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Sample records for acid emulsion system

  1. [Linoleic acid and the immune system. Controversies about lipid emulsions].

    PubMed

    García de Lorenzo, A; Culebras, J M

    1992-01-01

    The selection of a given lipidic function for nutritional backup requires not only knowledge of the metabolism of the different existing lipidic emulsions and of their specific therapeutic indications, but also of their contraindications and controversies because, apart from their calorific value, the contribution of liposoluble vitamins and their function in preventing essential fatty acid deficiencies, we know that they are powerful metabolic modulators. This in associated with the fact that manipulation of dietary lipids (enteral or parenteral) can affect and modulate the response to the disease, attack or infection by improving or impairing the different immune functions. This review is focused on the scientific publications which have examined the varying effects of lipidic emulsions, in quantity and in quality (particularly linoleic acid) on the immune system, on the fatty acid composition of the cellular membranes and on the production of and prostaglandins and leukotrienes. An update is given of the known interrelation between lipids and immunity, with appraisal of triglycerides and long-medium -- and short-chain fatty acids, mixtures of medium -- and long-chain triglycerides, the proportions between infinity-3/infinity-6, and structured lipids.

  2. Development of stable flaxseed oil emulsions as a potential delivery system of ω-3 fatty acids.

    PubMed

    Goyal, Ankit; Sharma, Vivek; Upadhyay, Neelam; Singh, A K; Arora, Sumit; Lal, Darshan; Sabikhi, Latha

    2015-07-01

    The objective of the present study was to develop a stable flaxseed oil emulsion for the delivery of omega-3 (ω-3) fatty acids through food fortification. Oil-in-water emulsions containing 12.5 % flaxseed oil, 10 % lactose and whey protein concentrate (WPC)-80 ranging from 5 to 12.5 % were prepared at 1,500, 3,000 and 4,500 psi homogenization pressure. Flaxseed oil emulsions were studied for its physical stability, oxidative stability (peroxide value), particle size distribution, zeta (ζ)-potential and rheological properties. Emulsions homogenized at 1,500 and 4,500 psi pressure showed oil separation and curdling of WPC, respectively, during preparation or storage. All the combinations of emulsions (homogenized at 3,000 psi) were physically stable for 28 days at 4-7 ºC temperature and did not show separation of phases. Emulsion with 7.5 % WPC showed the narrowest particle size distribution (190 to 615 nm) and maximum zeta (ζ)-potential (-33.5 mV). There was a slight increase in peroxide value (~20.98 %) of all the emulsions (except 5 % WPC emulsion), as compared to that of free flaxseed oil (~44.26 %) after 4 weeks of storage. Emulsions showed flow behavior index (n) in the range of 0.206 to 0.591, indicating higher shear thinning behavior, which is a characteristic of food emulsions. Results indicated that the most stable emulsion of flaxseed oil (12.5 %) can be formulated with 7.5 % WPC-80 and 10 % lactose (filler), homogenized at 3,000 psi pressure. The formulated emulsion can be used as potential omega-3 (ω-3) fatty acids delivery system in developing functional foods such as pastry, ice-creams, curd, milk, yogurt, cakes, etc.

  3. Highly unsaturated fatty acid might act as an antioxidant in emulsion system oxidized by azo compound.

    PubMed

    Gotoh, Naohiro; Noguchi, Yosuke; Ishihara, Akiko; Yamaguchi, Kaita; Mizobe, Hoyo; Nagai, Toshiharu; Otake, Ikuko; Ichioka, Kenji; Wada, Shun

    2010-01-01

    Now it is recognized that DHA is oxidatively stable fatty acid compared with linoleic acid (LA) in emulsified system, although DHA is oxidatively unstable in a bulk system. In fact, an emulsified mixture of DHA and LA behaves as in a bulk system, namely the oxidative stability of DHA becomes lower than that of LA. Therefore, in this study, tridocosahexaenoate (DDD) and glycerol trilinoleate (LLL) were separately emulsified using TritonX-100 as an emulsifier and DDD emulsion was mixed with the oxidizing LLL emulsion using a water-soluble radical initiator, 2,2'-azobis(2-aminopropane) dihydrochloride. As a result, DHA suppressed the oxidation of LA, while DHA was not significantly oxidized. This suppression ability was examined using glycerol trieicosapentaenoate, glycerol trilinolenate, or glycerol trioleate instead of DDD and it was found that this activity was increased with the increasing number of double bonds in the structure. Furthermore, the same type of experiment was carried out using a lipid-soluble radical initiator, 2,2'-azobisisobutyronitrile and the similar result was obtained. These results indicated that a highly polyunsaturated fatty acid might act as an antioxidant in an emulsion system oxidized by an azo compound.

  4. Comparison of simple, double and gelled double emulsions as hydroxytyrosol and n-3 fatty acid delivery systems.

    PubMed

    Flaiz, Linda; Freire, María; Cofrades, Susana; Mateos, Raquel; Weiss, Jochen; Jiménez-Colmenero, Francisco; Bou, Ricard

    2016-12-15

    The purpose of this study was to compare three different emulsion-based systems, namely simple emulsion, double emulsion and gelled double emulsion, for delivery of n-3 fatty acids (perilla oil at 300g/kg) and hydroxytyrosol (300mg/kg). Considering that their structural differences may affect their physical and oxidative stability, this was studied by storing them at 4°C for 22days in the dark. The results showed that the oxidative status was maintained in all systems by the addition of hydroxytyrosol. However, there was some loss of hydroxytyrosol, mainly during sample storage and during preparation of the gelled double emulsion. Moreover, the antioxidant loss was more pronounced in more compartmentalized systems, which was attributed to their increased surface area. However, the double emulsion was found to be less stable than the gelled emulsion. Overall, the encapsulation of labile compounds in more complex systems needs to be carefully studied and adapted to specific technological and/or nutritional requirements.

  5. Development of a Supported Emulsion Liquid Membrane System for Propionic Acid Separation in a Microgravity Environment

    NASA Technical Reports Server (NTRS)

    Li, Jin; Hu, Shih-Yao B.; Wiencek, John M.

    2001-01-01

    Perstractive fermentation is a good way to increase the productivity of bioreactors. Using Propionibacteria as the model system, the feasibility of using supported emulsion liquid membrane (SELM) for perstractive fermentation is assessed in this study. Five industrial solvents were considered as the solvent for preparing the SELM. The more polar a solvent is, the higher the partition coefficient. However, toxicity of a solvent also increases with its polarity. CO-1055 (industrial decanol/octanol blend) has the highest partition coefficient toward propionic acid among the solvents that has no molecular toxicity toward Propionibacteria. A preliminary extraction study was conducted using tetradecane as solvent in a hydrophobic hollow fiber contactor. The result confirmed that SELM eliminates the equilibrium limitation of conventional liquid-liquid extraction, and allows the use of a non-toxic solvent with low partition coefficient.

  6. Phase behavior and formation of o/w nano-emulsion in vegetable oil/ mixture of polyglycerol polyricinoleate and polyglycerin fatty acid ester/water systems.

    PubMed

    Wakisaka, Satoshi; Nakanishi, Masami; Gohtani, Shoichi

    2014-01-01

    It is reported that mixing polyglycerol polyricinoleate (PGPR) and polyglycerol laurilester has a great emulsifying capacity, and consequently fine oil-in-water (o/w) emulsions can be formed. However, the role of PGPR is not clear. The objective of this research is to investigate the phase behavior of vegetable oil/mixture of PGPR and polyglycerol fatty acid ester/water systems, and to clarify the role of PGPR in making a fine emulsion. Phase diagrams were constructed to elucidate the optimal process for preparing fine emulsions. In all the systems examined in this study, the phases, including the liquid crystal phase (L(c)) and sponge phase (L(3)), spread widely in the phase diagrams. We examined droplet size of the emulsions prepared from each phase and found that o/w nano-emulsions with droplet sizes as small as 50 nm were formed by emulsifying either from a single L(3) phase or a two-phase region, L(c) + L(3). These results indicate that a sponge phase L(3) or liquid crystal phase L(c) or both is necessary to form an o/w nano-emulsion whose average droplet diameter is less than 50 nm for PGPR and polyglycerin fatty acid ester mixtures used as surfactant.

  7. Engineering of acidic O/W emulsions with pectin.

    PubMed

    Alba, K; Sagis, L M C; Kontogiorgos, V

    2016-09-01

    Pectins with distinct molecular design were isolated by aqueous extraction at pH 2.0 or 6.0 and were examined in terms of their formation and stabilisation capacity of model n-alkane-in-water emulsions at acidic pH (pH 2.0). The properties and stability of the resulting emulsions were examined by means of droplet size distribution analysis, Lifshitz-Slyozov-Wagner modelling, bulk rheology, interfacial composition analysis, large-amplitude oscillatory surface dilatational rheology, electrokinetic analysis and fluorescence microscopy. Both pectin preparations were able to emulsify alkanes in water but exhibited distinct ageing characteristics. Emulsions prepared using pectin isolated at pH 6.0 were remarkably stable with respect to droplet growth after thirty days of ageing, while those prepared with pectin isolated at pH 2.0 destabilised rapidly. Examination of chemical composition of interfacial layers indicated multi-layered adsorption of pectins at the oil-water interface. The higher long-term stability of emulsions prepared with pectin isolated at high pH is attributed to mechanically stronger interfaces, the highly branched nature and the low hydrodynamic volume of the chains that result in effective steric stabilisation whereas acetyl and methyl contents do not contribute to the long-term stability. The present work shows that it is possible by tailoring the fine structure of pectin to engineer emulsions that operate in acidic environments.

  8. Lipid Emulsion for Local Anesthetic Systemic Toxicity

    PubMed Central

    Ciechanowicz, Sarah; Patil, Vinod

    2012-01-01

    The accidental overdose of local anesthetics may prove fatal. The commonly used amide local anesthetics have varying adverse effects on the myocardium, and beyond a certain dose all are capable of causing death. Local anesthetics are the most frequently used drugs amongst anesthetists and although uncommon, local anaesthetic systemic toxicity accounts for a high proportion of mortality, with local anaesthetic-induced cardiac arrest particularly resistant to standard resuscitation methods. Over the last decade, there has been convincing evidence of intravenous lipid emulsions as a rescue in local anesthetic-cardiotoxicity, and anesthetic organisations, over the globe have developed guidelines on the use of this drug. Despite this, awareness amongst practitioners appears to be lacking. All who use local anesthetics in their practice should have an appreciation of patients at high risk of toxicity, early symptoms and signs of toxicity, preventative measures when using local anesthetics, and the initial management of systemic toxicity with intravenous lipid emulsion. In this paper we intend to discuss the pharmacology and pathophysiology of local anesthetics and toxicity, and the rationale for lipid emulsion therapy. PMID:21969824

  9. Emulsion Mapping in Pork Meat Emulsion Systems with Various Lipid Types and Brown Rice Fiber

    PubMed Central

    Choi, Yun-Sang; Kim, Young-Boong; Park, Jinhee

    2015-01-01

    This study was conducted to evaluate emulsion mapping between emulsion stability and cooking yields, apparent viscosity, and hardness of reduced-fat pork emulsion systems. The reduced-fat emulsion systems were supplemented with different lipid types and brown rice bran fiber (BRF) concentrations. Compared to the control with 30% back fat, lower emulsion stability and higher cooking yield of meat emulsion systems were observed in T1 (30% back fat+1% BRF), T2 (30% back fat+2% BRF), T3 (30% back fat+3% BRF), T4 (30% back fat+6% BRF), and T15 (10% back fat+10% canola oil+2% BRF). Lower emulsion stability and higher apparent viscosity were observed in T1, T2, T3, T4, and T8 (20% back fat+3% BRF) compared to the control. Lower emulsion stability and higher hardness was detected in all treatments compared with the control, except T5 (20% back fat), T10 (10% back fat+10% canola oil+2% BRF), T11 (10% back fat+10% olive oil+2% BRF), T12 (10% back fat+10% grape seed oil+2% BRF), and T13 (10% back fat+10% soybean oil+2% BRF). This approach has been found particularly useful for highlighting differences among the emulsified properties in emulsion meat products. Thus, the results obtained with emulsion mapping are useful in making emulsified meat products of desired quality characteristics, partially replacing pork back fat with a mix of 10% back fat, 10% canola oil and 2% BRF was most similar to the control with 30% pork back fat. PMID:26761836

  10. Physical and chemical stability of gum arabic-stabilized conjugated linoleic acid oil-in-water emulsions.

    PubMed

    Yao, Xiaolin; Xu, Qiong; Tian, Dazhi; Wang, Nana; Fang, Yapeng; Deng, Zhongyang; Phillips, Glyn O; Lu, Jiang

    2013-05-15

    Oil-in-water (O/W) emulsions have been used as a delivery system to protect conjugated linoleic acid (CLA), a polyunsaturated fatty acid, from oxidation. Conventional gum arabic (GA) and two matured gum arabic samples (EM2 and EM10) were used as emulsifiers to prepare CLA-in-water emulsions. The emulsions have optimal physical and chemical stability at gum concentrations of 5% for all three gums. Emulsions with higher gum concentrations are more susceptible to lipid oxidation. This is attributed to reduced physical stability at higher gum concentrations because of the coalescence and depletion-induced flocculation of the emulsion droplets. The prooxidants iron and copper intrinsically contained in the gums could also contribute to this instability. Among the three gums, EM10 provides the most effective protection for CLA both physically and chemically, because of its superior interfacial properties over GA and EM2.

  11. Field testing of asphalt-emulsion radon-barrier system

    SciTech Connect

    Hartley, J.N.; Freeman, H.D.; Baker, E.G.; Elmore, M.R.; Nelson, D.A.; Voss, C.F.; Koehmstedt, P.L.

    1981-09-01

    Three years of laboratory and field testing have demonstrated that asphalt emulsion seals are effective radon diffusion barriers. Both laboratory and field tests in 1979, 1980 and 1981 have shown that an asphalt emulsion seal can reduce radon fluxes by greater than 99.9%. The effective diffusion coefficient for the various asphalt emulsion admix seals averages about 10/sup -6/ cm/sup 2//s. The 1981 joint field test is a culmination of all the technology developed to date for asphalt emulsion radon barrier systems. Preliminary results of this field test and the results of the 1980 field test are presented. 18 figures, 6 tables.

  12. Emulsion based cast booster - a priming system

    SciTech Connect

    Gupta, R.N.; Mishra, A.K.

    2005-07-01

    This paper explores the potential of emulsion based cast booster to be used as primer to initiate bulk delivered emulsion explosives used in mines. An attempt has been made for comparative study between conventional cast booster and emulsion based cast booster in terms of the initiation process developed and their capability to develop and maintain the stable detonation process in the column explosives. The study has been conducted using a continuous velocity of detonation (VOD) measuring instrument. During this study three blasts have been monitored. In each blast two holes have been selected for study, the first hole being initiated with conventional cast booster while the other one with emulsion based cast booster. The findings of the study advocates that emulsion based cast booster is capable of efficient priming of bulk delivered column explosive with stable detonation process in the column. Further, the booster had advantages over the conventional PETN/TNT based cast booster. 5 refs., 2 figs., 1 tab., 1 photo.

  13. Stable emulsions prepared by self-assembly of hyaluronic acid and chitosan for papain loading.

    PubMed

    Zhao, Donghua; Wei, Wei; Zhu, Ye; Sun, Jianhua; Hu, Qiong; Liu, Xiaoya

    2015-04-01

    A simple, green and effective process is developed to fabricate hyaluronic acid (HA)/chitosan (CS) complex colloidal particles through electrostatic interactions. The obtained complexes can be used as biocompatible emulsifiers and novel potential carriers for papain loading. An HA/CS mass ratio of 2 is the optimal condition leading to the smallest Dh (420.9 nm). The complexes with eight different mass ratios are used to stabilize white oil/water emulsions. The structure of the complexes at the oil-water interface varies in response to the mass ratio and can be classified into two typical structures, similar to typical polymeric surfactants and solid particulate emulsifiers. Furthermore, papain is introduced into the complex systems. Formation of the papain/HA/CS complexes in a compact form can protect the enzyme. Here, a novel strategy is introduced to fabricate a biocompatible emulsion from the HA/CS complexes and demonstrate that the stable complex is a suitable enzyme delivery system.

  14. Optimization of folic acid nano-emulsification and encapsulation by maltodextrin-whey protein double emulsions.

    PubMed

    Assadpour, Elham; Maghsoudlou, Yahya; Jafari, Seid-Mahdi; Ghorbani, Mohammad; Aalami, Mehran

    2016-05-01

    Due to susceptibility of folic acid like many other vitamins to environmental and processing conditions, it is necessary to protect it by highly efficient methods such as micro/nano-encapsulation. Our aim was to prepare and optimize real water in oil nano-emulsions containing folic acid by a low energy (spontaneous) emulsification technique so that the final product could be encapsulated within maltodextrin-whey protein double emulsions. A non ionic surfactant (Span 80) was used for making nano-emulsions at three dispersed phase/surfactant ratios of 0.2, 0.6, and 1.0. Folic acid content was 1.0, 2.0, and 3.0mg/mL of dispersed phase by a volume fraction of 5.0, 8.5, and 12%. The final optimum nano-emulsion formulation with 12% dispersed phase, a water to surfactant ratio of 0.9 and folic acid content of 3mg/mL in dispersed phase was encapsulated within maltodextrin-whey protein double emulsions. It was found that the emulsification time for preparing nano-emulsions was between 4 to 16 h based on formulation variables. Droplet size decreased at higher surfactant contents and final nano-emulsions had a droplet size<100 nm. Shear viscosity was higher for those formulations containing more surfactant. Our results revealed that spontaneous method could be used successfully for preparing stable W/O nano-emulsions containing folic acid.

  15. Bilayers at High pH in the Fatty Acid Soap Systems and the Applications for the Formation of Foams and Emulsions.

    PubMed

    Xu, Wenlong; Zhang, Heng; Zhong, Yingping; Jiang, Liwen; Xu, Mengxin; Zhu, Xionglu; Hao, Jingcheng

    2015-08-20

    In our previous work, we reported bilayers at high pH in the stearic acid/CsOH/H2O system, which was against the traditional viewpoint that fatty acid (FA) bilayers must be formed at the pKa of the fatty acid. Herein, the microstructures at high pH of several fatty acid soap systems were investigated systematically. We found that palmitic acid/KOH/H2O, palmitic acid/CsOH/H2O, stearic acid/KOH/H2O, and stearic acid/CsOH/H2O systems can form bilayers at high pH. The bilayer structure was demonstrated by cryogenic transmission electron microscopy (cryo-TEM) and deuterium nuclear magnetic resonance ((2)H NMR), and molecular dynamics simulation was used to confirm the formation of bilayers. The influence of fatty acids with different chain lengths (n = 10, 12, 14, 16, and 18) and different counterions including Li(+), Na(+), K(+), Cs(+), (CH3)4N(+), (C2H5)4N(+), (C3H7)4N(+), and (C4H9)4N(+) on the formation of bilayers was discussed. The stability of foam and emulsification properties were compared between bilayers and micelles, drawing the conclusion that bilayer structures possess a much stronger ability to foam and stronger emulsification properties than micelles do.

  16. Investigation of different emulsion systems for dermal delivery of nicotinamide.

    PubMed

    Tuncay, Sakine; Özer, Özgen

    2013-01-01

    Nicotinamide (NA) has been shown to have beneficial effects on several skin diseases such as tumor, acne vulgaris, photodamage, cellulite and atopic dermatitis. The purpose of this study was to develop a multiple emulsion and a microemulsion formulation as delivery systems for NA. A two-step process was used to prepare the W/O/W multiple emulsion. Optimum microemulsion formulation was selected by using construction of pseudo-ternary phase diagram. The physicochemical properties such as droplet size and viscosity measurements, stability studies were also evaluated. Ex-vivo permeation studies were performed with Franz-type diffusion cells and the samples were analysed by high performance liquid chromatography (HPLC). The permeation data showed that there was no significant difference between multiple emulsion and microemulsion (p > 0.05). Transepidermal water loss (TEWL) was also measured. As a result of TEWL studies, a slight increase of TEWL values was observed for microemulsion formulation on rat skin when compared with multiple emulsion and commercial formulation. The results suggested that microemulsion and multiple emulsion formulations could be new and alternative dosage forms for topical application of NA.

  17. Study of O/W micro- and nano-emulsions based on propylene glycol diester as a vehicle for geranic acid.

    PubMed

    Jaworska, Małgorzata; Sikora, Elżbieta; Ogonowski, Jan; Konieczna, Monika

    2015-01-01

    Nano- and microemulsions containing as the oil phase caprylic/capric propylene glycol diesters (Crodamol PC) were investigated as potential vehicle for controlled release of geranic acid. The influence of emulsifiers and co-surfactants on stability of the emulsions was investigated. Different kind of polysorbates (ethoxylated esters of sorbitan and fatty acids) were applied as the emulsifiers. The short-chain alcohols (ethanol, 1-propanol, 1-butanol) were used as co-surfactants. The emulsions were prepared at ambient temperature (25°C), by the phase inversion composition method (PIC). The stable O/W high dispersed emulsion systems based on Crodamol PC, of mean droplets size less than 200 nm, were prepared. Microemulsions stabilized by the mixture of Polisorbat 80 and 1-butanol were characterized by the largest degree of dispersion (137 nm) and the lowest PDI value (0.094), at surfactant/co-surfactant: oil weight ratio 90:10. The stable nano-emulsion (mean droplet size of 33 nm) was obtained for surfactant: oil (S:O) weight ratio 90:10, without co-surfactant addition. This nano-emulsion was chosen to release studies. The obtained results showed that the prepared stable nano-emulsion can be used as a carrier for controlled release of geranic acid. The active substance release from the nano-emulsion and the oil solution, after 24 hours was 22%.

  18. Removal of acetic acid from simulated hemicellulosic hydrolysates by emulsion liquid membrane with organophosphorus extractants.

    PubMed

    Lee, Sang Cheol

    2015-09-01

    Selective removal of acetic acid from simulated hemicellulosic hydrolysates containing xylose and sulfuric acid was attempted in a batch emulsion liquid membrane (ELM) system with organophosphorus extractants. Various experimental variables were used to develop a more energy-efficient ELM process. Total operation time of an ELM run with a very small quantity of trioctylphosphine oxide as the extractant was reduced to about a third of those required to attain almost the same extraction efficiency as obtained in previous ELM works without any extractant. Under specific conditions, acetic acid was selectively separated with a high degree of extraction and insignificant loss of xylose, and its purity and enrichment ratio in the stripping phase were higher than 92% and 6, respectively. Also, reused organic membrane solutions exhibited the extraction efficiency as high as fresh organic solutions did. These results showed that the current ELM process would be quite practical.

  19. Emulsion forming drug delivery system for lipophilic drugs.

    PubMed

    Wadhwa, Jyoti; Nair, Anroop; Kumria, Rachna

    2012-01-01

    In the recent years, there is a growing interest in the lipid-based formulations for delivery of lipophilic drugs. Due to their potential as therapeutic agents, preferably these lipid soluble drugs are incorporated into inert lipid carriers such as oils, surfactant dispersions, emulsions, liposomes etc. Among them, emulsion forming drug delivery systems appear to be a unique and industrially feasible approach to overcome the problem of low oral bioavailability associated with the BCS class II drugs. Self-emulsifying formulations are ideally isotropic mixtures of oils, surfactants and co-solvents that emulsify to form fine oil in water emulsions when introduced in aqueous media. Fine oil droplets would pass rapidly from stomach and promote wide distribution of drug throughout the GI tract, thereby overcome the slow dissolution step typically observed with solid dosage forms. Recent advances in drug carrier technologies have promulgated the development of novel drug carriers such as control release self-emulsifying pellets, microspheres, tablets, capsules etc. that have boosted the use of "self-emulsification" in drug delivery. This article reviews the different types of formulations and excipients used in emulsion forming drug delivery system to enhance the bioavailability of lipophilic drugs.

  20. Pro-oxidant/antioxidant behaviours of ascorbic acid, tocopherol, and plant extracts in n-3 highly unsaturated fatty acid rich oil-in-water emulsions.

    PubMed

    Jayasinghe, Chamila; Gotoh, Naohiro; Wada, Shun

    2013-12-01

    This study investigated the oxidative stability of n-3 highly unsaturated fatty acid (n-3 HUFA) rich (35% n-3 HUFA) oil-in-water emulsions (10 wt% oil) with commercial antioxidants and natural plant extracts. Ascorbic acid, α-tocopherol, and the extracts of Indian gooseberry fruit (Emblica officinalis) (IGFE) and sweet basil leaves (Ocimum basilicum L.) (SBLE) were used for the study as antioxidants. The progress of oxidation in the systems was evaluated at 35 °C over 120 h against a control (without antioxidant) by monitoring the formation of primary (conjugated dienes) and secondary (volatile carbonyl compounds) oxidation products. Volatile carbonyl compounds were trapped as derivatives of pentafluorophenyl hydrazine and quantified by headspace solid-phase microextraction analysis. About 40 volatile carbonyls were successfully identified by this method. trans,trans-2,4-Heptadienal, trans,cis-2,4-heptadienal, 3,5-octadien-2-one, and 1-penten-3-ol were predominant. The volatile carbonyl compounds and conjugated dienes were formed at low rates in emulsion systems in which α-tocopherol and natural plant extracts had been introduced, compared to the control. Emulsion systems containing ascorbic acid showed low stability, as indicated by the oxidation products that were formed at high rates compared to the control. These results indicated that ascorbic acid activated the oxidation reactions in n-3 HUFA rich water emulsions, while natural plant extracts that were rich in polyphenols and α-tocopherol were active as antioxidants. The present study further demonstrated the applicability of the polar paradox theory in the determination of stability for n-3 HUFA rich water emulsions with commercial antioxidants and natural plant extracts.

  1. Enhanced enteral bioavailability of vancomycin using water-in-oil-in-water multiple emulsion incorporating highly purified unsaturated fatty acid.

    PubMed

    Kajita, M; Morishita, M; Takayama, K; Chiba, Y; Tokiwa, S; Nagai, T

    2000-10-01

    The aim of this study was to evaluate the potential of an emulsion incorporating unsaturated fatty acids to improve the mucosal absorption of poorly absorbed drugs from rat intestinal loops in situ, using a water-in-oil-in-water (W/O/W) multiple emulsion. Vancomycin hydrochloride (VCM) was used as a model drug with low oral bioavailability. The entrapment efficiency of VCM in the emulsion was approximately 60% and remained constant over storage for 1 month at 4 degrees C. The emulsion incorporating C18 unsaturated fatty acids or docosahexaenoic acid (DHA) markedly enhanced VCM absorption after colonic and rectal dosing. The effectiveness of DHA on VCM colonic absorption improvement was the same as that of oleic acid, and less than that of linoleic and linolenic acids. For rectal dosing, bioavailability was similar among various emulsions, in the range 40-50%. The effect of the emulsion incorporating oleic acid or DHA on improving VCM enteral bioavailability was not increased proportional to the incorporated amount. The electrical resistance of membranes was not changed by the incorporation of various fatty acids in emulsions. Our results indicated that W/O/W emulsions incorporating C18 unsaturated fatty acid or DHA were useful carriers for improving the absorption of poorly absorbable drugs via the intestinal tract without gross changes to tight junction function.

  2. Characteristics of meat emulsion systems as influenced by different levels of lemon albedo.

    PubMed

    Sarıçoban, C; Ozalp, B; Yılmaz, M T; Ozen, G; Karakaya, M; Akbulut, M

    2008-11-01

    The effect of the addition of lemon albedo on the functional properties of emulsions was studied by using a model system. Oil/water (O/W) model emulsion systems were prepared by the addition of two types of lemon albedo (raw and dehydrated) at five concentrations (0.0%, 2.5%, 5.0%, 7.5% and 10%) to mechanically deboned chicken meat. The emulsion capacity, stability, viscosity and flow properties of the prepared model emulsions were analyzed. In addition, the colour parameters of cooked emulsion gel were determined. The addition of lemon albedo increased the emulsion capacity (EC) and the highest EC value was reached with 5% of albedo added. However, further increase in the albedo concentration caused an inverse trend in the EC values. A similar trend was observed in the emulsion stability (ES) values. Dehydrated albedo (DA) addition caused higher EC and ES values than did raw albedo (RA). DA increased the L(∗), a(∗) and b(∗) values of the cooked emulsion gels. Emulsion viscosity (EV) values were positively correlated with an increase in albedo concentration and the highest EV value was obtained from the emulsions with 10% albedo. Albedo addition did not change the flow properties of the emulsions and, in addition, increased the pseudoplasticity. As a consequence, the use of lemon albedo might be a potential dietary fiber source to enhance the functional and technological properties for frankfurter-type meat products.

  3. Ammonium salts of polymaleic acids and use as corrosion inhibitors in water-in-oil emulsions

    SciTech Connect

    Oppenlaender, K.; Barthold, K.; Stork, K.

    1984-03-13

    The subject invention relates to salts of polymaleic acids having a molecular weight between 200 and 1500 and to their use in preventing the corrosion of metal caused by hydrogen sulfide and carbon dioxide in water-in-oil emulsions such as crude oil.

  4. Biocompatible water-in-oil emulsion as a model to study ascorbic acid effect on lipid oxidation.

    PubMed

    Mosca, Monica; Ceglie, Andrea; Ambrosone, Luigi

    2008-04-17

    A biocompatible water-in-oil (W/O) emulsion has been used as a model to study the effect of ascorbic acid (AA) on the oxidation of the oil (glycerol trioleate, GTO) continuous phase. The model system consisted of 3 wt % water dispersed in GTO containing 0.5 wt % sodium oleate (NaO)/oleic acid (OA) mixture (NaO/OA = 20/80 mol/mol %) as a stabilizer. To study the ascorbic acid effect on GTO light-promoted oxidation, we added aqueous solutions of ascorbic acid to GTO in place of distilled water. Results obtained as peroxide values show that ascorbic acid activity depends on its concentration and it is affected by the characteristics of the W/O interface. In the presence of ascorbyl palmitate (AP) or sorbitan trioleate (Span 85) in the continuous phase, ascorbic acid activity increases in the first few hours of oxidation. The effect of ascorbic acid has been related to emulsion structure by calculating characteristic parameters of the droplet size distributions by means of optical microscopy.

  5. Synthesis of some glucose-fatty acid esters by lipase from Candida antarctica and their emulsion functions.

    PubMed

    Ren, Kangzi; Lamsal, Buddhi P

    2017-01-01

    The synthesis of glucose esters with palmitic acid, lauric acid and hexanoic acid using lipase enzyme was studied and their emulsion functionality in oil-in-water system were compared. Reactions at 3:1M ratio of fatty acids-to-glucose had the highest conversion percentages (over 90% for each of the fatty acid). Initial conversion rate increased as substrate solubility increased. Ester bond formation was confirmed by nuclear magnetic resonance technique that the chemical shifts of glucose H-6 and α-carbon protons of fatty acids in the ester molecules shifted to the higher fields. Contact angle of water on esters' pelleted surface increased as the hydrophobicity increased. Glucose esters' and commercial sucrose esters' functionality as emulsifiers were compared. Glucose esters delayed, but did not prevent coalescence, because the oil droplets diameter doubled during 7days. Sucrose esters prevented coalescence during 7days since the droplets diameter did not have significant change.

  6. Physicochemical properties of β-carotene emulsions stabilized by chlorogenic acid-lactoferrin-glucose/polydextrose conjugates.

    PubMed

    Liu, Fuguo; Wang, Di; Xu, Honggao; Sun, Cuixia; Gao, Yanxiang

    2016-04-01

    In this study, the influence of chlorogenic acid (CA)-lactoferrin (LF)-glucose (Glc) conjugate and CA-LF-polydextrose (PD) conjugate on the physicochemical characteristics of β-carotene emulsions was investigated. Novel emulsifiers were formed during Maillard reaction between CA-LF conjugate and Glc/PD. The physicochemical properties of β-carotene emulsions were characterized by droplet size, ζ-potential, rheological behavior, transmission changes during centrifugal sedimentation and β-carotene degradation. Results showed that the covalent attachment of Glc or PD to CA-LF conjugate effectively increased the hydrophilicity of the oil droplets surfaces and strengthened the steric repulsion between the oil droplets. Glucose was better than polydextrose for the conjugation with CA-LF conjugate to stabilize β-carotene emulsions. In comparison with LF and CA-LF-Glc/PD mixtures, CA-LF-Glc/PD ternary conjugates exhibited better emulsifying properties and improved physical stability of β-carotene emulsions during the freeze-thaw treatment. In addition, CA-LF-Glc/PD conjugates significantly enhanced chemical stability of β-carotene in the emulsions against ultraviolet light exposure.

  7. Chemistry of natural fuel: Use of wastes of synthetic fatty acid production for obtaining water-bitumen emulsions

    SciTech Connect

    Syroezhko, A.M.; Antipova, E.I.; Paukku, A.N.

    1995-12-10

    The possibility of producing water-emulsion waterproofing mastic and waterproofing coating based on bitumen, rubber crumb, and bottoms from production of synthetic fatty acids was studied. The physicochemical properties (softening point, ductility, sorptive properties, and friability) of the waterproofing coating based on a water-emulsion mastic were measured.

  8. Effects of Partial Beef Fat Replacement with Gelled Emulsion on Functional and Quality Properties of Model System Meat Emulsions

    PubMed Central

    2016-01-01

    The objective of this study was to investigate the effects of partial beef fat replacement (0, 30, 50, 100%) with gelled emulsion (GE) prepared with olive oil on functional and quality properties of model system meat emulsion (MSME). GE consisted of inulin and gelatin as gelling agent and characteristics of gelled and model system meat emulsions were investigated. GE showed good initial stability against centrifugation forces and thermal stability at different temperatures. GE addition decreased the pH with respect to increase in GE concentration. Addition of GE increased lightness and yellowness but reduced redness compared to control samples. The results of the study showed that partial replacement of beef fat with GE could be used for improving cooking yield without negative effects on water holding capacity and emulsion stability compared to C samples when replacement level is up to 50%. The presence of GE significantly affected textural behaviors of samples (p<0.05). In conclusion, our study showed that GE have promising impacts on developing healthier meat product formulations besides improving technological characteristics. PMID:28115885

  9. A computer system to analyze showers in nuclear emulsions: Center Director's discretionary fund report

    NASA Technical Reports Server (NTRS)

    Meegan, C. A.; Fountain, W. F.; Berry, F. A., Jr.

    1987-01-01

    A system to rapidly digitize data from showers in nuclear emulsions is described. A TV camera views the emulsions though a microscope. The TV output is superimposed on the monitor of a minicomputer. The operator uses the computer's graphics capability to mark the positions of particle tracks. The coordinates of each track are stored on a disk. The computer then predicts the coordinates of each track through successive layers of emulsion. The operator, guided by the predictions, thus tracks and stores the development of the shower. The system provides a significant improvement over purely manual methods of recording shower development in nuclear emulsion stacks.

  10. Na-caseinate/oil/water systems: emulsion morphology diagrams.

    PubMed

    Tan, Hui Lin; McGrath, Kathryn M

    2012-09-01

    The concentrated (dispersed phase 50-70 wt%) composition space of Na-caseinate, a family of milk proteins, stabilised emulsions was investigated for three different oils: soybean oil, palm olein and tetradecane with pH 6.8 phosphate buffer continuous phase. The variation of emulsion stability and microstructure were explored using static light scattering, diffusion nuclear magnetic resonance, cryo-scanning electron microscopy, rheology and the time varying macroscopic phase separation of the emulsions. For soybean oil and palm olein a rich diversity of emulsion microstructures and stabilities are realised. Five emulsion domains, each having a different microstructure and macroscopic stability have been identified within the composition space probed. For the lowest concentrations of emulsifier bridging flocculation is evident and emulsions are of low stability. Increasing Na-caseinate concentration leads to an increased stability and the existence of distinct individual oil droplets, visualised using cryo-scanning electron microscopy. Further increases in Na-caseinate concentration reduce emulsion stability due to depletion flocculation. Na-caseinate self-assembly is then initiated. At sufficiently high Na-caseinate and/or oil concentrations the continuous phase of the emulsion is a three-dimensional protein network and emulsion stability is again enhanced. At the limits of the emulsion composition space a gel-like paste is formed. The diversity of emulsion microstructure is reduced when tetradecane is the discrete phase. Na-caseinate self-assembly is limited and there is no evidence for formation of a protein network.

  11. Preparation of finely dispersed O/W emulsion from fatty acid solubilized in subcritical water.

    PubMed

    Khuwijitjaru, Pramote; Kimura, Yukitaka; Matsuno, Ryuichi; Adachi, Shuji

    2004-10-01

    A novel method for preparing a finely dispersed oil-in-water emulsion is proposed. Octanoic acid dissolved in water at a high temperature of 220 or 230 degrees C at 15 MPa was combined with an aqueous solution of a surfactant and then the mixture was cooled. When a nonionic surfactant, decaglycerol monolaurate (ML-750) or polyoxyethylene sorbitan monolaurate (Tween 20), was used, fine emulsions with a median oil droplet diameter of 100 nm or less were successfully prepared at ML-750 and Tween 20 concentrations of 0.083% (w/v) and 0.042%, respectively, or higher. The diameters were much smaller than those of oil droplets prepared by the conventional homogenization method using a rotor/stator homogenizer. However, an anionic surfactant, sodium dodecyl sulfate, was not adequate for the preparation of such fine emulsions by the proposed method. Although the interfacial tensions between octanoic acid and the surfactant solutions were measured at different temperatures, they were not an indication for selecting a surfactant for the successful preparation of the fine emulsion by the proposed method.

  12. Changes in Antioxidant Defense System Using Different Lipid Emulsions in Parenteral Nutrition in Children after Hematopoietic Stem Cell Transplantation

    PubMed Central

    Baena-Gómez, María Auxiliadora; De La Torre Aguilar, María José; Mesa, María Dolores; Pérez Navero, Juan Luis; Gil-Campos, Mercedes

    2015-01-01

    Background: Traditionally, lipids used in parenteral nutrition (PN) are based on ω-6 fatty acid-rich vegetable oils, such as soybean oil, with potential adverse effects involving oxidative stress. Methods: We evaluated the antioxidant defense system in children, after hematopoietic stem cell transplantation (HSCT), who were randomized to use a lipid emulsion with fish oil or soybean oil. Blood samples at baseline, at 10 days, and at the end of the PN were taken to analyze plasma retinol, α-tocopherol, β-carotene, coenzyme Q9 and coenzyme Q10 levels, and catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPOX), and superoxide dismutase (SOD) levels in lysed erythrocytes. Results: An increase in plasma α-tocopherol levels in the group of patients receiving the fish oil-containing emulsion (FO) compared with the group receiving the soybean emulsion was observed at day 10 of PN. Concurrently, plasma α-tocopherol increased in the FO group and β-carotene decreased in both groups at day 10 compared with baseline levels, being more significant in the group receiving the FO emulsion. Conclusion: FO-containing emulsions in PN could improve the antioxidant profile by increasing levels of α-tocopherol in children after HSCT who are at higher risk of suffering oxidative stress and metabolic disorders. PMID:26343717

  13. Lymphatic absorption of α-linolenic acid in rats fed flaxseed oil-based emulsion.

    PubMed

    Couëdelo, Leslie; Boué-Vaysse, Carole; Fonseca, Laurence; Montesinos, Emeline; Djoukitch, Sandrine; Combe, Nicole; Cansell, Maud

    2011-04-01

    The bioavailability of α-linolenic acid (ALA) from flaxseed oil in an emulsified form v. a non-emulsified form was investigated by using two complementary approaches: the first one dealt with the characterisation of the flaxseed oil emulsion in in vitro gastrointestinal-like conditions; the second one compared the intestinal absorption of ALA in rats fed the two forms of the oil. The in vitro study on emulsified flaxseed oil showed that decreasing the pH from 7·3 to 1·5 at the physiological temperature (37°C) induced instantaneous oil globule coalescence. Some phase separation was observed under acidic conditions that vanished after further neutralisation. The lecithin used to stabilise the emulsions inhibited TAG hydrolysis by pancreatic lipase. In contrast, lipid solubilisation by bile salts (after lipase and phospholipase hydrolysis) was favoured by preliminary oil emulsification. The in vivo absorption of ALA in thoracic lymph duct-cannulated rats fed flaxseed oil, emulsified or non-emulsified, was quantified. Oil emulsification significantly favoured the rate and extent of ALA recovery as measured by the maximum ALA concentration in the lymph (Cmax = 14 mg/ml at 3 h in the emulsion group v. 9 mg/ml at 5 h in the oil group; P < 0·05). Likewise, the area under the curve of the kinetics was significantly higher in the emulsion group (48 mg × h/ml for rats fed emulsion v. 26 mg × h/ml for rats fed oil; P < 0·05). On the whole, ALA bioavailability was improved with flaxseed oil ingested in an emulsified state. Data obtained from the in vitro studies helped to partly interpret the physiological results.

  14. Modeling of facilitated transport of phenylalanine by emulsion liquid membranes with di(2-ethylhexyl)phosphoric acid as a carrier

    SciTech Connect

    Liu, X.; Liu, D.

    1998-12-01

    A mathematical model is developed in this paper to simulate the facilitated transport of phenylalanine (Phe) in emulsion liquid membrane (ELM) systems with di(2-ethylhexyl)phosphoric acid as a carrier. The model takes into account the mass transfer in both the external aqueous phase and the organic membrane phase interfacial reaction as well as membrane breakage during agitation. The model is tested by comparing theoretical predications with experimental results using Phe extraction by ELM processes. It is found that the model is valid for simulating the facilitated transport of Phe with ELM under various experimental conditions.

  15. A Novel Submicron Emulsion System Loaded with Doxorubicin Overcome Multi-Drug Resistance in MCF-7/ADR Cells

    PubMed Central

    Zhou, W. P.; Hua, H. Y.; Sun, P. C.; Zhao, Y. X.

    2015-01-01

    The purpose of the present study was to develop the Solutol HS15-based doxorubicin submicron emulsion with good stability and overcoming multi-drug resistance. In this study, we prepared doxorubicin submicron emulsion, and examined the stability after autoclaving, the in vitro cytotoxic activity, the intracellular accumulation and apoptpsis of doxorubicin submicron emulsion in MCF-7/ADR cells. The physicochemical properties of doxorubicin submicron emulsion were not significantly affected after autoclaving. The doxorubicin submicron emulsion significantly increased the intracellular accumulation of doxorubicin submicron emulsion and enhanced cytotoxic activity and apoptotic effects of doxorubicin. These results may be correlated to doxorubicin submicron emulsion inhibitory effects on efflux pumps through the progressive release of intracellular free Solutol HS15 from doxorubicin submicron emulsion. Furthermore, these in vitro results suggest that the Solutol HS15-based submicron emulsion may be a potentially useful drug delivery system to circumvent multi-drug resistance of tumor cells. PMID:26664069

  16. Oxidative stability of fish and algae oils containing long-chain polyunsaturated fatty acids in bulk and in oil-in-water emulsions.

    PubMed

    Frankel, Edwin N; Satué-Gracia, Teresa; Meyer, Anne S; German, J Bruce

    2002-03-27

    The oxidative stability of long-chain polyunsaturated fatty acid (PUFA) and docosahexaenoic acid (DHA)-containing fish and algae oils varies widely according to their fatty acid composition, the physical and colloidal states of the lipids, the contents of tocopherols and other antioxidants, and the presence and activity of transition metals. Fish and algal oils were initially much more stable to oxidation in bulk systems than in the corresponding oil-in-water emulsions. The oxidative stability of emulsions cannot, therefore, be predicted on the basis of stability data obtained with bulk long-chain PUFA-containing fish oils and DHA-containing algal oils. The relatively high oxidative stability of an algal oil containing 42% DHA was completely lost after chromatographic purification to remove tocopherols and other antioxidants. Therefore, this evidence does not support the claim that DHA-rich oils from algae are unusually stable to oxidation. Addition of ethylenediaminetetraacetic acid (EDTA) prevented oxidation of both fish and algal oil emulsions without added iron and at low iron:EDTA molar concentrations. EDTA, however, promoted the oxidation of the corresponding emulsions that contained high iron:EDTA ratios. Therefore, to be effective as a metal chelator, EDTA must be added at molar concentrations higher than that of iron to inhibit oxidation of foods containing long-chain PUFA from either fish or algae and fortified with iron.

  17. Effects of soybean oil emulsion and eicosapentaenoic acid on stress response and immune function after a severely stressful operation.

    PubMed Central

    Furukawa, K; Tashiro, T; Yamamori, H; Takagi, K; Morishima, Y; Sugiura, T; Otsubo, Y; Hayashi, N; Itabashi, T; Sano, W; Toyoda, Y; Nitta, H; Nakajima, N

    1999-01-01

    OBJECTIVE: To investigate the effects of soybean oil emulsion and oral or enteral administration of eicosapentaenoic acid (EPA) on stress response, cytokine production, protein metabolism, and immune function after surgery for esophageal cancer. SUMMARY BACKGROUND DATA: It has been reported that safflower oil, rich in n-6 polyunsaturated fatty acid (n-6 PUFA), affects the survival rate of septic animals and decreases the immune function. It has also been reported that the administration of fish oil, in contrast, reduces these stress responses and stress-induced immunosuppression. In humans, the effects of soybean oil emulsion and the administration of EPA on stress response and immune function after surgery have not been established. METHODS: Patients who underwent esophagectomy with thoracotomy were divided into three groups. Seven patients were fed by total parenteral nutrition (TPN) with soybean oil emulsion, which accounted for 20% of total calories. Seven patients were given oral or enteral administration of 1.8 g/day EPA, in addition to TPN with soybean oil emulsion. Nine patients served as the control group; these patients received fat-free TPN. Serum interleukin-6 (IL-6), C-reactive protein, concanavalin A (con A)- or phytohemagglutinin (PHA)-stimulated lymphocyte proliferation, natural killer cell activity, and stress hormones were measured. RESULTS: The postoperative level of serum IL-6 was significantly higher in the group receiving soybean oil emulsion than in the fat-free group. Oral or enteral supplementation of EPA with soybean oil emulsion significantly reduced the level of serum IL-6 compared with the patients receiving soybean oil emulsion. Con A- or PHA-stimulated lymphocyte proliferation decreased significantly on postoperative day 7 in all groups of patients. The supplementation of EPA with soybean oil emulsion significantly improved the lymphocyte proliferation and natural killer cell activity on postoperative day 21 compared with the group

  18. Effects of processing conditions on structural and functional parameters of whipped dairy emulsions containing various fatty acid compositions.

    PubMed

    Bazmi, A; Relkin, P

    2009-08-01

    An understanding of the effects of processing parameters can be applied to formulate emulsions with higher unsaturated fatty acid content. Emulsions using the typical ice cream formulation were produced by anhydrous milk fat alone or in a mixture with either olein or stearin at a 2:1 weight ratio. Effects of both pasteurization holding time (40 or 120 s at 80 degrees C) and aging time (ranging from 2 to 24 h) on the structural and whipping properties of the emulsions were studied. Effects of these processing conditions on emulsion structural characteristics were determined using laser light-scattering measurements, rheological properties, microscopic observations, and image analyses of the whipped emulsions. Furthermore, foaming properties of these emulsions were compared and discussed with regard to effects of both processing and composition on properties of the emulsions, such as thixotropy and sensitivity to shearing. We observed changes in fat globules when different pasteurization holding times were applied, but no changes in either apparent viscosity values or sensitivity to shearing were traceable. However, enrichment of milk fat with the olein fraction increased the whipping ability of the emulsions, as evaluated in terms of overrun and the homogeneity of air bubbles, whatever the aging time. The lowest monodispersity of air bubbles was observed in the formulation rich in stearin. After 24 h of aging, this formulation showed the same overrun as the emulsion made with anhydrous milk fat. Increasing the aging time decreased the overrun by approximately 30%, and increasing the pasteurization holding times decreased it by approximately 20%. In general, in our conditions, increasing the aging time and unsaturated fatty acid content reduced changes in the dynamic rheological and structural properties observed just after production of the emulsions, whatever the pasteurization holding time or fat composition applied.

