Y.The chemical components which were in positive correlation with the turbidity were selected and the HLB values were calculated to determine the emulsification material basis of ASRVO.The PLS models for the 81 emulsion samples had high R~2X and R~2Y values,which showed good fitting ability.Seven chemical components,2-methoxy-4-vinylphenol,trans-ligustilide,3-butylidene-1(3H)-isobenzofuranone,dodecane,1-methyl-4-(1-methylethylidene)-cyclohexene,trans-beta-ocimene,and decane,had positive correlation with turbidity.Particularly,the HLB value of 2-methoxy-4-vinylphenol was 4.4,which was the HLB range of surfactants to be emulsifiers and 2-methoxy-4-vinylphenol was positively correlated with turbidity of the ASRVO emulsion samples from the main producing area.Therefore,2-methoxy-4-vinylphenol was the emulsifying material basis of ASRVO.The selected emulsifying substances can lay a foundation for exploring the emulsification mechanism and demulsification solution of ASRVO.


Assuntos
Óleos Voláteis , China , Emulsões , Análise dos Mínimos Quadrados , Tensoativos
18.
Sensors (Basel) ; 21(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34372323

RESUMO

This work shows the application of an ultrasonic multiple-scattering sensor for monitoring water-in-petroleum emulsions. The sensor consists of a commercial ultrasonic transducer with an array of cylindrical scatterers placed in the near field. The scatterers are thin metal bars arranged in rows in front of the transducer. The backscattering signals were analyzed by calculating the wave energy and by a cross-correlation between signal segments; they were also used to determine the propagation velocity in the emulsions. The tests performed used emulsions with water volume concentrations from 0% to 50%. The results showed that both the signal energy and propagation velocity strongly depended on the concentration of water in the emulsion. Therefore, the ultrasonic multiple-scattering sensor can be used for on-line and real-time monitoring of the water content in water-in-crude-oil emulsions.


Assuntos
Petróleo , Emulsões , Petróleo/análise , Ultrassom , Água
19.
Anal Chem ; 93(27): 9390-9396, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34212731

RESUMO

The cationic content of water represents a major quality control parameter that needs to be followed by a rapid, on-site, and low-cost method. Herein, we report a novel method for a facile monitoring of the mineral content of drinking water by making use of responsive complex emulsions. The morphology of biphasic oil-in-water droplets solely depends on the balance of interfacial tensions, and we demonstrate that changes in the surfactant effectiveness, caused by variations in the mineral content inside the continuous phase, can be visualized by monitoring internal droplet shapes. An addition of metal cations can significantly influence the surfactant critical micelle concentrations and the surface excess values and therefore induce changes in the effectiveness of ionic surfactants, such as sodium dodecyl sulfate. The morphological response of Janus emulsions droplets was tracked via a simple microscopic setup. We observed that the extent of the droplet response was dependent on the salt concentration and valency, with divalent cations (responsive for water hardness), resulting in a more pronounced response. In this way, Ca2+ and Mg2+ levels could be quantitatively measured, which we showcased by determination of the mineral content of commercial water samples. The herein demonstrated device concept may provide a new alternative rapid monitoring of water hardness levels in a simple and cost-effective setup.


Assuntos
Tensoativos , Água , Emulsões , Dureza , Dodecilsulfato de Sódio
20.
AAPS PharmSciTech ; 22(5): 199, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34212274

RESUMO

An emulsion is a biphasic dosage form comprising of dispersed phase containing droplets that are uniformly distributed into a surrounding liquid which forms the continuous phase. An emulsifier is added at the interface of two immiscible liquids to stabilize the thermodynamically unstable emulsion. Various types of emulsions such as water-in-oil (w-o), oil-in-water (o-w), microemulsions, and multiple emulsions are used for delivering certain drugs in the body. Water (aqueous) phase is commonly used for encapsulating proteins and several other drugs in water-in-oil-in-water (w-o-w) emulsion technique. But this method has posed certain problems such as decreased stability, burst release, and low entrapment efficiency. Thus, a novel "solid-in-oil-in-water" (s-o-w) emulsion system was developed for formulating certain drugs, probiotics, proteins, antibodies, and tannins to overcome these issues. In this method, the active ingredient is encapsulated as a solid and added to an oil phase, which formed a solid-oil dispersion. This dispersion was then mixed with water to form a continuous phase for enhancing the drug absorption. This article focuses on the various studies done to investigate the effectiveness of formulations prepared as solid-oil-water emulsions in comparison to conventional water-oil-water emulsions. A summary of the results obtained in each study is presented in this article. The s-o-w emulsion technique may become beneficial in near future as it has shown to improve the stability and efficacy of the entrapped active ingredient.


Assuntos
Portadores de Fármacos/química , Emulsões/química , Óleos/química , Água/química , Diclofenaco/química , Diclofenaco/metabolismo , Estabilidade de Medicamentos , Microesferas , Nanoestruturas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Proteínas/química , Proteínas/metabolismo
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