  19. Modulation of lipid digestibility using structured emulsion-based delivery systems: comparison of in vivo and in vitro measurements.

    PubMed

    Li, Yan; Kim, Jonggun; Park, Yeonhwa; McClements, David Julian

    2012-05-01

    Emulsion-based delivery systems are finding increasing application to enhance the oral bioavailability of poorly water-soluble pharmaceuticals and nutraceuticals, and to control the biological fate of ingested lipids. These systems can be designed to encapsulate lipophilic components, and then release them at specific locations within the gastrointestinal tract. The current study evaluated the performance of four emulsion-based delivery systems with different structures: (A) conventional emulsions; (B) small microcluster emulsions; (C) large microcluster emulsions; (D) filled hydrogel beads. These systems were fabricated from protein-coated lipid droplets, alginate, and/or calcium. The mean diameters (d₄₃) of the particles in these systems were 0.36, 4.7, 200, and 510 μm, respectively. The fate of the delivery systems within the gastrointestinal tract was ascertained by introducing them into rat stomachs. Confocal microscopy showed that system D remained intact in the stomach, but systems A, B and C exhibited considerable disruption leading to droplet coalescence. No intact delivery systems were observed within the small intestine using optical microscopy. Gas chromatography analysis using a marker lipid (tridecanoic acid) demonstrated that absorption was increasingly inhibited as the size of the droplet-biopolymer complexes increased, i.e., A > B > C > D. These results are in good qualitative agreement with previous in vitro digestion studies using similar delivery systems. This study showed that an in vitro digestion model is a useful predictive tool for in vivo feeding studies, and that encapsulation is an effective strategy to control the fate of lipids within the gastrointestinal (GI) tract.

  20. Pickering interfacial catalysis for biphasic systems: from emulsion design to green reactions.

    PubMed

    Pera-Titus, Marc; Leclercq, Loïc; Clacens, Jean-Marc; De Campo, Floryan; Nardello-Rataj, Véronique

    2015-02-09

    Pickering emulsions are surfactant-free dispersions of two immiscible fluids that are kinetically stabilized by colloidal particles. For ecological reasons, these systems have undergone a resurgence of interest to mitigate the use of synthetic surfactants and solvents. Moreover, the use of colloidal particles as stabilizers provides emulsions with original properties compared to surfactant-stabilized emulsions, microemulsions, and micellar systems. Despite these specific advantages, the application of Pickering emulsions to catalysis has been rarely explored. This Minireview describes very recent examples of hybrid and composite amphiphilic materials for the design of interfacial catalysts in Pickering emulsions with special emphasis on their assets and challenges for industrially relevant biphasic reactions in fine chemistry, biofuel upgrading, and depollution.

  1. Are Water-in-Oil-Emulsions Suitable Model Systems for Cloud Glaciation?

    NASA Astrophysics Data System (ADS)

    Handle, Karl; Loerting, Thomas; Bogdan, Anatoli; Weiss, Fabian; Pummer, Bernhard; Grothe, Hinrich

    2013-04-01

    The technique of studying aqueous solutions emulsified in oil matrices is widely used in the scientific community as a model system for aqueous droplets in the atmosphere, e.g., in the context of ice nucleation and cloud glaciation. These studies are based on the assumption that the interaction between aqueous and oil phase is negligible. In this study we critically test the validity of this assumption by systematically varying the parameters of the emulsification procedure for the study of the freezing behaviour of dilute and concentrated solutions of organic acids, e.g., citric acid, and inorganic salts, e.g., ammonium sulphate. In particular we vary the type of oil, the type of surfactant, the water to oil ratio, the mixing time and the temperature, at which the emulsion is prepared. These emulsions are studied in the context of cloud glaciation by cooling to < 150 K and reheating to ambient temperature. We specifically check for the droplets sizes and distribution as well as imperfectly emulsified regions from optical microscopy observations, first and second freezing events, cold-crystallization upon heating, melting events and possible glass-transitions from differential scanning calorimetry experiments as well as for the phase mixtures and types of ice (cubic vs. hexagonal) formed by powder X-ray diffraction as a function of temperature. The results clearly show that not all emulsions behave alike in these experiments and that it is important to be aware about the possibility of the oil matrix interfering with the experiment, e.g., for oils that vitrify at atmospherically relevant temperatures.

  2. Enhancement of intragastric acid stability of a fat emulsion meal delays gastric emptying and increases cholecystokinin release and gallbladder contraction.

    PubMed

    Marciani, Luca; Wickham, Martin; Singh, Gulzar; Bush, Debbie; Pick, Barbara; Cox, Eleanor; Fillery-Travis, Annette; Faulks, Richard; Marsden, Charles; Gowland, Penny A; Spiller, Robin C

    2007-06-01

    Preprocessed fatty foods often contain calories added as a fat emulsion stabilized by emulsifiers. Emulsion stability in the acidic gastric environment can readily be manipulated by altering emulsifier chemistry. We tested the hypothesis that it would be possible to control gastric emptying, CCK release, and satiety by varying intragastric fat emulsion stability. Nine healthy volunteers received a test meal on two occasions, comprising a 500-ml 15% oil emulsion with 2.5% of one of two emulsifiers that produced emulsions that were either stable (meal A) or unstable (meal B) in the acid gastric environment. Gastric emptying and gallbladder volume changes were assessed by MRI. CCK plasma levels were measured and satiety scores were recorded. Meal B layered rapidly owing to fat emulsion breakdown. The gastric half-emptying time of the aqueous phase was faster for meal B (72 +/- 13 min) than for meal A (171 +/- 35 min, P < 0.008). Meal A released more CCK than meal B (integrated areas, respectively 1,095 +/- 244 and 531 +/- 111 pmol.min.l(-1), P < 0.02), induced a greater gallbladder contraction (P < 0.02), and decreased postprandial appetite (P < 0.05), although no significant differences were observed in fullness and hunger. We conclude that acid-stable emulsions delayed gastric emptying and increased postprandial CCK levels and gallbladder contraction, whereas acid-instability led to rapid layering of fat in the gastric lumen with accelerated gastric emptying, lower CCK levels, and reduced gallbladder contraction. Manipulation of the acid stability of fat emulsion added to preprocessed foods could maximize satiety signaling and, in turn, help to reduce overconsumption of calories.

  3. Role of naphthenic acids in stabilizing water-in-diluted model oil emulsions.

    PubMed

    Gao, Song; Moran, Kevin; Xu, Zhenghe; Masliyah, Jacob

    2010-06-17

    The need for alkaline conditions in oil sands processing is, in part, to produce natural surfactants from bitumen. Previous studies have shown that the produced surfactants are primarily carboxylic salts of naphthenic acids with the possibility of sulfonic salts as well. The role of these natural surfactants, particularly those in the naphthenate class, is to provide a physicochemical basis for several subprocesses in bitumen extraction. In this study, it was found that the content of indigenous naphthenic acids in bitumen can destabilize, to some extent, the water-in-oil emulsion by lowering the interfacial tension, reducing the rigidity and promoting the coalescence of water droplets.

  4. Study on the Stability of DeoxyArbutin in an Anhydrous Emulsion System

    PubMed Central

    Lin, Chih-Chien; Yang, Chao-Hsun; Chang, Nai-Fang; Wu, Pey-Shiuan; Chen, Yi-Shyan; Lee, Shu-Mei; Chen, Chiu-Wen

    2011-01-01

    The skin-whitening agent, deoxyArbutin, is a potent tyrosinase inhibitor that is safer than hydroquinone and arbutin. However, it is thermolabile in aqueous solutions, where it decomposes to hydroquinone. Pharmaceutical and cosmetic emulsions are normally oil-in-water (o/w) or water-in-oil (w/o) systems; however, emulsions can be formulated with no aqueous phase to produce an anhydrous emulsion system. An anhydrous emulsion system could offer a stable vehicle for compounds that are sensitive to hydrolysis or oxidation. Therefore, to enhance the stability of deoxyArbutin in formulations, we chose the polyol-in-silicone, anhydrous emulsion system as the basic formulation for investigation. The quantity of deoxyArbutin and the accumulation of hydroquinone in both hydrous and anhydrous emulsions at various temperatures were analyzed through an established high performance liquid chromatographic (HPLC) method. The results indicated that water increased the decomposition of deoxyArbutin in the formulations and that the polyol-in-silicone, oil-based, anhydrous emulsion system provided a relatively stable surrounding for the deoxyArbutin that delayed its degradation at 25 °C and 45 °C. Moreover, the composition of the inner hydrophilic phase, containing different amounts of glycerin and propylene glycol, affected the stability of deoxyArbutin. Thus, these results will be beneficial when using deoxyArbutin in cosmetics and medicines in the future. PMID:22016637

  5. Aluminum contamination of parenteral nutrition additives, amino acid solutions, and lipid emulsions.

    PubMed

    Popińska, K; Kierkuś, J; Lyszkowska, M; Socha, J; Pietraszek, E; Kmiotek, W; Ksiazyk, J

    1999-09-01

    Contamination of parenteral nutrition solutions with aluminum may result in accumulation of this element in bones and, in premature infants, may inhibit bone calcium uptake and induce cholestasis. We measured the aluminum concentration of small-volume parenterals, amino acid solutions, lipid emulsions, and special solutions containing glucose, amino acids, electrolytes, and trace elements (standard I for children with a body weight of 3-5 kg, standard II for children with a body weight of 5-10 kg). The method used was graphite furnace atomic absorption spectrometry GTA-AAS (SpectrAA-400 Plus, Varian, PtY Ltd., Mulgrave, Australia). Quality control was run with the use of control serum (Seronorm, Nycomed, Oslo, Norway). The aluminum contents of parenterally administered solutions were: pediatric trace elements, 130 micrograms/L, and pediatric trace elements, 3000 micrograms/L; phosphorus salts: K-phosphates, 9800 micrograms/L, and Na/K phosphates, 13,000 micrograms/L; 10% calcium gluconate, 4400 micrograms/L; 6.5% amino acids, 30 micrograms/L; 10% amino acids, 120 micrograms/L; 12.5% amino acids, 121 micrograms/L; 20% lipid emulsion, 30 micrograms/L; 20% lipid emulsion, 180 micrograms/L; water-soluble vitamins, 12 micrograms/L; lipid soluble vitamins, 360 micrograms/L; standard I, 55 micrograms/L; standard II, 90 micrograms/L; The aluminum intake from parenteral nutrition was 6.6-10.8 micrograms.kg-1.d-1--a dose exceeding the safety limit of 2 micrograms.kg-1.d-1. The possible association of aluminum not only with metabolic bone disease, but also with encephalopathy, dictates caution when dealing with the pediatric population on long-term parenteral nutrition. In the absence of reliable label information, it seems proper to monitor the aluminum concentration in parenteral nutrition products and to report it in professional journals.

  6. Interfacial engineering using mixed protein systems: emulsion-based delivery systems for encapsulation and stabilization of β-carotene.

    PubMed

    Mao, Yingyi; Dubot, Marie; Xiao, Hang; McClements, David Julian

    2013-05-29

    Emulsion-based delivery systems are needed to encapsulate, protect, and deliver lipophilic bioactive components in the food, personal care, and pharmaceutical industries. The functional performance of these systems can be controlled by engineering the composition and structure of the interfacial layer coating the lipid droplets. In this study, interfacial properties were controlled using two globular proteins with widely differing isoelectric points: lactoferrin (LF: pI ≈ 8.5) and β-lactoglobulin (BLG: pI ≈ 5). Oil-in-water emulsions were prepared with different interfacial properties: [LF]-only; [BLG]-only; [LF]-[BLG]-(laminated); [BLG]-[LF]-(laminated); and [BLG/LF]-(mixed). The influence of pH, ionic strength, and temperature on the physical stability of β-carotene-enriched emulsions was investigated. [LF]-emulsions were stable to droplet aggregation from pH 2 to 9 (0 mM NaCl), but all other emulsions aggregated at intermediate pH values. [BLG]-emulsions aggregated at high salt levels (≥50 mM NaCl), but all other emulsions were stable (0 to 300 mM NaCl). [BLG/LF]-emulsions were unstable to heating (≥60 °C), but all other emulsions were stable (30 to 90 °C). Color fading due to β-carotene degradation occurred relatively quickly in [BLG]-emulsions (37 °C) but was considerably lower in all other emulsions, which was attributed to the ability of LF to bind iron or interact with β-carotene. This study provides useful information for designing emulsion-based delivery systems to encapsulate and protect bioactive lipids, such as carotenoids.

  7. Influence of droplet size on the antioxidant activity of rosemary extract loaded oil-in-water emulsions in mixed systems.

    PubMed

    Erdmann, Martin E; Zeeb, Benjamin; Salminen, Hanna; Gibis, Monika; Lautenschlaeger, Ralf; Weiss, Jochen

    2015-03-01

    The influence of droplet size on the antioxidant activity of oil-in-water emulsions loaded with rosemary extract in mixed emulsion systems was investigated. Firstly, differently sized hexadecane-in-water model emulsions (10% (w/w) hexadecane, 2% (w/w) Tween 80, pH 5 or 7) containing 4000 ppm rosemary extract in the oil phase or without added antioxidant were prepared using a high shear blender and/or high-pressure homogenizer. Secondly, emulsions were mixed with fish oil-in-water emulsions (10% (w/w) fish oil, 2% (w/w) Tween 80, pH 5 or 7) at a mixing ratio of 1 : 1. Optical microscopy and static light scattering measurements indicated that emulsions were physically stable for 21 days, except for the slight aggregation of emulsions with a mean droplet size d₄₃ of 4500 nm. The droplet size of hexadecane-in-water emulsions containing rosemary extract had no influence on the formation of lipid hydroperoxides at pH 5 and 7. Significantly lower concentrations of propanal were observed for the emulsions loaded with rosemary extract with a mean droplet size d₄₃ of 4500 nm from day 12 to 16 at pH 7. Finally, hexadecane-in-water emulsions containing rosemary extract significantly retarded lipid oxidation of fish oil-in-water emulsions in mixed systems, but no differences in antioxidant efficacy between the differently sized emulsions were observed at pH 5.

  8. Emulsion polymerization of polystyrene-co-acrylic acid with Cu2O incorporation

    NASA Astrophysics Data System (ADS)

    Fahmiati, Sri; Harmami, Sri Budi; Meliana, Yenny; Haryono, Agus

    2017-01-01

    In this research, poly(styrene-co-acrylic acid-Cu) was prepared via emulsion polymerization.Cu contents were varied as 10%, 15% and 20% and mol ratio of styrene to acrylic acid as 1:1 and 2:1. Structure and surface of poly(styrene-co-acrylic acid-Cu) were characterized by FTIR (Fourier Transformed Infra Red), NMR (Nuclear Magnetic Resonance), and SEM/EDX (Scanning Electron Microcope/ Energy Dispersive X-Ray) spectroscopy. The NMR spectra showed that the polymer was formed, however FTIR spectra showed that there were still unreacted monomers. SEM-EDX confirmed that copper (Cu) was dispersed uniformly on poly(styrene-co-acrylic acid-Cu) matrix.

  9. In vivo studies of polyacrylate nanoparticle emulsions for topical and systemic applications.

    PubMed

    Greenhalgh, Kerriann; Turos, Edward

    2009-03-01

    We have recently reported on a new nanomedicine containing antibiotic-conjugated polyacrylate nanoparticles, which has shown activity against methicillin-resistant Staphylococcus aureus (MRSA) in vitro and no cytotoxicity toward human dermal cells. The water-based nanoparticle emulsion is capable of solubilizing lipophilic antibiotics for systemic administration, and the nanoparticle drug delivery vehicle has shown protective properties for antibiotics from hydrolytic cleavage by bacterial penicillinases, thus rejuvenating the drug's activity against resistant microbes such as MRSA. Here we report the first in vivo study of this penicillin-conjugated nanoparticle emulsion in determining toxicological responses initiated upon systemic and topical application in a murine model. Favorable results were observed in vivo upon both routes of administration and, when topically applied to a dermal abrasion model, the emulsion enhanced wound healing by an average of 3 to 5 days. This study suggests that polyacrylate nanoparticle-containing emulsions may afford promising opportunities for treating both skin and systemic infections.

  10. Recovery of organic extractant from secondary emulsions formed in the extraction of uranium from wet-process phosphoric acid

    SciTech Connect

    Korchnak, J.D.; Fett, R.H.G.

    1984-01-03

    Uranium in wet-process phosphoric acid is extracted with an organic extractant. The pregnant extractant is then centrifuged to separate contaminants from the extractant. Secondary emulsions obtained by separating the contaminants following centrifugation are mixed with water or an acid leaching solution. After mixing, the mixture is centrifuged to separate and recover extractant which is recycled for stripping.

  11. Antioxidant activity of phenolic compounds added to a functional emulsion containing omega-3 fatty acids and plant sterol esters.

    PubMed

    Espinosa, Raquel Rainho; Inchingolo, Raffaella; Alencar, Severino Matias; Rodriguez-Estrada, Maria Teresa; Castro, Inar Alves

    2015-09-01

    The effect of eleven compounds extracted from red propolis on the oxidative stability of a functional emulsion was evaluated. Emulsions prepared with Echium oil as omega 3 (ω-3 FA) source, containing 1.63 g/100mL of α-linolenic acid (ALA), 0.73 g/100 mL of stearidonic acid (SDA) and 0.65 g/100mL of plant sterol esters (PSE) were prepared without or with phenolic compounds (vanillic acid, caffeic acid, trans-cinnamic acid, 2,4-dihydroxycinnamic acid, p-coumaric acid, quercetin, trans-ferulic acid, trans,trans-farnesol, rutin, gallic acid or sinapic acid). tert-Butylhydroquinone and a mixture containing ascorbic acid and FeSO4 were applied as negative and positive controls of the oxidation. Hydroperoxide, thiobarbituric acid reactive substances (TBARS), malondialdehyde and phytosterol oxidation products (POPs) were evaluated as oxidative markers. Based on hydroperoxide and TBARS analysis, sinapic acid and rutin (200 ppm) showed the same antioxidant activity than TBHQ, representing a potential alternative as natural antioxidant to be applied in a functional emulsion containing ω-3 FA and PSE.

  12. A new fast scanning system for the measurement of large angle tracks in nuclear emulsions

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Buonaura, A.; Consiglio, L.; D'Ambrosio, N.; De Lellis, G.; Di Crescenzo, A.; Di Marco, N.; Galati, G.; Lauria, A.; Montesi, M. C.; Pupilli, F.; Shchedrina, T.; Tioukov, V.; Vladymyrov, M.

    2015-11-01

    Nuclear emulsions have been widely used in particle physics to identify new particles through the observation of their decays thanks to their unique spatial resolution. Nevertheless, before the advent of automatic scanning systems, the emulsion analysis was very demanding in terms of well trained manpower. Due to this reason, they were gradually replaced by electronic detectors, until the '90s, when automatic microscopes started to be developed in Japan and in Europe. Automatic scanning was essential to conceive large scale emulsion-based neutrino experiments like CHORUS, DONUT and OPERA. Standard scanning systems have been initially designed to recognize tracks within a limited angular acceptance (θ lesssim 30°) where θ is the track angle with respect to a line perpendicular to the emulsion plane. In this paper we describe the implementation of a novel fast automatic scanning system aimed at extending the track recognition to the full angular range and improving the present scanning speed. Indeed, nuclear emulsions do not have any intrinsic limit to detect particle direction. Such improvement opens new perspectives to use nuclear emulsions in several fields in addition to large scale neutrino experiments, like muon radiography, medical applications and dark matter directional detection.

  13. Encapsulation of Polymethoxyflavones in Citrus Oil Emulsion-Based Delivery Systems.

    PubMed

    Yang, Ying; Zhao, Chengying; Chen, Jingjing; Tian, Guifang; McClements, David Julian; Xiao, Hang; Zheng, Jinkai

    2017-03-01

    The purpose of this work was to elucidate the effects of citrus oil type on polymethoxyflavone (PMF) solubility and on the physicochemical properties of PMF-loaded emulsion-based delivery systems. Citrus oils were extracted from mandarin, orange, sweet orange, and bergamot. The major constituents were determined by GC/MS: sweet orange oil (97.4% d-limonene); mandarin oil (72.4% d-limonene); orange oil (67.2% d-limonene); and bergamot oil (34.6% linalyl acetate and 25.3% d-limonene). PMF-loaded emulsions were fabricated using 10% oil phase (containing 0.1% w/v nobiletin or tangeretin) and 90% aqueous phase (containing 1% w/v Tween 80) using high-pressure homogenization. Delivery systems prepared using mandarin oil had the largest mean droplet diameters (386 or 400 nm), followed by orange oil (338 or 390 nm), bergamot oil (129 or 133 nm), and sweet orange oil (122 or 126 nm) for nobiletin- or tangeretin-loaded emulsions, respectively. The optical clarity of the emulsions increased with decreasing droplet size due to reduced light scattering. The viscosities of the emulsions (with or without PMFs) were similar (1.3 to 1.4 mPa·s), despite appreciable differences in oil phase viscosity. The loading capacity and encapsulation efficiency of the emulsions depended on carrier oil type, with bergamot oil giving the highest loading capacity. In summary, differences in the composition and physical characteristics of citrus oils led to PMF-loaded emulsions with different encapsulation and physicochemical characteristics. These results will facilitate the rational design of emulsion-based delivery systems for encapsulation of PMFs and other nutraceuticals in functional foods and beverages.

  14. Pickering Emulsion Gels Prepared by Hydrogen-Bonded Zein/Tannic Acid Complex Colloidal Particles.

    PubMed

    Zou, Yuan; Guo, Jian; Yin, Shou-Wei; Wang, Jin-Mei; Yang, Xiao-Quan

    2015-08-26

    Food-grade colloidal particles and complexes, which are formed via modulation of the noncovalent interactions between macromolecules and natural small molecules, can be developed as novel functional ingredients in a safe and sustainable way. For this study was prepared a novel zein/tannic acid (TA) complex colloidal particle (ZTP) based on the hydrogen-bonding interaction between zein and TA in aqueous ethanol solution by using a simple antisolvent approach. Pickering emulsion gels with high oil volume fraction (φ(oil) > 50%) were successfully fabricated via one-step homogenization. Circular dichroism (CD) and small-angle X-ray scattering (SAXS) measurements, which were used to characterize the structure of zein/TA complexes in ethanol solution, clearly showed that TA binding generated a conformational change of zein without altering their supramolecular structure at pH 5.0 and intermediate TA concentrations. Consequently, the resultant ZTP had tuned near neutral wettability (θ(ow) ∼ 86°) and enhanced interfacial reactivity, but without significantly decreased surface charge. These allowed the ZTP to stabilize the oil droplets and further triggered cross-linking to form a continuous network among and around the oil droplets and protein particles, leading to the formation of stable Pickering emulsion gels. Layer-by-layer (LbL) interfacial architecture on the oil-water surface of the droplets was observed, which implied a possibility to fabricate hierarchical interface microstructure via modulation of the noncovalent interaction between hydrophobic protein and natural polyphenol.

  15. Asphalt emulsion radon barrier systems for uranium mill tailings: an overview of the technology

    SciTech Connect

    Baker, E.G.; Hartley, J.N.; Freeman, H.D.; Gates, T.E.; Nelson, D.A.; Dunning, R.L.

    1984-03-01

    Pacific Northwest Laboratory (PNL), under contract to the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) office, has developed an asphalt emulsion cover system to reduce the release of radon from uranium mill tailings. The system has been field tested at Grand Junction, Colorado. Results from laboratory and field tests indicate that this system is effective in reducing radon release to near-background levels (<2.5 pCi m/sup -2/s/sup -1/) and has the properties required for long-term effectiveness and stability. Engineering specifications have been developed, and analysis indicates that asphalt emulsion covers are cost-competitive with other cover systems. This report summarizes the technology for asphalt emulsion radon barrier systems. 59 references, 45 figures, 36 tables.

  16. Bond Graph Modeling and Validation of an Energy Regenerative System for Emulsion Pump Tests

    PubMed Central

    Li, Yilei; Zhu, Zhencai; Chen, Guoan

    2014-01-01

    The test system for emulsion pump is facing serious challenges due to its huge energy consumption and waste nowadays. To settle this energy issue, a novel energy regenerative system (ERS) for emulsion pump tests is briefly introduced at first. Modeling such an ERS of multienergy domains needs a unified and systematic approach. Bond graph modeling is well suited for this task. The bond graph model of this ERS is developed by first considering the separate components before assembling them together and so is the state-space equation. Both numerical simulation and experiments are carried out to validate the bond graph model of this ERS. Moreover the simulation and experiments results show that this ERS not only satisfies the test requirements, but also could save at least 25% of energy consumption as compared to the original test system, demonstrating that it is a promising method of energy regeneration for emulsion pump tests. PMID:24967428

  17. The effects of emulsifying agents on disposition of lipid-soluble drugs included in fat emulsion.

    PubMed

    Suzuki, Yasuyuki; Masumitsu, Yasushi; Okudaira, Kazuho; Hayashi, Masahiro

    2004-02-01

    The uses for drug delivery systems of two soybean oil fat emulsions prepared with an emulsifying agent, phosphatidyl choline (PC) or Pluronic F-127 (PLU), were examined comparatively in vivo and in vitro. In the presence of lipoprotein lipase (LPL) in vitro, the mean particle size of the PLU emulsion changed less than that of the PC emulsion. The production of non-esterified fatty acid (NEFA) from the PLU emulsion in the presence of LPL was smaller than that from the PC emulsion. These in vitro results indicate that the PLU emulsion is more stable than the PC emulsion. Plasma NEFA concentration following intravenous administration of the emulsions decreased with time for the PC emulsion, but was kept lower and constant for the PLU emulsion, supporting the in vitro stability data. The order of plasma cyclosporine A (CsA) concentration following intravenous administration in the above two emulsions and the mixed solution of polyethylene glycol 400 (PEG) and dimethylamide (DMA) in rats was PLU emulsion>PC emulsion>PEG/DMA solution. The plasma concentration was maintained higher and tissue distribution lower for the PLU emulsion than for other formulations. The uptake of oil violet (OV) into the rat parenchymal cells from the PLU emulsion was approximately half that from the PC emulsion, but the uptake into the Kupffer cells was almost equal in both emulsions. In conclusion, these emulsifying agents can control plasma elimination and tissue distribution of lipophilic drugs included in the emulsion. The use of the emulsion formulation makes it possible to avoid side effects through the reduction of drug uptake into non-targeted tissues.

  18. Viscosity of the oil-in-water Pickering emulsion stabilized by surfactant-polymer and nanoparticle-surfactant-polymer system

    NASA Astrophysics Data System (ADS)

    Sharma, Tushar; Kumar, G. Suresh; Chon, Bo Hyun; Sangwai, Jitendra S.

    2014-11-01

    Information on the viscosity of Pickering emulsion is required for their successful application in upstream oil and gas industry to understand their stability at extreme environment. In this work, a novel formulation of oil-in-water (o/w) Pickering emulsion stabilized using nanoparticle-surfactant-polymer (polyacrylamide) system as formulated in our earlier work (Sharma et al., Journal of Industrial and Engineering Chemistry, 2014) is investigated for rheological stability at high pressure and high temperature (HPHT) conditions using a controlled-strain rheometer. The nanoparticle (SiO2 and clay) concentration is varied from 1.0 to 5.0 wt%. The results are compared with the rheological behavior of simple o/w emulsion stabilized by surfactant-polymer system. Both the emulsions exhibit non-Newtonian shear thinning behavior. A positive shift in this behavior is observed for surfactant-polymer stabilized emulsion at high pressure conditions. Yield stress is observed to increase with pressure for surfactant-polymer emulsion. In addition, increase in temperature has an adverse effect on the viscosity of emulsion stabilized by surfactant-polymer system. In case of nanoparticle-surfactant-polymer stabilized o/w emulsion system, the viscosity and yield stress are predominantly constant for varying pressure and temperature conditions. The viscosity data for both o/w emulsion systems are fitted by the Herschel-Bulkley model and found to be satisfactory. In general, the study indicates that the Pickering emulsion stabilized by nanoparticle-surfactant-polymer system shows improved and stable rheological properties as compared to conventional emulsion stabilized by surfactant-polymer system indicating their successful application for HPHT environment in upstream oil and gas industry.

  19. Charge Identification of Highly Ionizing Particles in Desensitized Nuclear Emulsion Using High Speed Read-Out System

    SciTech Connect

    Toshito, T.; Kodama, K.; Yusa, K.; Ozaki, M.; Amako, K.; Kameoka, S.; Murakami, K.; Sasaki, T.; Aoki, S.; Ban, T.; Fukuda, T.; Naganawa, N.; Nakamura, T.; Natsume, M.; Niwa, K.; Takahashi, S.; Kanazawa, M.; Kanematsu, N.; Komori, M.; Sato, S.; Asai, M.; /Nagoya U. /Aichi U. of Education /Gunma U., Maebashi /JAXA, Sagamihara /KEK, Tsukuba /Kobe U. /Chiba, Natl. Inst. Rad. Sci. /SLAC /Toho U.

    2006-05-10

    We performed an experimental study of charge identification of heavy ions from helium to carbon having energy of about 290 MeV/u using an emulsion chamber. Emulsion was desensitized by means of forced fading (refreshing) to expand a dynamic range of response to highly charged particles. For the track reconstruction and charge identification, the fully automated high speed emulsion read-out system, which was originally developed for identifying minimum ionizing particles, was used without any modification. Clear track by track charge identification up to Z=6 was demonstrated. The refreshing technique has proved to be a powerful technique to expand response of emulsion film to highly ionizing particles.

  20. Preparation of novel silicone multicompartment particles by multiple emulsion templating and their use as encapsulating systems.

    PubMed

    Vilanova, Neus; Solans, Conxita; Rodríguez-Abreu, Carlos

    2013-12-10

    Multicompartment poly(dimethylsiloxane) particles were produced for the first time using water-in-oil-in-water (W1/O/W2) emulsions as templates. Multiple silicone W1/O/W2 emulsions were successfully prepared by using silicone precursors with a low viscosity. Several formulation parameters were studied to determine their effect on the properties of emulsions and derived particles. It was observed that the mass fraction of the inner aqueous phase (φ(W1)) and the concentration of both the hydrophobic and hydrophilic surfactants played a crucial role in the morphology and stability of the emulsions. Thus, the derived silicone porous particles also showed different characteristics depending on the emulsion formulation because of the templating effect. At low φ(W1) or high concentrations of the hydrophobic surfactant, particles showed smaller pore sizes as a result of more stable inner droplets. On the other hand, high concentrations of the hydrophobic surfactant resulted in an increase in the size of the derived particles, whereas high concentrations of the hydrophilic surfactant caused the opposite effect. In addition, fluorescein was encapsulated into the hydrophobic particles during the synthesis process and released in a controlled manner. The possibility to encapsulate simultaneously but independently two different hydrophilic components inside the same globule was also tested. On the basis of these results, the obtained silicone porous particles are envisioned to have applications in several advanced fields, for instance, as hydrophobic delivery systems.

  1. Thermal reversibility of vitamin E-enriched emulsion-based delivery systems produced using spontaneous emulsification.

    PubMed

    Saberi, Amir Hossein; Fang, Yuan; McClements, David Julian

    2015-10-15

    The influence of temperature scanning and isothermal storage conditions on turbidity, particle size, and thermal reversibility of vitamin E-enriched emulsions produced by spontaneous emulsification was examined. Initially, the mini-emulsions formed were optically transparent and contained small droplets (d ≈ 44 nm). When heated (20-90 °C), emulsions exhibited a complex turbidity-temperature profile with a phase inversion temperature (PIT) at ≈ 75-80 °C. Temperature scanning rate had a major influence on emulsion thermal reversibility. Slow heating (0.5 °C/min) above the PIT followed by quench cooling (≈ 67 °C min(-1)) to 30 °C did not appreciably increase turbidity or droplet diameter (d ≈ 50 nm), suggesting these systems were thermo-reversible. However, slow heating to temperatures below the PIT followed by rapid cooling appreciably increased droplet size and turbidity (thermo-irreversible). Cooling rate also affected emulsion thermo-reversibility: the turbidity and droplet size after heating above the PIT decreased with increasing cooling rate.

  2. Comparing the moisturizing effects of ascorbic acid and calcium ascorbate against that of tocopherol in emulsions.

    PubMed

    Gönüllü, U; Sensoy, D; Uner, M; Yener, G; Altinkurt, T

    2006-01-01

    Calcium ascorbate (CAAS), which is a hydrophilic and stable derivative of ascorbic acid (vitamin C) (AA), is commonly used in foods as an antioxidative agent. There are very limited reports on its dermatological use in the literature. In this paper, it is reported that CAAS could be used in place of ascorbic acid, which has chemical stability problems in topicals due to degradation by oxidation. The aim of this study was to investigate the skin-hydrating effect of CAAS compared to those of ascorbic acid and tocopherol (vitamin E) (T), which is a potential skin moisturizer and commonly used in dermocosmetics. Vitamins are incorporated into two kinds of base creams (o/w and w/o emulsion creams), alone and in combinations. Formulations were applied to the inner forearms of volunteers, and skin conductance was measured by using a corneometer. Data obtained were statistically evaluated. It was found that the skin-hydrating effect of CAAS was higher than that of AA and lower than that of T. However, its effect was very close to that of T.

  3. Validation of HPLC-UV Assay of Caffeic Acid in Emulsions.

    PubMed

    Spagnol, Caroline Magnani; Isaac, Vera Lucia Borges; Corrêa, Marcos Antonio; Salgado, Hérida Regina Nunes

    2016-03-01

    An accurate, sensitive, precise and rapid reversed-phase high-performance liquid chromatographic method was successfully developed and validated for the determination of caffeic acid (CA) in emulsions. The best separation was achieved on a 250 × 4.6 mm, 5.0 µm particle size RP18 XDB Waters column using ethanol and purified water (40:60 v/v) adjusted to pH 2.5 with acetic acid as the mobile phase at a flow rate of 0.7 mL/min. Ultraviolet detection was performed at 325 nm at ambient column temperature (25°C). The method was linear over the concentration range of 10-60 µg/mL (r(2) = 0.9999) with limits of detection and quantification of 1.44 and 4.38 µg/mL, respectively. CA was subjected to oxidation, acid, base and neutral degradation, as well as photolysis and heat as stress conditions. There were no interfering peaks at or near the retention time of CA. The method was applied to the determination of CA in standard and pharmaceutical products with excellent recoveries. The method is applicable in the quality control of CA.

  4. Dynamic film and interfacial tensions in emulsion and foam systems

    SciTech Connect

    Kim, Y.H.; Koczo, K.; Wasan, D.T.

    1997-03-01

    In concentrated fluid dispersions the liquid films are under dynamic conditions during film rupture or drainage. Aqueous foam films stabilized with sodium decylsulfonate and aqueous emulsion films stabilized with the nonionic Brij 58 surfactant were formed at the tip of a capillary and the film tension was measured under static and dynamic conditions. In the stress relaxation experiments the response of the film tension to a sudden film area expansion was studied. These experiments also allowed the direct measurement of the Gibbs film elasticity. In the dynamic film tension experiments, the film area was continuously increased by a constant rate and the dynamic film tension was monitored. The measured film tensions were compared with the interfacial tensions of the respective single air/water and oil/water interfaces, which were measured using the same radius of curvature, relative expansion, and expansion rate as in the film studies. It was found that under dynamic conditions the film tension is higher than twice the single interfacial tension (IFT) and a mechanism was suggested to explain the difference. When the film, initially at equilibrium, is expanded and the interfacial area increases, a substantial surfactant depletion occurs inside the film. As a result, the surfactant can be supplied only from the adjoining meniscus (Plateau border) by surface diffusion, and the film tension is controlled by the diffusion and adsorption of surfactant in the meniscus. The results have important implications for the stability and rheology of foams and emulsions with high dispersed phase ratios (polyhedral structure).

  5. Impact of emulsion-based drug delivery systems on intestinal permeability and drug release kinetics.

    PubMed

    Buyukozturk, Fulden; Benneyan, James C; Carrier, Rebecca L

    2010-02-25

    Lipid based drug delivery systems, and in particular self-emulsifying drug delivery systems (SEDDS), show great potential for enhancing oral bioavailability but have not been broadly applied, largely due to lack of general formulation guidance. To help understand how formulation design influences physicochemical emulsion properties and associated function in the gastrointestinal environment, a range of twenty-seven representative self-emulsifying formulations were investigated. Two key functions of emulsion-based drug delivery systems, permeability enhancement and drug release, were studied and statistically related to three formulation properties - oil structure, surfactant hydrophilic liphophilic balance (HLB) values, and surfactant-to-oil ratio. Three surfactants with HLB values ranging from 10 to 15 and three structurally different oils (long chain triglyceride, medium chain triglyceride, and propylene glycol dicaprylate/dicaprate) were combined at three different weight ratios (1:1, 5:1, 9:1). Unstable formulations of low HLB surfactant (HLB=10) had a toxic effect on cells at high (1:1) surfactant concentrations, indicating the importance of formulation stability for minimizing toxicity. Results also indicate that high HLB surfactant (Tween 80) loosens tight junction at high (1:1) surfactant concentrations. Release coefficients for each emulsion system were calculated. Incorporation of a long chain triglyceride (Soybean oil) as the oil phase increased the drug release rate constant. These results help establish an initial foundation for relating emulsion function to formulation design and enabling bioavailability optimization across a broad, representative range of SEDDS formulations.

  6. Evaluation of HLB values of mixed non-ionic surfactants on the stability of oil-in-water emulsion system

    NASA Astrophysics Data System (ADS)

    Nursakinah, I.; Ismail, A. R.; Rahimi, M. Y.; Idris, A. B.

    2013-11-01

    Emulsion oil-in-water was prepared with combination of emulsifiers (non-ionic surfactants) following the HLB (hydrophylic-lipophylic balance) method developed by Griffin. The emulsions were prepared at HLB 10, 11, 12, 13 and 13.6 consisting blend of non-ionic emulsifiers fatty acid ethoxylate with 20 moles bound ethylene oxide and Dehydol LS 1 with 1 mole bound ethylene oxide. A mixture of palm-based methyl ester consisting of C6-10 and C12-18 fatty acid composition was used as palm-based solvent. The physicochemical parameters of the emulsion were characterized by accelerate stability tested at 45°C for two months, measurement of particle size and viscosity test. The result of accelerate test showed that all the emulsion at different HLB were found to be stable in the 2 months observation which assumed to be stable in 1 year of storage. Meanwhile, the particle size measurement data showed that the optimum stable particle size of the emulsion was HLB 12±1. The viscosity test of the emulsion tends to support the data from the particle size and have maximum viscosity 189.89 cP at HLB 12. The obtained results indicate that the optimum stable emulsions can be formulated by a combination of emulsifiers with HLB 12±1 which is compatible with that of required HLB of the oil phase.

  7. Stability assessment of conjugated linoleic acid (CLA) oil-in-water beverage emulsion formulated with acacia and xanthan gums.

    PubMed

    Nikbakht Nasrabadi, Maryam; Goli, Sayed Amir Hossein; Nasirpour, Ali

    2016-05-15

    The development of a conjugated linoleic acid (CLA) oil-in-water beverage emulsion containing acacia gum (AG) and xanthan gum (XG) was investigated. D-optimal design and response surface method was used and 10% w/w AG, 3.5% w/w CLA and 0.3% w/w XG was introduced as the optimum formula. Afterward the effect of storage time on the physicochemical properties of selected formulation including specific gravity, turbidity, viscosity, average droplet size, span, size index, creaming index, oxidation measurements and stability in its diluted form, were determined. Findings revealed that the size of oil droplets increased after six weeks and resulted in instability of the emulsion concentrate. Peroxide value increased until 21 days and then decreased dramatically, whereas TBA and Totox values began to increase after this time. Turbidity loss rate was low demonstrating the good stability of the diluted emulsion. The results revealed that it is possible to produce a stable CLA oil-in-water emulsion for using in beverages.

  8. Pharmacopeial compliance of fish oil-containing parenteral lipid emulsion mixtures: Globule size distribution (GSD) and fatty acid analyses.

    PubMed

    Driscoll, David F; Ling, Pei-Ra; Bistrian, Bruce R

    2009-09-08

    Recently, the United States Pharmacopeia (USP) has established Chapter 729 with GSD limits for all lipid emulsions where the mean droplet size (MDS) must be <500 nm and the percent of fat larger than 5 microm (PFAT(5)) must be <0.05%, irrespective of the final lipid concentration. As well, the European Pharmacopeia (EP) Monograph no. 1352 specifies n3-fatty acid (FA) limits (EPA+DHA> or =45%; total n3 or T-n3> or =60%) for fish oil. We assessed compliance with USP physical and EP chemical limits of two fish oil-containing lipid emulsion mixtures. All lipid emulsions passed USP 729 limits. No samples tested had an MDS >302 nm or a PFAT(5) value >0.011%. Only one product met EP limits while the other failed. All emulsions tested were extremely fine dispersions and easily met USP 729 GSD limits. The n3-FAs profiles were lower in one, despite being labeled to contain 50% more fish oil than the other product. This latter finding suggests the n3-FA content of the fish oil source and/or the applied manufacturing processes in these products is different.

  9. High pressure inactivation of Clostridium botulinum type E endospores in model emulsion systems

    NASA Astrophysics Data System (ADS)

    Schnabel, Juliane; Lenz, Christian A.; Vogel, Rudi F.

    2015-01-01

    Clostridium botulinum type E is a cold-tolerant, neurotoxigenic, endospore-forming organism, primarily associated with aquatic environments. High pressure thermal (HPT) processing presents a promising tool to enhance food safety and stability. The effect of fat on HPT inactivation of C. botulinum type E spores was investigated using an emulsion model system. The distribution of spores in oil-in-water (O/W) emulsions and their HPT (300-750 MPa, 45-75 °C, 10 min) inactivation was determined as a function of emulsion fat content (30-70% (v/v) soybean oil in buffer). Approximately 26% and 74% of the spores were located at the oil-buffer interface and the continuous phase, respectively. Spore inactivation in emulsion systems decreased with increasing oil contents, which suggests that the fat content of food plays an important role in the protection of C. botulinum type E endospores against HPT treatments. These results can be helpful for future safety considerations. This paper was presented at the 8th International Conference on High Pressure Bioscience & Biotechnology (HPBB 2014), in Nantes (France), 15-18 July 2014.

  10. Pre-irradiation induced emulsion co-graft polymerization of acrylonitrile and acrylic acid onto a polyethylene nonwoven fabric

    NASA Astrophysics Data System (ADS)

    Liu, Hanzhou; Yu, Ming; Ma, Hongjuan; Wang, Ziqiang; Li, Linfan; Li, Jingye

    2014-01-01

    A pre-irradiation induced emulsion co-graft polymerization method was used to introduce acrylonitrile and acrylic acid onto a PE nonwoven fabric. The use of acrylic acid is meant to improve the hydrophilicity of the modified fabric. The kinetics of co-graft polymerization were studied. The existence of polyacrylonitrile (PAN) and poly(acrylic acid) (PAAc) graft chains was proven by Fourier transform infrared spectroscopy (FTIR) analysis. The existence of the nitrile groups in the graft chains indicates that they are ready for further amidoximation and adsorption of heavy metal ions.

  11. Double emulsion solvent evaporation techniques used for drug encapsulation.

    PubMed

    Iqbal, Muhammad; Zafar, Nadiah; Fessi, Hatem; Elaissari, Abdelhamid

    2015-12-30

    Double emulsions are complex systems, also called "emulsions of emulsions", in which the droplets of the dispersed phase contain one or more types of smaller dispersed droplets themselves. Double emulsions have the potential for encapsulation of both hydrophobic as well as hydrophilic drugs, cosmetics, foods and other high value products. Techniques based on double emulsions are commonly used for the encapsulation of hydrophilic molecules, which suffer from low encapsulation efficiency because of rapid drug partitioning into the external aqueous phase when using single emulsions. The main issue when using double emulsions is their production in a well-controlled manner, with homogeneous droplet size by optimizing different process variables. In this review special attention has been paid to the application of double emulsion techniques for the encapsulation of various hydrophilic and hydrophobic anticancer drugs, anti-inflammatory drugs, antibiotic drugs, proteins and amino acids and their applications in theranostics. Moreover, the optimized ratio of the different phases and other process parameters of double emulsions are discussed. Finally, the results published regarding various types of solvents, stabilizers and polymers used for the encapsulation of several active substances via double emulsion processes are reported.

  12. Whey protein/polysaccharide-stabilized emulsions: Effect of polymer type and pH on release and topical delivery of salicylic acid.

    PubMed

    Combrinck, Johann; Otto, Anja; du Plessis, Jeanetta

    2014-06-01

    Emulsions are widely used as topical formulations in the pharmaceutical and cosmetic industries. They are thermodynamically unstable and require emulsifiers for stabilization. Studies have indicated that emulsifiers could affect topical delivery of actives, and this study was therefore designed to investigate the effects of different polymers, applied as emulsifiers, as well as the effects of pH on the release and topical delivery of the active. O/w emulsions were prepared by the layer-by-layer technique, with whey protein forming the first layer around the oil droplets, while either chitosan or carrageenan was subsequently adsorbed to the protein at the interface. Additionally, the emulsions were prepared at three different pH values to introduce different charges to the polymers. The active ingredient, salicylic acid, was incorporated into the oil phase of the emulsions. Physical characterization of the resulting formulations, i.e., droplet size, zeta potential, stability, and turbidity in the water phase, was performed. Release studies were conducted, after which skin absorption studies were performed on the five most stable emulsions, by using Franz type diffusion cells and utilizing human, abdominal skin membranes. It was found that an increase in emulsion droplet charge could negatively affect the release of salicylic acid from these formulations. Contrary, positively charged emulsion droplets were found to enhance dermal and transdermal delivery of salicylic acid from emulsions. It was hypothesized that electrostatic complex formation between the emulsifier and salicylic acid could affect its release, whereas electrostatic interaction between the emulsion droplets and skin could influence dermal/transdermal delivery of the active.

  13. A comparative study of the physicochemical properties of a virgin coconut oil emulsion and commercial food supplement emulsions.

    PubMed

    Khor, Yih Phing; Koh, Soo Peng; Long, Kamariah; Long, Shariah; Ahmad, Sharifah Zarah Syed; Tan, Chin Ping

    2014-07-01

    Food manufacturers are interested in developing emulsion-based products into nutritional foods by using beneficial oils, such as fish oil and virgin coconut oil (VCO). In this study, the physicochemical properties of a VCO oil-in-water emulsion was investigated and compared to other commercial oil-in-water emulsion products (C1, C2, C3, and C4). C3 exhibited the smallest droplet size of 3.25 µm. The pH for the emulsion samples ranged from 2.52 to 4.38 and thus were categorised as acidic. In a texture analysis, C2 was described as the most firm, very adhesive and cohesive, as well as having high compressibility properties. From a rheological viewpoint, all the emulsion samples exhibited non-Newtonian behaviour, which manifested as a shear-thinning property. The G'G'' crossover illustrated by the VCO emulsion in the amplitude sweep graph but not the other commercial samples illustrated that the VCO emulsion had a better mouthfeel. In this context, the VCO emulsion yielded the highest zeta potential (64.86 mV), which was attributed to its strong repulsive forces, leading to a good dispersion system. C2 comprised the highest percentage of fat among all emulsion samples, followed by the VCO emulsion, with 18.44% and 6.59%, respectively.

  14. Rejuvenation of Spent Media via Supported Emulsion Liquid Membranes

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.

    2002-01-01

    The overall goal of this project was to maximize the reuseability of spent fermentation media. Supported emulsion liquid membrane separation, a highly efficient extraction technique, was used to remove inhibitory byproducts during fermentation; thus, improve the yield while reducing the need for fresh water. The key objectives of this study were: (1) Develop an emulsion liquid membrane system targeting low molecular weight organic acids which has minimal toxicity on a variety of microbial systems. (2) Conduct mass transfer studies to allow proper modeling and design of a supported emulsion liquid membrane system. (3) Investigate the effect of gravity on emulsion coalescence within the membrane unit. (4) Access the effect of water re-use on fermentation yields in a model microbial system. and (5) Develop a perfusion-type fermentor utilizing a supported emulsion liquid membrane system to control inhibitory fermentation byproducts (not completed due to lack of funds)

  15. A new generation scanning system for the high-speed analysis of nuclear emulsions

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Buonaura, A.; Consiglio, L.; D'Ambrosio, N.; De Lellis, G.; Di Crescenzo, A.; Galati, G.; Lauria, A.; Montesi, M. C.; Tioukov, V.; Vladymyrov, M.

    2016-06-01

    The development of automatic scanning systems was a fundamental issue for large scale neutrino detectors exploiting nuclear emulsions as particle trackers. Such systems speed up significantly the event analysis in emulsion, allowing the feasibility of experiments with unprecedented statistics. In the early 1990s, R&D programs were carried out by Japanese and European laboratories leading to automatic scanning systems more and more efficient. The recent progress in the technology of digital signal processing and of image acquisition allows the fulfillment of new systems with higher performances. In this paper we report the description and the performance of a new generation scanning system able to operate at the record speed of 84 cm2/hour and based on the Large Angle Scanning System for OPERA (LASSO) software infrastructure developed by the Naples scanning group. Such improvement, reduces the scanning time by a factor 4 with respect to the available systems, allowing the readout of huge amount of nuclear emulsions in reasonable time. This opens new perspectives for the employment of such detectors in a wider variety of applications.

  16. Effect of emulsifiers and their liquid crystalline structures in emulsions on dermal and transdermal delivery of hydroquinone, salicylic acid and octadecenedioic acid.

    PubMed

    Otto, A; Wiechers, J W; Kelly, C L; Dederen, J C; Hadgraft, J; du Plessis, J

    2010-01-01

    This study investigated the effect of emulsifiers and their liquid crystalline structures on the dermal and transdermal delivery of hydroquinone (HQ), salicylic acid (SA) and octadecenedioic acid (DIOIC). Emulsions containing liquid crystalline phases were compared with an emulsion without liquid crystals. Skin permeation experiments were performed using Franz-type diffusion cells and human abdominal skin dermatomed to a thickness of 400 mum. The results indicate that emulsifiers arranging in liquid crystalline structures in the water phase of the emulsion enhanced the skin penetration of the active ingredients with the exception of SA. SA showed a different pattern of percutaneous absorption, and no difference in dermal and transdermal delivery was observed between the emulsions with and without liquid crystalline phases. The increase in skin penetration of HQ and DIOIC could be attributed to an increased partitioning of the actives into the skin. It was hypothesized that the interaction between the different emulsifiers and active ingredients in the formulations varied and, therefore, the solubilization capacities of the various emulsifiers and their association structures.

  17. Stabilization of emulsion and butter like products containing essential fatty acids using kalonji seeds extract and curcuminoids.

    PubMed

    Rege, Sameera A; Momin, Shamim A; Bhowmick, Dipti N; Pratap, Amit A

    2012-01-01

    Owing to the tendency of essential fatty acids (EFAs) to undergo autoxidation, their storage becomes a key problem. Generally, they are stabilized by synthetic antioxidants like TBHQ that are toxic in nature. Recently many studies were reported where these EFAs are stabilized by natural antioxidants. In the present study, curcuminoids and kalonji seeds ethanol extract (KEE) were used to stabilize these EFAs in refined sunflower oil (RSFO), water-in-oil (w/o) emulsion and butter like products (BLPs). In RSFO, though curcuminoids alone exerted pro-oxidant effect, KEE and curcuminoids showed synergistic antioxidant activity that was comparable to TBHQ. KEE exhibited good antioxidant activity in emulsions and BLPs, providing fine physical properties like slipping point, dropping point and spreadability. EFAs increased the nutritional value of BLPs and antioxidants added for their stabilization provided their medicinal benefits.

  18. Recycling nanoparticle catalysts without separation based on a pickering emulsion/organic biphasic system.

    PubMed

    Liu, Huifang; Zhang, Zhiming; Yang, Hengquan; Cheng, Fangqin; Du, Zhiping

    2014-07-01

    A conceptually novel methodology is explored for in situ recycling of nanoparticle catalysts based on transforming a conventional organic/aqueous biphasic system into a Pickering emulsion/organic biphasic system (PEOBS). The suggested PEOBS exists as two phases, with the nanoparticle catalyst "anchored" in the Pickering emulsion phase, but is "continuous" between the organic phase and the continuous phase of the Pickering emulsion. Aqueous hydrogenations are used to evaluate the reaction performances of PEOBS, and the underlying principles of PEOBS are preliminarily elaborated. The unique properties of PEOBS lead to many intriguing findings, which are unlikely to be achieved in the reported biphasic systems. PEOBS exhibits more than a fourfold enhancement in catalysis efficiency in comparison with a conventional biphasic system. Impressively, PEOBS enables the organic product to be facilely isolated through simple decantation and the nanoparticle catalyst can be recycled in situ without the need for "separation". Its recycling effectiveness is justified by ten reaction cycles without significant catalyst loss. The simple protocol, in conjunction with the stability to simultaneously achieve high catalysis efficiency and excellent catalyst recyclability, makes PEOBS a promising methodology to develop more sustainable nanocatalysis.

  19. Optimization for Reduced-Fat / Low-NaCl Meat Emulsion Systems with Sea Mustard (Undaria pinnatifida) and Phosphate.

    PubMed

    Kim, Cheon-Jei; Hwang, Ko-Eun; Song, Dong-Heon; Jeong, Tae-Jun; Kim, Hyun-Wook; Kim, Young-Boong; Jeon, Ki-Hong; Choi, Yun-Sang

    2015-01-01

    The effects of reducing fat levels from 30% to 20% and salt concentrations from 1.5% to 1.0% by partially substituting incorporated phosphate and sea mustard were investigated based on physicochemical properties of reduced-fat / low-NaCl meat emulsion systems. Cooking loss and emulsion stability, hardness, springiness, and cohesiveness for reduced-fat / low-NaCl meat emulsion systems with 20% pork back fat and 1.2% sodium chloride samples with incorporation of phosphate and sea mustard were similar to the control with 30% pork back fat and 1.5% sodium chloride. Results showed that reduced-fat / low-NaCl meat emulsion system samples containing phosphate and sea mustard had higher apparent viscosity. The results of this study show that the incorporation of phosphate and sea mustard in the formulation will successfully reduce fat and salt in the final meat products.

  20. Optimization for Reduced-Fat / Low-NaCl Meat Emulsion Systems with Sea Mustard (Undaria pinnatifida) and Phosphate

    PubMed Central

    Kim, Cheon-Jei; Hwang, Ko-Eun; Song, Dong-Heon; Jeong, Tae-Jun; Kim, Hyun-Wook

    2015-01-01

    The effects of reducing fat levels from 30% to 20% and salt concentrations from 1.5% to 1.0% by partially substituting incorporated phosphate and sea mustard were investigated based on physicochemical properties of reduced-fat / low-NaCl meat emulsion systems. Cooking loss and emulsion stability, hardness, springiness, and cohesiveness for reduced-fat / low-NaCl meat emulsion systems with 20% pork back fat and 1.2% sodium chloride samples with incorporation of phosphate and sea mustard were similar to the control with 30% pork back fat and 1.5% sodium chloride. Results showed that reduced-fat / low-NaCl meat emulsion system samples containing phosphate and sea mustard had higher apparent viscosity. The results of this study show that the incorporation of phosphate and sea mustard in the formulation will successfully reduce fat and salt in the final meat products. PMID:26761874

  1. Review of in vitro digestion models for rapid screening of emulsion-based systems.

    PubMed

    McClements, David Julian; Li, Yan

    2010-10-01

    There is increasing interest in understanding and controlling the digestion of emulsified lipids within the food and pharmaceutical industries. Emulsion-based delivery systems are being developed to encapsulate, protect, and release non-polar lipids, vitamins, nutraceuticals, and drugs. These delivery systems are also being used to control the stability and digestion of lipids within the human gastrointestinal tract so as to create foods that enhance satiety and reduce hunger. In vitro digestion models are therefore needed to test the efficacy of different approaches of controlling lipid digestion under conditions that simulate the human gastrointestinal tract. This article reviews the current status of in vitro digestion models for simulating lipid digestion, with special emphasis on the pH stat method. The pH stat method is particularly useful for the rapid screening of food emulsions and emulsion-based delivery systems with different compositions and structures. Successful candidates can then be tested with more rigorous in vitro digestion models, or using animal or human feeding studies.

  2. One-step formation of multiple Pickering emulsions stabilized by self-assembled poly(dodecyl acrylate-co-acrylic acid) nanoparticles.

    PubMed

    Zhu, Ye; Sun, Jianhua; Yi, Chenglin; Wei, Wei; Liu, Xiaoya

    2016-09-13

    In this study, a one-step generation of stable multiple Pickering emulsions using pH-responsive polymeric nanoparticles as the only emulsifier was reported. The polymeric nanoparticles were self-assembled from an amphiphilic random copolymer poly(dodecyl acrylate-co-acrylic acid) (PDAA), and the effect of the copolymer content on the size and morphology of PDAA nanoparticles was determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The emulsification study of PDAA nanoparticles revealed that multiple Pickering emulsions could be generated through a one-step phase inversion process by using PDAA nanoparticles as the stabilizer. Moreover, the emulsification performance of PDAA nanoparticles at different pH values demonstrated that multiple emulsions with long-time stability could only be stabilized by PDAA nanoparticles at pH 5.5, indicating that the surface wettability of PDAA nanoparticles plays a crucial role in determining the type and stability of the prepared Pickering emulsions. Additionally, the polarity of oil does not affect the emulsification performance of PDAA nanoparticles, and a wide range of oils could be used as the oil phase to prepare multiple emulsions. These results demonstrated that multiple Pickering emulsions could be generated via the one-step emulsification process using self-assembled polymeric nanoparticles as the stabilizer, and the prepared multiple emulsions have promising potential to be applied in the cosmetic, medical, and food industries.

  3. Synthesis and Characterization of Waterborne Fluoropolymers Prepared by the One-Step Semi-Continuous Emulsion Polymerization of Chlorotrifluoroethylene, Vinyl Acetate, Butyl Acrylate, Veova 10 and Acrylic Acid.

    PubMed

    Liu, Hongzhu; Bian, Jiming; Wang, Zhonggang; Hou, Chuan-Jin

    2017-01-22

    Waterborne fluoropolymer emulsions were synthesized using the one-step semi-continuous seed emulsion polymerization of chlorotrifluoroethylene (CTFE), vinyl acetate (VAc), n-butyl acrylate (BA), Veova 10, and acrylic acid (AA). The main physical parameters of the polymer emulsions were tested and analyzed. Characteristics of the polymer films such as thermal stability, glass transition temperature, film-forming properties, and IR spectrum were studied. Meanwhile, the weatherability of fluoride coatings formulated by the waterborne fluoropolymer and other coatings were evaluated by the quick ultraviolet (QUV) accelerated weathering test, and the results showed that the fluoropolymer with more than 12% fluoride content possessed outstanding weather resistance. Moreover, scale-up and industrial-scale experiments of waterborne fluoropolymer emulsions were also performed and investigated.

  4. Effects of an omega-3 fatty acid-enriched lipid emulsion on eicosanoid synthesis in acute respiratory distress syndrome (ARDS): A prospective, randomized, double-blind, parallel group study

    PubMed Central

    2011-01-01

    Background The use of lipid emulsions has been associated with changes in lung function and gas exchange which may be mediated by biologically active metabolites derived from arachidonic acid. The type and quantity of the lipid emulsions used could modulate this response, which is mediated by the eicosanoids. This study investigates the use of omega-3 fatty acid-enriched lipid emulsions in ARDS patients and their effects on eicosanoid values. Methods Prospective, randomized, double-blind, parallel group study carried out at the Intensive Medicine Department of Vall d'Hebron University Hospital (Barcelona-Spain). We studied 16 consecutive patients with ARDS and intolerance to enteral nutrition (14 men; age: 58 ± 13 years; APACHE II score 17.8 ± 2.3; Lung Injury Score: 3.1 ± 0.5; baseline PaO2/FiO2 ratio: 149 ± 40). Patients were randomized into two groups: Group A (n = 8) received the study emulsion Lipoplus® 20%, B. Braun Medical (50% MCT, 40% LCT, 10% fish oil (FO)); Group B (n = 8) received the control emulsion Intralipid® Fresenius Kabi (100% LCT). Lipid emulsions were administered for 12 h at a dose of 0.12 g/kg/h. We measured LTB4, TXB2, and 6-keto prostaglandin F1α values at baseline [immediately before the administration of the lipid emulsions (T-0)], at the end of the administration (T-12) and 24 hours after the beginning of the infusion (T 24) in arterial and mixed venous blood samples. Results In group A (FO) LTB4, TXB2, 6-keto prostaglandin F1α levels fell during omega-3 administration (T12). After discontinuation (T24), levels of inflammatory markers (both systemic and pulmonary) behaved erratically. In group B (LCT) all systemic and pulmonary mediators increased during lipid administration and returned to baseline levels after discontinuation, but the differences did not reach statistical significance. There was a clear interaction between the treatment in group A (fish oil) and changes in LTB4 over time. Conclusions Infusion of lipids enriched

  5. Functionalities of chitosan conjugated with stearic acid and gallic acid and application of the modified chitosan in stabilizing labile aroma compounds in an oil-in-water emulsion.

    PubMed

    Yang, Tsung-Shi; Liu, Tai-Ti; Lin, I-Hwa

    2017-08-01

    The aims of this research were to conjugate chitosan (CT) with stearic acid (SA) and gallic acid (GA), and apply the modified chitosan to stabilize labile aroma compounds such as allyl isothiocyanate (AITC) and limonene in oil-in-water emulsions. Generally, the antioxidant activity of CT-SA-GA increased as the GA content in the conjugate increased. In most assays, GA had a lower IC50 value than that of CT-SA-GA; however, CT-SA-GA exhibited better performance than GA in the Fe(2+)-chelating activity. In accelerated tests (heating or illumination) for evaluating the chemical stability of AITC and limonene during storage, CT-SA and CT-SA-GA were used to prepare AITC and limonene O/W emulsions, respectively. Tween 80 and Span 80 (T-S-80), an emulsifier mixture, were used as a control in both emulsions for comparison. The results show that CT-SA or CT-SA-GA could protect AITC or limonene from degradation or oxidation more effectively than T-S-80.

  6. Influences of fatty acid moiety and esterification of polyglycerol fatty acid esters on the crystallization of palm mid fraction in oil-in-water emulsion.

    PubMed

    Sakamoto, Mitsuhiro; Ohba, Azusa; Kuriyama, Juhei; Maruo, Kouichi; Ueno, Satoru; Sato, Kiyotaka

    2004-08-15

    We examined the crystallization of palm mid fraction (PMF) in oil-in-water (O/W) emulsion, after adding polyglycerol fatty acid esters (PGFEs). We employed ultrasonic velocity measurements and DSC techniques, with special emphases on the influences of fatty acid moiety and esterification of PGFE. Twelve types of PGFEs were examined as additives. PGFEs have a large hydrophilic moiety composed of 10 glycerol molecules to which palmitic, stearic and behenic acids were esterified as the fatty acid moiety with different degrees of esterification. Crystallization temperature (T(c)) of PMF remarkably increased with increasing concentrations of the PGFEs as the chain length of the fatty acid moiety increased, and the PGFE became more hydrophobic in accordance with increasing degree of esterification. We observed that the heterogeneous nucleation of PMF in the O/W emulsion was activated at the oil-water interface, where the template effect of very hydrophobic long saturated fatty acid chains of the PGFE might play the main role of heterogeneous nucleation.

  7. The influence of alkali fatty acids on the properties and the stability of parenteral O/W emulsions modified with solutol HS 15.

    PubMed

    Buszello, K; Harnisch, S; Müller, R H; Müller, B W

    2000-03-01

    Arachis oil based parenteral O/W emulsions were prepared using soya bean phosphatidylcholine (SPC) and different combinations of co-emulsifiers containing polyethylene glycol fatty acid esters (Solutol HS 15) and alkali fatty acids (sodium laurate, sodium stearate). The parameters measured were droplet size (both by photon correlation spectroscopy and laser diffractometry), pH and zeta potential. All emulsions were subjected to autoclaving. The addition of polyethylene glycol 12-hydroxy stearate (Solutol HS 15) led to a significant decrease of mean oil droplet size. For long-term stability the amount added turned out to be the most important factor. With increased amounts of Solutol HS 15 the packing density of the emulsifier layer and the zeta potential decreased leading to instability. The optimum load of Solutol HS 15 was found to be 15 micromol/ml. Alkali fatty acids markedly improved the physical stability of the emulsions. Improved stability properties conferred to emulsions by alkali fatty acids could be attributed to the zeta potential increase even in the presence of Solutol HS 15. Consequently a mixed emulsifier film was established in which the ionized fatty acids determined the interface charge. In addition to this a strengthening of the molecular interactions occurring between phospholipid and Solutol HS 15 emulsifier in the presence of ionized fatty acids at the O/W interface can be assumed (L. Rydhag, The importance of the phase behaviour of phospholipids for emulsion stability, Fette Seifen Anstrichm. 81 (1979) 168-173). Different co-emulsifier mixtures were shown to have a pronounced impact on the plasma protein adsorption onto emulsion droplets.

  8. Phase behavior, formation, and rheology of cubic phase and related gel emulsion in Tween 80/water/oil systems.

    PubMed

    Alam, Mohammad Mydul; Ushiyama, Kousuke; Aramaki, Kenji

    2009-01-01

    We investigated the phase behavior, formation, and rheology of the cubic phase (I(1)) and related O/I(1) gel emulsion in water/Tween 80/oil systems using squalane, liquid paraffin (LP), and decane as oil components. In the phase behavior study, the phase sequences were similar for squalane and LP systems, while a lamellar liquid crystal (L(alpha)) was observed for decane system. In all the systems the addition of oil to W(m) or H(1) phase induced the I(1) phase, which can solubilize some amounts of oil followed by the appearance of I(1)+O phase. The formation of the O/I(1) gel emulsion has been studied at a fixed w/s (50/50) and we found that 30 wt% decane, 70 wt% squalane, and 60 wt% LP can form the gel emulsion. The water/Tween 80/squalane system has been taken as a model system to study viscoelastic properties of the I(1) phase and O/I(1) gel emulsion. The I(1) phase shows a typical hard gel cubic structure under the frequency and the values of the complex viscosity, /eta*/ and the elastic modulus, G ' increase with the addition of squalane, which could be due to the neighboring micellar interaction. On the other hand, the decreasing values of the viscoelastic parameters in the O/I(1) gel emulsion simply relate to the volume fraction of the I(1) phase in the system.

  9. An Emulsion Paste System for Decontamination of Vesicants

    DTIC Science & Technology

    1945-02-07

    1.7 5, neg. neg. - "" 1.1 2. 2 14 , 28 neg. "" 0.8 ’i4 ncg. K Oleate /S-461 0.9 n- efg."It 0.6 2 - nog. "I i 1.2 il - ncg. 2. A series of experiments...NDRC potassium oleate paste was examined and both paste systems com- pared to TCE/RH-195 solution. TCE/RH-195 was found to be the most efficient and...tetrachlorocthylcnc) potassium oleate and S-L61 or S-210, has some advantages over the TCE/RH-195 system. This Perclene/potassium oleate /chloroamide paste was

  10. A novel retinoic acid, catechin hydrate and mustard oil-based emulsion for enhanced cytokine and antibody responses against multiple strains of HIV-1 following mucosal and systemic vaccinations

    PubMed Central

    Yu, Mingke; Vajdy, Michael

    2011-01-01

    Non-replicating protein- or DNA-based antigens generally require immune-enhancing adjuvants and delivery systems. It has been particularly difficult to raise antibodies against gp120 of HIV-1, which constitutes an important approach in HIV vaccine design. While almost all effort in adjuvant research has focused on mimicking the pathogens and the danger signals they engender in the host, relatively little effort has been spent on nutritive approaches. In this study, a new nutritive immune-enhancing delivery system (NIDS) composed of vitamin A, a polyphenol-flavonoid catechin hydrate, and mustard oil was tested for its adjuvant effect in immune responses against the gp120 protein of HIV-1CN54. Following a combination of two mucosal and two systemic vaccinations of mice, we found significant enhancement of both local and systemic antibodies as well as cytokine responses. These data have important implications for vaccine and adjuvant design against HIV-1 and other pathogens. PMID:21272602

  11. Stable concentrated emulsions of the 1-monoglyceride of capric acid (monocaprin) with microbicidal activities against the food-borne bacteria Campylobacter jejuni, Salmonella spp., and Escherichia coli.

    PubMed

    Thormar, Halldor; Hilmarsson, Hilmar; Bergsson, Gudmundur

    2006-01-01

    Of 11 fatty acids and monoglycerides tested against Campylobacter jejuni, the 1-monoglyceride of capric acid (monocaprin) was the most active in killing the bacterium. Various monocaprin-in-water emulsions were prepared which were stable after storage at room temperature for many months and which retained their microbicidal activity. A procedure was developed to manufacture up to 500 ml of 200 mM preconcentrated emulsions of monocaprin in tap water. The concentrates were clear and remained stable for at least 12 months. They were active against C. jejuni upon 160- to 200-fold dilution in tap water and caused a >6- to 7-log(10) reduction in viable bacterial count in 1 min at room temperature. The addition of 0.8% Tween 40 to the concentrates as an emulsifying agent did not change the microbicidal activity. Emulsions of monocaprin killed a variety of Campylobacter isolates from humans and poultry and also killed strains of Campylobacter coli and Campylobacter lari, indicating a broad anticampylobacter activity. Emulsions of 1.25 mM monocaprin in citrate-lactate buffer at pH 4 to 5 caused a >6- to 7-log(10) reduction in viable bacterial counts of Salmonella spp. and Escherichia coli in 10 min. C. jejuni was also more susceptible to monocaprin emulsions at low pH. The addition of 5 and 10 mM monocaprin emulsions to Campylobacter-spiked chicken feed significantly reduced the bacterial contamination. These results are discussed in view of the possible utilization of monocaprin emulsions in controlling the spread of food-borne bacteria from poultry to humans.

  12. Design Space Approach for Preservative System Optimization of an Anti-Aging Eye Fluid Emulsion.

    PubMed

    Lourenço, Felipe Rebello; Francisco, Fabiane Lacerda; Ferreira, Márcia Regina Spuri; Andreoli, Terezinha De Jesus; Löbenberg, Raimar; Bou-Chacra, Nádia

    2015-01-01

    The use of preservatives must be optimized in order to ensure the efficacy of an antimicrobial system as well as the product safety. Despite the wide variety of preservatives, the synergistic or antagonistic effects of their combinations are not well established and it is still an issue in the development of pharmaceutical and cosmetic products. The purpose of this paper was to establish a space design using a simplex-centroid approach to achieve the lowest effective concentration of 3 preservatives (methylparaben, propylparaben, and imidazolidinyl urea) and EDTA for an emulsion cosmetic product. Twenty-two formulae of emulsion differing only by imidazolidinyl urea (A: 0.00 to 0.30% w/w), methylparaben (B: 0.00 to 0.20% w/w), propylparaben (C: 0.00 to 0.10% w/w) and EDTA (D: 0.00 to 0.10% w/w) concentrations were prepared. They were tested alone and in binary, ternary and quaternary combinations. Aliquots of these formulae were inoculated with several microorganisms. An electrochemical method was used to determine microbial burden immediately after inoculation and after 2, 4, 8, 12, 24, 48, and 168 h. An optimization strategy was used to obtain the concentrations of preservatives and EDTA resulting in a most effective preservative system of all microorganisms simultaneously. The use of preservatives and EDTA in combination has the advantage of exhibiting a potential synergistic effect against a wider spectrum of microorganisms. Based on graphic and optimization strategies, we proposed a new formula containing a quaternary combination (A: 55%; B: 30%; C: 5% and D: 10% w/w), which complies with the specification of a conventional challenge test. A design space approach was successfully employed in the optimization of concentrations of preservatives and EDTA in an emulsion cosmetic product.

  13. In vitro digestion of fish oils rich in n-3 polyunsaturated fatty acids studied in emulsion and at the oil-water interface.

    PubMed

    Marze, Sébastien; Meynier, Anne; Anton, Marc

    2013-02-01

    The in vitro digestion of β-lactoglobulin stabilized emulsions rich in the n-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), was studied using several physicochemical techniques. Artificial media for the mouth, stomach and small intestine were used in a sequential static in vitro digestion method. Different sizing techniques were compared to follow the droplet size during the digestion steps, including diffusing wave spectroscopy (DWS) which allowed direct measurements on undiluted emulsions. Titration of fatty acids confirmed that the digestion of such emulsified fish oils is partial. The study of the digestion at the oil-water interface using tensiometry revealed specific affinities between lipids and proteins. These could explain the emulsion and the single droplet lipolysis. Nevertheless, by comparing our results to a previous study on fish oil lipolysis, we identified two other important factors. Those were the aqueous solubility and the rate of hydrolysis of the individual fatty acids, the emulsion with the most soluble and hydrolysable ones being digested more quickly.

  14. Data on the physical characterization of oil in water emulsions.

    PubMed

    Zalazar, Aldana L; Gliemmo, María F; Campos, Carmen A

    2016-12-01

    This article contains experimental data and images for the physical characterization of oil in water emulsions. Mentioned data are related to the research article "Effect of stabilizers, oil level and structure on the growth of Zygosaccharomyces bailii and on physical stability of model systems simulating acid sauces" (A.L. Zalazar, M.F. Gliemmo, C.A. Campos, 2016) [1]. Physical characterization of emulsions was performed through the evaluation of Span and Specific Surface Area (SSA) determined by light scattering using a Mastersizer. Furthermore, microscopy images were recorded by confocal scanning laser microscopy (CSLM). The latter are presented to collaborate in the analysis of emulsion microstructure.

  15. Dynamics of controlled release systems based on water-in-water emulsions: a general theory.

    PubMed

    Sagis, Leonard M C

    2008-10-06

    Phase-separated biopolymer solutions, and aqueous dispersions of hydrogel beads, liposomes, polymersomes, aqueous polymer microcapsules, and colloidosomes are all examples of water-in-water emulsions. These systems can be used for encapsulation and controlled release purposes, in for example food or pharmaceutical applications. The stress-deformation behavior of the droplets in these systems is very complex, and affected by mass transfer across the interface. The relaxation time of a deformation of a droplet may depend on interfacial properties such as surface tension, bending rigidity, spontaneous curvature, permeability, and interfacial viscoelasticity. It also depends on bulk viscoelasticity and composition. A non-equilibrium thermodynamic model is developed for the dynamic behavior of these systems, which incorporates all these parameters, and is based on the interfacial transport phenomena (ITP) formalism. The ITP formalism allows us to describe all water-in-water emulsions with one general theory. Phase-separated biopolymer solutions, and dispersions of hydrogel beads, liposomes, polymersomes, polymer microcapsules, and colloidosomes are basically limiting cases of this general theory with respect to bulk and interfacial rheological behavior.

  16. Differential molecular regulation of bile acid homeostasis by soy lipid induced phytosterolemia and fish oil lipid emulsions in TPN-fed preterm pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prolonged total parenteral nutrition (PN) may lead to cholestasis and liver disease (PNALD). The soybean oil-based lipid emulsion (Intralipid) and its constituent phytosterols have been implicated in PNALD. Phytosterols may induce cholestasis by antagonism of the nuclear bile-acid receptor, FXR, lea...

  17. Fabrication of Silica Nanospheres Coated Membranes: towards the Effective Separation of Oil-in-Water Emulsion in Extremely Acidic and Concentrated Salty Environments

    PubMed Central

    Chen, Yuning; Liu, Na; Cao, Yingze; Lin, Xin; Xu, Liangxin; Zhang, Weifeng; Wei, Yen; Feng, Lin

    2016-01-01

    A superhydrophilic and underwater superoleophobic surface is fabricated by simply coating silica nanospheres onto a glass fiber membrane through a sol-gel process. Such membrane has a complex framework with micro and nano structures covering and presents a high efficiency (more than 98%) of oil-in-water emulsion separation under harsh environments including strong acidic and concentrated salty conditions. This membrane also possesses outstanding stability since no obvious decline in efficiency is observed after different kinds of oil-in-water emulsions separation, which provides it candidate for comprehensive applicability. PMID:27597570

  18. Fabrication of Silica Nanospheres Coated Membranes: towards the Effective Separation of Oil-in-Water Emulsion in Extremely Acidic and Concentrated Salty Environments

    NASA Astrophysics Data System (ADS)

    Chen, Yuning; Liu, Na; Cao, Yingze; Lin, Xin; Xu, Liangxin; Zhang, Weifeng; Wei, Yen; Feng, Lin

    2016-09-01

    A superhydrophilic and underwater superoleophobic surface is fabricated by simply coating silica nanospheres onto a glass fiber membrane through a sol-gel process. Such membrane has a complex framework with micro and nano structures covering and presents a high efficiency (more than 98%) of oil-in-water emulsion separation under harsh environments including strong acidic and concentrated salty conditions. This membrane also possesses outstanding stability since no obvious decline in efficiency is observed after different kinds of oil-in-water emulsions separation, which provides it candidate for comprehensive applicability.

  19. Physical and oxidative stability of fish oil-in-water emulsions stabilized with beta-lactoglobulin and pectin.

    PubMed

    Katsuda, Marly S; McClements, D J; Miglioranza, Lucia H S; Decker, Eric A

    2008-07-23

    The oxidation of fatty acids can be inhibited by engineering the surface of oil-in-water emulsion droplets to decrease interactions between aqueous phase prooxidants and lipids. The objective of this research was to evaluate whether emulsions stabilized by a multilayer emulsifier systems consisting of beta-lactoglobulin and citrus or sugar beet pectin could produce fish oil-in-water emulsions that had good physical and oxidative stability. Sugar beet pectin was compared to citrus pectin because the sugar beet pectin contains the known antioxidant, ferulic acid. A primary Menhaden oil-in-water emulsion was prepared with beta-lactoglobulin upon which the pectins were electrostatically deposited at pH 3.5. Emulsions prepared with 1% oil, 0.05% beta-lactoglobulin, and 0.06% pectins were physically stable for up to 16 days. As determined by monitoring lipid hydroperoxide and headspace propanal formation, emulsions prepared with the multilayer system of beta-lactoglobulin and citrus pectin were more stable than emulsions stabilized with beta-lactoglobulin alone. Emulsions prepared with the multilayer system of beta-lactoglobulin and sugar beet pectin were less stable than emulsions stabilized with beta-lactoglobulin alone despite the presence of ferulic acid in the sugar beet pectin. The lower oxidative stability of the emulsions with the sugar beet pectin could be due to its higher iron and copper concentrations which would produce oxidative stress that would overcome the antioxidant capacity of ferulic acid. These data suggest that the oxidative stability of oil-in-water emulsions containing omega-3 fatty acids could be improved by the use of multilayer emulsion systems containing pectins with low metal concentrations.

  20. Physicochemical characterisation of β-carotene emulsion stabilised by covalent complexes of α-lactalbumin with (-)-epigallocatechin gallate or chlorogenic acid.

    PubMed

    Wang, Xiaoya; Liu, Fuguo; Liu, Lei; Wei, Zihao; Yuan, Fang; Gao, Yanxiang

    2015-04-15

    In this study the impact of covalent complexes of α-lactalbumin (α-La) with (-)-epigallocatechin gallate (EGCG) or chlorogenic acid (CA) was investigated on the physicochemical properties of β-carotene oil-in-water emulsions. EGCG, or CA, was covalently linked to α-La at pH 8.0, as evidenced by increased total phenolic content and declined fluorescence intensity. Compared with those stabilised by α-La alone and α-La-CA or EGCG mixture, the emulsion stabilised by the α-La-EGCG covalent complex exhibited the least changes in particle size and transmission profiles, using a novel centrifugal sedimentation technique, indicating an improvement in the physical stability. The least degradation of β-carotene occurred in the emulsion stabilised with the α-La-EGCG covalent complex when stored at 25 °C. These results implied that protein-polyphenol covalent complexes were able to enhance the physical stability of β-carotene emulsion and inhibit the degradation of β-carotene in oil-in-water emulsion, and the effect was influenced by the types of the phenolic compounds.

  1. A new scanning system for alpha decay events as calibration sources for range-energy relation in nuclear emulsion

    NASA Astrophysics Data System (ADS)

    Yoshida, J.; Kinbara, S.; Mishina, A.; Nakazawa, K.; Soe, M. K.; Theint, A. M. M.; Tint, K. T.

    2017-03-01

    A new scanning system named "Vertex picker" has been developed to rapid collect alpha decay events, which are calibration sources for the range-energy relation in nuclear emulsion. A computer-controlled optical microscope scans emulsion layers exhaustively, and a high-speed and high-resolution camera takes their micrographs. A dedicated image processing picks out vertex-like shapes. Practical operations of alpha decay search were demonstrated by emulsion sheets of the KEK-PS E373 experiment. Alpha decays of nearly 28 events were detected in eye-check work on a PC monitor per hour. This yield is nearly 20 times more effective than that by the conventional eye-scan method. The speed and quality is acceptable for the coming new experiment, J-PARC E07.

  2. Changes in two-phase emulsion morphology in temperature-amphiphile concentration or fish diagram for ternary amphiphile/oil/water systems.

    PubMed

    Lee, Jong-Moon; Lim, Kyung-Hee

    2005-10-01

    We examined the morphologies of two-phase emulsions in the ternary 2-butoxyethanol/n-decane/water system at various temperatures and water-to-oil ratios (WORs). The two-phase emulsion morphologies depended on temperature, WOR, and amphiphile concentration, and the results are presented in a temperature-amphiphile concentration coordinate system or a "fish" diagram. The observations made in this work contradict the predictions by the phase-inversion-temperature (PIT) concept. At WOR<1, a vertical inversion line was observed at Temulsions. At T>T(uc) (upper critical endpoint temperature) and at low amphiphile concentrations, only B/T emulsions appeared, irrespective of temperature. At WOR>1, the situation was reversed; T/B emulsions at Temulsions at T>T(uc), and T/B emulsions at low amphiphile concentrations, irrespective of temperature. At WOR=1, two horizontal inversion lines, one each at TT(uc), were observed. The morphologies of the two-phase emulsions were B/T or T/B emulsions at low amphiphile concentrations, and at higher amphiphile concentrations T/B at TT(uc). All these findings along with three-phase emulsion data result in complete emulsion morphology diagrams in the temperature-amphiphile concentration space or fish diagram.

  3. A modified emulsion gelation technique to improve buoyancy of hydrogel tablets for floating drug delivery systems.

    PubMed

    Yom-Tov, Ortal; Seliktar, Dror; Bianco-Peled, Havazelet

    2015-10-01

    The use of buoyant or floating hydrogel tablets is of particular interest in the sustained release of drugs to the stomach. They have an ability to slow the release rates of drugs by prolonging their absorption window in the upper part of the gastrointestinal (GI) tract. In this study we synthesized bioactive hydrogels that have sustainable release rates for drugs in the stomach based on a hydrogel preparation technique that employs emulsifying surfactants. The emulsion gelation technique, which encapsulates oil droplets within the hydrogels during crosslinking, was used to decrease their specific gravity in aqueous environments, resulting in floating drug release depots. Properties such as swelling, buoyancy, density and drug release were manipulated by changing the polymer concentrations, surfactant percentages and the oil:polymer ratios. The relationship between these properties and the hydrogel's floating lag time was documented. The potential for this material to be used as a floating drug delivery system was demonstrated.

  4. Semi-solid Sucrose Stearate-Based Emulsions as Dermal Drug Delivery Systems

    PubMed Central

    Klang, Victoria; Schwarz, Julia C.; Matsko, Nadejda; Rezvani, Elham; El-Hagin, Nivine; Wirth, Michael; Valenta, Claudia

    2011-01-01

    Mild non-ionic sucrose ester surfactants can be employed to produce lipid-based drug delivery systems for dermal application. Moreover, sucrose esters of intermediate lipophilicity such as sucrose stearate S-970 possess a peculiar rheological behavior which can be employed to create highly viscous semi-solid formulations without any further additives. Interestingly, it was possible to develop both viscous macroemulsions and fluid nanoemulsions with the same chemical composition merely by slight alteration of the production process. Optical light microscopy and cryo transmission electron microscopy (TEM) revealed that the sucrose ester led to the formation of an astonishing hydrophilic network at a concentration of only 5% w/w in the macroemulsion system. A small number of more finely structured aggregates composed of surplus surfactant were likewise detected in the nanoemulsions. These discoveries offer interesting possibilities to adapt the low viscosity of fluid O/W nanoemulsions for a more convenient application. Moreover, a simple and rapid production method for skin-friendly creamy O/W emulsions with excellent visual long-term stability is presented. It could be shown by franz-cell diffusion studies and in vitro tape stripping that the microviscosity within the semi-solid formulations was apparently not influenced by their increased macroviscosity: the release of three model drugs was not impaired by the complex network-like internal structure of the macroemulsions. These results indicate that the developed semi-solid emulsions with advantageous application properties are highly suitable for the unhindered delivery of lipophilic drugs despite their comparatively large particle size and high viscosity. PMID:24310496

  5. Vitamin A palmitate and α-lipoic acid stability in o/w emulsions for cosmetic application.

    PubMed

    Moyano, M A; Segall, A

    2011-01-01

    Skin becomes thin, dry, pale, and finely wrinkled with age. Retinoids are a large class of compounds that are important in modern therapy for dermatological treatment of wrinkled skin. Of the retinoids, retinol and vitamin A palmitate are thought to induce thickening of the epidermis and to be effective for treatment of skin diseases. Accordingly, α-lipoic acid or the reduced form, dihydrolipoate, are potent scavengers of hydroxyl radicals, superoxide radicals, peroxyl radicals, singlet oxygen, and nitric oxide with anti-inflammatory properties (1). Cosmetic ingredient stability prediction relies on kinetic quantitative chemical analysis of active components at different temperatures. Vitamin A palmitate and α-lipoic acid, are known to be unstable to light or heat (2). The aims of this study were to evaluate the stability of α-lipoic acid and vitamin A palmitate in the presence of vitamin E (acetate) and other antioxidants in lipophilic/hydrophilic medium (O/W emulsions) at pH 3.0, 5.0, and 7.0. The formulations that were investigated contained 0.12% (w/w) vitamin A palmitate, 0.4% (w/w) vitamin E acetate, and 0.5 % α-lipoic acid (formulation A), supplemented with ascorbyl palmitate, magnesium ascorbyl phosphate, and vitamin C (formulation B) or with butylhydroxytoluene (BHT, formulation C) or ascorbyl palmitate (formulation D). The chemical analyses of α-lipoic acid and vitamin A palmitate were carried out by HPLC. Formulations C and D at pH 7.0 were selected as the most stable for these components. The purpose of this paper is the selection of the most stable formulations for their application in in vivo studies.

  6. Automatic track following system to study double strangeness nuclei in nuclear emulsion exposed to the observable limit

    NASA Astrophysics Data System (ADS)

    Myint Kyaw Soe; Goto, Ryosuke; Mishina, Akihiro; Nakanisi, Yoshiaki; Nakashima, Daisuke; Yoshida, Junya; Nakazawa, Kazuma

    2017-03-01

    An automatic track following system has been successfully developed to follow tracks in nuclear emulsion sheets exposed with beam up to the limit to be observed for the first time. The track followed rate of the system is 99.5% with the assistance of the new techniques. The working speed for a track is less than 1 min through one thick emulsion sheet, whereas it is 15 times faster than that of semiautomatic system with human. The system working for 24 h is applied for the E07 experiment at J-PARC and makes it possible to detect 102 nuclei with double strangeness (S=-2 nuclei) within one year. Regarding analyses to identify nuclear species of S=-2 nuclei, the system shows quite decent job for significant steps such as following tracks emitted to spherical directions from S=-2 nuclei, measurement of lengths of followed tracks, and so on.

  7. Lutein-enriched emulsion-based delivery systems: Influence of pH and temperature on physical and chemical stability.

    PubMed

    Davidov-Pardo, Gabriel; Gumus, Cansu Ekin; McClements, David Julian

    2016-04-01

    Lutein may be utilized in foods as a natural pigment or nutraceutical ingredient to improve eye health. Nevertheless, its use is limited by its poor water-solubility and chemical instability. We evaluated the effect of storage temperature and pH on the physical and chemical stability of lutein-enriched emulsions prepared using caseinate. The emulsions (initial droplet diameter=232 nm) remained physically stable at all incubation temperatures (5-70 °C); however the chemical degradation of lutein increased with increasing temperature (activation energy=38 kJ/mol). Solution pH had a major impact on the physical stability of the emulsions, causing droplet aggregation at pH 4 and 5. Conversely, the chemical stability of lutein was largely independent of the pH, with only a slight decrease in degradation at pH 8. This work provides important information for the rational design of emulsion-based delivery systems for a lipophilic natural dye and nutraceutical.

  8. In vitro skin permeation of sunscreen agents from O/W emulsions.

    PubMed

    Montenegro, L; Carbone, C; Paolino, D; Drago, R; Stancampiano, A H; Puglisi, G

    2008-02-01

    The effects of different emulsifiers on the in vitro permeation through human skin of two sunscreen agents [octylmethoxycinnamate (OMC) and butylmethoxydibenzoylmethane (BMBM)] were investigated from O/W emulsions. The test formulations were prepared using the same oil and aqueous phase ingredients and the following emulsifier and coemulsifier systems: Emulgade SE((R)) (ceteareth-12 and ceteareth-20 and cetearyl alcohol and cetyl palmitate) and glycerylmonostearate (emulsion 1); Brij 72((R)) (steareth-2), Brij 721((R)) (steareth-21) and cetearyl alcohol (emulsion 2); Phytocream((R)) (potassium palmitoyl-hydrolysed wheat protein and glyceryl stearate and cetearyl alcohol) and glycerylmonostearate (emulsion 3); Montanov 68((R)) (cetearyl glucoside and cetearyl alcohol) (emulsion 4); Xalifin-15((R)) (C(15-20) acid PEG-8 ester) and cetearyl alcohol (emulsion 5). The cumulative amount of OMC that permeated in vitro through human skin after 22 h from the formulations being tested decreased in the order 3 > 1 congruent with 4 > 5 > 2 and was about nine-fold higher from emulsion 3 compared with that from emulsion 2. As regards BMBM, no significant difference was observed as regards its skin permeation from emulsions 1, 3, 4 and 5, whereas formulation 2 allowed significantly lower amounts of BMBM to permeate the skin. In vitro release experiments of OMC and BMBM from emulsions 1-6 through cellulose acetate membranes showed that only emulsions 4 and 5 provided pseudo-first-order release rates only for OMC. The results of this study suggest that the type of emulsifying systems used to prepare an O/W emulsion may strongly affect sunscreen skin permeation from these formulations. Therefore, the vehicle effects should be carefully considered in the formulation of sunscreen products.

  9. Plasma fatty acids in premature infants with hyperbilirubinemia: before-and-after nutrition support with fish oil emulsion.

    PubMed

    Klein, Catherine J; Havranek, Thomas G; Revenis, Mary E; Hassanali, Zahra; Scavo, Louis M

    2013-02-01

    Infants who are dependent on parenteral nutrition (PN) sometimes develop PN-associated cholestasis (PNAC). A compassionate use protocol, approved by the U.S. Food and Drug Administration and the institutional review board, guided enrollment of hospitalized infants with PNAC (<1 year of age, PN dependence for >3 weeks). Plasma concentrations of essential fatty acids were monitored before and after a soybean-based PN lipid, infused at 3 g/kg body weight/d, was replaced by an experimental fish oil-based intravenous fat emulsion (FO-IVFE) at 1.0 g/kg/d. All participants were born premature (n = 10; 20% male). At enrollment, infants were (mean ± SD) 86.5 ± 53.5 days of life and weighed 2.24 ± 0.87 kg; direct bilirubin was 5.5 ± 1.3 mg/dL. After treatment, blood concentrations significantly increased from baseline (P < .017) for circulating eicosapentaenoic acid (6.3 ± 3.0 to 147.8 ± 53.1 µg/mL), docosahexaenoic acid (20.7 ± 6.5 to 163.7 ± 43.4 µg/mL), pristanic acid (0.01 ± 0.01 to 0.17 ± 0.03 µg/mL), and phytanic acid (0.06 ± 0.03 to 0.64 ± 0.15 µg/mL). In contrast, total plasma ω-6 fatty acids (including linoleic acid) decreased (P < .017). The triene/tetraene ratio remained below the threshold value of 0.2 that defines ω-6 deficiency. No adverse effects were observed attributable to FO-IVFE. Discontinuation of FO-IVFE was typically due to infants (body weight 3.76 ± 1.68 kg) transitioning to enteral feeding rather than for resolution of hyperbilirubinemia (direct bilirubin 7.9 ± 4.8 mg/dL). These exploratory results suggest that FO-IVFE raises circulating ω-3 fatty acids in premature infants without development of ω-6 deficiency in the 8.3 ± 5.8-week time frame of this study.

  10. Emulsions for interfacial filtration.

    SciTech Connect

    Grillet, Anne Mary; Bourdon, Christopher Jay; Souza, Caroline Ann; Welk, Margaret Ellen; Hartenberger, Joel David; Brooks, Carlton, F.

    2006-11-01

    We have investigated a novel emulsion interfacial filter that is applicable for a wide range of materials, from nano-particles to cells and bacteria. This technology uses the interface between the two immiscible phases as the active surface area for adsorption of targeted materials. We showed that emulsion interfaces can effectively collect and trap materials from aqueous solution. We tested two aqueous systems, a bovine serum albumin (BSA) solution and coal bed methane produced water (CBMPW). Using a pendant drop technique to monitor the interfacial tension, we demonstrated that materials in both samples were adsorbed to the liquid-liquid interface, and did not readily desorb. A prototype system was built to test the emulsion interfacial filter concept. For the BSA system, a protein assay showed a progressive decrease in the residual BSA concentration as the sample was processed. Based on the initial prototype operation, we propose an improved system design.

  11. Optimization of a gelled emulsion intended to supply ω-3 fatty acids into meat products by means of response surface methodology.

    PubMed

    Poyato, Candelaria; Ansorena, Diana; Berasategi, Izaskun; Navarro-Blasco, Iñigo; Astiasarán, Iciar

    2014-12-01

    The optimization of a gelled oil-in-water emulsion was performed for use as fat replacer in the formulation of ω-3 PUFA-enriched cooked meat products. The linseed oil content, carrageenan concentration and surfactant-oil ratio were properly combined in a surface response design for maximizing the hardness and minimizing the syneresis of the PUFA delivery system. The optimal formulation resulted in a gelled emulsion containing 40% of oil and 1.5% of carrageenan, keeping a surfactant-oil ratio of 0.003. The gel was applied as a partial fat replacer in a Bologna-type sausage and compared to the use of an O/W emulsion also enriched in ω-3. Both experimental sausages contributed with higher ω-3 PUFA content than the control. No sensory differences were found among formulations. The selected optimized gelled oil-in-water emulsion was demonstrated to be a suitable lipophilic delivery system for ω-3 PUFA compounds and applicable in food formulations as fat replacer.

  12. Rheology as a Tool to Predict the Release of Alpha-Lipoic Acid from Emulsions Used for the Prevention of Skin Aging

    PubMed Central

    Isaac, Vera Lucia Borges; Chiari-Andréo, Bruna Galdorfini; Marto, Joana Marques; Moraes, Jemima Daniela Dias; Leone, Beatriz Alves; Corrêa, Marcos Antonio; Ribeiro, Helena Margarida

    2015-01-01

    The availability of an active substance through the skin depends basically on two consecutive steps: the release of this substance from the vehicle and its subsequent permeation through the skin. Hence, studies on the specific properties of vehicles, such as their rheological behavior, are of great interest in the field of dermatological products. Recent studies have shown the influence of the rheological features of a vehicle on the release of drugs and active compounds from the formulation. In this context, the aim of this study was to evaluate the influence of the rheological features of two different emulsion formulations on the release of alpha-lipoic acid. Alpha-lipoic acid (ALA) was chosen for this study because of its antioxidant characteristics, which could be useful for the prevention of skin diseases and aging. The rheological and mechanical behavior and the in vitro release profile were assayed. The results showed that rheological features, such as viscosity, thixotropy, and compliance, strongly influenced the release of ALA from the emulsion and that the presence of a hydrophilic polymer in one of the emulsions was an important factor affecting the rheology and, therefore, the release of ALA. PMID:26788510

  13. Rheology as a Tool to Predict the Release of Alpha-Lipoic Acid from Emulsions Used for the Prevention of Skin Aging.

    PubMed

    Isaac, Vera Lucia Borges; Chiari-Andréo, Bruna Galdorfini; Marto, Joana Marques; Moraes, Jemima Daniela Dias; Leone, Beatriz Alves; Corrêa, Marcos Antonio; Ribeiro, Helena Margarida

    2015-01-01

    The availability of an active substance through the skin depends basically on two consecutive steps: the release of this substance from the vehicle and its subsequent permeation through the skin. Hence, studies on the specific properties of vehicles, such as their rheological behavior, are of great interest in the field of dermatological products. Recent studies have shown the influence of the rheological features of a vehicle on the release of drugs and active compounds from the formulation. In this context, the aim of this study was to evaluate the influence of the rheological features of two different emulsion formulations on the release of alpha-lipoic acid. Alpha-lipoic acid (ALA) was chosen for this study because of its antioxidant characteristics, which could be useful for the prevention of skin diseases and aging. The rheological and mechanical behavior and the in vitro release profile were assayed. The results showed that rheological features, such as viscosity, thixotropy, and compliance, strongly influenced the release of ALA from the emulsion and that the presence of a hydrophilic polymer in one of the emulsions was an important factor affecting the rheology and, therefore, the release of ALA.

  14. Cyclodextrin stabilised emulsions and cyclodextrinosomes.

    PubMed

    Mathapa, Baghali G; Paunov, Vesselin N

    2013-11-07

    We report the preparation of o/w emulsions stabilised by microcrystals of cyclodextrin-oil inclusion complexes. The inclusion complexes are formed by threading cyclodextrins from the aqueous phase on n-tetradecane or silicone oil molecules from the emulsion drop surface which grow further into microrods and microplatelets depending on the type of cyclodextrin (CD) used. These microcrystals remain attached on the surface of the emulsion drops and form densely packed layers which resemble Pickering emulsions. The novelty of this emulsion stabilisation mechanism is that molecularly dissolved cyclodextrin from the continuous aqueous phase is assembled into colloid particles directly onto the emulsion drop surface, i.e. molecular adsorption leads to effective Pickering stabilisation. The β-CD stabilised tetradecane-in-water emulsions were so stable that we used this system as a template for preparation of cyclodextrinosomes. These structures were produced solely through formation of cyclodextrin-oil inclusion complexes and their assembly into a crystalline phase on the drop surface retained its stability after the removal of the core oil. The structures of CD-stabilised tetradecane-in-water emulsions were characterised using optical microscopy, fluorescence microscopy, cross-polarised light microscopy and WETSEM while the cyclodextrinosomes were characterised by SEM. We also report the preparation of CD-stabilised emulsions with a range of other oils, including tricaprylin, silicone oil, isopropyl myristate and sunflower oil. We studied the effect of the salt concentration in the aqueous phase, the type of CD and the oil volume fraction on the type of emulsion formed. The CD-stabilised emulsions can be applied in a range of surfactant-free formulations with possible applications in cosmetics, home and personal care. Cyclodextrinosomes could find applications in pharmaceutical formulations as microencapsulation and drug delivery vehicles.

  15. Immunogenicity studies of bivalent inactivated virions of EV71/CVA16 formulated with submicron emulsion systems.

    PubMed

    Lin, Chih-Wei; Liu, Chia-Chyi; Lu, Tsung-Chun; Liu, Shih-Jen; Chow, Yen-Hung; Chong, Pele; Huang, Ming-Hsi

    2014-01-01

    We assessed two strategies for preparing candidate vaccines against hand, foot, and mouth disease (HFMD) caused mainly by infections of enterovirus (EV) 71 and coxsackievirus (CV) A16. We firstly design and optimize the potency of adjuvant combinations of emulsion-based delivery systems, using EV71 candidate vaccine as a model. We then perform immunogenicity studies in mice of EV71/CVA16 antigen combinations formulated with PELC/CpG. A single dose of inactivated EV71 virion (0.2 μg) emulsified in submicron particles was found (i) to induce potent antigen-specific neutralizing antibody responses and (ii) consistently to elicit broad antibody responses against EV71 neutralization epitopes. A single dose immunogenicity study of bivalent activated EV71/CVA16 virion formulated with either Alum or PELC/CpG adjuvant showed that CVA16 antigen failed to elicit CVA16 neutralizing antibody responses and did not affect EV71-specific neutralizing antibody responses. A boosting dose of emulsified EV71/CVA16 bivalent vaccine candidate was found to be necessary to achieve high seroconversion of CVA16-specific neutralizing antibody responses. The current results are important for the design and development of prophylactic vaccines against HFMD and other emerging infectious diseases.

  16. Comparative real-time study of cellular uptake of a formulated conjugated linolenic acid rich nano and conventional macro emulsions and their bioactivity in ex vivo models for parenteral applications.

    PubMed

    Paul, Debjyoti; Mukherjee, Sayani; Chakraborty, Rajarshi; Mallick, Sanjaya K; Dhar, Pubali

    2015-02-01

    The objective of the present study was to fabricate and monitor real-time, impact of a stable conjugated linolenic acid, α-eleostearic acid (ESA) rich nanoemulsion (NE) formulation (d < 200 nm) vis-à-vis ESA conventional emulsion (CE) system in ex vivo systems against both endogenous and exogenous reactive oxygen species (ROS). Accordingly, stable nanoemulsion formulation of ESA was engineered with the aid of bitter melon seed oil and non-toxic excipients. Morphology and particle size of the emulsion formulations were studied to validate stability. The real-time rapid uptake of the ESA NE and its increased prophylactic efficacy against induced endogenous and exogenous ROS in terms of cell viability and membrane integrity was evaluated flow-cytometrically and with fluorescence microscopic analysis of different primary cells. It was found that the fabricated non-toxic ESA NE had stable parameters (hydrodynamic mean diameter, particle size distribution and zeta potential) for over 12 weeks. Further, ESA NE at a concentration of ∼ 70 μM exhibited maximum efficacy in protecting cells from oxidative damage against both endogenous and exogenous ROS in lymphocytes and hepatocytes as compared to its corresponding presence in the CE formulation. This study provides a real-time empirical evidence on the influence of nano formulation in enhancing bioavailability and antioxidative properties of ESA.

  17. Fatty Acid Oxidation and Calcium Homeostasis are Involved in the Rescue of Bupivacaine Induced Cardiotoxicity by Lipid Emulsion in Rats

    PubMed Central

    Partownavid, Parisa; Umar, Soban; Li, Jingyuan; Rahman, Siamak; Eghbali, Mansoureh

    2012-01-01

    OBJECTIVES Lipid Emulsion (LE) has been shown to be effective in resuscitating bupivacaine-induced cardiac arrest but its mechanism of action is not clear. Here we investigated whether fatty acid oxidation is required for rescue of bupivacaine induced cardiotoxicity by LE in rats. We also compared the mitochondrial function and calcium threshold for triggering of mitochondrial permeability transition pore (mPTP) opening in bupivacaine-induced cardiac arrest before and after resuscitation with LE. DESIGN Prospective, randomized, animal study. SETTING University Research Laboratory. SUBJECTS Adult male Sprague-Dawley rats. INTERVENTIONS Asystole was achieved with a single dose of bupivacaine (10mg/kg over 20seconds, i.v.) and 20% LE infusion (5ml/kg bolus, and 0.5ml/kg/min maintenance) with cardiac massage started immediately. The rats in CVT group were pretreated with a single dose of fatty acid oxidation inhibitor CVT (0.5, 0.25, 0.125 or 0.0625mg/kg bolus i.v.) 5min prior to inducing asystole by bupivacaine overdose. Heart rate (HR), ejection fraction (EF), fractional shortening (FS), the threshold for opening of mPTP, oxygen consumption and membrane potential were measured. The values are Mean±SEM. MEASUREMENTS AND MAIN RESULTS Administration of bupivacaine resulted in asystole. ILP infusion improved the cardiac function gradually as the EF was fully recovered within 5min (EF=64±4% and FS=36±3%, n=6) and heart rate increased to 239±9 beats/min (71% recovery, n=6) within 10min. LE was only able to rescue rats pretreated with low dose of CVT (0.0625mg/kg) (HR=~181±11 beats/min at 10 min, recovery of 56%; EF=50±1%; FS=26±0.6% at 5min, n=3) but was unable to resuscitate rats pretreated with higher doses of CVT (0.5, 0.25 or 0.125mg/kg). The calcium retention capacity in response to Ca2+ overload was significantly higher in cardiac mitochondria isolated from rats resuscitated with 20% LE compared to the group that did not receive ILP after bupivacaine

  18. Controlling molecular transport in minimal emulsions

    PubMed Central

    Gruner, Philipp; Riechers, Birte; Semin, Benoît; Lim, Jiseok; Johnston, Abigail; Short, Kathleen; Baret, Jean-Christophe

    2016-01-01

    Emulsions are metastable dispersions in which molecular transport is a major mechanism driving the system towards its state of minimal energy. Determining the underlying mechanisms of molecular transport between droplets is challenging due to the complexity of a typical emulsion system. Here we introduce the concept of ‘minimal emulsions', which are controlled emulsions produced using microfluidic tools, simplifying an emulsion down to its minimal set of relevant parameters. We use these minimal emulsions to unravel the fundamentals of transport of small organic molecules in water-in-fluorinated-oil emulsions, a system of great interest for biotechnological applications. Our results are of practical relevance to guarantee a sustainable compartmentalization of compounds in droplet microreactors and to design new strategies for the dynamic control of droplet compositions. PMID:26797564

  19. Controlling molecular transport in minimal emulsions

    NASA Astrophysics Data System (ADS)

    Gruner, Philipp; Riechers, Birte; Semin, Benoît; Lim, Jiseok; Johnston, Abigail; Short, Kathleen; Baret, Jean-Christophe

    2016-01-01

    Emulsions are metastable dispersions in which molecular transport is a major mechanism driving the system towards its state of minimal energy. Determining the underlying mechanisms of molecular transport between droplets is challenging due to the complexity of a typical emulsion system. Here we introduce the concept of `minimal emulsions', which are controlled emulsions produced using microfluidic tools, simplifying an emulsion down to its minimal set of relevant parameters. We use these minimal emulsions to unravel the fundamentals of transport of small organic molecules in water-in-fluorinated-oil emulsions, a system of great interest for biotechnological applications. Our results are of practical relevance to guarantee a sustainable compartmentalization of compounds in droplet microreactors and to design new strategies for the dynamic control of droplet compositions.

  20. Synthesis of acyl arbutin by an immobilized lipase and its suppressive ability against lipid oxidation in a bulk system and O/W emulsion.

    PubMed

    Nagai, Mizuka; Watanabe, Yoshiyuki; Nomura, Masato

    2009-11-01

    Acyl arbutin was synthesized through the condensation of arbutin with a saturated fatty acid (C6-18) by the immobilized lipase in a batch reaction. The conversion at 10 and 20 g/l-solvent of immobilized lipase reached 45% over 2 d, but the initial reaction rate per amount of immobilized lipase decreased at 20 g/l-solvent. The radical scavenging activity of acyl arbutin in an ethanol solution was independent of the acyl chain length, although the rate constant, k, estimated for the oxidation of methyl linoleate in a bulk system with acyl arbutin by using the Weibull equation, decreased as the acyl chain length increased. This indicates the antioxidative ability of acyl arbutin with a long acyl chain to be due to its lipophilicity. Furthermore, it is suggested that dodecanoyl arbutin mainly acted on the interface between the oil and water phases in an O/W emulsion, and effectively suppressed the oxidation induced at the interface.

  1. Rejuvenation of Spent Media via Supported Emulsion Liquid Membranes

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.

    2002-01-01

    The overall goal of this project is to maximize the reuseability of spent fermentation media. Supported emulsion liquid membrane separation, a highly efficient extraction technique, is used to remove inhibitory byproducts during fermentation; thus, improving the yield while reducing the need for fresh water. The key objectives of this study are: Develop an emulsion liquid membrane system targeting low molecular weight organic acids which has minimal toxicity on a variety of microbial systems; Conduct mass transfer studies to allow proper modeling and design of a supported emulsion liquid membrane system; Investigate the effect of gravity on emulsion coalescence within the membrane unit; Access the effect of water re-use on fermentation yields in a model microbial system; Develop a perfusion-type fermentor utilizing a supported emulsion liquid membrane system to control inhibitory fermentation byproducts; Work for the coming year will focus on the determination of toxicity of various solvents, selection of the emulsifying agents, as well as characterizing the mass transfer of hollow-fiber contactors.

  2. Optimization of cyanide extraction from wastewater using emulsion liquid membrane system by response surface methodology.

    PubMed

    Xue, Juan Qin; Liu, Ni Na; Li, Guo Ping; Dang, Long Tao

    To solve the disposal problem of cyanide wastewater, removal of cyanide from wastewater using a water-in-oil emulsion type of emulsion liquid membrane (ELM) was studied in this work. Specifically, the effects of surfactant Span-80, carrier trioctylamine (TOA), stripping agent NaOH solution and the emulsion-to-external-phase-volume ratio on removal of cyanide were investigated. Removal of total cyanide was determined using the silver nitrate titration method. Regression analysis and optimization of the conditions were conducted using the Design-Expert software and response surface methodology (RSM). The actual cyanide removals and the removals predicted using RSM analysis were in close agreement, and the optimal conditions were determined to be as follows: the volume fraction of Span-80, 4% (v/v); the volume fraction of TOA, 4% (v/v); the concentration of NaOH, 1% (w/v); and the emulsion-to-external-phase volume ratio, 1:7. Under the optimum conditions, the removal of total cyanide was 95.07%, and the RSM predicted removal was 94.90%, with a small exception. The treatment of cyanide wastewater using an ELM is an effective technique for application in industry.

  3. Preparation of stable Pickering emulsions with short, medium and long chain fats and starch nanocrystals and their in vitro digestion properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pickering emulsions are receiving more attention as delivery systems in food and pharmaceuticals because they can be formulated with nontoxic food ingredients to form stable emulsions. In this study, 40-100 nm starch nanocrystals (SNCs) prepared from acid hydrolysis of waxy maize starches were used ...

  4. α-Tocopherol/chitosan-based nanoparticles: characterization and preliminary investigations for emulsion systems application

    NASA Astrophysics Data System (ADS)

    Aresta, Antonella; Calvano, Cosima Damiana; Trapani, Adriana; Zambonin, Carlo Giorgio; De Giglio, Elvira

    2014-02-01

    The processes of lipids oxidation represent a great concern for the consumer health because they are one of the major causes of quality deterioration in fat-containing products. One of the most effective methods of delaying lipid oxidation consists in incorporating antioxidants. The present investigation describes the formulation of chitosan and novel glycol chitosan nanoparticles (NPs) loaded with α-Tocopherol (αToc-NPs). The obtained NPs were characterized by various techniques, such as particle size (showing mean diameters in the range 335-503 nm) and zeta potential measurements, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The NPs were, then, added in the preparation of oil-in-water simple emulsion both to make the lipophilic αToc available in an aqueous medium and to prevent emulsion oxidation. For this purpose, a new highly sensitive, simple and solvent-free method based on a solid phase microextraction (SPME) coupled to gas chromatography mass spectrometry was developed for the determination of αToc in aqueous medium. All the parameters influencing SPME, including fiber coating, time and temperature extraction, pH, ionic strength and desorption conditions, have been carefully screened. The method was successfully applied to the determination of vitamin in the αToc-NPs and its release from NPs-enriched simple emulsion formulations. SPME provided high recovery yields and the limits of detection and of quantification in emulsion were 0.1 and 0.5 μg/mg, respectively. The precision of the method has been also estimated. The delay of the lipid oxidation by the proposed formulations has been evaluated exploiting the Kreis test on αToc-NPs-enriched emulsions.

  5. O/W nano-emulsion formation using an isothermal low-energy emulsification method in a mixture of polyglycerol polyricinoleate and hexaglycerol monolaurate with glycerol system.

    PubMed

    Wakisaka, Satoshi; Nishimura, Takahisa; Gohtani, Shoichi

    2015-01-01

    We investigated how phase behavior changes by replacing water with glycerol in water/mixture of polyglycerol polyricinoleate (PGPR) and hexaglycerol monolaurate (HGML) /vegetable oil system, and studied the effect of glycerol on o/w nano-emulsion formation using an isothermal low-energy method. In the phase behavior study, the liquid crystalline phase (Lc) + the sponge phase (L3) expanded toward lower surfactant concentration when water was replaced with glycerol in a system containing surfactant HLP (a mixture of PGPR and HGML). O/W nano-emulsions were formed by emulsification of samples in a region of Lc + L3. In the glycerol/surfactant HLP/vegetable oil system, replacing water with glycerol was responsible for the expansion of a region containing Lc + L3 toward lower surfactant concentration, and as a result, in the glycerol/surfactant HLP/vegetable oil system, the region where o/w nano-emulsions or o/w emulsions could be prepared using an isothermal low-energy emulsification method was wide, and the droplet diameter of the prepared o/w emulsions was also smaller than that in the water/surfactant HLP/vegetable oil system. Therefore, glycerol was confirmed to facilitate the preparation of nano-emulsions from a system of surfactant HLP. Moreover, in this study, we could prepare o/w nano-emulsions with a simple one-step addition of water at room temperature without using a stirrer. Thus, the present technique is highly valuable for applications in several industries.

  6. Effects of parenteral infusion with fish-oil or safflower-oil emulsion on hepatic lipids, plasma amino acids, and inflammatory mediators in septic rats.

    PubMed

    Chao, C Y; Yeh, S L; Lin, M T; Chen, W J

    2000-04-01

    This study was designed to investigate the effects of preinfusion with total parenteral nutrition (TPN) using fish-oil (FO) versus safflower-oil (SO) emulsion as fat sources on hepatic lipids, plasma amino-acid profiles, and inflammatory-related mediators in septic rats. Normal rats, with internal jugular catheters, were assigned to two different groups and received TPN. TPN provided 300 kcal. kg(-1). d(-1), with 40% of the non-protein energy as fat. All TPN solutions were isonitrogenous and identical in nutrient composition except for the fat emulsion, which was made of SO or FO. After receiving TPN for 6 d, each group of rats was further divided into control and sepsis subgroups. Sepsis was induced by cecal ligation and puncture; control rats received sham operation. All rats were classified into four groups as follows: FO control group (FOC; n = 7), FO sepsis group (FOS; n = 8), SO control group (SOC; n = 8), and SO sepsis group (SOS; n = 9). The results of the study demonstrated that plasma concentrations of triacylglycerol and non-esterified fatty acids did not differ between the FO and SO groups, regardless of whether the animals were septic. SOS had significantly higher total lipids and cholesterol content in the liver than did the SOC group. The FOS group, however, showed no difference from the FOC group. Plasma leucine and isoleucine levels were significantly lower in the SOS group than in the SOC group, whereas no difference in these two amino acids was observed between the FOC and FOS groups. Plasma arginine levels were significantly lower in both septic groups than in the groups without sepsis when either FO or SO was infused. Plasma glutamine levels, however, did not differ across groups. No differences in interleukin-1beta, interleukin-6, tumor necrosis factor-alpha, or leukotriene B(4) concentrations in peritoneal lavage fluid were observed between the two septic groups. These results suggest that catabolic reaction in septic rats preinfused with FO

  7. Facile fabrication of poly(L-lactic acid) microsphere-incorporated calcium alginate/hydroxyapatite porous scaffolds based on Pickering emulsion templates.

    PubMed

    Hu, Yang; Ma, Shanshan; Yang, Zhuohong; Zhou, Wuyi; Du, Zhengshan; Huang, Jian; Yi, Huan; Wang, Chaoyang

    2016-04-01

    In this study, we develop a facile one-pot approach to the fabrication of poly(L-lactic acid) (PLLA) microsphere-incorporated calcium alginate (ALG-Ca)/hydroxyapatite (HAp) porous scaffolds based on HAp nanoparticle-stabilized oil-in-water Pickering emulsion templates, which contain alginate in the aqueous phase and PLLA in the oil phase. The emulsion aqueous phase is solidified by in situ gelation of alginate with Ca(2+) released from HAp by decreasing pH with slow hydrolysis of D-gluconic acid δ-lactone (GDL) to produce emulsion droplet-incorporated gels, followed by freeze-drying to form porous scaffolds containing microspheres. The pore structure of porous scaffolds can be adjusted by varying the HAp or GDL concentration. The compressive tests show that the increase of HAp or GDL concentration is beneficial to improve the compressive property of porous scaffolds, while the excessive HAp can lead to the decrease in compressive property. Moreover, the swelling behavior studies display that the swelling ratios of porous scaffolds reduce with increasing HAp or GDL concentration. Furthermore, hydrophobic drug ibuprofen (IBU) and hydrophilic drug bovine serum albumin (BSA) are loaded into the microspheres and scaffold matrix, respectively. In vitro drug release results indicate that BSA has a rapid release while IBU has a sustained release in the dual drug-loaded scaffolds. In vitro cell culture experiments verify that mouse bone mesenchymal stem cells can proliferate on the porous scaffolds well, indicating the good biocompatibility of porous scaffolds. All these results demonstrate that the PLLA microsphere-incorporated ALG-Ca/HAp porous scaffolds have a promising potential for tissue engineering and drug delivery applications.

  8. Intravenous Lipid Emulsions in Parenteral Nutrition123

    PubMed Central

    Fell, Gillian L; Nandivada, Prathima; Gura, Kathleen M; Puder, Mark

    2015-01-01

    Fat is an important macronutrient in the human diet. For patients with intestinal failure who are unable to absorb nutrients via the enteral route, intravenous lipid emulsions play a critical role in providing an energy-dense source of calories and supplying the essential fatty acids that cannot be endogenously synthesized. Over the last 50 y, lipid emulsions have been an important component of parenteral nutrition (PN), and over the last 10–15 y many new lipid emulsions have been manufactured with the goal of improving safety and efficacy profiles and achieving physiologically optimal formulations. The purpose of this review is to provide a background on the components of lipid emulsions, their role in PN, and to discuss the lipid emulsions available for intravenous use. Finally, the role of parenteral fat emulsions in the pathogenesis and management of PN-associated liver disease in PN-dependent pediatric patients is reviewed. PMID:26374182

  9. Galantamine-loaded PLGA nanoparticles, from nano-emulsion templating, as novel advanced drug delivery systems to treat neurodegenerative diseases

    NASA Astrophysics Data System (ADS)

    Fornaguera, C.; Feiner-Gracia, N.; Calderó, G.; García-Celma, M. J.; Solans, C.

    2015-07-01

    Polymeric nanoparticles could be promising drug delivery systems to treat neurodegenerative diseases. Among the various methods of nanoparticle preparation, nano-emulsion templating was used in the present study to prepare galantamine-loaded nano-emulsions by a low-energy emulsification method followed by solvent evaporation to obtain galantamine-loaded polymeric nanoparticles. This approach was found to be suitable because biocompatible, biodegradable and safe nanoparticles with appropriate features (hydrodynamic radii around 20 nm, negative surface charge and stability higher than 3 months) for their intravenous administration were obtained. Encapsulation efficiencies higher than 90 wt% were obtained with a sustained drug release profile as compared to that from aqueous and micellar solutions. The enzymatic activity of the drug was maintained at 80% after its encapsulation into nanoparticles that were non-cytotoxic at the required therapeutic concentration. Therefore, novel galantamine-loaded polymeric nanoparticles have been designed for the first time using the nano-emulsification approach and showed the appropriate features to become advanced drug delivery systems to treat neurodegenerative diseases.Polymeric nanoparticles could be promising drug delivery systems to treat neurodegenerative diseases. Among the various methods of nanoparticle preparation, nano-emulsion templating was used in the present study to prepare galantamine-loaded nano-emulsions by a low-energy emulsification method followed by solvent evaporation to obtain galantamine-loaded polymeric nanoparticles. This approach was found to be suitable because biocompatible, biodegradable and safe nanoparticles with appropriate features (hydrodynamic radii around 20 nm, negative surface charge and stability higher than 3 months) for their intravenous administration were obtained. Encapsulation efficiencies higher than 90 wt% were obtained with a sustained drug release profile as compared to that from

  10. Shear flow behaviour and emulsion-stabilizing effect of natural polysaccharide-protein gum in aqueous system and oil/water (O/W) emulsion.

    PubMed

    Amid, Bahareh Tabatabaee; Mirhosseini, Hamed

    2013-03-01

    The main objective of the current work was to characterize the shear rheological flow behaviour and emulsifying properties of the natural biopolymer from durian seed. The present study revealed that the extraction condition significantly affected the physical and functional characteristics of the natural biopolymer from durian seed. The dynamic oscillatory test indicated that the biopolymer from durian seed showed more gel (or solid) like behaviour than the viscous (or liquid) like behaviour (G'>G″) at a relatively high concentration (20%) in the fixed frequency (0.1 Hz). This might be explained by the fact that the gum coils disentangle at low frequencies during the long period of oscillation, thus resulting in more gel like behaviour than the viscous like behaviour. The average droplet size of oil in water (O/W) emulsions stabilized by durian seed gum significantly varied from 0.42 to 7.48 μm. The results indicated that O/W emulsions showed significant different stability after 4 months storage. This might be interpreted by the considerable effect of the extraction condition on the chemical and molecular structure of the biopolymer, thus affecting its emulsifying capacity. The biopolymer extracted by using low water to seed (W/S) ratio at the low temperature under the alkaline condition showed a relatively high emulsifying activity in O/W emulsion.

  11. Relationship between internal phase volume and emulsion stability: the cetyl alcohol/stearyl alcohol system.

    PubMed

    Sepulveda, E; Kildsig, D O; Ghaly, E S

    2003-08-01

    The main objective of this study was to optimize the stability of cetyl alcohol/stearyl alcohol emulsions in terms of percentage of internal phase volume, emulsifier type and concentration, and amount of external phase (water). Creams (o/w emulsions) were prepared by phase inversion and physical properties as particle size of the internal phase, apparent viscosity, and sedimentation volume evaluated. Stability was performed at room temperature, 40 degrees C, 50 degrees C, and under stress conditions. High hydrophilic lipophilic balance (HLB) nonionic surfactants as tween 80, tween 20, Myrj 52, Brij 35, and low HLB span 60 were used as emulsifying agents. The percentage of internal phase components (cetyl alcohol and stearyl alcohol), percentage of emulsifying agents, and percentage of aqueous external phase were varied, and stability was investigated. As the level of emulsifier agent (tween 80 and span 60) increased from 3% to 15%, and the percent of the internal phase remained constant at 30%, the particle size of the internal phase decreased and the cream became more stable. Formulations of the same composition, but prepared using Myrj 53 and tween 20 as emulsifiers, showed a larger particle size than formulations prepared using tween 80 and Brij 35. As the level of the internal phase volume increased and consequently the amount of water decreased, emulsion viscosity increased. The best formulation containing 30% internal phase (50% cetyl alcohol, 35% stearyl alcohol), 15% emulsifying agents (tween 80/span 60 ratio of 3:1), and 70% water was selected, and effects of process temperature and cooling rate on emulsion stability investigated. This formulation was further investigated in terms of stability of a 1% hydrocortisone addition by varying the percentage (30%, 35%, 40%, and 45%) of internal phase and percentage of water (70%, 65%, 60%, and 55%). The best formulation contained 45% internal phase (22.5 g cetyl alcohol, 15.75 g stearyl alcohol, 15% emulsifying

  12. Compartmentalization of incompatible reagents within Pickering emulsion droplets for one-pot cascade reactions.

    PubMed

    Yang, Hengquan; Fu, Luman; Wei, Lijuan; Liang, Jifen; Binks, Bernard P

    2015-01-28

    It is a dream that future synthetic chemistry can mimic living systems to process multistep cascade reactions in a one-pot fashion. One of the key challenges is the mutual destruction of incompatible or opposing reagents, for example, acid and base, oxidants and reductants. A conceptually novel strategy is developed here to address this challenge. This strategy is based on a layered Pickering emulsion system, which is obtained through lamination of Pickering emulsions. In this working Pickering emulsion, the dispersed phase can separately compartmentalize the incompatible reagents to avoid their mutual destruction, while the continuous phase allows other reagent molecules to diffuse freely to access the compartmentalized reagents for chemical reactions. The compartmentalization effects and molecular transport ability of the Pickering emulsion were investigated. The deacetalization-reduction, deacetalization-Knoevenagel, deacetalization-Henry and diazotization-iodization cascade reactions demonstrate well the versatility and flexibility of our strategy in processing the one-pot cascade reactions involving mutually destructive reagents.

  13. Effects on hemodynamics and gas exchange of omega-3 fatty acid-enriched lipid emulsion in acute respiratory distress syndrome (ARDS): a prospective, randomized, double-blind, parallel group study

    PubMed Central

    Sabater, Joan; Masclans, Joan Ramon; Sacanell, Judit; Chacon, Pilar; Sabin, Pilar; Planas, Merce

    2008-01-01

    Introduction We investigated the effects on hemodynamics and gas exchange of a lipid emulsion enriched with omega-3 fatty acids in patients with ARDS. Methods The design was a prospective, randomized, double-blind, parallel group study in our Intensive Medicine Department of Vall d'Hebron University Hospital (Barcelona-Spain). We studied 16 consecutive patients with ARDS and intolerance to enteral nutrition (14 men and 2 women; mean age: 58 ± 13 years; APACHE II score: 17.8 ± 2.3; Lung Injury Score: 3.1 ± 0.5; baseline PaO2/FiO2 ratio: 149 ± 40). Patients were randomized into 2 groups: Group A (n = 8) received the study emulsion Lipoplus® 20%, B.Braun Medical (50% MCT, 40% LCT, 10% ω-3); Group B (n = 8) received the control emulsion Intralipid® Fresenius Kabi (100% LCT). Lipid emulsions were administered during 12 h at a dose of 0.12 g/kg/h. Measurements of the main hemodynamic and gas exchange parameters were made at baseline (immediately before administration of the lipid emulsions), every hour during the lipid infusion, at the end of administration, and six hours after the end of administration lipid infusion. Results No statistically significant changes were observed in the different hemodynamic values analyzed. Likewise, the gas exchange parameters did not show statistically significant differences during the study. No adverse effect attributable to the lipid emulsions was seen in the patients analyzed. Conclusion The lipid emulsion enriched with omega-3 fatty acids was safe and well tolerated in short-term administration to patients with ARDS. It did not cause any significant changes in hemodynamic and gas exchange parameters. Trial registration ISRCTN63673813 PMID:18947396

  14. The interfacial pressure is an important parameter for the rate of phospholipase D catalyzed reactions in emulsion systems.

    PubMed

    Hirche, F; Ulbrich-Hofmann, R

    1999-01-04

    Phospholipase D (PLD) is widely used for the transformation of phospholipids, which is preferably performed in aqueous-organic emulsion systems. The influence of the organic solvent on the reaction rates has been studied on the hydrolysis of phosphatidylcholine (PC) and its transesterification with glycerol by two types of PLD (cabbage and Streptomyces sp.). The initial rates determined by quantitative HPTLC show great differences in dependence on the solvent used with a similar tendency for both reactions and both PLDs. Since the polymorphism of the PC aggregates was assumed to be responsible for these effects, the critical concentration of micelle formation, the size of the aggregates, the water content of the organic phase, and the interfacial tension were determined in the different reaction systems. As result the interfacial pressure in the reaction systems influencing the package density of the PC aggregates is suggested to regulate the enzymatic activity.

  15. A theory of electrophoresis of emulsion drops in aqueous two-phase polymer systems

    NASA Technical Reports Server (NTRS)

    Levine, S.

    1982-01-01

    An electrophoresis study has been carried out in an emulsion formed from an electrically neutral aqueous mixture of dextran and polyethylene glycol equilibrated at sufficient concentrations in the presence of electrolytes. Electrophoresis of a drop of one phase suspended in the other is observed, and the direction of the drop's motion is reversed when the disperse phase and the continuous phase are interchanged. In the presence of sulfate, phosphate, or citrate ions, an electrostatic potential difference of the order of a few mV exists between the two phases. The potential implied by the direction of the electrophoretic motion is opposite to the Donnan potential observed between the two phases. The mobility of an emulsion drop increases with the drop radius and depends on ion concentration. These results are explained in terms of a model postulating an electric dipole layer associated with a mixture of oriented polymer molecules at the surface of a drop, with a potential difference between the interiors of the two phases resulting from the unequal ion distribution.

  16. Emulsion culture: a miniaturized library screening system based on micro-droplets in an emulsified medium.

    PubMed

    Kojima, Takaaki; Nagao, Nobuhito; Ando, Daisuke; Ojima, Teruyo; Kawarasaki, Yasuaki; Kobayashi, Isao; Nakajima, Mitsutoshi; Nakano, Hideo

    2011-09-01

    A typical library screen in directed evolution primarily requires physical separation of the clones on agar plates followed by detection of clones with improved properties; using this method only limited numbers of clones relative to the number of potential variations can be assessed. In particular, screening for a secretory enzyme is difficult to perform at high clone density, because of diffusion of the signal or unfavorable utilization of the reaction product by neighboring clones. In this study, we have developed a novel method of enrichment culture: "Emulsion Culture", i.e., segregated replication of clones in an emulsified culture medium. Clones expressing enzyme-variants are separately distributed to small (up to 50 μm in diameter), segregated compartments composed of a droplet of medium to form several tens of millions of microcolonies in a milliliter of medium, which allows a miniaturized, in-bulk screening of clones. We applied this culture method to yeast clones expressing secretory beta-galactosidase to analyze the enrichment factor achieved. A high-density screen for a signal peptide sequence that maximizes extracellular production of the enzyme was also performed to demonstrate the practicability of this culture method. In addition, micro-channel emulsification was tested as a method of forming uniformly-sized compartments in the emulsion.

  17. Fabrication of Concentrated Fish Oil Emulsions Using Dual-Channel Microfluidization: Impact of Droplet Concentration on Physical Properties and Lipid Oxidation.

    PubMed

    Liu, Fuguo; Zhu, Zhenbao; Ma, Cuicui; Luo, Xiang; Bai, Long; Decker, Eric Andrew; Gao, Yanxiang; McClements, David Julian

    2016-12-21

    Chemically unstable lipophilic bioactives, such as polyunsaturated lipids, often have to be encapsulated in emulsion-based delivery systems before they can be incorporated into foods, supplements, and pharmaceuticals. The objective of this study was to develop highly concentrated emulsion-based fish oil delivery systems using natural emulsifiers. Fish oil-in-water emulsions were fabricated using a highly efficient dual-channel high-pressure microfluidizer. The impact of oil concentration on the formation, physical properties, and oxidative stability of fish oil emulsions prepared using two natural emulsifiers (quillaja saponins and rhamnolipids) and one synthetic emulsifier (Tween-80) was examined. The mean droplet size, polydispersity, and apparent viscosity of the fish oil emulsions increased with increasing oil content. However, physically stable emulsions with high fish oil levels (30 or 40 wt %) could be produced using all three emulsifiers, with rhamnolipids giving the smallest droplet size (d < 160 nm). The stability of the emulsions to lipid oxidation increased as the oil content increased. The oxidative stability of the emulsions also depended on the nature of the emulsifier coating the lipid droplets, with the oxidative stability decreasing in the following order: rhamnolipids > saponins ≈ Tween-80. These results suggest that rhamnolipids may be particularly effective at producing emulsions containing high concentrations of ω-3 polyunsaturated fatty acids-rich fish oil.

  18. Inhibitory activity of chlorogenic acids in decaffeinated green coffee beans against porcine pancreas lipase and effect of a decaffeinated green coffee bean extract on an emulsion of olive oil.

    PubMed

    Narita, Yusaku; Iwai, Kazuya; Fukunaga, Taiji; Nakagiri, Osamu

    2012-01-01

    A decaffeinated green coffee bean extract (DGCBE) inhibited porcine pancreas lipase (PPL) activity with an IC50 value of 1.98 mg/mL. Six different chlorogenic acids in DGCBE contributed to this PPL inhibition, accounting for 91.8% of the inhibitory activity. DGCBE increased the droplet size and decreased the specific surface area of an olive oil emulsion.

  19. Stimuli-responsive Pickering emulsions: recent advances and potential applications.

    PubMed

    Tang, Juntao; Quinlan, Patrick James; Tam, Kam Chiu

    2015-05-14

    Pickering emulsions possess many advantages over traditional surfactant stabilized emulsions. For example, Pickering emulsions impart better stability against coalescence and, in many cases, are biologically compatible and environmentally friendly. These characteristics open the door for their use in a variety of industries spanning petroleum, food, biomedicine, pharmaceuticals, and cosmetics. Depending on the application, rapid, but controlled stabilization and destabilization of an emulsion may be necessary. As a result, Pickering emulsions with stimuli-responsive properties have, in recent years, received a considerable amounts of attention. This paper provides a concise and comprehensive review of Pickering emulsion systems that possess the ability to respond to an array of external triggers, including pH, temperature, CO2 concentration, light intensity, ionic strength, and magnetic field. Potential applications for which stimuli-responsive Pickering emulsion systems would be of particular value, such as emulsion polymerization, enhanced oil recovery, catalyst recovery, and cosmetics, are discussed.

  20. Pharmaceutical emulsions: a new approach for gene therapy.

    PubMed

    Verissimo, Lourena Mafra; Lima, Lucymara Fassarela Agnez; Egito, Lucila Carmem Monte; de Oliveira, Anselmo Gomes; do Egito, E Sócrates Tabosa

    2010-06-01

    The concept of gene therapy involves the experimental transfer of a therapeutic gene into an individual's cells and tissues to replace an abnormal gene aiming to treat a disease, or to use the gene to treat a disease just like a medicine, improving the clinical status of a patient. The achievement of a foreigner nucleic acid into a population of cells requires its transfer to the target. Therefore, it is essential to create carriers (vectors) that transfer and protect the nucleic acid until it reaches the target. The obvious disadvantages of the use of viral vectors have directed the research for the development of a nonviral organized system such as emulsions. In fact, recently, there has been an increase of interest in its use in biotechnology as a nonviral vector for gene therapy. This review focuses on the progress of cationic emulsions and the improvement of the formulations, as a potential delivery system for gene therapy.

  1. Analysis system of submicron particle tracks in the fine-grained nuclear emulsion by a combination of hard x-ray and optical microscopy

    SciTech Connect

    Naka, T.; Asada, T.; Yoshimoto, M.; Katsuragawa, T.; Tawara, Y.; Umemoto, A.; Suzuki, Y.; Terada, Y.; Takeuchi, A.; Uesugi, K.; Kimura, M.

    2015-07-15

    Analyses of nuclear emulsion detectors that can detect and identify charged particles or radiation as tracks have typically utilized optical microscope systems because the targets have lengths from several μm to more than 1000 μm. For recent new nuclear emulsion detectors that can detect tracks of submicron length or less, the current readout systems are insufficient due to their poor resolution. In this study, we developed a new system and method using an optical microscope system for rough candidate selection and the hard X-ray microscope system at SPring-8 for high-precision analysis with a resolution of better than 70 nm resolution. Furthermore, we demonstrated the analysis of submicron-length tracks with a matching efficiency of more than 99% and position accuracy of better than 5 μm. This system is now running semi-automatically.

  2. Effectiveness of ω-3 Polyunsaturated Fatty Acids Based Lipid Emulsions for Treatment of Patients after Hepatectomy: A Prospective Clinical Trial

    PubMed Central

    Gong, Yuanfeng; Liu, Zhaohui; Liao, Yadi; Mai, Cong; Chen, Tiejun; Tang, Hui; Tang, Yunqiang

    2016-01-01

    Objective: The present study aimed to investigate the effectiveness of parenteral nutritional support with ω-3 PUFAs–based lipid emulsions in patients after liver resection. Methods: A total of 119 patients were randomly assigned to the immunonutrition (IM) group (n = 59) and control group (n = 60). The IM group was continuously given Omegaven® 10% 100 mL/day rather than regular nutrition for five days postoperatively. Venous blood samples were obtained from all subjects before surgery and D1, D3 and D7 after surgery. Results: No significant difference was found in baseline characteristics of the two groups. On D1 after surgery, no statistically significant differences were observed in the blood sample tests between the two groups. On D3 after surgery, the levels of white blood cell count (WBC), alanine aminotransferase (ALT), aspartate transaminase (AST) and total bilirubin (TBil) were dramatically decreased in the IM group (t = 3.065, p = 0.003; t = 2.149, p = 0.034; t = 5.313, p= 0.001; and t = 2.419, p = 0.017, respectively). Furthermore, on D7 after surgery, not only could a significant decrease be observed in the IM group concerning the levels of WBC, ALT and TBil (t = 3.025, p = 0.003; t = 2.094, p = 0.038; and t = 2.046, p = 0.043, respectively), but it was also seen in the level of Δprothrombintime (PT) (t = 2.450, p = 0.016). An increase in the level of prealbumin (Pre-Alb) in the IM group was observed on D7 after surgery (t = 2.237, p = 0.027). The frequency of total complications in the IM group were significantly lower than in the control group (χ2 = 4.225, p = 0.040 and χ2 = 3.174, p = 0.075). The trend favored the IM group in reducing the total infective complications rate (χ2 = 3.174, p = 0.075). A significant decrease in the duration of the hospital stay after surgery was also observed in the IM group (t = 2.012, p = 0.047).Conclusion: ω-3 PUFAs–based lipid emulsions for treatment of patients after hepatectomy are safe and effective in

  3. Dynamics of Polydisperse Coarsening Emulsion

    NASA Astrophysics Data System (ADS)

    Mirenda, Nic; Hicock, Harry; Feitosa, Klebert; Crocker, John

    2014-03-01

    Soft glassy materials display complex fluid behavior characterized by a yield stress and distinctive elastic and viscous moduli. The complexity emerges from the disordered structure and interactions between the athermal particles. Here we study the dynamics of an optically clear and neutrally buoyantly emulsion whose droplets coarsen driven by Laplace pressure induced diffusion. The emulsion displays an anomalous loss modulus typical of coarsening foam systems. We use confocal microscopy to image the droplets, measure their size and centroid location, and track their evolution in time. The relaxation process of the coarsening emulsion is found to be marked by a continuous, slow structural evolution interspersed by sudden droplet swaps. We characterize the time scales of each process and the statistics of droplet rearrangements. We acknowledge support from Research Corporation and NSF-DMR-1229383.

  4. Real-time measurements to characterize dynamics of emulsion interface during simulated intestinal digestion.

    PubMed

    Pan, Yuanjie; Nitin, N

    2016-05-01

    Efficient delivery of bioactives remains a critical challenge due to their limited bioavailability and solubility. While many encapsulation systems are designed to modulate the digestion and release of bioactives within the human gastrointestinal tract, there is limited understanding of how engineered structures influence the delivery of bioactives. The objective of this study was to develop a real-time quantitative method to measure structural changes in emulsion interface during simulated intestinal digestion and to correlate these changes with the release of free fatty acids (FFAs). Fluorescence resonant energy transfer (FRET) was used for rapid in-situ measurement of the structural changes in emulsion interface during simulated intestinal digestion. By using FRET, changes in the intermolecular spacing between the two different fluorescent probes labeled emulsifier were characterized. Changes in FRET measurements were compared with the release of FFAs. The results showed that bile salts and pancreatic lipase interacted immediately with the emulsion droplets and disrupted the emulsion interface as evidenced by reduction in FRET efficacy compared to the control. Similarly, a significant amount of FFAs was released during digestion. Moreover, addition of a second layer of polymers at emulsion interface decreased the extent of interface disruption by bile salts and pancreatic lipase and impacted the amount or rate of FFA release during digestion. These results were consistent with the lower donor/acceptor ratio of the labeled probes from the FRET result. Overall, this study provides a novel approach to analyze the dynamics of emulsion interface during digestion and their relationship with the release of FFAs.

  5. Performance of automatic scanning microscope for nuclear emulsion experiments

    NASA Astrophysics Data System (ADS)

    Güler, A. Murat; Altınok, Özgür

    2015-12-01

    The impressive improvements in scanning technology and methods let nuclear emulsion to be used as a target in recent large experiments. We report the performance of an automatic scanning microscope for nuclear emulsion experiments. After successful calibration and alignment of the system, we have reached 99% tracking efficiency for the minimum ionizing tracks that penetrating through the emulsions films. The automatic scanning system is successfully used for the scanning of emulsion films in the OPERA experiment and plan to use for the next generation of nuclear emulsion experiments.

  6. Performance of automatic scanning microscope for nuclear emulsion experiments

    SciTech Connect

    Güler, A. Murat; Altınok, Özgür

    2015-12-31

    The impressive improvements in scanning technology and methods let nuclear emulsion to be used as a target in recent large experiments. We report the performance of an automatic scanning microscope for nuclear emulsion experiments. After successful calibration and alignment of the system, we have reached 99% tracking efficiency for the minimum ionizing tracks that penetrating through the emulsions films. The automatic scanning system is successfully used for the scanning of emulsion films in the OPERA experiment and plan to use for the next generation of nuclear emulsion experiments.

  7. Suppression of Ostwald ripening in active emulsions

    NASA Astrophysics Data System (ADS)

    Zwicker, David; Hyman, Anthony A.; Jülicher, Frank

    2015-07-01

    Emulsions consisting of droplets immersed in a fluid are typically unstable since they coarsen over time. One important coarsening process is Ostwald ripening, which is driven by the surface tension of the droplets. Stability of emulsions is relevant not only in complex fluids but also in biological cells, which contain liquidlike compartments, e.g., germ granules, Cajal bodies, and centrosomes. Such cellular systems are driven away from equilibrium, e.g., by chemical reactions, and thus can be called active emulsions. In this paper, we study such active emulsions by developing a coarse-grained description of the droplet dynamics, which we analyze for two different chemical reaction schemes. We first consider the simple case of first-order reactions, which leads to stable, monodisperse emulsions in which Ostwald ripening is suppressed within a range of chemical reaction rates. We then consider autocatalytic droplets, which catalyze the production of their own droplet material. Spontaneous nucleation of autocatalytic droplets is strongly suppressed and their emulsions are typically unstable. We show that autocatalytic droplets can be nucleated reliably and their emulsions stabilized by the help of chemically active cores, which catalyze the production of droplet material. In summary, different reaction schemes and catalytic cores can be used to stabilize emulsions and to control their properties.

  8. Aging mechanism in model Pickering emulsion

    NASA Astrophysics Data System (ADS)

    Fouilloux, Sarah; Malloggi, Florent; Daillant, Jean; Thill, Antoine

    We study the stability of a model Pickering emulsion system. A special counter-flow microfluidics set-up was used to prepare monodisperse Pickering emulsions, with oil droplets in water. The wettability of the monodisperse silica nanoparticles (NPs) could be tuned by surface grafting and the surface coverage of the droplets was controlled using the microfluidics setup. A surface coverage as low as 23$\\%$ is enough to stabilize the emulsions and we evidence a new regime of Pickering emulsion stability where the surface coverage of emulsion droplets of constant size increases in time, in coexistence with a large amount of dispersed phase. Our results demonstrate that the previously observed limited coalescence regime where surface coverage tends to control the average size of the final droplets must be put in a broader perspective.

  9. [Interactions between cyclodextrins and triglycerides: from emulsion stabilisation to the emergence of a new drug delivery system called "beads"].

    PubMed

    Hamoudi, M; Trichard, L; Grossiord, J-L; Chaminade, P; Duchêne, D; Le Bas, G; Fattal, E; Bochot, A

    2009-11-01

    Natural cyclodextrins are cyclic oligosaccharides which can be modified to obtain more water soluble or insoluble derivatives. The main interest of cyclodextrins results from their ability to form an inclusion complex with hydrophobic molecules. Inclusion constitutes a true molecular encapsulation. This property is employed in pharmaceutical industry to facilitate the formulation of poorly water soluble and/or fragile drugs. A more recent application of cyclodextrins consists in their use in the preparation of dispersed systems such as micro- and nanoparticles or even liposomes. When incorporated in dispersed systems, cyclodextrin can enhance drug solubility, drug stability and drug loading. Interestingly, cyclodextrins themselves can also be employed to form or stabilise dispersed systems (material or emulsifying agent). For example, the interactions between cyclodextrins with components of the vegetable oils (more especially with triglycerides) allow to stabilise simple or multiple emulsions but also to form particles called "beads". Very rich in oil, this novel lipid carrier presents an important potential for the encapsulation of highly lipophilic compounds and their delivery by topical and oral routes. These two applications are more particularly developed in the present paper.

  10. Spruce galactoglucomannans inhibit the lipid oxidation in rapeseed oil-in-water emulsions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oil-in-water emulsions are functional and industrially valuable systems, whose large interfacial area makes them prone to deterioration, due in part to as the oxidation and oligomerization of polyunsaturated fatty acids. Spruce galactoglucomannans (GGM), wood biomacromolecules abundantly available f...

  11. Effects of metal chelator, sodium azide, and superoxide dismutase on the oxidative stability in riboflavin-photosensitized oil-in-water emulsion systems.

    PubMed

    Lee, JaeHwan; Decker, Eric A

    2011-06-08

    The effects of riboflavin photosensitization on the oxidative stability of oil-in-water (O/W) emulsions were determined using lipid hydroperoxides and headspace volatile analyses. The influences of a metal chelator, sodium azide, and superoxide dismutase (SOD) on oxidation pathways were tested to gain a better understanding of the role of transition metals, singlet oxygen, and superoxide anion, respectively. Emulsions with riboflavin and visible light irradiation had significantly higher lipid hydroperoxides and volatiles (p < 0.05) as compared to samples without light irradiation or riboflavin. The addition of ethylenediammetetraacetic acid (EDTA) decreased the formation of lipid hydroperoxides, hexanal, 2-heptenal, and 1-octen-3-ol in a concentration-dependent manner. Sodium azide, a singlet oxygen physical quencher, only inhibited the formation of 2-heptenal and 1-octen-3-ol. Overall, photosensitized riboflavin participated in both type I and type II pathways in O/W emulsions, and these pathways enhance the prooxidant activity of metals through their ability to produce lipid hydroperoxides and superoxide anion.

  12. Effects of parenteral infusion with medium-chain triglycerides and safflower oil emulsions on hepatic lipids, plasma amino acids and inflammatory mediators in septic rats.

    PubMed

    Yeh, S; Chao, C; Lin, M; Chen, W

    2000-04-01

    This study was designed to investigate the effects of preinfusion with total parenteral nutrition (TPN) using medium-chain triglycerides (MCT) versus safflower oil (SO) emulsion as fat sources on hepatic lipids, plasma amino acid profiles, and inflammatory-related mediators in septic rats. Normal rats, with internal jugular catheters, were divided into two groups and received TPN. TPN provided 300kcal/kg/day with 40% of the non-protein energy provided as fat. All TPN solutions were isonitrogenous and identical in nutrient composition except for the fat emulsion, which was made of SO or a mixture of MCT and soybean oil (9:1) (MO). After receiving TPN for 6 days, each group of rats was further divided into control and sepsis subgroups. Sepsis was induced by cecal ligation and puncture, whereas control rats received sham operation. All rats were classified into four groups as follows: MCT control group (MOC, n= 8), MCT sepsis group (MOS, n= 8), safflower oil control group (SOC, n= 8), and safflower oil sepsis group (SOS, n= 11). The results of the study demonstrated that the MOS group had lower hepatic lipids than did the SOS group. Plasma leucine and isoleucine levels were significantly lower in the SOS than in the SOC group, but no differences in these two amino acids were observed between the MOC and MOS groups. Plasma arginine levels were significantly lower in septic groups than in those without sepsis despite whether MCT or safflower oil was infused. Plasma glutamine and alanine levels, however, did not differ between septic and non-septic groups either in the SO or MO groups. No differences in interleukin-1b, interleukin-6, tumor necrosis factor-alpha, and leukotriene B(4)concentrations in peritoneal lavage fluid were observed between the two septic groups. These results suggest that catabolic reaction is septic rats preinfused MCT is not as obvious as those preinfused safflower oil. Compared with safflower oil, TPN with MCT administration has better effects on

  13. Water in Oil Emulsions: A New System for Assembling Water-soluble Chlorophyll-binding Proteins with Hydrophobic Pigments.

    PubMed

    Bednarczyk, Dominika; Noy, Dror

    2016-03-21

    Chlorophylls (Chls) and bacteriochlorophylls (BChls) are the primary cofactors that carry out photosynthetic light harvesting and electron transport. Their functionality critically depends on their specific organization within large and elaborate multisubunit transmembrane protein complexes. In order to understand at the molecular level how these complexes facilitate solar energy conversion, it is essential to understand protein-pigment, and pigment-pigment interactions, and their effect on excited dynamics. One way of gaining such understanding is by constructing and studying complexes of Chls with simple water-soluble recombinant proteins. However, incorporating the lipophilic Chls and BChls into water-soluble proteins is difficult. Moreover, there is no general method, which could be used for assembly of water-soluble proteins with hydrophobic pigments. Here, we demonstrate a simple and high throughput system based on water-in-oil emulsions, which enables assembly of water-soluble proteins with hydrophobic Chls. The new method was validated by assembling recombinant versions of the water-soluble chlorophyll binding protein of Brassicaceae plants (WSCP) with Chl a. We demonstrate the successful assembly of Chl a using crude lysates of WSCP expressing E. coli cell, which may be used for developing a genetic screen system for novel water-soluble Chl-binding proteins, and for studies of Chl-protein interactions and assembly processes.

  14. Reversed phase HPLC analysis of stability and microstructural effects on degradation kinetics of β-carotene encapsulated in freeze-dried maltodextrin-emulsion systems.

    PubMed

    Harnkarnsujarit, Nathdanai; Charoenrein, Sanguansri; Roos, Yrjö H

    2012-09-26

    Degradation of dispersed lipophilic compounds in hydrophilic solids depends upon matrix stability and lipid physicochemical properties. This study investigated effects of solid microstructure and size of lipid droplets on the stability of dispersed β-carotene in freeze-dried systems. Emulsions of β-carotene in sunflower oil were dispersed in maltodextrin systems (M040/DE6, M100/DE11, and M250/DE25.5) (8% w/w oil) and prefrozen at various freezing conditions prior to freeze-drying to control nucleation and subsequent pore size and structural collapse of freeze-dried solids. The particle size, physical state, and β-carotene contents of freeze-dried emulsions were measured during storage at various water activity (a(w)) using a laser particle size analyzer, differential scanning calorimeter, and high performance liquid chromatography (HPLC), respectively. The results showed that M040 stabilized emulsions in low temperature freezing exhibited lipid crystallization. Collapse of solids in storage at a(w) which plasticized systems to the rubbery state led to flow and increased the size of oil droplets. Degradation of β-carotene analyzed using a reversed-phase C(30) column followed first-order kinetics. Porosity of solids had a major effect on β-carotene stability; however, the highest stability was found in fully plasticized and collapsed solids.

  15. Surface-active properties of lipophilic antioxidants tyrosol and hydroxytyrosol fatty acid esters: a potential explanation for the nonlinear hypothesis of the antioxidant activity in oil-in-water emulsions.

    PubMed

    Lucas, Ricardo; Comelles, Francisco; Alcántara, David; Maldonado, Olivia S; Curcuroze, Melanie; Parra, Jose L; Morales, Juan C

    2010-07-14

    Our group has recently observed a nonlinear tendency in antioxidant capacity of different hydroxytyrosol fatty acid esters in fish oil-in-water emulsions, where a maximum of antioxidant efficiency appeared for hydroxytyrosol octanoate. These results appear to disagree with the antioxidant polar paradox. Because the physical location of the antioxidants in an oil-water interface has been postulated as an important factor in explaining this behavior, we have prepared a series of tyrosol and hydroxytyrosol fatty acid esters with different chain length and studied their surface-active properties in water, because these physicochemical parameters could be directly related to the preferential placement at the interface. We have found that tyrosol and hydroxytyrosol fatty acid esters are relevant surfactants when the right hydrophilic-lipophilic balance (HLB) is attained and, in some cases, as efficient as emulsifiers commonly used in industry, such as Brij 30 or Tween 20. Moreover, a nonlinear dependency of surfactant effectiveness is observed with the increase in chain length of the lipophilic antioxidants. This tendency seems to fit quite well with the reported antioxidant activity in emulsions, and the best antioxidant of the series (hydroxytyrosol octanoate) is also a very effective surfactant. This potential explanation of the nonlinear hypothesis will help in the rational design of antioxidants used in oil-in-water emulsions.

  16. Hexagonal phase based gel-emulsion (O/H1 gel-emulsion): formation and rheology.

    PubMed

    Alam, Mohammad Mydul; Aramaki, Kenji

    2008-11-04

    The formation, stability, and rheological behavior of a hexagonal phase based gel-emulsion (O/H1 gel-emulsion) have been studied in water/C12EO8/hydrocarbon oil systems. A partial phase behavior study indicates that the oil nature has no effect on the phase sequences in the ternary phase diagram of water/C12EO8/oil systems but the domain size of the phases or the oil solubilization capacity considerably changes with oil nature. Excess oil is in equilibrium with the hexagonal phase (H1) in the ternary phase diagram in the H1+O region. The O/H1 gel-emulsion was prepared (formation) and kept at 25 degrees C to check stability. It has been found that the formation and stability of the O/H1 gel-emulsion depends on the oil nature. After 2 min observation (formation), the results show that short chain linear hydrocarbon oils (heptane, octane) are more apt to form a O/H1 gel-emulsion compared to long chain linear hydrocarbon oils (tetradecane, hexadecane), though the stability is not good enough in either system, that is, oil separates within 24 h. Nevertheless, the formation and stability of the O/H1 gel-emulsion is appreciably increased in squalane and liquid paraffin. It is surmised that the high transition temperature of the H1+O phase and the presence of a bicontinuous cubic phase (V1) might hamper the formation of a gel-emulsion. It has been pointed out that the solubilization of oil in the H1 phase could be related to emulsion stability. On the other hand, the oil nature has little or no effect on the formation and stability of a cubic phase based gel-emulsion (O/I1 gel-emulsion). From rheological measurements, it has found that the rheogram of the O/H1 gel-emulsion indicates gel-type structure and shows shear thinning behavior similar to the case of the O/I1 gel-emulsion. Rheological data infer that the O/I1 gel-emulsion is more viscous than the O/H1 gel-emulsion at room temperature but the O/H1 gel-emulsion shows consistency at elevated temperature.

  17. Effect of pectins on the mass transfer kinetics of monosaccharides, amino acids, and a corn oil-in-water emulsion in a Franz diffusion cell.

    PubMed

    Espinal-Ruiz, Mauricio; Restrepo-Sánchez, Luz-Patricia; Narváez-Cuenca, Carlos-Eduardo

    2016-10-15

    The effect of high (HMP) and low (LMP) methoxylated pectins (2%w/w) on the rate and extent of the mass transfer of monosaccharides, amino acids, and a corn oil-in-water emulsion across a cellulose membrane was evaluated. A sigmoidal response kinetic analysis was used to calculate both the diffusion coefficients (rate) and the amount of nutrients transferred through the membrane (extent). In all cases, except for lysine, HMP was more effective than LMP in inhibiting both the rate and extent of the mass transfer of nutrients through the membrane. LMP and HMP, e.g., reduced 1.3 and 3.0times, respectively, the mass transfer rate of glucose, as compared to control (containing no pectin), and 1.3 and 1.5times, respectively, the amount of glucose transferred through the membrane. Viscosity, molecular interactions, and flocculation were the most important parameters controlling the mass transfer of electrically neutral nutrients, electrically charged nutrients, and emulsified lipids, respectively.

  18. Impact of electrolytes on double emulsion systems (W/O/W) stabilized by an amphiphilic block copolymer.

    PubMed

    Zhang, Yu; Gou, Jingxin; Sun, Feng; Geng, SiCong; Hu, Xi; Zhang, Keru; Lin, Xia; Xiao, Wei; Tang, Xing

    2014-10-01

    In this work, the block copolypeptide surfactant, poly(l-lysine·HBr)40-b-poly(racemic-leucine)20, was synthesized and characterized, then used to build water-in-oil-in-water (W/O/W) double emulsions. Double emulsions are usually prepared by a two-step emulsification process and commonly stabilized using a combination of hydrophilic and hydrophobic surfactants. Herein, we report a one-step phase inversion process to produce water-in-oil-in-water (W/O/W) double emulsions stabilized by a synthetic diblock copolymer and electrolyte. It was found that the O/W ratio and the type of electrolyte had a marked effect on the formation and type of the double emulsions. Moreover, double emulsions containing an NaCl isotonic solution were stable for at least two months, whereas those using glucose as a substitute for NaCl showed a clear compartmental change. The mechanism behind this was related to the electrostatic interaction between the anion of the electrolyte and the cation of the polylysine residues, which affected the HLB value and curvature. This novel finding is very interesting in terms of both scientific research and practical applications.

  19. Latest Developments in Nuclear Emulsion Technology

    NASA Astrophysics Data System (ADS)

    Morishima, Kunihiro

    Nuclear emulsion is high sensitive photographic film used for detection of three-dimensional trajectory of charged particles. These trajectories are recorded as tracks consist of a lot of silver grains. The size of silver grain is about 1 μm, so that nuclear emulsion has submicron three-dimensional spatial resolution, which gives us a few mrad three-dimensional angular resolution. The important technical progress was speed-up of the read-out technique of nuclear emulsions built with optical microscope system. We succeeded in developing a high-speed three-dimensional read-out system named Super Ultra Track Selector (S-UTS) with the operating read-out speed of approximately 50 cm2/h. Nowadays we are developing the nuclear emulsion gel independently in Nagoya University by introducing emulsion gel production machine. Moreover, we are developing nuclear emulsion production technologies (gel production, poring and mass production). In this paper, development of nuclear emulsion technologies for the OPERA experiment, applications by the technologies and current development are described.

  20. High acyl gellan as an emulsion stabilizer.

    PubMed

    Vilela, Joice Aline Pires; da Cunha, Rosiane Lopes

    2016-03-30

    High acyl gellan (0.01-0.2% w/w) was used as stabilizer in oil in water emulsions containing 30% (w/w) of sunflower oil and prepared under different process conditions. Stable emulsions to phase separation could be obtained using high acyl gellan (HA) content above 0.05% (w/w), while low acyl gellan (LA) prepared at the same conditions could not stabilize emulsions. Emulsions properties depended on the process used to mix the oil and gellan dispersion since high pressure homogenization favored stabilization while very high energy density applied by ultrasound led to systems destabilization. Emulsions prepared using high pressure homogenization showed zeta potential values ranging from -50 up to -59 mV, suggesting that electrostatic repulsion could be contributing to the systems stability. Rheological properties of continuous phase were also responsible for emulsions stabilization, since HA gellan dispersions showed high viscosity and gel-like behavior. The high viscosity of the continuous phase could be associated to the presence of high acyl gellan microgels/aggregates. Disentanglement of these aggregates performed by ultrasound strongly decreased the viscosity and consequently affected the emulsions behavior, reducing the stability to phase separation.

  1. The olive oil-based lipid clinoleic blocks leukocyte recruitment and improves survival during systemic inflammation: a comparative in vivo study of different parenteral lipid emulsions.

    PubMed

    Buschmann, Kirsten; Poeschl, Johannes; Braach, Natascha; Hudalla, Hannes; Kuss, Navina; Frommhold, David

    2015-01-01

    Although fish oil-based and olive oil-based lipid emulsions have been shown to exert anti-inflammatory functions, the immunomodulating properties of lipids are still controversial. Therefore, we investigated the anti-inflammatory effect of three different parenterally administered lipid emulsions in vivo: olive oil-based Clinoleic, fish oil-based Smoflipid, and soybean oil-based Lipofundin. We observed leukocyte recruitment in inflamed murine cremaster muscle using intravital microscopy and survival in a murine model of LPS-induced systemic inflammation and analyzed expression of leukocyte and endothelial adhesion molecules. Olive oil-based Clinoleic and fish oil-based Smoflipid profoundly inhibited leukocyte adhesion compared to Lipofundin during LPS-induced inflammation of the murine cremaster muscle. In the trauma model of cremaster muscle inflammation, Lipofundin was the only lipid emulsion that even augmented leukocyte adhesion. In contrast to Smoflipid and Lipofundin, Clinoleic effectively blocked leukocyte recruitment and increased survival during lethal endotoxemia. Flow chamber experiments and analysis of adhesion molecule expression suggest that both endothelial and leukocyte driven mechanisms might contribute to anti-inflammatory effects of Clinoleic. We conclude that the anti-inflammatory properties of Clinoleic are superior to those of Smoflipid and Lipofundin even during systemic inflammation. Thus, these results should stimulate further studies investigating parenteral lipids as an anti-inflammatory strategy in critically ill patients.

  2. Oil emulsions of fluorosilicone fluids

    SciTech Connect

    Keil, J. W.

    1985-08-27

    Emulsions of fluorosilicone fluids in mineral oil are disclosed. These emulsions are stabilized by a polydimethylsiloxane-polybutadiene copolymer or a polydimethylsiloxane-hydrogenated polybutadiene copplymer. The emulsions are an effective foam suppressant for organic liquids, especially crude petroleum.

  3. Influence of whey protein-beet pectin conjugate on the properties and digestibility of β-carotene emulsion during in vitro digestion.

    PubMed

    Xu, Duoxia; Yuan, Fang; Gao, Yanxiang; Panya, Atikorn; McClements, David Julian; Decker, Eric Andrew

    2014-08-01

    The impact of a whey protein isolate (WPI)-beet pectin (BP) conjugate (formed by dry-heating) on the physical properties and digestibilities of β-carotene and carrier oil in oil-in-water emulsions was studied when they passed through a model gastrointestinal system. β-Carotene emulsions were stabilized by WPI, unconjugated and conjugated WPI-BP, separately. The emulsions were then passed through an in vitro digestion model and the mean droplet size, droplet distribution, zeta-potential, free fatty acids and β-carotene released were measured. The stability to droplet flocculation and coalescence during digestion was increased for the WPI-BP conjugate stabilized emulsion. Addition of BP onto the WPI stabilized emulsions could inhibit the releases of carrier oil (MCT) and β-carotene. The releases of free fatty acids and β-carotene did not differ greatly between the unconjugated and conjugated WPI-BP stabilized emulsions. These results have important implications for protein-polysaccharide stabilized emulsions and conjugates used for the protection and delivery of bioactive compounds.

  4. Pump safety tests regarding emulsion explosives

    SciTech Connect

    Perlid, H.

    1996-12-31

    In the handling of emulsion explosives pumping is a key operation. A number of serious accidents has shown that pumping can be a risky operation and should be carefully considered and investigated. This is the background behind a series of pump tests carried out by Nitro Nobel. This paper refers to pump safety tests with an eccentric screw pump (progressive cavity) and emulsion explosives. A selection of emulsions unsensitized as well as sensitized were tested. The tests were performed in a circulation system against dead head and as dry pumping.

  5. Effects of lactoferrin, phytic acid, and EDTA on oxidation in two food emulsions enriched with long-chain polyunsaturated fatty acids.

    PubMed

    Nielsen, Nina S; Petersen, Arni; Meyer, Anne S; Timm-Heinrich, Maike; Jacobsen, Charlotte

    2004-12-15

    The influence of the addition of metal chelators on oxidative stability was studied in a milk drink and in a mayonnaise system containing highly polyunsaturated lipids. Milk drinks containing 5% (w/w) of specific structured lipid were supplemented with lactoferrin (6-24 muM) and stored at 2 degrees C for up to 9 weeks. Mayonnaise samples with 16% fish oil and 64% rapeseed oil (w/w) were supplemented with either lactoferrin (8-32 muM), phytic acid (16-124 muM), or EDTA (16-64 muM) and were stored at 20 degrees C for up to 4 weeks. The effect of the metal chelators was evaluated by determination of peroxide values, secondary volatile oxidation products, and sensory analysis. Lactoferrin reduced the oxidation when added in concentrations of 12 muM in the milk drink and 8 muM in the mayonnaise, whereas it was a prooxidant at higher concentrations in both systems. In mayonnaise, EDTA was an effective metal chelator even at 16 muM, whereas phytic acid did not exert a distinct protective effect against oxidation. The differences in the equimolar effects of the metal chelators are proposed to be due to differences in their binding constants to iron and their different stabilities toward heat and low pH.

  6. Impact of extra virgin olive oil and ethylenediaminetetraacetic acid (EDTA) on the oxidative stability of fish oil emulsions and spray-dried microcapsules stabilized by sugar beet pectin.

    PubMed

    Polavarapu, Sudheera; Oliver, Christine M; Ajlouni, Said; Augustin, Mary Ann

    2012-01-11

    The influence of EDTA on lipid oxidation in sugar beet pectin-stabilized oil-in-water emulsions (pH 6, 15% oil, wet basis), prepared from fish oil (FO) and fish oil-extra virgin olive oil (FO-EVOO) (1:1 w/w), as well as the spray-dried microcapsules (50% oil, dry basis) prepared from these emulsions, was investigated. Under accelerated conditions (80 °C, 5 bar oxygen pressure) the oxidative stability was significantly (P < 0.05) higher for FO and FO-EVOO formulated with EDTA, in comparison to corresponding emulsions and spray-dried microcapsules formulated without EDTA. The EDTA effect was greater in emulsions than in spray-dried microcapsules, with the greatest protective effect obtained in FO-EVOO emulsions. EDTA enhanced the oxidative stability of the spray-dried microcapsules during ambient storage (~25 °C, a(w) = 0.5), as demonstrated by their lower concentration of headspace volatile oxidation products, propanal and hexanal. These results show that the addition of EDTA is an effective strategy to maximize the oxidative stability of both FO emulsions and spray-dried microcapsules in which sugar beet pectin is used as the encapsulant material.

  7. Smart magnetic ionic liquid-based Pickering emulsions stabilized by amphiphilic Fe3O4 nanoparticles: Highly efficient extraction systems for water purification.

    PubMed

    Yang, Huirong; Zhang, Hongxia; Peng, Junxia; Zhang, Yuanyuan; Du, Guanqun; Fang, Yu

    2017-01-01

    This study presents the general method to formulate magnetically responsive ionic liquid (IL)-based Pickering emulsions that are stabilized by amphiphilic Fe3O4 nanoparticles. The magnetic nanoparticle stabilizer (MN-CHOL) was synthesized using the surface-initiated ATRP method with further modification that uses a specially designed cholesteryl derivative, and characterized by FT-IR, XPS, TGA, and magnetization measurements. It is confirmed that the resulting MN-CHOL shows a stronger interfacial activity, efficiently emulsifying C4mim [PF6] and water, and resultantly forming stable Pickering emulsions without the help of any co-surfactant. Due to its super paramagnetism and high saturation magnetization, MN-CHOL attached on the IL interface enables droplets of IL to be moved very conveniently on their target for as many times by an external magnetic field without demulsification, indicating high controllability and excellent stability. The resulting Pickering emulsion is a good extraction system that efficiently separates chlorobenzene, phenol, and methyl orange from aqueous solution. Subsequently, the simple magnetic separation was applied, to produce purified water due as a result of the rapid removal of organic pollutants from contaminated water.

  8. Integrated pulsed holography system for mastering and transferring onto AGFA or VR-P emulsions

    NASA Astrophysics Data System (ADS)

    Grichine, Mikhail V.; Ratcliffe, David B.; Skokov, Gleb R.

    1998-02-01

    It has been traditionally accepted that the beam parameters of pulsed lasers permit their use in mastering but are less easily applied to image-transferring. Using an innovative optical scheme and appropriate chemistry we have demonstrated a simple easy-to-use system based on a Nd:YLF/phosphate glass laser that may be used both for mastering and for the production of the final large or small-format white-light viewable (wlv) hologram. We have tested this system on both the AGFA 8E56 and the Russian VR- P plates and films. On both materials we are able to obtain identical qualities in every way equivalent to CW work and with many advantages. In addition we present several color control systems that allow adequate flexibility in the color of the final wlv reflection hologram.

  9. Phase Behavior of Dilute Carbon Black Suspensions and Carbon Black Stabilized Emulsions

    NASA Astrophysics Data System (ADS)

    Godfrin, Michael; Tiwari, Ayush; Bose, Arijit; Tripathi, Anubhav

    2014-11-01

    We use para-amino benzoic acid terminated carbon black (CB) as a tunable model particulate material to study the effect of inter-particle interactions on phase behavior and steady shear stresses in suspensions and particle-stabilized emulsions. We modulate inter-particle interactions by adding NaCl to the suspension, thus salting surface carboxylate groups. Surprisingly, yield stress behavior emerged at a volume fraction of CB as low as ϕCB = 0.008, and gel behavior was observed at ϕCB >0.05, well below the percolation threshold for non-interacting particles. The yield stress was found to grow rapidly with carbon black concentration suggesting that salt-induced hydrophobicity leads to strong inter-particle interactions and the formation of a network at low particle concentrations. The yield stresses of CB-stabilized emulsions also grows rapidly with carbon black concentrations, implying that inter-droplet interactions can be induced through the tuning of carbon black concentration in emulsion systems. Emulsions stabilized by ionic surfactants show no inter-droplet interactions. In contrast, oil droplets in the CB-stabilized emulsion move collectively or are immobilized because of an interconnected CB network in the aqueous phase.

  10. Multi-body coalescence in Pickering emulsions.

    PubMed

    Wu, Tong; Wang, Haitao; Jing, Benxin; Liu, Fang; Burns, Peter C; Na, Chongzheng

    2015-01-12

    Particle-stabilized Pickering emulsions have shown unusual behaviours such as the formation of non-spherical droplets and the sudden halt of coalescence between individual droplets. Here we report another unusual behaviour of Pickering emulsions-the simultaneous coalescence of multiple droplets in a single event. Using latex particles, silica particles and carbon nanotubes as model stabilizers, we show that multi-body coalescence can occur in both water-in-oil and oil-in-water emulsions. The number of droplets involved in the nth coalscence event equals four times the corresponding number of the tetrahedral sequence in close packing. Furthermore, coalescence is promoted by repulsive latex and silica particles but inhibited by attractive carbon nanotubes. The revelation of multi-body coalescence is expected to help better understand Pickering emulsions in natural systems and improve their designs in engineering applications.

  11. An exclusively based parenteral fish-oil emulsion reverses cholestasis.

    PubMed

    Triana Junco, Miryam; García Vázquez, Natalia; Zozaya, Carlos; Ybarra Zabala, Marta; Abrams, Steven; García de Lorenzo, Abelardo; Sáenz de Pipaón Marcos, Miguel

    2014-10-25

    Prolonged parenteral nutrition (PN) leads to liver damage. Recent interest has focused on the lipid component of PN. A lipid emulsion based on w-3 fatty acids decrease conjugated bilirubin. A mixed lipid emulsion derived from soybean, coconut, olive, and fish oils reverses jaundice. Here we report the reversal of cholestasis and the improvement of enteral feeding tolerance in 1 infant with intestinal failure-associated liver disease. Treatment involved the substitution of a mixed lipid emulsion with one containing primarily omega-3 fatty acids during 37 days. Growth and biochemical tests of liver function improved significantly. This suggests that fat emulsions made from fish oils may be more effective means of treating this condition compared with an intravenous lipid emulsion containing soybean oil, medium -chain triglycerides, olive oil, and fish oil.

  12. Effect of emulsifier on oxidation properties of fish oil-based structured lipid emulsions.

    PubMed

    Fomuso, Lydia B; Corredig, Milena; Akoh, Casimir C

    2002-05-08

    The effects of the emulsifiers lecithin, Tween 20, whey protein isolate, mono-/diacylglycerols, and sucrose fatty acid ester on oxidation stability of a model oil-in-water emulsion prepared with enzymatically synthesized menhaden oil-caprylic acid structured lipid were evaluated. Oxidation was monitored by measuring lipid hydroperoxides, thiobarbituric acid reactive substances, and the ratio of combined docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) contents to palmitic acid in the emulsion. After high-pressure homogenization, all emulsions, except those prepared with lecithin, had similar droplet size distributions. All structured lipid emulsions, except for the lecithin-stabilized emulsions, were stable to creaming over the 48-day period studied. Emulsifier type and concentration affected oxidation rate, with 0.25% emulsifier concentration generally having a higher oxidation rate than 1% emulsifier concentration. Overall, oxidation did not progress significantly enough in 48 days of storage to affect DHA and EPA levels in the emulsion.

  13. Rapid and medium setting high float bituminous emulsions

    SciTech Connect

    Schilling, P.; Schreuders, H.G.

    1987-06-30

    This patent describes a rapid set high float aqueous bituminous emulsion-comprising bitumen, water, and from about 0.4% to about 0.6%, based on the weight of the emulsion, of an anionic emulsifier comprised of an alkaline solution of a combination of (1) 20% to 80% fatty acids selected from the group consisting of tall oil fatty acids, tallow fatty acids, and mixtures. (2) 20% to 80% of a product of the reaction of the fatty acids with a member of the group consists of acrylic acid, methacrylic acid, fumaric acid, and maleic anhydride.

  14. Physical and antimicrobial properties of thyme oil emulsions stabilized by ovalbumin and gum arabic.

    PubMed

    Niu, Fuge; Pan, Weichun; Su, Yujie; Yang, Yanjun

    2016-12-01

    Natural biopolymer stabilized oil-in-water emulsions were formulated using ovalbumin (OVA), gum arabic (GA) solutions and their complexes. The influence of interfacial structure of emulsion (OVA-GA bilayer and OVA/GA complexes emulsions) on the physical properties and antimicrobial activity of thyme oil (TO) emulsion against Escherichia coli (E. coli) was evaluated. The results revealed that the two types of emulsions with different oil phase compositions remained stable during a long storage period. The oil phase composition had an appreciable influence on the mean particle diameter and retention of the TO emulsions. The stable emulsion showed a higher minimum inhibitory concentration (MIC), and the TO emulsions showed an improved long-term antimicrobial activity compared to the pure thyme oil, especially complexes emulsion at pH 4.0. These results provided useful information for developing protection and delivery systems for essential oil using biopolymer.

  15. Cerebral Microvascular and Systemic Effects Following Intravenous Administration of the Perfluorocarbon Emulsion Perftoran

    PubMed Central

    Abutarboush, Rania; Saha, Biswajit K.; Mullah, Saad H.; Arnaud, Francoise G.; Haque, Ashraful; Aligbe, Chioma; Pappas, Georgina; Auker, Charles R.; McCarron, Richard M.; Moon-Massat, Paula F.; Scultetus, Anke H.

    2016-01-01

    Oxygen-carrying perfluorocarbon (PFC) fluids have the potential to increase tissue oxygenation during hypoxic states and to reduce ischemic cell death. Regulatory approval of oxygen therapeutics was halted due to concerns over vasoconstrictive side effects. The goal of this study was to assess the potential vasoactive properties of Perftoran by measuring brain pial arteriolar diameters in a healthy rat model. Perftoran, crystalloid (saline) or colloid (Hextend) solutions were administered as four sequential 30 min intravenous (IV) infusions, thus allowing an evaluation of cumulative dose-dependent effects. There were no overall changes in diameters of small-sized (<50 μm) pial arterioles within the Perftoran group, while both saline and Hextend groups exhibited vasoconstriction. Medium-sized arterioles (50–100 μm) showed minor (~8–9%) vasoconstriction within saline and Hextend groups and only ~5% vasoconstriction within the Perftoran group. For small- and medium-sized pial arterioles, the mean percent change in vessel diameters was not different among the groups. Although there was a tendency for arterial blood pressures to increase with Perftoran, pressures were not different from the other two groups. These data show that Perftoran, when administered to healthy anesthetized rats, does not cause additional vasoconstriction in cerebral pial arterioles or increase systemic blood pressure compared with saline or Hextend. PMID:27869709

  16. Conditions for equilibrium solid-stabilized emulsions.

    PubMed

    Kraft, Daniela J; de Folter, Julius W J; Luigjes, Bob; Castillo, Sonja I R; Sacanna, Stefano; Philipse, Albert P; Kegel, Willem K

    2010-08-19

    Particular types of solid-stabilized emulsions can be thermodynamically stable as evidenced by their spontaneous formation and monodisperse droplet size, which only depends on system parameters. Here, we investigate the generality of these equilibrium solid-stabilized emulsions with respect to the basic constituents: aqueous phase with ions, oil, and stabilizing particles. From systematic variations of these constituents, we identify general conditions for the spontaneous formation of monodisperse solid-stabilized emulsions droplets. We conclude that emulsion stability is achieved by a combination of solid particles as well as amphiphilic ions adsorbed at the droplet surface, and low interfacial tensions of the bare oil-water interface of order 10 mN/m or below. Furthermore, preferential wetting of the colloidal particles by the oil phase is necessary for thermodynamic stability. We demonstrate the sufficiency of these basic requirements by extending the observed thermodynamic stability to emulsions of different compositions. Our findings point to a new class of colloid-stabilized meso-emulsions with a potentially high impact on industrial emulsification processes due to the associated large energy savings.

  17. Evaluation on oxidative stability of walnut beverage emulsions.

    PubMed

    Liu, Shuang; Liu, Fuguo; Xue, Yanhui; Gao, Yanxiang

    2016-07-15

    Walnut beverage emulsions were prepared with walnut kernels, mixed nonionic emulsifiers and xanthan gum. The effects of food antioxidants on the physical stability and lipid oxidation of walnut beverage emulsions were investigated. The results showed that tea polyphenols could not only increase the droplet size of the emulsions, but also enhance physical stability during the thermal storage at 62 ± 1 °C. However, water-dispersed oil-soluble vitamin E and enzymatically modified isoquercitrin obviously decreased the physical stability of the emulsion system during the thermal storage. BHT and natural antioxidant extract had scarcely influenced on the physical stability of walnut beverage emulsions. Tea polyphenols and BHT could significantly retard lipid oxidation in walnut beverage emulsions against thermal and UV light exposure during the storage. Vitamin E exhibited the prooxidant effect during the thermal storage and the antioxidant attribute during UV light exposure. Other food antioxidants had no significant effect on retarding lipid oxidation during thermal or light storage.

  18. Use of an omega-3 fatty acid-based emulsion in the treatment of parenteral nutrition-induced cholestasis in patients with microvillous inclusion disease.

    PubMed

    Fuchs, Julie; Fallon, Erica M; Gura, Kathleen M; Puder, Mark

    2011-12-01

    Microvillous inclusion disease is a congenital intestinal epithelial cell disorder leading to lifelong intestinal failure. In this report, we discuss the use of a fish oil-based lipid emulsion in the treatment of 3 patients with microvillous inclusion disease who developed parenteral nutrition-associated liver disease.

  19. Development of food-grade nanoemulsions and emulsions for delivery of omega-3 fatty acids: opportunities and obstacles in the food industry.

    PubMed

    Walker, Rebecca; Decker, Eric A; McClements, David Julian

    2015-01-01

    Consumption of biologically active amounts of omega-3 fatty acids is linked to improved human health, which has partly been attributed to their important role in brain development and cardiovascular health. Western diets are relatively low in omega-3 fatty acids and many consumers turn to supplements or functional foods to increase their intake of these healthy lipids. Fish oil is one of the most widely used sources of omega-3 fatty acid for supplementation and has greater health benefits than plant sources because of its higher concentration of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The incorporation of omega-3 fatty acids into foods and beverages is often challenging due to their low water-solubility, poor oxidative stability, and variable bioavailability. Nanoemulsions offer a promising way to incorporate omega-3 fatty acids into liquid food systems like beverages, dressing, sauces, and dips. Nanoemulsions are colloidal dispersions that contain small oil droplets (r<100 nm) that may be able to overcome many of the challenges of fortifying foods and beverages with omega-3 fatty acids. The composition and fabrication of nanoemulsions can be optimized to increase the chemical and physical stability of oil droplets, as well as to increase the bioavailability of omega-3 fatty acids.

  20. Nucleic acid based logical systems.

    PubMed

    Han, Da; Kang, Huaizhi; Zhang, Tao; Wu, Cuichen; Zhou, Cuisong; You, Mingxu; Chen, Zhuo; Zhang, Xiaobing; Tan, Weihong

    2014-05-12

    Researchers increasingly visualize a significant role for artificial biochemical logical systems in biological engineering, much like digital logic circuits in electrical engineering. Those logical systems could be utilized as a type of servomechanism to control nanodevices in vitro, monitor chemical reactions in situ, or regulate gene expression in vivo. Nucleic acids (NA), as carriers of genetic information with well-regulated and predictable structures, are promising materials for the design and engineering of biochemical circuits. A number of logical devices based on nucleic acids (NA) have been designed to handle various processes for technological or biotechnological purposes. This article focuses on the most recent and important developments in NA-based logical devices and their evolution from in vitro, through cellular, even towards in vivo biological applications.

  1. Development of Nuclear Emulsion for Fast Neutron Measurement

    NASA Astrophysics Data System (ADS)

    Machii, Shogo; Kuwabara, Kenichi; Morishima, Kunihiro

    Nuclear emulsion is high sensitive photographic film used for detection of three-dimensional trajectory of charged particles. Energy resolution of nuclear emulsion is 21% (12%) FWHM against neutron energy of 2.8 MeV (4.9 MeV). Nuclear emulsion has high gamma ray rejection power. For now, at least 2×104 gamma rays/cm2, no increase of as a background for neutron measurement when scan using automatic nuclear emulsion read out system HTS. This value suggests that it is applicable even under high gamma ray environment, such as nuclear fusion reactor.

  2. Boric Acid Reclamation System (BARS)

    SciTech Connect

    Kniazewycz, B.G.; Markind, J.

    1986-03-01

    KLM Technologies' personnel have identified a Boric Acid Reclamation System (BARS) utilizing reverse osmosis and ultrafiltration to produce a recyclable grade of otherwise waste boric acid at PWRs, thus reducing a major source of low-level radwaste. The design of a prototype BARS as a compact volume reduction system was the result of KLM's Phase 1 Program, and based upon a preliminary feasibility program, which assessed the applicability of membrane technology to refurbish and recycle waste boric acid from floor and equipment drain streams. The analysis of the overall program indicated a substantial savings regarding off-site disposal costs. Today's economic scenario indicates that optimization of volume reduction operation procedures could significantly reduce waste management costs, especially where burial penalties have become more severe. As a reaction to the economic burden imposed by final disposal, many nuclear plants are currently modifying their design and operating philosophies concerning liquid radwaste processing systems to meet stricter environmental regulations, and to derive potential economic benefits by reducing the ever-increasing volumes of wastes that are produced. To effect these changes, innovative practices in waste management and more efficient processing technologies are being successfully implemented.

  3. Pickering emulsions for skin decontamination.

    PubMed

    Salerno, Alicia; Bolzinger, Marie-Alexandrine; Rolland, Pauline; Chevalier, Yves; Josse, Denis; Briançon, Stéphanie

    2016-08-01

    This study aimed at developing innovative systems for skin decontamination. Pickering emulsions, i.e. solid-stabilized emulsions, containing silica (S-PE) or Fuller's earth (FE-PE) were formulated. Their efficiency for skin decontamination was evaluated, in vitro, 45min after an exposure to VX, one of the most highly toxic chemical warfare agents. Pickering emulsions were compared to FE (FE-W) and silica (S-W) aqueous suspensions. PE containing an oil with a similar hydrophobicity to VX should promote its extraction. All the formulations reduced significantly the amount of VX quantified on and into the skin compared to the control. Wiping the skin surface with a pad already allowed removing more than half of VX. FE-W was the less efficient (85% of VX removed). The other formulations (FE-PE, S-PE and S-W) resulted in more than 90% of the quantity of VX removed. The charge of particles was the most influential factor. The low pH of formulations containing silica favored electrostatic interactions of VX with particles explaining the better elimination from the skin surface. Formulations containing FE had basic pH, and weak interactions with VX did not improve the skin decontamination. However, these low interactions between VX and FE promote the transfer of VX into the oil droplets in the FE-PE.

  4. The atomization of water-oil emulsions

    SciTech Connect

    Broniarz-Press, L.; Ochowiak, M.; Rozanski, J.; Woziwodzki, S.

    2009-09-15

    The paper presents the results of experimental studies on atomization of the emulsions flowing through twin-fluid atomizers obtained by the use of the digital microphotography method. The main elements of the test installation were: nozzle, reservoir, pump and measurement units of liquid flow. The photographs were taken by a digital camera with automatic flash at exposure time of 1/8000 s and subsequently analyzed using Image Pro-Plus. The oils used were mineral oils 20-90, 20-70, 20-50 and 20-30. The studies were performed at flow rates of liquid phase changed from 0.0014 to 0.011 (dm{sup 3}/s) and gas phase changed from 0.28 to 1.4 (dm{sup 3}/s), respectively. The analysis of photos shows that the droplets being formed during the liquid atomization have very different sizes. The smallest droplets have diameters of the order of 10 {mu}m. The experimental results showed that the changes in physical properties of a liquid phase lead to the significant changes in the spray characteristics. The analysis of the photos of water and emulsions atomization process showed that the droplet sizes are dependent on gas and liquid flow rates, construction of nozzle and properties of liquid. The differences between characteristics of atomization for water and emulsions have been observed. Analysis of photos on forming the droplets in air-water and air-emulsions systems showed that droplets are bigger in air-emulsion system (at the same value of gas to liquid mass ratio). The values of Sauter mean diameter (SMD) increased with increase of volume fraction of oil in emulsion. The droplet size increased with emulsion viscosity. (author)

  5. Comparative study on the hydrocyclone and the centrifuge as emulsion separators in the HNO/sub 3/-H/sub 2/O-TBP-mepasine system

    SciTech Connect

    Sulima, R.

    1986-11-01

    The separation properties of the hydrocyclone and the centrifuge were compared with regard to applying the apparatus in the uranium extraction process. The taua-bar product was applied as a comparative factor where tau-bar is the average emulsion residence time inside the separator and a-bar is the acceleration calculated for the mean radius of the separator chamber. The taua-bar values corresponding to typical operational conditions of centrifuges tested appeared to be significantly higher than those calculated for the hydrocyclone. Separation tests performed with the 1 N HNO/sub 3/-30% tributyl phosphate-Mepasine system gave negative results in the case of the hydrocyclone while the complete emulsion separation was attained in various centrifuges under conditions when taua-bargreater than or equal to9x10/sup 5/ cms . /sup -1/. The results obtained suggest that the taua-bar product can be applied as the criterion of the satisfactory phase separation in the centrifugal apparatus.

  6. How does oil type determine emulsion characteristics in concentrated Na-caseinate emulsions?

    PubMed

    Tan, Hui Lin; McGrath, Kathryn M

    2013-08-01

    Macroscopic properties and ensemble average diffusion of concentrated (dispersed phase 50-60 wt%) Na-caseinate-stabilised emulsions for three different oils (soybean oil, palm olein and tetradecane) were explored. On a volume fraction basis, pulsed gradient stimulated echo (PGSTE)-NMR data show that droplet dynamics for all three systems are similar within a region of the emulsion morphology diagram. The exact limits of the emulsion space depend however on which oil is considered. The reduced solubility of tetradecane in water, and Na-caseinate in tetradecane, result in the stabilisation of flocs during formulation. Floc formation is not observed when soybean oil or palm olein is used under identical emulsion formulation conditions. Linear rheology experiments provide indirect evidence that the local structure and the properties of the thin film interfacial domain of tetradecane emulsions vary from those of soybean oil and palm olein emulsions. Collectively these data indicate that protein/oil interactions within a system dominate over specific oil droplet structure and size distribution, which are similar in the three systems.

  7. Gelation of Soy Milk with Hagfish Exudate Creates a Flocculated and Fibrous Emulsion- and Particle Gel

    PubMed Central

    Böni, Lukas; Rühs, Patrick A.; Windhab, Erich J.; Fischer, Peter; Kuster, Simon

    2016-01-01

    Hagfish slime is an ultra dilute, elastic and cohesive hydrogel that deploys within milliseconds in cold seawater from a glandularly secreted exudate. The slime is made of long keratin-like fibers and mucin-like glycoproteins that span a network which entraps water and acts as a defense mechanism against predators. Unlike other hydrogels, the slime only confines water physically and is very susceptible to mechanical stress, which makes it unsuitable for many processing operations and potential applications. Despite its huge potential, little work has been done to improve and functionalize the properties of this hydrogel. To address this shortcoming, hagfish exudate was mixed with a soy protein isolate suspension (4% w/v) and with a soy emulsion (commercial soy milk) to form a more stable structure and combine the functionalities of a suspension and emulsion with those of the hydrogel. Hagfish exudate interacted strongly with the soy systems, showing a markedly increased viscoelasticity and water retention. Hagfish mucin was found to induce a depletion and bridging mechanism, which caused the emulsion and suspension to flocculate, making “soy slime”, a cohesive and cold-set emulsion- and particle gel. The flocculation network increases viscoelasticity and substantially contributes to liquid retention by entrapping liquid in the additional confinements between aggregated particles and protein fibers. Because the mucin-induced flocculation resembles the salt- or acid-induced flocculation in tofu curd production, the soy slime was cooked for comparison. The cooked soy slime was similar to conventional cooked tofu, but possessed a long-range cohesiveness from the fibers. The fibrous, cold-set, and curd-like structure of the soy slime represents a novel way for a cold coagulation and fiber incorporation into a suspension or emulsion. This mechanism could be used to efficiently gel functionalized emulsions or produce novel tofu-like structured food products. PMID

  8. Water-in-model oil emulsions studied by small-angle neutron scattering: interfacial film thickness and composition.

    PubMed

    Verruto, Vincent J; Kilpatrick, Peter K

    2008-11-18

    The ever-increasing worldwide demand for energy has led to the upgrading of heavy crude oil and asphaltene-rich feedstocks becoming viable refining options for the petroleum industry. Traditional problems associated with these feedstocks, particularly stable water-in-petroleum emulsions, are drawing increasing attention. Despite considerable research on the interfacial assembly of asphaltenes, resins, and naphthenic acids, much about the resulting interfacial films is not well understood. Here, we describe the use of small-angle neutron scattering (SANS) to elucidate interfacial film properties from model emulsion systems. Modeling the SANS data with both a polydisperse core/shell form factor as well as a thin sheet approximation, we have deduced the film thickness and the asphaltenic composition within the stabilizing interfacial films of water-in-model oil emulsions prepared in toluene, decalin, and 1-methylnaphthalene. Film thicknesses were found to be 100-110 A with little deviation among the three solvents. By contrast, asphaltene composition in the film varied significantly, with decalin leading to the most asphaltene-rich films (30% by volume of the film), while emulsions made in toluene and methylnaphthalene resulted in lower asphaltenic contents (12-15%). Through centrifugation and dilatational rheology, we found that trends of decreasing water resolution (i.e., increasing emulsion stability) and increasing long-time dilatational elasticity corresponded with increasing asphaltene composition in the film. In addition to the asphaltenic composition of the films, here we also deduce the film solvent and water content. Our analyses indicate that 1:1 (O/W) emulsions prepared with 3% (w/w) asphaltenes in toluene and 1 wt % NaCl aqueous solutions at pH 7 and pH 10 resulted in 80-90 A thick films, interfacial areas around 2600-3100 cm (2)/mL, and films that were roughly 25% (v/v) asphaltenic, 60-70% toluene, and 8-12% water. The increased asphaltene and water film

  9. Detonation Characteristics of Mixtures of HMX and Emulsion Explosives

    DTIC Science & Technology

    1989-04-01

    approximately 20 percent HM to an emulsion explosive results in a substantial increase in initiation sensitivity . This observation is based on the premise of an...inverse relationship between failure diameter and initiation sensitivity for the HYX’ emulsion explosive system. I ii UNCLASSIFIED IIUWAOTV...for height-of-burst experiments. The issues of safety, thermal stability, initiation sensitivity , detonation performance, mechanical properties

  10. Nanoscale and Microscale Iron Emulsions for Treating DNAPL

    NASA Technical Reports Server (NTRS)

    Geiger, Cherie L.

    2002-01-01

    This study demonstrated the feasibility of using emulsified nanoscale and microscale iron particles to enhance dehalogenation of (Dense Non-Aqueous Phase Liquid) DNAPL free-phase. The emulsified system consisted of a surfactant-stabilized, biodegradable oil-in-water emulsion with nanoscale or microscale iron particles contained within the emulsion droplets. It was demonstrated that DNAPLs, such as trichloroethene (TCE), diffuse through the oil membrane of the emulsion particle whereupon they reach an aqueous interior and the surface of an iron particle where dehalogenation takes place. The hydrocarbon reaction by-products of the dehalogenation reaction, primarily ethene (no chlorinated products detected), diffuse out of the emulsion droplet. This study also demonstrated that an iron-emulsion system could be delivered in-situ to the DNAPL pool in a soil matrix by using a simulated push well technique. Iron emulsions degraded pure TCE at a rate comparable to the degradation of dissolved phase TCE by iron particles, while pure iron had a very low degradation rate for free-phase TCE. The iron-emulsion systems can be injected into a sand matrix where they become immobilized and are not moved by flowing water. It has been documented that surfactant micelles possess the ability to pull pooled TCE into emulsion droplets where degradation of TCE takes place.

  11. Forces acting in quasi 2d emulsions

    NASA Astrophysics Data System (ADS)

    Orellana, Carlos; Lowensohn, Janna; Weeks, Eric

    We study the forces in a quasi two dimensional emulsion system. Our samples are oil-in-water emulsions confined between two close-spaced parallel plates, so that the oil droplets are deformed into pancake shapes. By means of microscopy, we measure the droplet positions and their deformation, which we can relate to the contact forces due to surface tension. We improve over prior work in our lab, achieving a better force resolution. We use this result to measure and calibrate the viscous forces acting in our system, which fully determine all the forces on the droplets. Our results can be applied to study static configurations of emulsion, as well as faster flows.

  12. Pickering emulsions for food applications: background, trends, and challenges.

    PubMed

    Berton-Carabin, Claire C; Schroën, Karin

    2015-01-01

    Particle-stabilized emulsions, also referred to as Pickering emulsions, have garnered exponentially increasing interest in recent years. This has also led to the first food applications, although the number of related publications is still rather low. The involved stabilization mechanisms are fundamentally different as compared to conventional emulsifiers, which can be an asset in terms of emulsion stability. Even though most of the research on Pickering emulsions has been conducted on model systems, with inorganic solid particles, recent progress has been made on the utilization of food-grade or food-compatible organic particles for this purpose. This review reports the latest advances in that respect, including technical challenges, and discusses the potential benefits and drawbacks of using Pickering emulsions for food applications, as an alternative to conventional emulsifier-based systems.

  13. Tuneable Rheological Properties of Fluorinated Pickering Emulsions

    NASA Astrophysics Data System (ADS)

    Chacon Orellana, Laura Andreina; Riechers, Birte; Caen, Ouriel; Baret, Jean-Christophe

    Pickering emulsions are an appealing approach to stabilize liquid-liquid dispersions without surfactants. Recently, amphiphilic silica nanoparticles have been proposed as an alternative to surfactants for droplet microfluidics applications, where aqueous drops are stabilized in fluorinated oils. This system, proved to be effective in preventing the leakage of resorufin, a model dye that was known to leak in surfactant-stabilized drops. The overall capabilities of droplet-based microfluidics technology is highly dependent on the dynamic properties of droplets, interfaces and emulsions. Therefore, fluorinated pickering emulsions dynamic properties need to be characterized, understood and controlled to be used as a substitute of already broadly studied emulsions for droplet microfluidics applications. In this study, fluorinated pickering emulsions have been found to behave as a Herschel Bulkley fluid, representing a challenge for common microfluidic operations as re-injection and sorting of droplets. We found that this behavior is controlled by the interaction between the interfacial properties of the particle-laden interface and the bulk properties of the two phases

  14. WIMP tracking with cryogenic nuclear emulsion

    NASA Astrophysics Data System (ADS)

    Kimura, M.; Naka, T.; Furuya, S.; Asada, T.; Katsuragawa, T.; Yoshimoto, M.; Umemoto, A.; Machii, S.; Ichiki, H.; Sato, O.; Hoshino, Y.

    2017-02-01

    Directional dark matter search experiments enable us to reveal the presence of Weakly Interacting Massive Particles. A promising detector for a directional measurement is a fine-grained nuclear emulsion consisting of fine crystals of silver bromide with 20 nm or 40 nm size. A critical task for the success of the experiment is to remove background tracks of electrons coming from stopping beta rays of 14C decays in the nuclear emulsion. An electron rejection power of at least 10-10 is needed in order to start a 10 kg experiment. We present a novel cryogenic approach to reject the electron background that makes use of the phonon effect in nuclear emulsion. For the proof of principle, we have been investigating the sensitivity of fine-grained nuclear emulsions as a function of temperature by exposing to gamma rays and ion beams with an ion implant system in the range of 77-300 K. Results of gamma ray exposure indicate that the electron rejection power is estimated to be better than 3 ×10-9 at 77 K. Results of ion exposure imply that fine-grained nuclear emulsion is sensitive to ions which are light and heavy and ion tracks' angle can be measured.

  15. Clinical applications of intravenous lipid emulsion therapy.

    PubMed

    Muller, Sam H; Diaz, James H; Kaye, Alan David

    2015-12-01

    Intravenous lipid emulsion (ILE; Intralipid) therapy, a standard treatment in local anesthetic toxicity, has demonstrated therapeutic efficacies for a number of different drug class-mediated toxicities. Some of these varied drug groups include antipsychotics, antidepressants, antiarrhythmics, and calcium channel blockers. To meet the objective of describing the growing number of indications for Intralipid therapy and any diverse effects and/or failures of Intralipid therapy in reversing multiple drug toxicities, we queried several Internet search engines with the key words "intravenous lipid emulsion therapy," "Intralipid," "lipid emulsion," and "local anesthetic systemic toxicity," resulting in the identification of 31 case reports for descriptive analysis. These case reports included 49 separate drug overdose cases involving ten separate drug classes which were successfully reversed with Intralipid. The education of clinicians regarding the beneficial and varied roles of Intralipid therapy in different clinical settings is warranted, particularly in terms of the potential for Intralipid therapy to reverse the toxicities of non-local anesthetic drugs.

  16. Multi-body coalescence in Pickering emulsions

    NASA Astrophysics Data System (ADS)

    Wu, Tong; Wang, Haitao; Jing, Benxin; Liu, Fang; Burns, Peter C.; Na, Chongzheng

    2015-01-01

    Particle-stabilized Pickering emulsions have shown unusual behaviours such as the formation of non-spherical droplets and the sudden halt of coalescence between individual droplets. Here we report another unusual behaviour of Pickering emulsions—the simultaneous coalescence of multiple droplets in a single event. Using latex particles, silica particles and carbon nanotubes as model stabilizers, we show that multi-body coalescence can occur in both water-in-oil and oil-in-water emulsions. The number of droplets involved in the nth coalscence event equals four times the corresponding number of the tetrahedral sequence in close packing. Furthermore, coalescence is promoted by repulsive latex and silica particles but inhibited by attractive carbon nanotubes. The revelation of multi-body coalescence is expected to help better understand Pickering emulsions in natural systems and improve their designs in engineering applications.

  17. Hydrogel microspheres for stabilization of an antioxidant enzyme: effect of emulsion cross-linking of a dual polysaccharide system on the protection of enzyme activity.

    PubMed

    Tang, Deh-Wei; Yu, Shu-Huei; Wu, Wen-Shin; Hsieh, Hao-Ying; Tsai, Yi-Chin; Mi, Fwu-Long

    2014-01-01

    Catalase is an antioxidant enzyme abundant in natural resources. However, the enzyme is usually inactivated by gastric acid and digestive enzymes after oral ingestion. In this study, carboxymethyl chitosan (CM-chitosan) and hyaluronic acid (HA) conjugate hydrogel microspheres have been prepared by an emulsion cross-linking technique to retain the activity of catalase in simulated gastrointestinal (GI) fluids. Cross-linking reduced the swelling capability and increased the resistance toward hyaluronidase digestion of prepared HA-CM-chitosan hydrogel microspheres. Catalase entrapped in the hydrogel microspheres exhibited superior stability over a wide pH range (pH 2.0 and 6.0-8.0) as compared to the native enzyme. The entrapped catalase was also protected against degradation by digestive enzymes. Following the treatments, the catalase-loaded microspheres, in contrast to native catalase, could effectively decrease the intracellular H2O2 level and protect HT-29 colonic epithelial cells against H2O2-induced oxidative damage to preserve cell viability. These results suggested that the HA-CM-chitosan hydrogel microspheres can be used for entrapment, protection and intestinal delivery of catalase for H2O2 scavenging.

  18. Influence of surfactant on the thermal behavior of marigold oil emulsions with liquid crystal phases.

    PubMed

    dos Santos, Orlando David Henrique; da Rocha-Filho, Pedro Alves

    2007-05-01

    Vegetable oils have been largely consumed owing to the interest of pharmaceutical and cosmetic industries in using natural raw materials. The production of stable emulsions with vegetable oils challenges formulators due to its variability in composition and fatty acids constitution within batches produced. In the present work, it was studied that the influence of the size of carbon chain and the number of ethylene oxide moieties of the surfactant on the thermal behavior of eight emulsions prepared with marigold oil stabilized by liquid crystal phases. Differential scanning calorimetry (DSC) was used to determine the thermal behavior of the emulsions. The ratio of bound water was calculated, being between 29.0 and 42.0%, confirming the extension of the liquid-crystalline net in the external phase. Changing the lipophilic surfactant from Ceteth-2 to Steareth-2, there was an increase in the temperature of phase transition of the liquid crystal influencing the system stability. Calorimetric study is very useful in understanding the performance of liquid crystals with the increase of temperature and to estimate emulsions stability.

  19. Emulsion design to improve the delivery of functional lipophilic components.

    PubMed

    McClements, David Julian

    2010-01-01

    The food industry has used emulsion science and technology for many years to create a diverse range of food products, such as milk, cream, soft drinks, nutritional beverages, dressings, mayonnaise, sauces, dips, deserts, ice cream, margarine, and butter. The majority of these food products are conventional oil-in-water (O/W) or water-in-oil (W/O) type emulsions. Recently, there has been increasing interest within the food industry in either improving or extending the functional performance of foods using novel structured emulsions. This article reviews recent developments in the creation of structured emulsions that could be used by the food and other industries, including nanoemulsions, multiple emulsions, multilayer emulsions, solid lipid particles, and filled hydrogel particles. These structured emulsions can be produced from food-grade [generally recognized as safe (GRAS)] ingredients (e.g., lipids, proteins, polysaccharides, surfactants, and minerals), using simple processing operations (e.g., mixing, homogenizing, and thermal processing). The structure, production, performance, and potential applications of each type of structured emulsion system are discussed.

  20. Development of an Acoustic Droplet Vaporization, Ultrasound Drug Delivery Emulsion

    NASA Astrophysics Data System (ADS)

    Fabiilli, Mario L.; Sebastian, Ian E.; Fowlkes, J. Brian

    2010-03-01

    Many therapeutic applications of ultrasound (US) include the use of pefluorocarbon (PFC) microbubbles or emulsions. These colloidal systems can be activated in the presence of US, which in the case of emulsions, results in the production of bubbles—a process known as acoustic droplet vaporization (ADV). ADV can be used as a drug delivery mechanism, thereby yielding the localized release of toxic agents such a chemotherapeutics. In this work, emulsions that contain PFC and chlorambucil, a chemotherapy drug, are formulated using albumin or lipid shells. For albumin droplets, the oil phase—which contained CHL—clearly enveloped the PFC phase. The albumin emulsion also displayed better retention of CHL in the absence of US, which was evaluated by incubating Chinese hamster ovary cells with the various formulations. Thus, the developed emulsions are suitable for further testing in ADV-induced release of CHL.

  1. Emulsion Liquid Membrane Removal of Arsenic and Strontium from Wastewater: AN Experimental and Theoretical Study.

    NASA Astrophysics Data System (ADS)

    Zhou, Ding-Wei

    The emulsion liquid membrane (ELM) technique has been successfully applied on the removal of arsenic (As) from metallurgical wastewater and the removal of strontium (Sr) from radioactive wastewater. This study consisted of experimental work and mathematical modeling. Extraction of arsenic by an emulsion liquid membrane was firstly investigated. The liquid membrane used was composed of 2-ethylhexyl alcohol (2EHA) as the extractant, ECA4360J as the surfactant, and Exxsol D-80 solvent (or heptane) as the diluent. The sulfuric acid and sodium hydroxide solutions were used as the external and internal phases, respectively. The arsenic removal efficiency reached 92% within 15 minutes in one stage. Extraction and stripping chemistries were postulated and investigated. It was observed that extraction efficiency and rate increase with the increase of acidic strength and alkali strength in the external and internal phases, respectively. It was also observed that the removal selectivity of arsenic over copper is extremely high. Strontium-90 is one of the major radioactive metals appearing in nuclear wastewater. The emulsion liquid membrane process was investigated as a separation method by using the non-radioactive ^{87}Sr as its substitute. In our study, the membrane phase was composed of di-(2-ethylhexyl) phosphoric acid (D2EHPA) as the extractant, ECA4360J as the surfactant and Exxsol D-80 as the diluent. A sulfuric acid solution was used in the internal phase as the stripping agent. The pH range in the external phase was determined by the extraction isotherm. Under the most favorable operating condition, the strontium removal efficiency can reach 98% in two minutes. Mass transfer of the emulsion liquid membrane (ELM) system was modeled mathematically. Our model took into account the following: mass transfer of solute across the film between the external phase and the membrane phase, chemical equilibrium of the extraction reaction at the external phase-membrane interface

  2. Breaking of double emulsions based on electrohydrodynamics principles.

    PubMed

    Spasic, Aleksandar M; Jovanovic, Jovan M; Manojlovic, Vaso; Jovanovic, Mica

    2016-10-01

    This research focuses on the modeling of the liquid-liquid dispersed system, including particular insight on the electrocoalescence (EC) process that occurs during the breaking of double emulsions. The representative system, used in this work, was taken from the pilot plant for solvent extraction of uranium from wet phosphoric acid. The chosen framework required for elucidation of the EC process is based on the electrohydrodynamic (EHD) principles. During the model development it was necessary to consider several theoretical concepts for easier understanding and description of the related events. The first is the concept of entities, and corresponding classification of finely dispersed systems. The second concept is an introduction of almost forgotten basic electrodynamics element the memdiode or memristor as a current controlled device, and corresponding memristive systems. Hence, the conclusions that may be withdrawn from the presented results and findings could enable easier designing of the solutions for a breaking of double emulsions problems, that is, the entrainment problems that may arise in some pilot or industrial plants. Finally, the perspectives and the remaining challenges, considering the here discussed concepts and model based on the EHD principles, are mentioned.

  3. Effects of a fish oil containing lipid emulsion on plasma phospholipid fatty acids, inflammatory markers, and clinical outcomes in septic patients: a randomized, controlled clinical trial

    PubMed Central

    2010-01-01

    Introduction The effect of parenteral fish oil in septic patients is not widely studied. This study investigated the effects of parenteral fish oil on plasma phospholipid fatty acids, inflammatory mediators, and clinical outcomes. Methods Twenty-five patients with systemic inflammatory response syndrome or sepsis, and predicted to need parenteral nutrition were randomized to receive either a 50:50 mixture of medium-chain fatty acids and soybean oil or a 50:40:10 mixture of medium-chain fatty acids, soybean oil and fish oil. Parenteral nutrition was administrated continuously for five days from admission. Cytokines and eicosanoids were measured in plasma and in lipopolysaccharide-stimulated whole blood culture supernatants. Fatty acids were measured in plasma phosphatidylcholine. Results Fish oil increased eicosapentaenoic acid in plasma phosphatidylcholine (P < 0.001). Plasma interleukin (IL)-6 concentration decreased significantly more, and IL-10 significantly less, in the fish oil group (both P < 0.001). At Day 6 the ratio PO2/FiO2 was significantly higher in the fish oil group (P = 0.047) and there were fewer patients with PO2/FiO2 <200 and <300 in the fish oil group (P = 0.001 and P = 0.015, respectively). Days of ventilation, length of intensive care unit (ICU) stay and mortality were not different between the two groups. The fish oil group tended to have a shorter length of hospital stay (22 ± 7 vs. 55 ± 16 days; P = 0.079) which became significant (28 ± 9 vs. 82 ± 19 days; P = 0.044) when only surviving patients were included. Conclusions Inclusion of fish oil in parenteral nutrition provided to septic ICU patients increases plasma eicosapentaenoic acid, modifies inflammatory cytokine concentrations and improves gas exchange. These changes are associated with a tendency towards shorter length of hospital stay. Trials Registration Clinical Trials Registration Number ISRCTN89432944 PMID:20085628

  4. The influence of emulsion structure on the Maillard reaction of ghee.

    PubMed

    Newton, Angela E; Fairbanks, Antony J; Golding, Matt; Andrewes, Paul; Gerrard, Juliet A

    2015-04-15

    Food systems, such as cream and butter, have an emulsion or emulsion-like structure. When these food emulsions are heated to high temperatures to make products such as ghee, the Maillard reaction forms a range of volatile flavour compounds. The objective of this paper was to unravel the specific influence of emulsion structure on the Maillard reaction pathways that occur during the cooking of ghee using model systems. Switching the dispersed phase from oil to water provided a means of altering the ratios of volatile compounds produced in the cooked samples. The oil-in-water emulsion generated a volatile compound profile similar to that of the fat containing two phase model matrix, whereas the water-in-oil emulsion produced a different ratio of these compounds. The ability to generate different volatile compound profiles through the use of inverted emulsion structures could point to a new avenue for control of the Maillard reaction in high temperature food systems.

  5. Rational use of intravenous fat emulsions.

    PubMed

    Pelham, L D

    1981-02-01

    The composition, effect on blood components, relative value compared with intravenous dextrose, clinical applications as a caloric and fatty acid source, adverse reactions, limitations, and administration of intravenous fat emulsions are reviewed. Fat emulsions provide essential fatty acids and calories and are primarily used to supplement of parenteral nutrition regimens. Their use as a major source of calories remains limited because of cost. However, the trend toward aligning intravenous nutrition to that of the normal diet and the increased demand for peripherally administered parenteral nutrition have increased demand for use. The advantages and disadvantages presented may be used by clinicians to assist in establishing the role of intravenous fat therapy in nutritional support services.

  6. [On bitumen emulsions in water].

    PubMed

    Rivas, Hercilio; Gutierrez, Xiomara; Silva, Felix; Chirinos, Manuel

    2003-01-01

    The most important factors, controlling the process of emulsification of highly viscous hydrocarbons in water, which are responsible for keeping the stability and other properties of these systems, are discused in this article. The effect of non-ionic surfactants, such as nonil phenol ethoxilated compounds on the interfacial behavior of bitumen/water systems is analyzed. The effect of the natural surfactants in presence or in absence of electrolytes is also analyzed. The procedures followed in order to obtain the optimal conditions of formulation and formation of bitumen in water emulsions, are discussed and the effect of some parameters on the mean droplet diameter and distribution are also considered. It was found that keeping constant mixing speed and time of mixing, the mean droplet diameter decreases as the bitumen concentration increases. Emulsion stability, which can be monitored by following the changes in mean droplet diameters and viscosity as a function of the storage time, is deeply affected by the type and concentration of surfactant.

  7. Polymerization in emulsion microdroplet reactors

    NASA Astrophysics Data System (ADS)

    Carroll, Nick J.

    concentration and micellization of the surfactant. At the same time, the silica solidifies around the surfactant structures, forming equally sized mesoporous particles. The procedure can be tuned to produce well-separated particles or alternatively particles that are linked together. The latter allows us to create 2D or 3D structures with hierarchical porosity. Oil, water, and surfactant liquid mixtures exhibit very complex phase behavior. Depending on the conditions, such mixtures give rise to highly organized structures. A proper selection of the type and concentration of surfactants determines the structuring at the nanoscale level. In this work, we show that hierarchically bimodal nanoporous structures can be obtained by templating silica microparticles with a specially designed surfactant micelle/microemulsion mixture. Tuning the phase state by adjusting the surfactant composition and concentration allows for the controlled design of a system where microemulsion droplets coexist with smaller surfactant micellar structures. The microemulsion droplet and micellar dimensions determine the two types of pore sizes (single nanometers and tens of nanometers). We also demonstrate the fabrication of carbon and carbon/platinum replicas of the silica microspheres using a "lost-wax" approach. Such particles have great potential for the design of electrocatalysts for fuel cells, chromatography separations, and other applications. It was determined that slight variations in microemulsion mixture components (electrolyte concentration, wt% of surfactants, oil to sol ratio, etc.) produces strikingly different pore morphologies and particle surface areas. Control over the size and structure of the smaller micelle-templated pores was made possible by varying the length of the hydrocarbon block within the trimethyl ammonium bromide surfactant and characterized using X-ray diffraction. The effect of emulsion aging was studied by synthesizing particles at progressive time levels from a sample

  8. Synthetic Polymers at Interfaces: Monodisperse Emulsions Multiple Emulsions and Liquid Marbles

    NASA Astrophysics Data System (ADS)

    Sun, Guanqing

    from surfactant-free emulsion polymerization were proved to be effective liquid marble stabilizers. The influence of drying conditions on the properties of liquid marbles was investigated through a macroscopic way. The pH value of the particle dispersion, which influences the protonation states of the particles before freeze-drying, has a profound influence on the property of the stabilized liquid marbles. A brief comment to the future of work of these investigated systems is delivered in the last part.

  9. Pickering Interfacial Catalysts for solvent-free biomass transformation: physicochemical behavior of non-aqueous emulsions.

    PubMed

    Fan, Zhaoyu; Tay, Astrid; Pera-Titus, Marc; Zhou, Wen-Juan; Benhabbari, Samy; Feng, Xiaoshuang; Malcouronne, Guillaume; Bonneviot, Laurent; De Campo, Floryan; Wang, Limin; Clacens, Jean-Marc

    2014-08-01

    A key challenge in biomass conversion is how to achieve valuable molecules with optimal reactivity in the presence of immiscible reactants. This issue is usually tackled using either organic solvents or surfactants to promote emulsification, making industrial processes expensive and not environmentally friendly. As an alternative, Pickering emulsions using solid particles with tailored designed surface properties can promote phase contact within intrinsically biphasic systems. Here we show that amphiphilic silica nanoparticles bearing a proper combination of alkyl and strong acidic surface groups can generate stable Pickering emulsions of the glycerol/dodecanol system in the temperature range of 35-130°C. We also show that such particles can perform as Pickering Interfacial Catalysts for the acid-catalyzed etherification of glycerol with dodecanol at 150°C. Our findings shed light on some key parameters governing emulsion stability and catalytic activity of Pickering interfacial catalytic systems. This understanding is critical to pave the way toward technological solutions for biomass upgrading able to promote eco-efficient reactions between immiscible organic reagents with neither use of solvents nor surfactants.

  10. Preparation of uniform particle-stabilized emulsions using SPG membrane emulsification.

    PubMed

    Sun, Guanqing; Qi, Feng; Wu, Jie; Ma, Guanghui; Ngai, To

    2014-06-24

    Various aspects of particle-stabilized emulsions (or so-called Pickering emulsions) have been extensively investigated during the last two decades, but the preparation of uniform Pickering emulsion droplets via a simple and scalable method has been sparingly realized. We report the preparation of uniform Pickering emulsions by Shirasu porous glass (SPG) membrane emulsification. The size of the emulsion droplets ranging from 10-50 μm can be precisely controlled by the size of the membrane pore. The emulsion droplets have a high monodispersity with coefficients of variation (CV) lower than 15% in all of the investigated systems. We further demonstrate the feasibility of locking the assembled particles at the interface, and emulsion droplets have been shown to be excellent templates for the preparation of monodisperse colloidosomes that are necessary in drug-delivery systems.

  11. Holographic DESA emulsions

    NASA Astrophysics Data System (ADS)

    Duenkel, Lothar; Eichler, Juergen; Schneeweiss, Claudia; Ackermann, Gerhard

    2005-04-01

    The DESA material is an ultra-fine grained silver bromide emulsion referring to the name of its four inventors (D)uenkel, (E)ichler, (S)chneeweiss, (A)ckermann of the University of Applied Sciences in Berlin, Germany. The thickness of the dried layer is between 5 and 7.5 μm, and the mean grain size is by about 15 nm, as determined by TEM. During manufacturing, emulsion precipitation and coating are separated strictly from spectral and chemical sensitization. Thus, a high performance could be obtained. Resolution is estimated higher than 8000 lp/mm. Sensitivity amounts to 80 up to 120 μJoules/cm2 for maximum diffraction efficiency by recording Denisyuk white-light reflection holograms at 632,8 nm (HeNe laser). The paper provides an insight into fundamentals of the ultra-fine grained silver halide technology together with new challenges for further developments under theoretical and practical aspects.

  12. FINE GRAIN NUCLEAR EMULSION

    DOEpatents

    Oliver, A.J.

    1962-04-24

    A method of preparing nuclear track emulsions having mean grain sizes less than 0.1 microns is described. The method comprises adding silver nitrate to potassium bromide at a rate at which there is always a constant, critical excess of silver ions. For minimum size grains, the silver ion concentration is maintained at the critical level of about pAg 2.0 to 5.0 during prectpitation, pAg being defined as the negative logarithm of the silver ion concentration. It is preferred to eliminate the excess silver at the conclusion of the precipitation steps. The emulsion is processed by methods in all other respects generally similar to the methods of the prior art. (AEC)

  13. Stability indicating HPLC-UV method for detection of curcumin in Curcuma longa extract and emulsion formulation.

    PubMed

    Syed, Haroon Khalid; Liew, Kai Bin; Loh, Gabriel Onn Kit; Peh, Kok Khiang

    2015-03-01

    A stability-indicating HPLC-UV method for the determination of curcumin in Curcuma longa extract and emulsion was developed. The system suitability parameters, theoretical plates (N), tailing factor (T), capacity factor (K'), height equivalent of a theoretical plate (H) and resolution (Rs) were calculated. Stress degradation studies (acid, base, oxidation, heat and UV light) of curcumin were performed in emulsion. It was found that N>6500, T<1.1, K' was 2.68-3.75, HETP about 37 and Rs was 1.8. The method was linear from 2 to 200 μg/mL with a correlation coefficient of 0.9998. The intra-day precision and accuracy for curcumin were ⩽0.87% and ⩽2.0%, while the inter-day precision and accuracy values were ⩽2.1% and ⩽-1.92. Curcumin degraded in emulsion under acid, alkali and UV light. In conclusion, the stability-indicating method could be employed to determine curcumin in bulk and emulsions.

  14. Non-coalescence of oppositely charged droplets in pH-sensitive emulsions

    PubMed Central

    Liu, Tingting; Seiffert, Sebastian; Thiele, Julian; Abate, Adam R.; Weitz, David A.; Richtering, Walter

    2012-01-01

    Like charges stabilize emulsions, whereas opposite charges break emulsions. This is the fundamental principle for many industrial and practical processes. Using micrometer-sized pH-sensitive polymeric hydrogel particles as emulsion stabilizers, we prepare emulsions that consist of oppositely charged droplets, which do not coalesce. We observe noncoalescence of oppositely charged droplets in bulk emulsification as well as in microfluidic devices, where oppositely charged droplets are forced to collide within channel junctions. The results demonstrate that electrostatic interactions between droplets do not determine their stability and reveal the unique pH-dependent properties of emulsions stabilized by soft microgel particles. The noncoalescence can be switched to coalescence by neutralizing the microgels, and the emulsion can be broken on demand. This unusual feature of the microgel-stabilized emulsions offers fascinating opportunities for future applications of these systems. PMID:22203968

  15. Role of Counterions in Controlling the Properties of Ultrasonically Generated Chitosan-Stabilized Oil-in-Water Emulsions.

    PubMed

    Colombo, Enrico; Cavalieri, Francesca; Ashokkumar, Muthupandian

    2015-06-17

    An oil-in-water emulsion was ultrasonically prepared in aqueous chitosan solutions containing different counterions. Tetradecane was used as the oil phase in order to mimic nonpolar substances used in food processes. Various acids were used to dissolve chitosan, and we found that conjugate bases of the acids used, which act as counterions to neutralize the positive charges of ammonium ions present in the chitosan backbone, played a significant role in controlling the size, size distribution, and stability of chitosan-encapsulated tedradecane emulsion droplets (microspheres). The counterion effect is also found to be strongly dependent upon tetradecane (TD)/chitosan (CS) ratio and ultrasonic power. Key observations are: (i) for a given TD/CS ratio, the size and size distribution decrease when the acid is varied from nitric acid to benzenesulfonic acid at high TD/CS ratio, and the effect becomes less significant at low TD/CS ratio; (ii) for a given acid, the size and size distribution increase with an increase in TD/CS ratio; and (iii) at low TD/CS ratio the size and size distribution are significantly influenced by the viscosity of the system. A possible mechanism for the observed counterion effect is proposed. The role of counterions, solution viscosity, and ultrasonic power in controlling the physical and functional properties of ultrasonically generated chitosan-stabilized tetradecane microspheres is discussed in detail. The key new finding of this study is that it is possible to form stable emulsions without the addition of external emulsifiers and stabilizers, but only using chitosan with different acids to dissolve chitosan. This strategy could be used in the generation of stable food emulsions.

  16. Influence of droplet charge on the chemical stability of citral in oil-in-water emulsions.

    PubMed

    Choi, Seung Jun; Decker, Eric Andrew; Henson, Lulu; Popplewell, L Michael; McClements, David Julian

    2010-08-01

    The chemical stability of citral, a flavor component widely used in beverage, food, and fragrance products, in oil-in-water emulsions stabilized by surfactants with different charge characteristics was investigated. Emulsions were prepared using cationic (lauryl alginate, LAE), non-ionic (polyoxyethylene (23) lauryl ether, Brij 35), and anionic (sodium dodecyl sulfate, SDS) surfactants at pH 3.5. The citral concentration decreased over time in all the emulsions, but the rate of decrease depended on surfactant type. After 7 d storage, the citral concentrations remaining in the emulsions were around 60% for LAE- or Brij 35-stabilized emulsions and 10% for SDS-stabilized emulsions. An increase in the local proton (H(+)) concentration around negatively charged droplet surfaces may account for the more rapid citral degradation observed in SDS-stabilized emulsions. A strong metal ion chelator (EDTA), which has previously been shown to be effective at increasing the oxidative stability of labile components, had no effect on citral stability in LAE- or Brij 35-stabilized emulsions, but it slightly decreased the initial rate of citral degradation in SDS-stabilized emulsions. These results suggest the surfactant type used to prepare emulsions should be controlled to improve the chemical stability of citral in emulsion systems.

  17. Enhanced stabilization of cloudy emulsions with gum Arabic and whey protein isolate.

    PubMed

    Klein, Miri; Aserin, Abraham; Svitov, Inna; Garti, Nissim

    2010-05-01

    Cloudy emulsions are oil-in-water (O/W) emulsions normally prepared as concentrates, further diluted, per request, into the final beverage. The cloudy emulsion provides flavor, color, and cloud (turbidity) to the soft drink. These systems are stabilized by emulsifiers and/or amphiphilic polysaccharides. Cloudy emulsions based on naturally occurring food grade emulsifiers were studied in the present work. Two charged natural biopolymers, whey protein isolate (WPI) and gum Arabic (GA), are interacted in aqueous solution to form charge-charge interactions improving the emulsion stability. The emulsions were high sheared (Microfluidizer) and characterized by particle size distribution analysis (DLS), optical centrifugation (LUMiFuge), optical microscopy observations, and turbidity measurements. Emulsions obtained from 10wt% of 3:1wt. ratio WPI:GA, at pH 7 (10wt% canola oil) show better stability than emulsions stabilized by GA or WPI alone. The droplet sizes were smaller than 1microm and did not grow significantly during 1 month of incubation at 25 degrees C. The D-limonene-based emulsion droplets were larger (> 2microm) than those made with vegetable oils immediately after preparation and underwent significant droplet size increase (coalescence) within 1 month (>8 microm). The emulsion with turbidity suitable as a cloudy emulsion was composed of 3wt% WPI:GA (3:1) and 20wt% canola oil.

  18. Stability of drug-carrier emulsions containing phosphatidylcholine mixtures.

    PubMed

    Trotta, Michele; Pattarino, Franco; Ignoni, Terenzio

    2002-03-01

    Lipid emulsion particles containing 10% of medium chain triglycerides were prepared using 2% w/w of a mixture 1:1 w/w of purified soya phosphatidylcholine and 2-hexanoyl phosphatidylcholine as emulsifier mixture, for use as drug carriers. The mean droplet sizes of emulsions, prepared using an Ultra Turrax or a high-pressure homogenizer, were about 288 and 158 nm, respectively, compared with 380 and 268 nm for emulsions containing lecithin, or 325 and 240 nm for those containing 6-phosphatidylcholine. The stability of the emulsions, determined by monitoring the decrease of a lipophilic marker at a specified level within the emulsion, and observing coalescence over time, was also greatly increased using the emulsifier mixture. The emulsion stability did not notably change in the presence of a model destabilizing drug, indomethacin. The use of a second hydrophilic surfactant to adjust the packing properties of the lecithin at the oil-water interface provided an increase in the stability of lipid emulsions, and this may be of importance in the formulation of drug delivery systems.

  19. Influence of different types and proportions of added edible seaweeds on characteristics of low-salt gel/emulsion meat systems.

    PubMed

    Cofrades, S; López-López, I; Solas, M T; Bravo, L; Jiménez-Colmenero, F

    2008-08-01

    The effects of three different types of edible seaweeds, Sea Spaghetti (Himanthalia elongata), Wakame (Undaria pinnatifida), and Nori (Porphyra umbilicalis) added at two concentrations (2.5% and 5% dry matter) on the physicochemical and morphological characteristics of gel/emulsion systems were evaluated. The addition of seaweeds improved (P<0.05) water- and fat-binding properties except in the case of Nori added at 2.5%. Hardness and chewiness of the cooked products with added seaweed were higher (P<0.05), and springiness and cohesiveness were lower (P<0.05) than in control samples. Colour changes in meat systems were affected by the type of seaweed. The morphology of sample differed depending on the type of seaweed added, and this is the result of differences in physical and chemical characteristic of the seaweed powder used. In general, products formulated with the brown seaweeds (Sea Spaghetti and Wakame) exhibited similar behaviour, different from that of products made with the red seaweed Nori.

  20. Impact of parenteral lipid emulsions on the metabolomic phenotype in preterm TPN-fed piglets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lipids in parenteral nutrition provide essential fatty acids and are a major source of energy for hospitalized neonates. Intralipid (IL) is the only approved lipid emulsion in the U.S, but new generation emulsions include Omegaven (OV) and SMOFlipid (SL). There are no studies describing the metaboli...

  1. Impact of parenteral lipid emulsions on metabolomic phenotype in preterm TPN-fed piglets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lipids in parenteral nutrition provide essential fatty acids and are a major source of energy for hospitalized neonates. Intralipid (IL) is the only approved lipid emulsion in the US, but new generation emulsions include Omegaven (OV) and SMOFlipid (SL). There are no studies describing the metabolit...

  2. Dehydration of oil waste emulsions by means of flocculants

    SciTech Connect

    Gandurina, L.V.; Butseva, L.N.; Shtondina, V.S.

    1995-05-01

    Oil waste emulsions are formed in the course of pumping petroleum crudes and products and are collected from the surfaces of equipment in recirculating water systems and wastewater disposal facilities (oil separators, sand traps, oil traps, holding pits for accidental spills, settlers, ponds, sludge accumulators, and so on). Emulsions are also obtained in the course of cleaning equipment in crude oil desalting and dehydration units. Such emulsions are stable, structurized systems that are very resistant to dewatering by heating and settling in separator tanks. In order to break stabilized emulsions, i.e., in order to ensure complete coalescence of drops when they collide, it is not sufficient to increase the forces of mutual attraction of drops at the moment of collision; in addition, the protective shell must be either destroyed or weakened. Demulsifying agents, or surfactants, will displace the stabilizers. This report is concerned with demulsifier efficiency.

  3. Decompressing Emulsion Droplets Favors Coalescence

    NASA Astrophysics Data System (ADS)

    Bremond, Nicolas; Thiam, Abdou R.; Bibette, Jérôme

    2008-01-01

    The destabilization process of an emulsion under flow is investigated in a microfluidic device. The experimental approach enables us to generate a periodic train of droplet pairs, and thus to isolate and analyze the basic step of the destabilization, namely, the coalescence of two droplets which collide. We demonstrate a counterintuitive phenomenon: coalescence occurs during the separation phase and not during the impact. Separation induces the formation of two facing nipples in the contact area that hastens the connection of the interfaces prior to fusion. Moreover, droplet pairs initially stabilized by surfactants can be destabilized by forcing the separation. Finally, we note that the fusion mechanism is responsible for a cascade of coalescence events in a compact system of droplets where the separation is driven by surface tension.

  4. Rubberized asphalt emulsion

    SciTech Connect

    Wilkes, E.

    1986-09-02

    A method is described of making a rubberized asphalt composition which comprises the steps of: (a) combining asphalt with a hydrocarbon oil having a flash point of 300/sup 0/F. or more to provide a homogenous asphalt-oil mixture or solution, (b) then combining the asphalt-oil mixture with a particulate rubber at a temperature sufficient to provide a homogenous asphalt-rubber-oil gel, and (c) emulsifying the asphalt-rubber-oil gel by passing the gel, water, and an emulsifying agent through a colloid mill to provide an emulsion.

  5. Ocean sequestration of carbon dioxide: modeling the deep ocean release of a dense emulsion of liquid Co2-in-water stabilized by pulverized limestone particles.

    PubMed

    Golomb, D; Pennell, S; Ryan, D; Barry, E; Swett, P

    2007-07-01

    The release into the deep ocean of an emulsion of liquid carbon dioxide-in-seawater stabilized by fine particles of pulverized limestone (CaCO3) is modeled. The emulsion is denser than seawater, hence, it will sink deeper from the injection point, increasing the sequestration period. Also, the presence of CaCO3 will partially buffer the carbonic acid that results when the emulsion eventually disintegrates. The distance that the plume sinks depends on the density stratification of the ocean, the amount of the released emulsion, and the entrainment factor. When released into the open ocean, a plume containing the CO2 output of a 1000 MW(el) coal-fired power plant will typically sink hundreds of meters below the injection point. When released from a pipe into a valley on the continental shelf, the plume will sink about twice as far because of the limited entrainment of ambient seawater when the plume flows along the valley. A practical system is described involving a static mixer for the in situ creation of the CO2/seawater/pulverized limestone emulsion. The creation of the emulsion requires significant amounts of pulverized limestone, on the order of 0.5 tons per ton of liquid CO2. That increases the cost of ocean sequestration by about $13/ ton of CO2 sequestered. However, the additional cost may be compensated by the savings in transportation costs to greater depth, and because the release of an emulsion will not acidify the seawater around the release point.

  6. Synthesis, characterization, and morphology study of poly(acrylamide-co-acrylic acid)-grafted-poly(styrene-co-methyl methacrylate) "raspberry"-shape like structure microgels by pre-emulsified semi-batch emulsion polymerization.

    PubMed

    Ramli, Ros Azlinawati; Hashim, Shahrir; Laftah, Waham Ashaier

    2013-02-01

    A novel microgels were polymerized using styrene (St), methyl methacrylate (MMA), acrylamide (AAm), and acrylic acid (AAc) monomers in the presence of N,N'-methylenebisacrylamide (MBA) cross-linker. Pre-emulsified monomer was first prepared followed by polymerizing monomers using semi-batch emulsion polymerization. Fourier Transform Infrared Spectroscopy (FTIR) and (1)H Nuclear Magnetic Resonance (NMR) were used to determine the chemical structure and to indentify the related functional group. Grafting and cross-linking of poly(acrylamide-co-acrilic acid)-grafted-poly(styrene-co-methyl methacrylate) [poly(AAm-co-AAc)-g-poly(St-co-MMA)] microgels are approved by the disappearance of band at 1300 cm(-1), 1200 cm(-1) and 1163 cm(-1) of FTIR spectrum and the appearance of CH peaks at 5.5-5.7 ppm in (1)H NMR spectrum. Scanning Electron Microscope (SEM) images indicated that poly(St-co-MMA) particle was lobed morphology coated by cross-linked poly(AAm-co-AAc) shell. Furthermore, SEM results revealed that poly(AAm-co-AAc)-g-poly(St-co-MMA) is composite particle that consist of "raspberry"-shape like structure core. Internal structures of the microgels showed homogeneous network of pores, an extensive interconnection among pores, thicker pore walls, and open network structures. Water absorbency test indicated that the sample with particle size 0.43 μm had lower equilibrium water content, % than the sample with particle size 7.39 μm.

  7. Programmed emulsions for sodium reduction in emulsion based foods.

    PubMed

    Chiu, Natalie; Hewson, Louise; Fisk, Ian; Wolf, Bettina

    2015-05-01

    In this research a microstructure approach to reduce sodium levels in emulsion based foods is presented. If successful, this strategy will enable reduction of sodium without affecting consumer satisfaction with regard to salty taste. The microstructure approach comprised of entrapment of sodium in the internal aqueous phase of water-in-oil-in-water emulsions. These were designed to destabilise during oral processing when in contact with the salivary enzyme amylase in combination with the mechanical manipulation of the emulsion between the tongue and palate. Oral destabilisation was achieved through breakdown of the emulsion that was stabilised with a commercially modified octenyl succinic anhydride (OSA)-starch. Microstructure breakdown and salt release was evaluated utilising in vitro, in vivo and sensory methods. For control emulsions, stabilised with orally inert proteins, no loss of structure and no release of sodium from the internal aqueous phase was found. The OSA-starch microstructure breakdown took the initial form of oil droplet coalescence. It is hypothesised that during this coalescence process sodium from the internalised aqueous phase is partially released and is therefore available for perception. Indeed, programmed emulsions showed an enhancement in saltiness perception; a 23.7% reduction in sodium could be achieved without compromise in salty taste (p < 0.05; 120 consumers). This study shows a promising new approach for sodium reduction in liquid and semi-liquid emulsion based foods.

  8. 21 CFR 862.1450 - Lactic acid test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ....1450 Lactic acid test system. (a) Identification. A lactic acid test system is a device intended to measure lactic acid in whole blood and plasma. Lactic acid measurements that evaluate the acid-base status... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Lactic acid test system. 862.1450 Section...

  9. 21 CFR 862.1450 - Lactic acid test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ....1450 Lactic acid test system. (a) Identification. A lactic acid test system is a device intended to measure lactic acid in whole blood and plasma. Lactic acid measurements that evaluate the acid-base status... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Lactic acid test system. 862.1450 Section...

  10. 21 CFR 862.1450 - Lactic acid test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ....1450 Lactic acid test system. (a) Identification. A lactic acid test system is a device intended to measure lactic acid in whole blood and plasma. Lactic acid measurements that evaluate the acid-base status... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Lactic acid test system. 862.1450 Section...

  11. 21 CFR 862.1450 - Lactic acid test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Lactic acid test system. 862.1450 Section 862.1450....1450 Lactic acid test system. (a) Identification. A lactic acid test system is a device intended to measure lactic acid in whole blood and plasma. Lactic acid measurements that evaluate the acid-base...

  12. 21 CFR 862.1450 - Lactic acid test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lactic acid test system. 862.1450 Section 862.1450....1450 Lactic acid test system. (a) Identification. A lactic acid test system is a device intended to measure lactic acid in whole blood and plasma. Lactic acid measurements that evaluate the acid-base...

  13. [Multiple emulsions; bioactive compounds and functional foods].

    PubMed

    Jiménez-Colmenero, Francisco

    2013-01-01

    The continued appearance of scientific evidence about the role of diet and/or its components in health and wellness, has favored the emergence of functional foods which currently constitute one of the chief factors driving the development of new products. The application of multiple emulsions opens new possibilities in the design and development of functional foods. Multiple emulsions can be used as an intermediate product (food ingredient) into technological strategies normally used in the optimization of the presence of bioactive compounds in healthy and functional foods. This paper presents a summary of the types, characteristics and formation of multiple emulsions, possible location of bioactive compounds and their potential application in the design and preparation of healthy and functional foods. Such applications are manifested particularly relevant in relation to quantitative and qualitative aspects of lipid material (reduced fat/calories and optimization of fatty acid profile), encapsulation of bioactive compounds mainly hydrophilic and sodium reduction. This strategy offers interesting possibilities regarding masking flavours and improving sensory characteristics of foods.

  14. Improving the detection efficiency in nuclear emulsion trackers

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Bozza, C.; Buonaura, A.; Consiglio, L.; D`Ambrosio, N.; Lellis, G. De; De Serio, M.; Di Capua, F.; Di Crescenzo, A.; Di Ferdinando, D.; Di Marco, N.; Fini, R. A.; Galati, G.; Giacomelli, G.; Grella, G.; Hosseini, B.; Kose, U.; Lauria, A.; Longhin, A.; Mandrioli, G.; Mauri, N.; Medinaceli, E.; Montesi, M. C.; Paoloni, A.; Pastore, A.; Patrizii, L.; Pozzato, M.; Pupilli, F.; Rescigno, R.; Roda, M.; Rosa, G.; Schembri, A.; Shchedrina, T.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Spinetti, M.; Stellacci, S. M.; Tenti, M.; Tioukov, V.

    2015-03-01

    Nuclear emulsion films are a tracking device with unique space resolution. Their use in nowadays large-scale experiments relies on the availability of automated microscope operating at very high speed. In this paper we describe the features and the latest improvements of the European Scanning System, a last-generation automated microscope for emulsion scanning. In particular, we present a new method for the recovery of tracking inefficiencies. Stacks of double coated emulsion films have been exposed to a 10 GeV/c pion beam. Efficiencies as high as 98% have been achieved for minimum ionising particle tracks perpendicular to the emulsion films and of 93% for tracks with tan(θ) ≃ 0.8.

  15. Structuring food emulsions in the gastrointestinal tract to modify lipid digestion.

    PubMed

    Singh, Harjinder; Ye, Aiqian; Horne, David

    2009-03-01

    The importance of nutrient lipids in the human diet has led to major advances in understanding the mechanisms of lipid digestion and absorption. With these advances has come new recognition that the matrix in which lipids are presented (i.e. food structure) in the diet could influence the rate of lipid digestion and hence the bioavailability of fatty acids. As a consequence, there is growing interest in understanding how food material properties can be manipulated under physiological conditions to control the uptake of lipids and lipid-soluble components. The lipids in many, if not most, processed foods are normally present as emulsions, which can be end products in themselves or part of a more complex food system. In this review, we discuss the formation and properties of oil-in-water (O/W) emulsions, especially how these emulsions are modified as they traverse through the gastrointestinal tract. Among other factors, the changes in the nature of the droplet adsorbed layer and the droplet size play a major role in controlling the action of lipases and lipid digestion. Greater knowledge and understanding of how the digestive system treats, transports and utilizes lipids will allow the microstructural design of foods to achieve a specific, controlled physiological response.

  16. Cellulose Nanocrystals as Water in Water Emulsion Stabilizers

    NASA Astrophysics Data System (ADS)

    Peddireddy, Karthik Reddy; Capron, Isabelle; Nicolai, Taco; Benyahia, Lazhar

    Cellulose is the most abundant polymer on the earth. Thus, it is very much desirable to find as many practical applications as possible for it. Cellulose, in its original form, contains both amorphous and crystalline parts. It is possible to separate both parts by dissolving the amorphous part in concentrated sulfuric acid. The remaining crystalline cellulose part exist in the form of rod-like particles. The dimensions of the particles depend on the source. We produce the particles from the acid hydrolysis of cotton cellulose fibers. It results in cellulose nanocrystals (CNCs) with dimensions of ~150 nm x 6 nm x 6 nm. It is well known that CNCs could very efficiently stabilize oil in water (O/W) emulsions by forming very dense monolayers of CNCs at O-W interfaces. However, it is not yet known whether they could also stabilize water in water (W/W) emulsions. The W/W emulsions can be produced by any two incompatible polymers. It is challenging to find effective stabilizers for W/W emulsions due to ultralow interfacial tension and large interfacial thickness. In this talk, I will show the efficiency and effectiveness of these one-dimensional rods as W/W emulsion stabilizers.

  17. Generation of colloidal granules and capsules from double emulsion drops

    NASA Astrophysics Data System (ADS)

    Hess, Kathryn S.

    Assemblies of colloidal particles are extensively used in ceramic processing, pharmaceuticals, inks and coatings. In this project, the aim was to develop a new technique to fabricate monodispersed colloidal assemblies. The use of microfluidic devices and emulsion processing allows for the fabrication of complex materials that can be used in a variety of applications. A microfluidic device is used to create monodispersed water/oil/water (w/o/w) double emulsions with interior droplets of colloidal silica suspension ranging in size from tens to hundreds of microns. By tailoring the osmotic pressure using glycerol as a solute in the continuous and inner phases of the emulsion, we can control the final volume size of the monodispersed silica colloidal crystals that form in the inner droplets of the double emulsion. Modifying the ionic strength in the colloidal dispersion can be used to affect the particle-particle interactions and crystal formation of the final colloidal particle. This w/o/w technique has been used with other systems of metal oxide colloids and cellulose nanocrystals. Encapsulation of the colloidal suspension in a polymer shell for the generation of ceramic-polymer core-shell particles has also been developed. These core-shell particles have spawned new research in the field of locally resonant acoustic metamaterials. Systems and chemistries for creating cellulose hydrogels within the double emulsions have also been researched. Water in oil single emulsions and double emulsions have been used to create cellulose hydrogel spheres in the sub-100 micron diameter range. Oil/water/oil double emulsions allow us to create stable cellulose capsules. The addition of a second hydrogel polymer, such as acrylate or alginate, further strengthens the cellulose gel network and can also be processed into capsules and particles using the microfluidic device. This work could have promising applications in acoustic metamaterials, personal care products, pharmaceuticals

  18. Formation and stability of polychlorinated biphenyl Pickering emulsions.

    PubMed

    Roy-Perreault, Andréanne; Kueper, Bernard H; Rawson, Jim

    2005-03-01

    An emulsion stabilized by colloidal suspensions of finely divided solids is known as a Pickering emulsion. The potential for polychlorinated biphenyls (PCBs) to form Pickering emulsions ex situ when in contact with powdered solids, such as clays and metal oxides, is investigated here. Bentonite, iron oxide and magnesium oxide dispersions proved to be robust Pickering emulsion stabilizers, whereas manganese oxide dispersions were not. Batch experiments revealed that emulsions can be formed using a moderately low energy input and can be stabilized with solid concentrations as low as 0.5 wt.%. For the base conditions (volumetric oil fraction (phi(oil))=30 vol.%; solid concentration (chi)=2 wt.%), the formed emulsions were indefinitely stable and the initial average droplet diameters varied from 80 to 258 mum, depending on the solid used in the colloidal dispersion. The average droplet size varied at early time, but for most conditions stabilized to a steady-state value 1 week after preparation. The effect of Ostwald ripening was limited. At greater than 0.5 wt.% concentration, the efficiency of the solid dispersion as a stabilizer was dependant on the volumetric oil fraction but not on the solid concentration. Generally, systems with volumetric oil fractions outside of the 20-70 vol.% range were unstable. The emulsions' droplet stability, average droplet size and size distribution were observed to vary as a function of the amount of energy provided to the system, the volumetric oil fraction, and the concentration of the solid in the aqueous dispersion. It is hypothesized that drilling through fractured rock in the immediate vicinity of dense, non-aqueous phase liquid (DNAPL) PCBs may provide both the energy and solid material necessary to form Pickering emulsions.

  19. Factors influencing the stability and type of hydroxyapatite stabilized Pickering emulsion.

    PubMed

    Zhang, Ming; Wang, Ai-Juan; Li, Jun-Ming; Song, Na; Song, Yang; He, Rui

    2017-01-01

    Hydroxyapatite (HAp) nanoparticle stabilized Pickering emulsion was fabricated with poly(l-lactic acid) dissolved in dichloromethane (CH2Cl2) solution as oil phase and HAp aqueous dispersion as aqueous phase. Pickering emulsion was cured via in situ solvent evaporation method. Effect of PLLA concentrations, pH value, HAp concentrations, oil-water ratio, emulsification rates and times were studied on emulsion stability and emulsion type, etc. The results indicated emulsion stability increased with the increase of HAp concentration, emulsification rate and time; it is very stable when pH value of aqueous phase was adjusted to 10. Stable W/O and O/W emulsions were fabricated successfully using as-received HAp particles as stabilizer by adjusting the fabricating parameters. The interaction between HAp and PLLA played an important role to stabilize Pickering emulsions. SEM results indicated that both microsphere and porous materials were fabricated using emulsion stabilized by unmodified HAp nanoparticles, implying that both W/O and O/W emulsion type were obtained.

  20. Micellar emulsions composed of mPEG-PCL/MCT as novel nanocarriers for systemic delivery of genistein: a comparative study with micelles

    PubMed Central

    Zhang, Tianpeng; Wang, Huan; Ye, Yanghuan; Zhang, Xingwang; Wu, Baojian

    2015-01-01

    Polymeric micelles receive considerable attention as drug delivery vehicles, depending on the versatility in drug solubilization and targeting therapy. However, their use invariably suffers with poor stability both in in vitro and in vivo conditions. Here, we aimed to develop a novel nanocarrier (micellar emulsions, MEs) for a systemic delivery of genistein (Gen), a poorly soluble anticancer agent. Gen-loaded MEs (Gen-MEs) were prepared from methoxy poly(ethylene glycol)-block-(ε-caprolactone) and medium-chain triglycerides (MCT) by solvent-diffusion technique. Nanocarriers were characterized by dynamic light scattering, transmission electron microscopy, and in vitro release. The resulting Gen-MEs were approximately 46 nm in particle size with a narrow distribution. Gen-MEs produced a different in vitro release profile from the counterpart of Gen-ME. The incorporation of MCT significantly enhanced the stability of nanoparticles against dilution with simulated body fluid. Pharmacokinetic study revealed that MEs could notably extend the mean retention time of Gen, 1.57- and 7.38-fold as long as that of micelles and solution formulation, respectively, following intravenous injection. Furthermore, MEs markedly increased the elimination half-life (t1/2β) of Gen, which was 2.63-fold larger than that of Gen solution. Interestingly, Gen distribution in the liver and kidney for MEs group was significantly low relative to the micelle group in the first 2 hours, indicating less perfusion in such two tissues, which well accorded with the elongated mean retention time. Our findings suggested that MEs may be promising carriers as an alternative of micelles to systemically deliver poorly soluble drugs. PMID:26491290

  1. Review of Intravenous Lipid Emulsion Therapy

    PubMed Central

    2016-01-01

    Intravenous fat emulsion (IVFE) is an important source of calories and essential fatty acids for patients receiving parenteral nutrition (PN). Administered as an individual infusion or combined with PN, the fats provided by IVFE are vital for cellular structural function and metabolism. The affinity of some medications to lipids has led to the use of IVFE as a treatment for any lipophilic drug overdose. This article will explain the available formulations of IVFE, administration, and maintenance issues, as well as the risks and benefits for various applications. PMID:27828934

  2. Sulfuric acid thermoelectrochemical system and method

    DOEpatents

    Ludwig, Frank A.

    1989-01-01

    A thermoelectrochemical system in which an electrical current is generated between a cathode immersed in a concentrated sulfuric acid solution and an anode immersed in an aqueous buffer solution of sodium bisulfate and sodium sulfate. Reactants consumed at the electrodes during the electrochemical reaction are thermochemically regenerated and recycled to the electrodes to provide continuous operation of the system.

  3. Micro-electro-mechanical systems phosphoric acid fuel cell

    DOEpatents

    Sopchak, David A.; Morse, Jeffrey D.; Upadhye, Ravindra S.; Kotovsky, Jack; Graff, Robert T.

    2010-12-21

    A phosphoric acid fuel cell system comprising a porous electrolyte support, a phosphoric acid electrolyte in the porous electrolyte support, a cathode electrode contacting the phosphoric acid electrolyte, and an anode electrode contacting the phosphoric acid electrolyte.

  4. Micro-electro-mechanical systems phosphoric acid fuel cell

    DOEpatents

    Sopchak, David A.; Morse, Jeffrey D.; Upadhye, Ravindra S.; Kotovsky, Jack; Graff, Robert T.

    2010-08-17

    A phosphoric acid fuel cell system comprising a porous electrolyte support, a phosphoric acid electrolyte in the porous electrolyte support, a cathode electrode contacting the phosphoric acid electrolyte, and an anode electrode contacting the phosphoric acid electrolyte.

  5. Acid sensing by the Drosophila olfactory system.

    PubMed

    Ai, Minrong; Min, Soohong; Grosjean, Yael; Leblanc, Charlotte; Bell, Rati; Benton, Richard; Suh, Greg S B

    2010-12-02

    The odour of acids has a distinct quality that is perceived as sharp, pungent and often irritating. How acidity is sensed and translated into an appropriate behavioural response is poorly understood. Here we describe a functionally segregated population of olfactory sensory neurons in the fruitfly, Drosophila melanogaster, that are highly selective for acidity. These olfactory sensory neurons express IR64a, a member of the recently identified ionotropic receptor (IR) family of putative olfactory receptors. In vivo calcium imaging showed that IR64a+ neurons projecting to the DC4 glomerulus in the antennal lobe are specifically activated by acids. Flies in which the function of IR64a+ neurons or the IR64a gene is disrupted had defects in acid-evoked physiological and behavioural responses, but their responses to non-acidic odorants remained unaffected. Furthermore, artificial stimulation of IR64a+ neurons elicited avoidance responses. Taken together, these results identify cellular and molecular substrates for acid detection in the Drosophila olfactory system and support a labelled-line mode of acidity coding at the periphery.

  6. Droplet-based microfluidics and the dynamics of emulsions

    NASA Astrophysics Data System (ADS)

    Baret, Jean-Christophe; Brosseau, Quentin; Semin, Benoit; Qu, Xiaopeng

    2012-02-01

    Emulsions are complex fluids already involved for a long time in a wide-range of industrial processes, such as, for example, food, cosmetics or materials synthesis [1]. More recently, applications of emulsions have been extended to new fields like biotechnology or biochemistry where the compartmentalization of compounds in emulsion droplets is used to parallelise (bio-) chemical reactions [2]. Interestingly, these applications pinpoint to fundamental questions dealing with surfactant dynamics, dynamic surface tension, hydrodynamic interactions and electrohydrodynamics. Droplet-based microfluidics is a very powerful tool to quantitatively study the dynamics of emulsions at the single droplet level or even at the single interface level: well-controlled emulsions are produced and manipulated using hydrodynamics, electrical forces, optical actuation and combination of these effects. We will describe here how droplet-based microfluidics is used to extract quantitative informations on the physical-chemistry of emulsions for a better understanding and control of the dynamics of these systems [3].[4pt] [1] J. Bibette et al. Rep. Prog. Phys., 62, 969-1033 (1999)[0pt] [2] A. Theberge et al., Angewandte Chemie Int. Ed. 49, 5846 (2010)[0pt] [3] J.-C. Baret et al., Langmuir, 25, 6088 (2009)

  7. Determination of emulsion explosives with Span-80 as emulsifier by gas chromatography-mass spectrometry.

    PubMed

    Tian, Fei-Fei; Yu, Jing; Hu, Jia-Hong; Zhang, Yong; Xie, Meng-Xia; Liu, Yuan; Wang, Xiang-Feng; Liu, Hai-Ling; Han, Jie

    2011-06-03

    A novel approach for identification and determination of emulsion explosives with Span-80 (sorbitol mono-oleate) as the emulsifier and their postblast residues by gas chromatography-mass spectrometry (GC-MS) has been developed. 24 kinds of emulsion explosives collected have been processed by transesterification reaction with metholic KOH solution and the emulsifier has turned into methyl esters of fatty acids. From the peak area ratios of their methyl esters, most of these emulsion explosives can be differentiated. In order to detect the postblast residues of emulsion explosives, the sorbitols in the emulsifier Span-80 obtained after transesterification reaction have been further derivatized by silylation reaction with N,O-bis-(trimethylsilyl)trifluoroacetamide (BSTFA) containing 1% trimethylchlorosilane (TMCS) as the derivatizing reagent. The derivatization conditions were optimized and the derivatives were determined by GC-MS. The results showed that the silylation derivatives of sorbitol and it isomers, combined with hydrocarbon compounds and methyl esters of fatty acids, were the characteristic components for identification of the emulsion explosives. The established approach was applied to analyze the postblast residues of emulsion explosives. It has been found that the method was sensitive and specific, especially when detecting the derivatives of sorbitol and its isomers by GC-MS in selecting ion mode. The information of the characteristic components can help probe the origin of the emulsion explosives and providing scientific evidences and clues for solving the crimes of the emulsion explosive explosion.

  8. To Model Chemical Reactivity in Heterogeneous Emulsions, Think Homogeneous Microemulsions.

    PubMed

    Bravo-Díaz, Carlos; Romsted, Laurence Stuart; Liu, Changyao; Losada-Barreiro, Sonia; Pastoriza-Gallego, Maria José; Gao, Xiang; Gu, Qing; Krishnan, Gunaseelan; Sánchez-Paz, Verónica; Zhang, Yongliang; Dar, Aijaz Ahmad

    2015-08-25

    Two important and unsolved problems in the food industry and also fundamental questions in colloid chemistry are how to measure molecular distributions, especially antioxidants (AOs), and how to model chemical reactivity, including AO efficiency in opaque emulsions. The key to understanding reactivity in organized surfactant media is that reaction mechanisms are consistent with a discrete structures-separate continuous regions duality. Aggregate structures in emulsions are determined by highly cooperative but weak organizing forces that allow reactants to diffuse at rates approaching their diffusion-controlled limit. Reactant distributions for slow thermal bimolecular reactions are in dynamic equilibrium, and their distributions are proportional to their relative solubilities in the oil, interfacial, and aqueous regions. Our chemical kinetic method is grounded in thermodynamics and combines a pseudophase model with methods for monitoring the reactions of AOs with a hydrophobic arenediazonium ion probe in opaque emulsions. We introduce (a) the logic and basic assumptions of the pseudophase model used to define the distributions of AOs among the oil, interfacial, and aqueous regions in microemulsions and emulsions and (b) the dye derivatization and linear sweep voltammetry methods for monitoring the rates of reaction in opaque emulsions. Our results show that this approach provides a unique, versatile, and robust method for obtaining quantitative estimates of AO partition coefficients or partition constants and distributions and interfacial rate constants in emulsions. The examples provided illustrate the effects of various emulsion properties on AO distributions such as oil hydrophobicity, emulsifier structure and HLB, temperature, droplet size, surfactant charge, and acidity on reactant distributions. Finally, we show that the chemical kinetic method provides a natural explanation for the cut-off effect, a maximum followed by a sharp reduction in AO efficiency with

  9. Effects of Additions of Monascus and Laccaic acid on the Color and Quality Properties of Nitrite-Free Emulsion Sausage during Refrigerated Storage

    PubMed Central

    Moon, Sung-Sil

    2017-01-01

    This effect of Monascus and Laccaic acid on the chemical composition, physical, texture and sensory properties of sausage were investigated during storage. Eight treatments (T) of sausage such as T1 (12 ppm sodium nitrite), while T2, T3, T4, T5, T6 and T7 were formulated with different ratios of Monascus/Laccaic acid: 63/7.0, 108/12, 135/15, 59.5/10.5, 102/18 and 127.5/22.5 ppm, respectively. The batch formulated without nitrite or Monascus and laccaic acid was served as control (C). The control sausages had higher pH values compared to the treated ones at 3, 10 and 28 d storage (p<0.05). After 10 d storage, the pH values decreased in treated sausage samples (p<0.05). The T1 and T4 presented the lowest yellowness and lightness values, respectively over the storage period. The redness values were increased as increasing Monascus and Laccaic acid amounts (T2-T4, T5-T7). The addition of Monascus and Laccaic acid had significantly higher hardness and springiness values (p<0.05) compared with the control in 3, 19 or 28 d storage. The results indicated that the addition of Monascus and Laccaic acid could improve the redness of the products. PMID:28316466

  10. Home Parenteral Nutrition: Fat Emulsions and Potential Complications.

    PubMed

    Mundi, Manpreet S; Salonen, Bradley R; Bonnes, Sara

    2016-10-01

    Since the first intravenous nutrition support attempt with olive oil in the 17th century, intravenous fat emulsions (IVFEs) have evolved to become an integral component in the management of patients receiving home parenteral nutrition (HPN). IVFEs serve as a calorie source and provide essential fatty acids (linoleic acid and α-linolenic acid) in patients unable to achieve adequate intake of these fatty acids through alternative means. However, IVFE use is also associated with multiple complications, including increased infection risk, liver disease, and systemic proinflammatory states. In the United States, most IVFEs are composed of 100% soybean oil; internationally multiple alternative IVFEs (using fish oil, olive oil, and long- and medium-chain triglycerides) are available or being developed. The hope is that these IVFEs will prevent, or decrease the risk of, some of the HPN-associated complications. The goal of this article is to review how IVFEs came into use, their composition and metabolism, options for IVFE delivery in HPN, benefits and risks of IVFE use, and strategies to minimize the risks associated with IVFE use in HPN patients.

  11. Removal of phenols from aqueous solutions by emulsion liquid membranes.

    PubMed

    Reis, M Teresa A; Freitas, Ondina M F; Agarwal, Shiva; Ferreira, Licínio M; Ismael, M Rosinda C; Machado, Remígio; Carvalho, Jorge M R

    2011-09-15

    The present study deals with the extraction of phenols from aqueous solutions by using the emulsion liquid membranes technique. Besides phenol, two derivatives of phenol, i.e., tyrosol (2-(4-hydroxyphenyl)ethanol) and p-coumaric acid (4-hydroxycinnamic acid), which are typical components of the effluents produced in olive oil plants, were selected as the target solutes. The effect of the composition of the organic phase on the removal of solutes was examined. The influence of pH of feed phase on the extraction of tyrosol and p-coumaric was tested for the membrane with Cyanex 923 as an extractant. The use of 2% Cyanex 923 allowed obtaining a very high extraction of phenols (97-99%) in 5-6 min of contact time for either single solute solutions or for their mixtures. The removal efficiency of phenol and p-coumaric acid attained equivalent values by using the system with 2% isodecanol, but the removal rate of tyrosol was found greatly reduced. The extraction of tyrosol and p-coumaric acid from their binary mixture was also analysed for different operating conditions like the volume ratio of feed phase to stripping phase (sodium hydroxide), the temperature and the initial concentration of solute in the feed phase.

  12. 21 CFR 862.1295 - Folic acid test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Folic acid test system. 862.1295 Section 862.1295....1295 Folic acid test system. (a) Identification. A folic acid test system is a device intended to measure the vitamin folic acid in plasma and serum. Folic acid measurements are used in the diagnosis...

  13. 21 CFR 862.1290 - Fatty acids test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Fatty acids test system. 862.1290 Section 862.1290....1290 Fatty acids test system. (a) Identification. A fatty acids test system is a device intended to measure fatty acids in plasma and serum. Measurements of fatty acids are used in the diagnosis...

  14. 21 CFR 862.1295 - Folic acid test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Folic acid test system. 862.1295 Section 862.1295....1295 Folic acid test system. (a) Identification. A folic acid test system is a device intended to measure the vitamin folic acid in plasma and serum. Folic acid measurements are used in the diagnosis...

  15. 21 CFR 862.1290 - Fatty acids test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Fatty acids test system. 862.1290 Section 862.1290....1290 Fatty acids test system. (a) Identification. A fatty acids test system is a device intended to measure fatty acids in plasma and serum. Measurements of fatty acids are used in the diagnosis...

  16. Electromagnetic Scale Models Using Emulsions

    DTIC Science & Technology

    1989-04-01

    microwave range; the solutions have a nearly constant permittivity and a conductivity that is adjustable by varying the salt concentration. Mixtures of...emulsion. At this point, complete demulsification has occurred. The emulsion can then be reformed only by subjecting it to the process (homogenization...130-137, June 1986. [17] A. Stogryn, "Equations for calculating the dielectric constant of saline water," IEEE Trans. Microwave Theory and Tech

  17. The Effect of Fish Oil-Based Lipid Emulsion and Soybean Oil-Based Lipid Emulsion on Cholestasis Associated with Long-Term Parenteral Nutrition in Premature Infants

    PubMed Central

    Wang, Leilei; Zhang, Jing; Gao, Jiejin; Qian, Yan; Ling, Ya

    2016-01-01

    Purpose. To retrospectively study the effect of fish oil-based lipid emulsion and soybean oil-based lipid emulsion on cholestasis associated with long-term parenteral nutrition in premature infants. Methods. Soybean oil-based lipid emulsion and fish oil-based lipid emulsion had been applied in our neonatology department clinically between 2010 and 2014. There were 61 qualified premature infants included in this study and divided into two groups. Soybean oil group was made up of 32 premature infants, while fish oil group was made up of 29 premature infants. Analysis was made on the gender, feeding intolerance, infection history, birth weight, gestational age, duration of parenteral nutrition, total dosage of amino acid, age at which feeding began, usage of lipid emulsions, and incidence of cholestasis between the two groups. Results. There were no statistical differences in terms of gender, feeding intolerance, infection history, birth weight, gestational age, duration of parenteral nutrition, total dosage of amino acid, and age at which feeding began. Besides, total incidence of cholestasis was 21.3%, and the days of life of occurrence of cholestasis were 53 ± 5.0 days. Incidence of cholestasis had no statistical difference in the two groups. Conclusion. This study did not find the different role of fish oil-based lipid emulsions and soybean oil-based lipid emulsions in cholestasis associated with long-term parenteral nutrition in premature infants. PMID:27110237

  18. Fat emulsion for intravenous administration: clinical experience with intralipid 10%.

    PubMed Central

    Hansen, L M; Hardie, B S; Hidalgo, J

    1976-01-01

    A 10% soybean oil emulsion (Intralipid 10%), used extensively in Europe for intravenous alimentation, has now been clinically evaluated in the United States. Controlled studies have shown that the soybean oil emulsion can be substituted for glucose to supply one-third to two-thirds of the total calories, and can be administered peripherally without significant vein irritation. Essential fatty acid deficiencies, frequently encountered in patients dependent on parenteral alimentation with fat-free solutions, are prevented and corrected by use of this preparation. Data on long-term tolerance to Intralipid 10% infusions are presented for 292 patients treated for more than 6,000 patient days. The soybean oil emulsion was usually well tolerated. Side effects were reported in two of 133 adults and 12 of 159 pediatric patients. PMID:820291

  19. Formulation and physicochemical properties of macro- and microemulsions prepared by interfacial ion-pair formation between amino acids and fatty acids

    SciTech Connect

    Woo, G.T.P.

    1987-01-01

    Emulsions were prepared by dissolving an amino acid in the aqueous phase and a fatty acid in the oil phase of the emulsions. When the two phases were mixed, the amino acid and fatty acid formed an ion pair at the oil-water interface which stabilized one phase as small droplets within the other to give a stable emulsion. NMR spectra indicated protonation on the amino groups when a carboxylic acid was added to an aqueous solution of an amino acid. Various hydrocarbons and mineral oil could be emulsified into oil-in-water emulsions with a high volume ratio containing up to 75% internal oil phase. Vegetable oils such as soybean oil, safflower seed oil and cottonseed oil were emulsified to a lesser extent. Both oil-in-water and water-in-oil emulsions could be formed with the same emulsifying agents depending on the phase volume ratio and the order of addition of oil phase to water phase or the reverse. Particle size measurements using laser light-scattering techniques indicated an oil-in-water emulsion mixed by a magnetic stirring bar had an internal droplet size in the range of 0.1 to 0.3 micron. Such emulsions were stable at 50/degrees/ and 60/degrees/C for three to six months. In addition to the macroemulsions described above, completely clear water-in-oil microemulsions can be prepared from the above systems by the addition of long-chain fatty alcohols such as oleyl alcohol. Clear regions of such clear microemulsions were characterized. Microemulsion systems suitable for tertiary oil recovery were also studied. Clear microemulsions prepared by ion-pairing between ammonia and hexanoic acid could contain octane or tetradecane in the form of oil-in-water or water-in-oil microemulsions at a wide range of oil to aqueous ratio.

  20. Influence of formulation on the oxidative stability of water-in-oil emulsions.

    PubMed

    Dridi, Wafa; Essafi, Wafa; Gargouri, Mohamed; Leal-Calderon, Fernando; Cansell, Maud

    2016-07-01

    The oxidation of water-in-oil (W/O) emulsions was investigated, emphasizing the impact of compositional parameters. The emulsions had approximately the same average droplet size and did not show any physical destabilization throughout the study. In the absence of pro-oxidant ions in the aqueous phase, lipid oxidation of the W/O emulsions was moderate at 60°C and was in the same range as that measured for the neat oils. Oxidation was significantly promoted by iron encapsulation in the aqueous phase, even at 25°C. However, iron chelation reduced the oxidation rate. Emulsions based on triglycerides rich in polyunsaturated fatty acids were more prone to oxidation, whether the aqueous phase encapsulated iron or not. The emulsions were stabilized by high- and low-molecular weight surfactants. Increased relative fractions of high molecular weight components reduced the oxidation rate when iron was present.

  1. Insecticidal activity of caffeine aqueous solutions and caffeine oleate emulsions against Drosophila melanogaster and Hypothenemus hampei.

    PubMed

    Araque, Pedronel; Casanova, Herley; Ortiz, Carlos; Henao, Beatriz; Pelaez, Carlos

    2007-08-22

    The bioactivity of caffeine aqueous solutions (0.20-2.00 wt %) and caffeine oleate emulsions (20 vol % oil, 2.00 wt % surfactant, 0.04 wt % caffeine, 0.05 wt % oleic acid) was assessed against two biological models: Drosophila melanogaster and Hypothenemus hampei. The caffeine aqueous solutions showed no insecticidal activity, whereas caffeine oleate emulsions had high bioactivity against both D. melanogaster and H. hampei. By preparing the caffeine oleate emulsions with anionic surfactants (i.e., sodium lauryl sulfate, sodium laureate, and sodium oleate), we obtained a lethal time 50 (LT50) of 23 min. In the case of caffeine oleate emulsions prepared with nonionic surfactants (i.e., Tween 20 and Tween 80), a LT50 of approximately 17 min was observed. The high bioactivity of the caffeine oleate emulsion against H. hampei opens the possibility of using this insecticide formulation as an effective way to control this pest that greatly affects coffee plantations around the world.

  2. Innovative Applications Of Food Related Emulsions.

    PubMed

    S, Kiokias; T, Varzakas

    2016-02-06

    Research on oxidative stability of multiple emulsions is very scarce. Given that this is a relevant topic that must be ascertained before the successful application of multiple emulsions in foods (especially when a combination of highly unsaturated oils is used as a lipid phase), this review mainly focus on various aspects of the multiple emulsions. Fat replacement in meat products using emulsions is critically discussed along with innovative applications of natural antioxidants in food based emulsions and multiple emulsions based on bioactive compounds/encapsulation as well as confectionery products.

  3. 21 CFR 862.1795 - Vanilmandelic acid test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vanilmandelic acid test system. 862.1795 Section... Systems § 862.1795 Vanilmandelic acid test system. (a) Identification. A vanilmandelic acid test system is a device intended to measure vanilmandelic acid in urine. Measurements of vanilmandelic...

  4. 21 CFR 862.1795 - Vanilmandelic acid test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vanilmandelic acid test system. 862.1795 Section... Systems § 862.1795 Vanilmandelic acid test system. (a) Identification. A vanilmandelic acid test system is a device intended to measure vanilmandelic acid in urine. Measurements of vanilmandelic...

  5. A double-emulsion microfluidic platform for in vitro green fluorescent protein expression

    NASA Astrophysics Data System (ADS)

    Wu, N.; Oakeshott, J. G.; Easton, C. J.; Peat, T. S.; Surjadi, R.; Zhu, Y.

    2011-05-01

    Microfluidic droplet technology has gained popularity due to the advantages over conventional emulsion techniques and capabilities for a wide range of applications. In this paper, the development of a simple microfluidic-based double-emulsion system is reported. Such a system could be potentially used for in vitro protein synthesis. The system involves a two-step process to make water-in-oil-in-water (W/O/W) emulsions. A PMMA microchip is used for the formation of water-in-oil (W/O) single-emulsion droplets. Then, the single-emulsion droplets are transported to a PDMS/glass microchip to make the W/O/W double-emulsion droplets. The system was first characterized by detecting fluorescein sodium salt as a model dye in the internal aqueous droplets using laser-induced fluorescence. The effect of the flow rates of the internal aqueous phase and outer continuous aqueous phase on the formation of the double-emulsion droplets is investigated to provide information for system optimization. On-chip storage of double-emulsion droplets is also investigated to allow for protein synthesis from a PCR-generated DNA template using either commercial in vitro transcription and translation kits or crude Escherichia coli S30 extracts. In vitro expression of the green fluorescent protein is successfully demonstrated in this system.

  6. Enhancing oral bioavailability using preparations of apigenin-loaded W/O/W emulsions: In vitro and in vivo evaluations.

    PubMed

    Kim, Bum-Keun; Cho, Ah-Ra; Park, Dong-June

    2016-09-01

    We analyzed the physical properties and digestibility of apigenin-loaded emulsions as they passed through a simulated digestion model. As the emulsion passed through the simulated stages of digestion, the particle size and zeta potential of all the samples changed, except for the soybean oil-Tween 80 emulsion, in which zeta potential remained constant, through all stages, indicating that soybean oil-Tween 80 emulsions may have an effect on stability during all stages of digestion. Fluorescence microscopy was used to observe the morphology of the emulsions at each step. The in vivo pharmacokinetics revealed that apigenin-loaded soybean oil-Tween 80 emulsions had a higher oral bioavailability than did the orally administrated apigenin suspensions. These results suggest that W/O/W multiple emulsions formulated with soybean oil and tween 80 have great potential as targeted delivery systems for apigenin, and may enhance in vitro and in vivo bioavailability when they pass through the digestive tract.

  7. Antioxidant protective effect of flavonoids on linoleic acid peroxidation induced by copper(II)/ascorbic acid system.

    PubMed

    Beker, Bilge Yıldoğan; Bakır, Temelkan; Sönmezoğlu, Inci; Imer, Filiz; Apak, Reşat

    2011-11-01

    Antioxidants are compounds that can delay or inhibit lipid oxidation. The peroxidation of linoleic acid (LA) in the absence and presence of Cu(II) ion-ascorbate combinations was investigated in aerated and incubated emulsions at 37°C and pH 7. LA peroxidation induced by copper(II)-ascorbic acid system followed first order kinetics with respect to hydroperoxides concentration. The extent of copper-initiated peroxide production in a LA system assayed by ferric thiocyanate method was used to determine possible antioxidant and prooxidant activities of the added flavonoids. The effects of three different flavonoids of similar structure, i.e. quercetin (QR), morin (MR) and catechin (CT), as potential antioxidant protectors were studied in the selected peroxidation system. The inhibitive order of flavonoids in the protection of LA peroxidation was: morin>catechin≥quercetin, i.e. agreeing with that of formal reduction potentials versus NHE at pH 7, i.e. 0.60, 0.57 and 0.33V for MR, CT, and QR, respectively. Morin showed antioxidant effect at all concentrations whereas catechin and quercetin showed both antioxidant and prooxidant effects depending on their concentrations. The structural requirements for antioxidant activity in flavonoids interestingly coincide with those for Cu(II)-induced prooxidant activity, because as the reducing power of a flavonoid increases, Cu(II)-Cu(I) reduction is facilitated that may end up with the production of reactive species. The findings of this study were evaluated in the light of structure-activity relationships of flavonoids, and the results are believed to be useful to better understand the actual conditions where flavonoids may act as prooxidants in the preservation of heterogeneous food samples containing traces of transition metal ions.

  8. Uric Acid Nephrolithiasis: A Systemic Metabolic Disorder

    PubMed Central

    Moe, Orson W.

    2014-01-01

    Uric acid nephrolithiasis is characteristically a manifestation of a systemic metabolic disorder. It has a prevalence of about 10% among all stone formers, the third most common type of kidney stone in the industrialized world. Uric acid stones form primarily due to an unduly acid urine; less deciding factors are hyperuricosuria and a low urine volume. The vast majority of uric acid stone formers have the metabolic syndrome, and not infrequently, clinical gout is present as well. A universal finding is a low baseline urine pH plus insufficient production of urinary ammonium buffer. Persons with gastrointestinal disorders, in particular chronic diarrhea or ostomies, and patients with malignancies with a large tumor mass and high cell turnover comprise a less common but nevertheless important subset. Pure uric acid stones are radiolucent but well visualized on renal ultrasound. A 24 h urine collection for stone risk analysis provides essential insight into the pathophysiology of stone formation and may guide therapy. Management includes a liberal fluid intake and dietary modification. Potassium citrate to alkalinize the urine to a goal pH between 6 and 6.5 is essential, as undissociated uric acid deprotonates into its much more soluble urate form. PMID:25045326

  9. Interfacial Concentrations of Hydroxytyrosol and Its Lipophilic Esters in Intact Olive Oil-in-Water Emulsions: Effects of Antioxidant Hydrophobicity, Surfactant Concentration, and the Oil-to-Water Ratio on the Oxidative Stability of the Emulsions.

    PubMed

    Almeida, João; Losada-Barreiro, Sonia; Costa, Marlene; Paiva-Martins, Fátima; Bravo-Díaz, Carlos; Romsted, Laurence S

    2016-06-29

    We determined the interfacial molarities of the antioxidants, AOs, hydroxytyrosol (HT), and HT fatty acid esters with chain lengths of 1 to 16 carbons in intact olive oil/water/Tween 20 emulsions. The results were compared with chain length effects on the oxidative stability of the same emulsions, and a direct correlation was established. Both (AOI) molarities (varying 50-250 times greater than the stoichiometric 3.5 × 10(-3) M AO concentration) and antioxidant efficiencies show similar parabola-like dependences on AO chain length with a maximum at C8, consistent with the "cut-off" effect often observed at longer chain lengths. Results should aid in understanding the complex structure-reactivity relationships between AO efficiencies in emulsified systems and their hydrophobilic-hydrophobic balance.

  10. Starch-based Pickering emulsions for topical drug delivery: A QbD approach.

    PubMed

    Marto, J; Gouveia, L; Jorge, I M; Duarte, A; Gonçalves, L M; Silva, S M C; Antunes, F; Pais, A A C C; Oliveira, E; Almeida, A J; Ribeiro, H M

    2015-11-01

    Pickering emulsions are stabilized by solid particles instead of surfactants and have been widely investigated in pharmaceutical and cosmetic fields since they present less adverse effects than the classical emulsions. A quality by design (QbD) approach was applied to the production of w/o emulsions stabilized by starch. A screening design was conducted to identify the critical variables of the formula and the process affecting the critical quality properties of the emulsion (droplet size distribution). The optimization was made by establishing the Design Space, adjusting the concentration of starch and the quantity of the internal aqueous phase. The emulsion production process was, in turn, adjusted by varying the time and speed of stirring, to ensure quality and minimum variability. The stability was also investigated, demonstrating that an increase in starch concentration improves the stability of the emulsion. Rheological and mechanical studies indicated that the viscosity of the emulsions was enhanced by the addition of starch and, to a higher extent, by the presence of different lipids. The developed formulations was considered non-irritant, by an in vitro assay using human cells from skin (Df and HaCat) with the cell viability higher than 90% and, with self-preserving properties. Finally, the QbD approach successfully built quality in Pickering emulsions, allowing the development of hydrophilic drug-loaded emulsions stabilized by starch with desired organoleptic and structural characteristics. The results obtained suggest that these systems are a promising vehicle to be used in products for topical administration.

  11. Formulation parameters influencing the physicochemical characteristics of rosiglitazone-loaded cationic lipid emulsion.

    PubMed

    Davaa, Enkhzaya; Park, Jeong-Sook

    2012-07-01

    To enhance the solubility of rosiglitazone, rosiglitazone-loaded cationic lipid emulsion was formulated using cationic lipid DOTAP, DOPE, castor oil, tween 20, and tween 80. The formulation parameters in terms of droplet size were optimized focused on the effect of the cationic lipid emulsion composition ratio on drug encapsulating efficiency, in vitro drug release, and cellular uptake of the rosiglitazone-loaded emulsion. Droplet sizes of a blank cationic emulsion and a rosiglitazone-loaded cationic emulsion ranged between 195-230 nm and 210-290 nm, respectively. The encapsulation efficiency of the rosiglitazone-loaded emulsion was more than 90%. The rosiglitazone-loaded cationic emulsion improved in vitro drug release over the drug alone and showed a much higher cellular uptake than rosiglitazone alone. Moreover, drug loading in cationic emulsions increased cellular uptake of rosiglitazone in insulin-resistant HepG2 cells more than the normal HepG2 cells. Taken together, these results indicate that cationic lipid emulsions could be a potential delivery system for rosiglitazone and could enhance its cellular uptake efficiency into target cells.

  12. Sub-micron alignment for nuclear emulsion plates using low energy electrons caused by radioactive isotopes

    NASA Astrophysics Data System (ADS)

    Miyamoto, S.; Ariga, A.; Fukuda, T.; Kazuyama, M.; Komatsu, M.; Nakano, T.; Niwa, K.; Sato, O.; Takahashi, S.

    2007-06-01

    Nuclear emulsion plates are employed in three-dimensional charged particle detectors that have sub-micron position resolution over 1 m2 with no dead space and no dead time. These detectors are suitable for the study of short-lived particle decays, and direct detection of neutrino interactions of all flavors. Typically emulsion plates are used in a stacked structure. Precise alignment between plates is required for physics analysis. The most accurate alignment method is to use tracks passing through the emulsion plates. The accuracy is about 0.2 μm. However, in an experiment with low track density alignment accuracy decreases to 20 μm because of plate distortion and it becomes more difficult to perform the analysis. This paper describes a new alignment method between emulsion plates by using trajectories of low energy electrons originating from environmental radioactive isotopes. As a trial emulsion plates were exposed to β-rays and γ-rays from K40. The trajectories which passed through emulsion layers were detected by a fully automated emulsion readout system. Using this method, the alignment between emulsion plates is demonstrated to be sub-micron. This method can be applied to many nuclear emulsion experiments. For example, the location of neutrino interaction vertices in the OPERA experiment can benefit from this new technique.

  13. Acid mine water aeration and treatment system

    DOEpatents

    Ackman, Terry E.; Place, John M.

    1987-01-01

    An in-line system is provided for treating acid mine drainage which basically comprises the combination of a jet pump (or pumps) and a static mixer. The jet pump entrains air into the acid waste water using a Venturi effect so as to provide aeration of the waste water while further aeration is provided by the helical vanes of the static mixer. A neutralizing agent is injected into the suction chamber of the jet pump and the static mixer is formed by plural sections offset by 90 degrees.

  14. Effect of lipophilization of hydroxytyrosol on its antioxidant activity in fish oils and fish oil-in-water emulsions.

    PubMed

    Medina, I; Lois, S; Alcántara, D; Lucas, R; Morales, J C

    2009-10-28

    The effect of lipophilization of the antioxidant efficiency of hydroxytyrosol on fish oil enriched systems was studied. Hydroxytyrosol fatty acid esters with increasing size of the alkyl chain and different lipophilicity were tested in bulk fish oils and fish oil-in-water emulsions. Results showed a significant antioxidant activity of hydroxytyrosol esters in both systems especially in emulsions. The introduction of a lipophilic chain decreased the antioxidant effectiveness of hydroxytyrosol in homogeneous systems as fish oils. In emulsion systems, the presence of a short-medium lipophilic chain (acetate, butyrate or octanoate) improved the antioxidant efficiency of hydroxytyrosol favoring the physical location of the antioxidant in the interface, but longer alkyl chain (laurate) maintained or even decreased their antioxidant activity. A maximum of antioxidant efficiency seems to appear when the chain length of the hydroxytyrosol derivative is that of eight carbons which is probably associated with a preferential location of the diorthophenolic moiety in the right geometry. These results are of high importance for the optimum design of effective antioxidants for omega 3 enriched foods, which are very susceptible to suffer oxidation and, then, rancidity.

  15. Optimizing organoclay stabilized Pickering emulsions.

    PubMed

    Cui, Yannan; Threlfall, Mhairi; van Duijneveldt, Jeroen S

    2011-04-15

    Oil-in-water emulsions were prepared using montmorillonite clay platelets, pre-treated with quaternary amine surfactants. In previous work, cetyl trimethylammonium bromide (CTAB) has been used. In this study, two more hydrophilic quaternary amine surfactants, Berol R648 and Ethoquad C/12, were used and formed Pickering emulsions, which were more stable than the emulsions prepared using CTAB coated clay. The droplets were also more mono-disperse. The most hydrophilic surfactant Berol R648 stabilizes the emulsions best. Salt also plays an important role in forming a stable emulsion. The droplet size decreases with surfactant concentration and relatively mono-disperse droplets can be obtained at moderate surfactant concentrations. The time evolution of the droplet size indicates a good stability to coalescence in the presence of Berol R648. Using polarizing microscopy, the clay platelets were found to be lying flat at the water oil interface. However, a significant fraction (about 90%) of clay stayed in the water phase and the clay particles at the water-oil interface formed stacks, each consisting of four clay platelets on average.

  16. Can Pickering emulsion formation aid the removal of creosote DNAPL from porous media?

    PubMed

    Torres, Luis; Iturbe, Rosario; Snowden, M J; Chowdhry, Babur; Leharne, Stephen

    2008-03-01

    The purpose of this investigation was to examine the proposition that creosote, emplaced in an initially water saturated porous system, can be removed from the system through Pickering emulsion formation. Pickering emulsions are dispersions of two immiscible fluids in which coalescence of the dispersed phase droplets is hindered by the presence of colloidal particles adsorbed at the interface between the two immiscible fluid phases. Particle trapping is strongly favoured when the wetting properties of the particles are intermediate between strong water wetting and strong oil wetting. In this investigation the necessary chemical conditions for the formation of physically stable creosote-in-water emulsions protected against coalescence by bentonite particles were examined. It was established that physically stable emulsions could be formed through the judicious addition of small amounts of sodium chloride and the surfactant cetyl-trimethylammonium bromide. The stability of the emulsions was initially established by visual inspection. However, experimental determinations of emulsion stability were also undertaken by use of oscillatory rheology. Measurements of the elastic and viscous responses to shear indicated that physically stable emulsions were obtained when the viscoelastic systems showed a predominantly elastic response to shearing. Once the conditions were established for the formation of physically stable emulsions a "proof-of-concept" chromatographic experiment was carried out which showed that creosote could be successfully removed from a saturated model porous system.

  17. Impact of new-generation parenteral lipid emulsions in pediatric nutrition.

    PubMed

    Abrams, Steven A

    2013-09-01

    Advancements in the care of premature infants and infants with severe bowel disease have occurred in which long-term use of i.v. nutrition is a cornerstone of successful therapy. Concern about the role of i.v. lipid emulsions in causing severe liver damage to high-risk infants receiving long-term i.v. nutrition has led to a variety of intervention strategies. These have had relatively limited success until the recent introduction of omega-3 (n-3) fatty acid-containing forms of lipid emulsions in place of the current omega-6 fatty acid-predominant lipid emulsions currently exclusively used in the United States. Preliminary data based on nonrandomized trials performed using compassionate-use protocols in the United States suggest very high rates of resolution of cholestasis with the use of an omega-3 fatty acid-predominant lipid emulsion. This result is supported by animal models of liver disease that demonstrate decreased liver damage when animals are provided omega-3 fatty acid-containing lipid emulsions compared with those primarily omega-6 fatty acid based. However, human trials are limited at this time and further research is needed to establish the best approach to preventing liver damage in infants receiving i.v. nutrition and the optimal dose and timing of intervention with novel lipid emulsions.

  18. Effects of trans-4-(aminomethyl) cyclohexanecarboxylic acid/potassium azeloyl diglycinate/niacinamide topical emulsion in Thai adults with melasma: a single-center, randomized, double-blind, controlled study

    PubMed Central

    Viyoch, Jarupa; Tengamnuay, Isaree; Phetdee, Khemjira; Tuntijarukorn, Punpimol; Waranuch, Neti

    2010-01-01

    Background: Melasma is an acquired hyperpigmentary disorder characterized by dark patches or macules located on the cheeks, forehead, upper lip, chin, and neck. Treatment of melasma involves the use of topical hypopigmenting agents such as hydroquinone, tretinoin, and azelaic acid and its derivatives. Objective: The purpose of this study was to assess the efficacy of a formulation containing a combination of trans-4-(aminomethyl) cyclohexanecarboxylic acid/potassium azeloyl diglycinate/niacinamide compared with an emulsion-based control in the treatment of melasma in Thai adults. Methods: In this single-center, randomized, double-blind, controlled study, Thai patients with mild to moderate facial melasma (relative melanin value [RMV] in range of 20–120) were randomized for the application of either the test or the emulsion-based (control) product in the morning and before bedtime for 8 weeks. The supplemental sunscreen product with sun protection factor 30 was distributed to all patients. Subjects were assessed for the intensity of their hyperpigmented skin area by measuring the difference in the absolute melanin value between hyperpigmented skin and normal skin (RMV). This parameter was used as a primary outcome of this study. Additionally, the severity of melasma was determined visually using the Melasma Area and Severity Index (MASI) scored independently by 3 investigators. The assessments of melasma intensity and other skin properties were performed before administration (week 0) and every 2 weeks thereafter for up to 8 weeks. Other skin properties, including moisture content, pH, and redness (erythema value), were measured. Adverse events (AEs), including erythema, scaling, and edema, were also assessed by a dermatologist using the visual grading scale of Frosch and Kligman and COLIPA. Results: The resulting primary intent-to-treat (ITT) population included 33 patients in the test group and 34 patients in the control group. Sixty patients completed all 8

  19. 21 CFR 862.1655 - Pyruvic acid test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Pyruvic acid test system. 862.1655 Section 862....1655 Pyruvic acid test system. (a) Identification. A pyruvic acid test system is a device intended to measure pyruvic acid (an intermediate compound in the metabolism of carbohydrate) in plasma....

  20. 21 CFR 862.1095 - Ascorbic acid test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ascorbic acid test system. 862.1095 Section 862....1095 Ascorbic acid test system. (a) Identification. An ascorbic acid test system is a device intended to measure the level of ascorbic acid (vitamin C) in plasma, serum, and urine. Ascorbic...

  1. 21 CFR 862.1775 - Uric acid test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Uric acid test system. 862.1775 Section 862.1775....1775 Uric acid test system. (a) Identification. A uric acid test system is a device intended to measure uric acid in serum, plasma, and urine. Measurements obtained by this device are used in the...

  2. 21 CFR 862.1775 - Uric acid test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Uric acid test system. 862.1775 Section 862.1775....1775 Uric acid test system. (a) Identification. A uric acid test system is a device intended to measure uric acid in serum, plasma, and urine. Measurements obtained by this device are used in the...

  3. 21 CFR 862.1655 - Pyruvic acid test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pyruvic acid test system. 862.1655 Section 862....1655 Pyruvic acid test system. (a) Identification. A pyruvic acid test system is a device intended to measure pyruvic acid (an intermediate compound in the metabolism of carbohydrate) in plasma....

  4. 21 CFR 862.1095 - Ascorbic acid test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ascorbic acid test system. 862.1095 Section 862....1095 Ascorbic acid test system. (a) Identification. An ascorbic acid test system is a device intended to measure the level of ascorbic acid (vitamin C) in plasma, serum, and urine. Ascorbic...

  5. Multiwalled Carbon Nanotubes at the Interface of Pickering Emulsions.

    PubMed

    Briggs, Nicholas M; Weston, Javen S; Li, Brian; Venkataramani, Deepika; Aichele, Clint P; Harwell, Jeffrey H; Crossley, Steven P

    2015-12-08

    Carbon nanotubes exhibit very unique properties in biphasic systems. Their interparticle attraction leads to reduced droplet coalescence rates and corresponding improvements in emulsion stability. Here we use covalent and noncovalent techniques to modify the hydrophilicity of multiwalled carbon nanotubes (MWCNTs) and study their resulting behavior at an oil-water interface. By using both paraffin wax/water and dodecane/water systems, the thickness of the layer of MWNTs at the interface and resulting emulsion stability are shown to vary significantly with the approach used to modify the MWNTs. Increased hydrophilicity of the MWNTs shifts the emulsions from water-in-oil to oil-in-water. The stability of the emulsion is found to correlate with the thickness of nanotubes populating the oil-water interface and relative strength of the carbon nanotube network. The addition of a surfactant decreases the thickness of nanotubes at the interface and enhances the overall interfacial area stabilized at the expense of increased droplet coalescence rates. To the best of our knowledge, this is the first time the interfacial thickness of modified carbon nanotubes has been quantified and correlated to emulsion stability.

  6. Structure and rheology of highly concentrated emulsions: a modern look

    NASA Astrophysics Data System (ADS)

    Malkin, A. Ya; Kulichikhin, V. G.

    2015-08-01

    The review concerns modern physicochemical, chemical and physical approaches to research into structural features that determine the rheological properties of highly concentrated emulsions. The structures and properties of various systems (suspensions, emulsions as well as transient forms including micellar colloidal solutions) are considered. The formation of highly concentrated emulsions is treated as the concentration glass transition leading to suppression of the molecular and supermolecular mobility and, subsequently, to the existence of a solid-like state of the systems in question. The emphasis is placed on analysis of visco-plasticity which manifests itself in the possibility for emulsions (unlike suspensions) to undergo irreversible deformation (to flow) at stresses exceeding some threshold (critical value) called the yield stress. The thixotropic nature of the transition through the yield stress, governed by the kinetics of the breakup/recovery of the inherent structure is considered in detail. It has been shown that structure formation in highly concentrated emulsions can extend to a macroscopic level and result in the onset of heterogeneity of a flow in the form of shear bands. The bibliography includes 202 references.

  7. Automated Track Recognition and Event Reconstruction in Nuclear Emulsion

    NASA Technical Reports Server (NTRS)

    Deines-Jones, P.; Cherry, M. L.; Dabrowska, A.; Holynski, R.; Jones, W. V.; Kolganova, E. D.; Kudzia, D.; Nilsen, B. S.; Olszewski, A.; Pozharova, E. A.; Sengupta, K.; Szarska, M.; Trzupek, A.; Waddington, C, J.; Wefel, J. P.; Wilczynska, B.; Wilczynski, H.; Wolter, W.; Wosiek, B.; Wozniak, K.

    1998-01-01

    The major advantages of nuclear emulsion for detecting charged particles are its submicron position resolution and sensitivity to minimum ionizing particles. These must be balanced, however, against the difficult manual microscope measurement by skilled observers required for the analysis. We have developed an automated system to acquire and analyze the microscope images from emulsion chambers. Each emulsion plate is analyzed independently, allowing coincidence techniques to be used in order to reject back- ground and estimate error rates. The system has been used to analyze a sample of high-multiplicity Pb-Pb interactions (charged particle multiplicities approx. 1100) produced by the 158 GeV/c per nucleon Pb-208 beam at CERN. Automatically reconstructed track lists agree with our best manual measurements to 3%. We describe the image analysis and track reconstruction techniques, and discuss the measurement and reconstruction uncertainties.

  8. Effects of emulsion gels containing bioactive compounds on sensorial, technological, and structural properties of frankfurters.

    PubMed

    Pintado, T; Herrero, A M; Ruiz-Capillas, C; Triki, M; Carmona, P; Jiménez-Colmenero, F

    2016-03-01

    Emulsion gels prepared with olive oil, chia, and cold gelling agents (transglutaminase, alginate, or gelatin) were used as fat replacers in reduced-fat frankfurter formulation. Nutritional advantages, sensory analysis, technological properties, and microbiological populations of frankfurters were evaluated along with their lipid structural characteristics over chilled storage. Frankfurters with emulsion gels showed significant improvements in fat content (lower saturated fatty acid, higher mono- and polyunsaturated fatty acid contents) and had good fat and water-binding properties. The presence of an emulsion gel reduced lightness and redness, but increased yellowness. Textural behavior of samples was significantly affected by the presence of emulsion gels and by storage. Sensory properties were not affected by the incorporation of emulsion gels, and all frankfurters were judged acceptable. Attenuated total reflectance-Fourier transform infrared spectroscopy results showed that samples with emulsion gels involve more lipid-protein interactions. Frankfurters with emulsion gels showed good stability to oxidation during storage and contained lower levels of microorganism than reduced-fat control at 85 days.

  9. Quantification of unadsorbed protein and surfactant emulsifiers in oil-in-water emulsions.

    PubMed

    Berton, Claire; Genot, Claude; Ropers, Marie-Hélène

    2011-02-15

    Unadsorbed emulsifiers affect the physical and chemical behaviour of oil-in-water (O/W) emulsions. A simple methodology to quantify unadsorbed emulsifiers in the aqueous phase of O/W emulsions has been developed. Emulsions were centrifuged and filtered to separate the aqueous phase from the oil droplets and the concentration of unadsorbed emulsifiers in the aqueous phase determined. The quantification of unadsorbed surfactants based on the direct transesterification of their fatty acids was validated for Tween 20, Tween 80, citric acid ester (Citrem), Span 20 and monolauroyl glycerol. To determine unadsorbed proteins, results obtained with Folin-Ciocalteu reagent or UV-spectrophotometry were compared on emulsions stabilized by β-lactoglobulin (BLG), β-casein (BCN) or bovine serum albumin (BSA). The first method gave more accurate results especially during aging of emulsions in oxidative conditions. The whole methodology was applied to emulsions stabilized with single or mixed emulsifiers. This approach enables optimization of emulsion formulations and could be useful to follow changes in the levels of unadsorbed emulsifiers during physical or chemical aging processes.

  10. Lipid emulsions – Guidelines on Parenteral Nutrition, Chapter 6

    PubMed Central

    Adolph, M.; Heller, A. R.; Koch, T.; Koletzko, B.; Kreymann, K. G.; Krohn, K.; Pscheidl, E.; Senkal, M.

    2009-01-01

    The infusion of lipid emulsions allows a high energy supply, facilitates the prevention of high glucose infusion rates and is indispensable for the supply with essential fatty acids. The administration of lipid emulsions is recommended within ≤7 days after starting PN (parenteral nutrition) to avoid deficiency of essential fatty acids. Low-fat PN with a high glucose intake increases the risk of hyperglycaemia. In parenterally fed patients with a tendency to hyperglycaemia, an increase in the lipid-glucose ratio should be considered. In critically ill patients the glucose infusion should not exceed 50% of energy intake. The use of lipid emulsions with a low phospholipid/triglyceride ratio is recommended and should be provided with the usual PN to prevent depletion of essential fatty acids, lower the risk of hyperglycaemia, and prevent hepatic steatosis. Biologically active vitamin E (α-tocopherol) should continuously be administered along with lipid emulsions to reduce lipid peroxidation. Parenteral lipids should provide about 25–40% of the parenteral non-protein energy supply. In certain situations (i.e. critically ill, respiratory insufficiency) a lipid intake of up to 50 or 60% of non-protein energy may be reasonable. The recommended daily dose for parenteral lipids in adults is 0.7–1.3 g triglycerides/kg body weight. Serum triglyceride concentrations should be monitored regularly with dosage reduction at levels >400 mg/dl (>4.6 mmol/l) and interruption of lipid infusion at levels >1000 mg/dl (>11.4 mmol/l). There is little evidence at this time that the choice of different available lipid emulsions affects clinical endpoints. PMID:20049078

  11. 21 CFR 862.1509 - Methylmalonic acid (nonquantitative) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... methylmalonic acid (nonquantitative) test system is a device intended to identify methylmalonic acid in urine. The identification of methylmalonic acid in urine is used in the diagnosis and treatment...

  12. Perfluorochemical emulsions decrease Kupffer cell phagocytosis

    SciTech Connect

    Bottalico, L.A.; Betensky, H.T.; Min, Y.B.; Weinstock, S.B. )

    1991-07-01

    One drawback to using perfluorochemical emulsions as blood substitutes is that perfluorochemical particles are cleared from the blood by the reticuloendothelial system, primarily liver and spleen. The authors measured the impact of two perfluorochemical emulsions on clearance of colloidal carbon (less than 1 microns) and 51Cr-sheep red blood cells (about 8 microns) by the reticuloendothelial system in vivo and in the isolated perfused liver. Male rats were injected with 2 ml/100 gm body wt of Fluosol-DA or Oxypherol-ET for 4 consecutive days. Carbon (1 ml/100 gm body wt) or sheep red blood cells (0.05 ml of 5% vol/vol/100 gm body wt) were then injected intravenously (in vivo) or added to perfusate. Samples were taken at several time points for 1 hr. In the isolated perfused liver, carbon clearance was depressed by 25% 1 day after treatment. Rates returned to control levels by 12 days in Fluosol-DA-treated rats but remained depressed by 67% in Oxypherol-ET-treated rats. Sheep red blood cell (8 microns) clearance was two to five times slower than carbon clearance and depressed by 40% in livers from Fluosol-DA rats 1 day and 12 days after treatment. Added serum did not improve phagocytosis. In vivo carbon clearance remained normal in Fluosol-DA-treated rats but decreased by 74% in Oxypherol-ET-treated rats 1 day after treatment, returning to normal by 12 days. Clearance rates were similar in control rats in vivo and in the perfused liver. They conclude that the isolated perfused liver is a good model to measure liver clearance function. Although low doses of perfluorochemical emulsions may depress Kupffer cell phagocytosis, general reticuloendothelial system function is not significantly compromised.

  13. Delivery of Chlorambucil Using an Acoustically-Triggered, Perfluoropentane Emulsion

    PubMed Central

    Fabiilli, Mario L.; Haworth, Kevin J.; Sebastian, Ian E.; Kripfgans, Oliver D.; Carson, Paul L.; Fowlkes, J. Brian

    2010-01-01

    Ultrasound-mediated delivery systems have mainly focused on microbubble contrast agents as carriers of drugs or genetic material. This study utilizes micron-sized, perfluoropentane (PFP) emulsions as carriers for chlorambucil (CHL), a lipophilic chemotherapeutic. The release of CHL is achieved via acoustic droplet vaporization (ADV), whereby the superheated emulsion is converted into gas bubbles using ultrasound. Emulsions were made using an albumin shell and soybean oil as the CHL carrier. The ratio of the PFP to soybean oil phases in the droplets, as well as the fraction of droplets that vaporize per ultrasound exposure were shown to correlate with droplet diameter. A 60-minute incubation with the CHL-loaded emulsion caused a 46.7% cellular growth inhibition, whereas incubation with the CHL-loaded emulsion that was exposed to ultrasound at 6.3 MHz caused an 84.3% growth inhibition. This difference was statistically significant (p < 0.01), signifying that ADV can be used as a method to substantially enhance drug delivery. PMID:20691925

  14. Induced phase transitions of nanoparticle-stabilized emulsions

    NASA Astrophysics Data System (ADS)

    Frijters, Stefan; Günther, Florian; Harting, Jens

    2013-11-01

    Nanoparticles can stabilize fluid-fluid interfaces over long timescales and are nowadays commonly used, e.g. in emulsions. However, their fundamental properties are as of yet poorly understood. Nanoparticle-stabilized emulsions can exhibit different phases, such as Pickering emulsions or bijels, which can be characterized by their different topologies and rheology. We investigate the effect of various initial conditions on random mixtures of two fluids and nanoparticles - in particular, the final state these systems will reach. For this, we use the well-established 3D lattice Boltzmann method, extended to allow for the added nanoparticles. After the evolution of the emulsions has stopped, we induce transitions from one state to another by gradually changing the wettability of the nanoparticles over time. This changes the preferential local curvature of the interfaces, which strongly affects the global state. We observe strong hysteresis effects because of the energy barrier presented by the necessary massive reordering of the particles. Being able to change emulsion states in situ has potential application possibilities in filtering technology, or creating particle scaffolds.

  15. Effect of inorganic additives on solutions of nonionic surfactants V: Emulsion stability.

    PubMed

    Schott, H; Royce, A E

    1983-12-01

    Electrolytes often break emulsions to which they were added as active ingredients, adjuvants, or impurities. The stability of oil-in-water emulsions containing octoxynol 9 NF as the emulsifier and various added electrolytes was investigated by measuring droplet size, turbidity, and oil separation on storage at various temperatures and in a centrifugal field at 25 degrees. Electrolytes were added to hexadecane emulsions after emulsification (direct addition); alternatively, hexadecane was emulsified in octoxynol 9-electrolyte mixtures (reverse addition). Xylene emulsions were prepared by direct addition only. Hexadecane emulsions containing 0.10% octoxynol 9 were considerably more stable than xylene emulsions containing 0.60% because the surfactant is practically insoluble in hexadecane, but miscible in all proportions with xylene. An emulsifier soluble in the disperse phase as well as the continuous phase evidently forms less stable interfacial films. The electrolytes investigated were sulfuric and hydrochloric acids, magnesium nitrate, and aluminum nitrate, which salt octoxynol 9 in by complexation between its ether groups and their cations; sodium thiocyanate, which salts the surfactant in by destructuring water; and sodium chloride and sodium sulfate, which salt octoxynol 9 out. The addition of these electrolytes at concentrations up to 2 or 3 m to hexadecane emulsions produced fast and extensive creaming, little or no flocculation, no coalescence, and only minor changes in droplet size or turbidity on storage at room temperature. The extent of coalescence during centrifugation was actually reduced by the additives. Such stability is unusual. Droplet size and turbidity depended mainly on octoxynol 9 concentration. The greatest decrease in the former and increase in the latter occurred when the concentration was increased from 0.10 to approximately 0.4%. All emulsions became slightly coarser on storage at 25 degrees. Stability at 50 degrees was impaired by

  16. Separation Properties of Wastewater Containing O/W Emulsion Using Ceramic Microfiltration/Ultrafiltration (MF/UF) Membranes.

    PubMed

    Nakamura, Kazuho; Matsumoto, Kanji

    2013-06-21

    Washing systems using water soluble detergent are used in electrical and mechanical industries and the wastewater containing O/W emulsion are discharged from these systems. Membrane filtration has large potential for the efficient separation of O/W emulsion for reuses of treated water and detergent. The separation properties of O/W emulsions by cross-flow microfiltration and ultrafiltration were studied with ceramic MF and UF membranes. The effects of pore size; applied pressure; cross-flow velocity; and detergent concentration on rejection of O/W emulsion and flux were systematically studied. At the condition achieving complete separation of O/W emulsion the pressure-independent flux was observed and this flux behavior was explained by gel-polarization model. The O/W emulsion tended to permeate through the membrane at the conditions of larger pore size; higher emulsion concentration; and higher pressure. The O/W emulsion could permeate the membrane pore structure by destruction or deformation. These results imply the stability of O/W emulsion in the gel-layer formed on membrane surface play an important role in the separation properties. The O/W emulsion was concentrated by batch cross-flow concentration filtration and the flux decline during the concentration filtration was explained by the gel- polarization model.

  17. Emulsion Droplet Combustion in Microgravity: Water/Heptane Emulsions

    NASA Technical Reports Server (NTRS)

    Avedisian, C. Thomas

    1997-01-01

    This presentation reviews a series of experiments to further examine parametric effects on sooting processes of droplet flames in microgravity. The particular focus is on a fuel droplet emulsified with water, specifically emulsions of n-heptane as the fuel-phase and water as the dispersed phase. Water was selected as the additive because of its anticipated effect on soot formation, and the heptane fuel phase was chosen to theoretically reduce the likelihood of microexplosions because its boiling point is nearly the same as that of water: 100 C for water and 98 C for heptane. The water content was varied while the initial droplet diameter was kept within a small range. The experiments were carried out in microgravity to reduce the effects of buoyancy and to promote spherical symmetry in the burning process. Spherically symmetric droplet burning is a convenient starting point for analysis, but experimental data are difficult to obtain for this situation as evidenced by the fact that no quantitative data have been reported on unsupported emulsion droplet combustion in a convection-free environment. The present study improves upon past work carried out on emulsion droplet combustion in microgravity which employed emulsion droplets suspended from a fiber. The fiber can be instrusive to the emulsion droplet burning process as it can promote coalescence of the dispersed water phase and heterogeneous nucleation on the fiber. Prior work has shown that the presence of water in liquid hydrocarbons can have both beneficial and detrimental effects on the combustion process. Water is known to reduce soot formation and radiation heat transfer to combustor walls Gollahalli (1979) reduce flame temperatures and thereby NOx emissions, and encourage secondary droplet atomization or microexplosion. Water also tends to retard ignition and and promote early extinction. The former effect restricted the range of water volume fractions as discussed below.

  18. 21 CFR 862.1775 - Uric acid test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Uric acid test system. 862.1775 Section 862.1775...) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1775 Uric acid test system. (a) Identification. A uric acid test system is a device intended to...

  19. 21 CFR 862.1775 - Uric acid test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Uric acid test system. 862.1775 Section 862.1775...) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1775 Uric acid test system. (a) Identification. A uric acid test system is a device intended to...

  20. 21 CFR 862.1775 - Uric acid test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Uric acid test system. 862.1775 Section 862.1775...) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1775 Uric acid test system. (a) Identification. A uric acid test system is a device intended to...

  1. High speed automated microtomography of nuclear emulsions and recent application

    NASA Astrophysics Data System (ADS)

    Tioukov, V.; Aleksandrov, A.; Consiglio, L.; De Lellis, G.; Vladymyrov, M.

    2015-12-01

    The development of high-speed automatic scanning systems was the key-factor for massive and successful emulsions application for big neutrino experiments like OPERA. The emulsion detector simplicity, the unprecedented sub-micron spatial resolution and the unique ability to provide intrinsically 3-dimensional spatial information make it a perfect device for short-living particles study, where the event topology should be precisely reconstructed in a 10-100 um scale vertex region. Recently the exceptional technological progress in image processing and automation together with intensive R&D done by Italian and Japanese microscopy groups permit to increase the scanning speed to unbelievable few years ago m2/day scale and so greatly extend the range of the possible applications for emulsion-based detectors to other fields like: medical imaging, directional dark matter search, nuclear physics, geological and industrial applications.

  2. Arrested of coalescence of emulsion droplets of arbitrary size

    NASA Astrophysics Data System (ADS)

    Mbanga, Badel L.; Burke, Christopher; Blair, Donald W.; Atherton, Timothy J.

    2013-03-01

    With applications ranging from food products to cosmetics via targeted drug delivery systems, structured anisotropic colloids provide an efficient way to control the structure, properties and functions of emulsions. When two fluid emulsion droplets are brought in contact, a reduction of the interfacial tension drives their coalescence into a larger droplet of the same total volume and reduced exposed area. This coalescence can be partially or totally hindered by the presence of nano or micron-size particles that coat the interface as in Pickering emulsions. We investigate numerically the dependance of the mechanical stability of these arrested shapes on the particles size, their shape anisotropy, their polydispersity, their interaction with the solvent, and the particle-particle interactions. We discuss structural shape changes that can be induced by tuning the particles interactions after arrest occurs, and provide design parameters for the relevant experiments.

  3. High speed automated microtomography of nuclear emulsions and recent application

    SciTech Connect

    Tioukov, V.; Aleksandrov, A.; Consiglio, L.; De Lellis, G.; Vladymyrov, M.

    2015-12-31

    The development of high-speed automatic scanning systems was the key-factor for massive and successful emulsions application for big neutrino experiments like OPERA. The emulsion detector simplicity, the unprecedented sub-micron spatial resolution and the unique ability to provide intrinsically 3-dimensional spatial information make it a perfect device for short-living particles study, where the event topology should be precisely reconstructed in a 10-100 um scale vertex region. Recently the exceptional technological progress in image processing and automation together with intensive R&D done by Italian and Japanese microscopy groups permit to increase the scanning speed to unbelievable few years ago m{sup 2}/day scale and so greatly extend the range of the possible applications for emulsion-based detectors to other fields like: medical imaging, directional dark matter search, nuclear physics, geological and industrial applications.

  4. Emulsion Chamber Technology Experiment (ECT)

    NASA Technical Reports Server (NTRS)

    Gregory, John C.; Takahashi, Yoshiyuki

    1996-01-01

    The experimental objective of Emulsion Chamber Technology (ECT) was to develop space-borne emulsion chamber technology so that cosmic rays and nuclear interactions may subsequently be studied at extremely high energies with long exposures in space. A small emulsion chamber was built and flown on flight STS-62 of the Columbia in March 1994. Analysis of the several hundred layers of radiation-sensitive material has shown excellent post-flight condition and suitability for cosmic ray physics analysis at much longer exposures. Temperature control of the stack was 20 +/-1 C throughout the active control period and no significant deviations of temperature or pressure in the chamber were observed over the entire mission operations period. The unfortunate flight attitude of the orbiter (almost 90% Earth viewing) prevented any significant number of heavy particles (Z greater than or equal to 10) reaching the stack and the inverted flow of shower particles in the calorimeter has not allowed evaluation of absolute primary cosmic ray-detection efficiency nor of the practical time limits of useful exposure of these calorimeters in space to the level of detail originally planned. Nevertheless, analysis of the observed backgrounds and quality of the processed photographic and plastic materials after the flight show that productive exposures of emulsion chambers are feasible in low orbit for periods of up to one year or longer. The engineering approaches taken in the ECT program were proven effective and no major environmental obstacles to prolonged flight are evident.

  5. Controlling the potential gastrointestinal fate of β-carotene emulsions using interfacial engineering: Impact of coating lipid droplets with polyphenol-protein-carbohydrate conjugate.

    PubMed

    Liu, Fuguo; Ma, Cuicui; Zhang, Ruojie; Gao, Yanxiang; Julian McClements, David

    2017-04-15

    The impact of interfacial coatings comprised of polyphenol-protein-carbohydrate conjugates on the properties of nutraceutical-fortified lipid droplets during digestion was investigated. Surface-active chlorogenic acid-lactoferrin-polydextrose (CA-LF-PD) conjugate was synthesized as emulsifier to stabilize lipid droplets in β-carotene-enriched oil-in-water emulsions. Changes in droplet size, charge, and microstructure were monitored as β-carotene emulsions were passed through a simulated gastrointestinal tract model (mouth, stomach, small intestine). LF-coated droplets were unstable to flocculation at pH 8.0-9.0, due to the reduction in electrostatic repulsion, but CA-LF-PD conjugate-coated droplets were stable. Emulsions stabilized by ternary conjugate had better stability to droplet aggregation under simulated GIT conditions than other systems, which increased β-carotene bioaccessibility. The importance of including an oral phase in the simulated GIT model was also demonstrated. The ternary conjugate-stabilized emulsions developed in this study have potential applications as protectors and carriers of hydrophobic drugs, supplements and nutraceuticals.

  6. Influence of PEG-12 Dimethicone addition on stability and formation of emulsions containing liquid crystal.

    PubMed

    Andrade, F F; Santos, O D H; Oliveira, W P; Rocha-Filho, P A

    2007-06-01

    Oil/water emulsions, containing liquid crystals, were developed employing Andiroba oil, PEG-12 Dimethicone and Crodafos CES. It was evaluated the influence of silicone surfactants on the emulsions stability and on the formation of liquid crystalline phases and therefore, physicochemical characteristics, such as rheology and zeta potential, were evaluated. Emulsions were prepared by the emulsions phase inversion method. All the formulations presented lamellar liquid crystalline phases. The PEG-12 Dimethicone addition did not change microscopically the liquid crystalline phases. The emulsions containing silicone demonstrated lower viscosity than those without the additive. This is an important feature, as the silicone did not change the rheological profile; however, the addition of silicone still can be used as a viscosity controller. The formulations had their viscosity increased 15 and 150 days after their preparation. This characteristic shows that the emulsions have their organization increased along the storing time. In the analysis of zeta potential, we could verify that all formulations presented negative values between -39.7 and -70.0 mV. Within this range of values, the emulsion physical stability is high (Fig. 10). It was concluded that the addition of PEG-12 Dimethicone kept the liquid crystalline phase of the emulsion obtained with Crodafos CES, influencing in a positive way in the system stability.

  7. Detecting plastic events in emulsions simulations

    NASA Astrophysics Data System (ADS)

    Lulli, Matteo; Matteo Lulli, Massimo Bernaschi, Mauro Sbragaglia Team

    2016-11-01

    Emulsions are complex systems which are formed by a number of non-coalescing droplets dispersed in a solvent leading to non-trivial effects in the overall flowing dynamics. Such systems possess a yield stress below which an elastic response to an external forcing occurs, while above the yield stress the system flows as a non-Newtonian fluid, i.e. the stress is not proportional to the shear. In the solid-like regime the network of the droplets interfaces stores the energy coming from the work exerted by an external forcing, which can be used to move the droplets in a non-reversible way, i.e. causing plastic events. The Kinetic-Elasto-Plastic (KEP) theory is an effective theory describing some features of the flowing regime relating the rate of plastic events to a scalar field called fluidity f =γ˙/σ , i.e. the inverse of an effective viscosity. Boundary conditions have a non-trivial role not captured by the KEP description. In this contribution we will compare numerical results against experiments concerning the Poiseuille flow of emulsions in microchannels with complex boundary geometries. Using an efficient computational tool we can show non-trivial results on plastic events for different realizations of the rough boundaries. The research leading to these results has received funding from the European Research Council under the European Community's Seventh Framework Programme (FP7/2007- 2013)/ERC Grant Agreement no. [279004].

  8. Protein-based emulsion electrosprayed micro- and submicroparticles for the encapsulation and stabilization of thermosensitive hydrophobic bioactives.

    PubMed

    Gómez-Mascaraque, Laura G; López-Rubio, Amparo

    2016-03-01

    This work shows the potential of emulsion electrospraying of proteins using food-grade emulsions for the microencapsulation and enhanced protection of a model thermosensitive hydrophobic bioactive. Specifically, gelatin, a whey protein concentrate (WPC) and a soy protein isolate (SPI) were compared as emulsion stabilizers and wall matrices for encapsulation of α-linolenic acid. In a preliminary stage, soy bean oil was used as the hydrophobic component for the implementation of the emulsion electrospraying process, investigating the effect of protein type and emulsion protocol used (i.e. with or without ultrasound treatment) on colloidal stability. This oil was then substituted by the ω-3 fatty acid and the emulsions were processed by electrospraying and spray-drying, comparing both techniques. While the latter resulted in massive bioactive degradation, electrospraying proved to be a suitable alternative, achieving microencapsulation efficiencies (MEE) of up to ∼70%. Although gelatin yielded low MEEs due to the need of employing acetic acid for its processing by electrospraying, SPI and WPC achieved MEEs over 60% for the non-sonicated emulsions. Moreover, the degradation of α-linolenic acid at 80°C was significantly delayed when encapsulated within both matrices. Whilst less than an 8% of its alkene groups were detected after 27h of thermal treatment for free α-linolenic acid, up to 43% and 67% still remained intact within the electrosprayed SPI and WPC capsules, respectively.

  9. Effect of Grape Seed Proanthocyanidin-Gelatin Colloidal Complexes on Stability and in Vitro Digestion of Fish Oil Emulsions.

    PubMed

    Su, Yu-Ru; Tsai, Yi-Chin; Hsu, Chun-Hua; Chao, An-Chong; Lin, Cheng-Wei; Tsai, Min-Lang; Mi, Fwu-Long

    2015-11-25

    The colloidal complexes composed of grape seed proanthocyanidin (GSP) and gelatin (GLT), as natural antioxidants to improve stability and inhibit lipid oxidation in menhaden fish oil emulsions, were evaluated. The interactions between GSP and GLT, and the chemical structures of GSP/GLT self-assembled colloidal complexes, were characterized by isothermal titration calorimetry (ITC), circular dichroism (CD), and Fourier transform infrared spectroscopic (FTIR) studies. Fish oil was emulsified with GLT to obtain an oil-in-water (o/w) emulsion. After formation of the emulsion, GLT was fixed by GSP to obtain the GSP/GLT colloidal complexes stabilized fish oil emulsion. Menhaden oil emulsified by GSP/GLT(0.4 wt %) colloidal complexes yielded an emulsion with smaller particles and higher emulsion stability as compared to its GLT emulsified counterpart. The GSP/GLT colloidal complexes inhibited the lipid oxidation in fish oil emulsions more effectively than free GLT because the emulsified fish oil was surrounded by the antioxidant GSP/GLT colloidal complexes. The digestion rate of the fish oil emulsified with the GSP/GLT colloidal complexes was reduced as compared to that emulsified with free GLT. The extent of free fatty acids released from the GSP/GLT complexes stabilized fish oil emulsions was 63.3% under simulated digestion condition, indicating that the fish oil emulsion was considerably hydrolyzed with lipase.

  10. The emulsion chamber technology experiment

    NASA Technical Reports Server (NTRS)

    Gregory, John C.

    1992-01-01

    Photographic emulsion has the unique property of recording tracks of ionizing particles with a spatial precision of 1 micron, while also being capable of deployment over detector areas of square meters or 10's of square meters. Detectors are passive, their cost to fly in Space is a fraction of that of instruments of similar collecting. A major problem in their continued use has been the labor intensiveness of data retrieval by traditional microscope methods. Two factors changing the acceptability of emulsion technology in space are the astronomical costs of flying large electronic instruments such as ionization calorimeters in Space, and the power and low cost of computers, a small revolution in the laboratory microscope data-taking. Our group at UAH made measurements of the high energy composition and spectra of cosmic rays. The Marshall group has also specialized in space radiation dosimetry. Ionization calorimeters, using alternating layers of lead and photographic emulsion, to measure particle energies up to 10(exp 15) eV were developed. Ten balloon flights were performed with them. No such calorimeters have ever flown in orbit. In the ECT program, a small emulsion chamber was developed and will be flown on the Shuttle mission OAST-2 to resolve the principal technological questions concerning space exposures. These include assessments of: (1) pre-flight and orbital exposure to background radiation, including both self-shielding and secondary particle generation; the practical limit to exposure time in space can then be determined; (2) dynamics of stack to optimize design for launch and weightlessness; and (3) thermal and vacuum constraints on emulsion performance. All these effects are cumulative and affect our ability to perform scientific measurements but cannot be adequately predicted by available methods.

  11. Effects of visible and UV light on the characteristics and properties of crude oil-in-water (O/W) emulsions.

    PubMed

    Genuino, Homer C; Horvath, Dayton T; King'ondu, Cecil K; Hoag, George E; Collins, John B; Suib, Steven L

    2012-04-01

    The effects of visible and UV light on the characteristics and properties of Prudhoe Bay (PB) and South Louisiana (SL) emulsions were investigated to better understand the role of sunlight on the fate of spilled crude oils that form emulsions with a dispersant in the aquatic environment. Before irradiation, crude oil emulsions showed the presence of dispersed crude oil micelles in a continuous water phase and crude oil components floating on the surface. The crude oil micelles decreased in size with irradiation, but emulsions retained their high degree of polydispersity. UV irradiation reduced the stability of emulsions more effectively than visible light. The reduction of micelles size caused the viscosity of emulsions to increase and melting point to decrease. Further, irradiation increased acid concentrations and induced ion formation which lowered the pH and increased the conductivity of emulsions, respectively. Ni and Fe in PB emulsions were extracted from crude oil with UV irradiation, which may provide an efficient process for metal removal. The emulsions were stable toward freeze/thaw cycles and their melting temperatures generally decreased with irradiation. Evidence of ˙OH production existed when emulsions were exposed to UV but not to visible light. The presence of H(2)O(2) enhanced the photodegradation of crude oil. Overall, the changes in emulsion properties were attributed to direct photodegradation and photooxidation of crude oil components.

  12. Laboratory Investigations in Support of Carbon Dioxide-in-Water Emulsions Stabilized by Fine Particles for Ocean and Geologic Sequestration of Carbon Dioxide

    SciTech Connect

    Dan Golomb; Eugene Barry; David Ryan

    2006-07-08

    This semi-annual progress report includes our latest research on deep ocean sequestration of CO{sub 2}-in-Water (C/W) emulsions stabilized by pulverized limestone (CaCO{sub 3}). We describe a practical system that could be employed for the release of a dense C/W emulsion. The heart of the system is a Kenics-type static mixer. The testing and evaluation of a static mixer in the NETL High-Pressure Water Tunnel Facility was described in the previous semi-annual report. The release system could be deployed from a floating platform over the open ocean, or at the end of an off-shore pipe laying on the continental slope. Because the emulsion is much denser than ambient seawater, modeling shows that upon release the plume will sink much deeper from the injection point, increasing the sequestration time for CO{sub 2}. When released in the open ocean, a plume containing the output of a 500 MW{sub el} coal-fired power plant will typically sink hundreds of meters below the injection point. When released from a pipe on the continental shelf, the plume will sink about twice as much because of the limited entrainment of ambient seawater when the plume flows along the sloping seabed. Furthermore, the plume is slightly alkaline, not acidic. The disadvantage is that the creation of the emulsion requires significant amounts of pulverized limestone, on the order of 0.5-0.75 weight ratio of limestone to CO{sub 2}. While pulverized limestone with particle size appropriate for creating C/W emulsions can be purchased for $38 per ton, it is shown in this report that it may be more economic to purchase raw limestone from quarries and pulverize it in situ using grinding mills. In this case the major cost elements are the capital and operating costs of the grinding mills, resulting in a total cost of about $11 per ton of pulverized limestone, including the cost of raw material and shipping. Because we need approximately 0.75 ton of pulverized limestone per ton of liquid CO2 to create a stable

  13. Physicochemical behaviour of WPI-stabilized emulsions in in vitro gastric and intestinal conditions.

    PubMed

    Li, Jessie; Ye, Aiqian; Lee, Sung Je; Singh, Harjinder

    2013-11-01

    Most studies on the in vitro lipid digestion of protein-stabilized emulsions have been carried out under simulated gastric and intestinal conditions. In this study, the digestion behaviour of whey protein isolate (WPI)-stabilized emulsions was examined under simulated intestinal fluid (SIF) conditions (pH 7.5, 2.5mg bile salts/mL and 0.8 mg pancreatin/mL) after the emulsions had been digested in a model simulated gastric fluid (SGF) containing pepsin (pH 1.6 and 3.2mg pepsin/mL) for different times. The droplet size, ζ-potential, microstructure, surface protein and amount of free fatty acids released were examined. The results indicated that WPI emulsions did not undergo pronounced changes in droplet size and microstructure during SGF digestion followed by coalescence during the subsequent SIF digestion. When WPI emulsions were treated with SGF, α-lactalbumin and a portion of β-lactoglobulin proteins adsorbed at the interface were hydrolysed by pepsin, resulting in small peptides being produced as characterized by sodium dodecyl sulphate polyacrylamide gel electrophoresis. In general, digestion in SGF containing pepsin accelerated coalescence of the emulsion droplets during subsequent digestion in SIF containing pancreatic lipase. However, the changes in the size, the microstructure and the proteolysis of the interfacial proteins of the emulsions under gastric conditions did not influence the rate and the extent of lipid digestion in the subsequent intestinal environment.

  14. Folate ligand anchored liquid crystal microdroplets emulsion for in vitro detection of KB cancer cells.

    PubMed

    Yoon, Seong H; Gupta, Kailash C; Borah, Jyoti S; Park, Soo-Young; Kim, Young-Kyoo; Lee, Joon-Hyung; Kang, Inn-Kyu

    2014-09-09

    A KB cancer cell-selective, liquid crystal microdroplets emulsion is prepared using folic acid-conjugated block copolymers (PS-b-PAA-FA) and sodium dodecyl sulfate (SDS) as a mediator to induce configurational transitions in 4-cyano-4'-pentylbiphenyl (5CB) liquid crystal microdroplets emulsion. The prepared liquid crystal microdroplets emulsion has shown a configurational transition from radial to bipolar on interacting with KB cancer cells, but no transition from radial to bipolar configuration is observed when liquid crystal microdroplets emulsion was allowed to interact with other normal cells such as fibroblast and osteoblast. The KB cancer cell selectivity of liquid crystal microdroplets emulsion has been considered due to the presence of KB cancer cell folate receptor-specific ligand (FA) at the surface of liquid crystal microdroplets, which allowed liquid crystal microdroplets to interact specifically with KB cancer cells. The ligand-receptor interactions have been considered responsible for triggering the configurational transitions from radial to bipolar in liquid crystal microdroplets emulsion. Thus, folate ligand anchored liquid crystal microdroplets emulsion has shown a potential to be used for in vitro detection of KB cancer cells in the early stage of tumor development.

  15. Effects of intravenous triacylglycerol emulsions on hepatic metabolism and blood metabolites in fasted dairy cows.

    PubMed

    Mashek, D G; Bertics, S J; Grummer, R R

    2005-01-01

    The objective was to determine the effects of intravenous infusion of triacylglycerol (TAG) emulsions derived from different lipid sources on energy metabolism during a 4-d fast. Six nonpregnant, nonlactating multiparous Holstein cows were randomly assigned to treatments in a replicated 3 x 3 Latin Square design. Treatments included intravenous infusion of tallow, linseed oil, or fish oil emulsions at a rate of 0.54 g of TAG/kg of body weight per day; infusions were concurrent with a 4-d fast. The emulsions were administered for 20 to 30 min every 4 h throughout the 4-d fast. Cows were fed ad libitum for 24 d between the fast/infusion periods. Infusion of tallow, linseed oil, or fish oil emulsions increased plasma concentrations of palmitic acid, linolenic acid, and eicosapentaenoic and docosahexaenoic acids, respectively. Infusion of linseed oil emulsion decreased plasma TAG concentrations compared with tallow and fish oil treatments, which were similar. Infusion of the tallow emulsion resulted in the highest concentrations of plasma nonesterified fatty acid (NEFA), insulin, and glucose, whereas the infusion derived from linseed oil had the lowest NEFA and beta-hydroxybutyric acid concentrations. The different TAG emulsions had no effect on total or peroxisomal oxidation of [1-(14C)]oleic acid in liver homogenates. Liver TAG content increased 12.0, 7.8, and 14.1 microg/microg of DNA during the fast for tallow, linseed oil, and fish oil treatments, respectively; linseed oil was different from fish oil and tended to be different from tallow.

  16. Oil-in-Water Emulsion Exhibits Bitterness-Suppressing Effects in a Sensory Threshold Study.

    PubMed

    Torrico, Damir Dennis; Sae-Eaw, Amporn; Sriwattana, Sujinda; Boeneke, Charles; Prinyawiwatkul, Witoon

    2015-06-01

    Little is known about how emulsion characteristics affect saltiness/bitterness perception. Sensory detection and recognition thresholds of NaCl, caffeine, and KCl in aqueous solution compared with oil-in-water emulsion systems were evaluated. For emulsions, NaCl, KCl, or caffeine were dissolved in water + emulsifier and mixed with canola oil (20% by weight). Two emulsions were prepared: emulsion 1 (viscosity = 257 cP) and emulsion 2 (viscosity = 59 cP). The forced-choice ascending concentration series method of limits (ASTM E-679-04) was used to determine detection and/or recognition thresholds at 25 °C. Group best estimate threshold (GBET) geometric means were expressed as g/100 mL. Comparing NaCl with KCl, there were no significant differences in detection GBET values for all systems (0.0197 - 0.0354). For saltiness recognition thresholds, KCl GBET values were higher compared with NaCl GBET (0.0822 - 0.1070 compared with 0.0471 - 0.0501). For NaCl and KCl, emulsion 1 and/or emulsion 2 did not significantly affect the saltiness recognition threshold compared with that of the aqueous solution. However, the bitterness recognition thresholds of caffeine and KCl in solution were significantly lower than in the emulsions (0.0242 - 0.0586 compared with 0.0754 - 0.1025). Gender generally had a marginal effect on threshold values. This study showed that, compared with the aqueous solutions, emulsions did not significantly affect the saltiness recognition threshold of NaCl and KCl, but exhibited bitterness-suppressing effects on KCl and/or caffeine.

  17. Biofilm Formation in Microscopic Double Emulsion Droplets

    NASA Astrophysics Data System (ADS)

    Chang, Connie; Weitz, David

    2012-02-01

    In natural, medical, and industrial settings, there exist surface-associated communities of bacteria known as biofilms. These highly structured films are composed of bacterial cells embedded within self-produced extracellular matrix, usually composed of exopolysaccharides, proteins, and nucleic acids; this matrix serves to protect the bacterial community from antibiotics and environmental stressors. Here, we form biofilms encapsulated within monodisperse, microscopically-sized double emulsion droplets using microfluidics. The bacteria self-organize at the inner liquid-liquid droplet interfaces, multiply, and differentiate into extracellular matrix-producing cells, forming manifold three-dimensional shell-within-a-shell structures of biofilms, templated upon the inner core of spherical liquid droplets. By using microfluidics to encapsulate bacterial cells, we have the ability to view individual cells multiplying in microscopically-sized droplets, which allows for high-throughput analysis in studying the genetic program leading to biofilm development, or cell signaling that induces differentiation.

  18. Mannan-stabilized oil-in-water beverage emulsions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The stabilizing effect of spruce galactoglucomannan (GGM) on a model beverage emulsion system was studied and compared to that of guar gum and locust bean gum galactomannans, konjac glucomannan, and corn arabinoxylan. In addition, enzymatic modification was applied on guar gum to examine the effect ...

  19. Acid preservation systems for food products

    SciTech Connect

    Tiberio, J. E.; Cirigiano, M. C.

    1984-10-16

    Fumaric acid is used in combination with critical amounts of acetic acid to preserve acid containing food products from microbiological spoilage in the absence of or at reduced levels of chemical preservative.

  20. ESR studies of semicontinuous emulsion polymerization

    SciTech Connect

    Lau, W.; Westmoreland, D.G.

    1993-12-31

    Electron spin resonance (ESR) is used in the detection and quantification of propagating radicals during a semicontinuous emulsion polymerization. The propagating radical concentration is crucial for the determination of kinetic parameters of the emulsion polymerization process. A flow reactor was built which involves a closed-loop flow system that circulates latex from the polymerization reactor through the ESR cavity for free-radical measurements and back to the reactor. With the continuous measurement of the radical concentrations during a polymerization of methyl methacrylate (MMA), {bar n} (average number of radicals per particle) and k{sub p} (propagating rate constant), are measured throughout the entire polymerization. For the polymerization of the MMA system studied, the authors observed a gradual increased in n and decrease in k{sub p} during the run, suggesting a diffusionally controlled process and that the polymerization is not occurring homogeneously throughout the polymer particles. In the glassy pMMA matrix, radicals can be {open_quotes}trapped{close_quotes} within a minimum volume and remain unterminated.

  1. Random close packing of polydisperse jammed emulsions

    NASA Astrophysics Data System (ADS)

    Brujic, Jasna

    2010-03-01

    Packing problems are everywhere, ranging from oil extraction through porous rocks to grain storage in silos and the compaction of pharmaceutical powders into tablets. At a given density, particulate systems pack into a mechanically stable and amorphous jammed state. Theoretical frameworks have proposed a connection between this jammed state and the glass transition, a thermodynamics of jamming, as well as geometric modeling of random packings. Nevertheless, a simple underlying mechanism for the random assembly of athermal particles, analogous to crystalline ordering, remains unknown. Here we use 3D measurements of polydisperse packings of emulsion droplets to build a simple statistical model in which the complexity of the global packing is distilled into a local stochastic process. From the perspective of a single particle the packing problem is reduced to the random formation of nearest neighbors, followed by a choice of contacts among them. The two key parameters in the model, the available space around a particle and the ratio of contacts to neighbors, are directly obtained from experiments. Remarkably, we demonstrate that this ``granocentric'' view captures the properties of the polydisperse emulsion packing, ranging from the microscopic distributions of nearest neighbors and contacts to local density fluctuations and all the way to the global packing density. Further applications to monodisperse and bidisperse systems quantitatively agree with previously measured trends in global density. This model therefore reveals a general principle of organization for random packing and lays the foundations for a theory of jammed matter.

  2. Emulsion stability measurements by single electrode capacitance probe (SeCaP) technology

    NASA Astrophysics Data System (ADS)

    Schüller, R. B.; Løkra, S.; Salas-Bringas, C.; Egelandsdal, B.; Engebretsen, B.

    2008-08-01

    This paper describes a new and novel method for the determination of the stability of emulsions. The method is based on the single electrode capacitance technology (SeCaP). A measuring system consisting of eight individual measuring cells, each with a volume of approximately 10 ml, is described in detail. The system has been tested on an emulsion system based on whey proteins (WPC80), oil and water. Xanthan was added to modify the emulsion stability. The results show that the new measuring system is able to quantify the stability of the emulsion in terms of a differential variable. The whole separation process is observed much faster in the SeCaP system than in a conventional separation column. The complete separation process observed visually over 30 h is seen in less than 1.4 h in the SeCaP system.

  3. Emulsion-cryogelation technique for fabricating a versatile toolbox of hierarchical polymeric monolith and its application in chromatography.

    PubMed

    Li, Yaping; Qi, Li; Li, Nan; Ma, Huimin

    2016-05-15

    A novel poly (glycidyl methacrylate-co-ethylene dimethacrylate) monolith has been fabricated via the environmental friendly cryogelation-emulsion technique. The polymerization process is assisted by self-assembly of typical tri-block copolymer Pluronic F127 at sub-zero temperature using ice crystal as template, which can avoid consumption of organic porogenic solvents and thermal unstability of emulsion system. The developed monolith possesses hierarchical networks, which is confirmed by nitrogen adsorption measurement, mercury intrusion porosimetry, scanning electron microscopy and permeability testing. Further, the effect of the amounts of Pluronic F127 on the microstructure has been investigated. Moreover, the prepared polymer monolith undergoes acidic hydrolysis of epoxy groups into hydroxyl groups on the surface and its liquid chromatographic performance is explored by separating model analytes. The results indicate that the unique porous polymer monolith with hierarchical networks could be prepared via an organic porogen-free approach and used for analysis of polar and nonpolar molecules, extending the application of cryogelation-emulsion technique and methacrylate-based monolith.

  4. Analysis of emulsion stability in acrylic dispersions

    NASA Astrophysics Data System (ADS)

    Ahuja, Suresh

    2012-02-01

    Emulsions either micro or nano permit transport or solubilization of hydrophobic substances within a water-based phase. Different methods have been introduced at laboratory and industrial scales: mechanical stirring, high-pressure homogenization, or ultrasonics. In digital imaging, toners may be formed by aggregating a colorant with a latex polymer formed by batch or semi-continuous emulsion polymerization. Latex emulsions are prepared by making a monomer emulsion with monomer like Beta-carboxy ethyl acrylate (β-CEA) and stirring at high speed with an anionic surfactant like branched sodium dodecyl benzene sulfonates , aqueous solution until an emulsion is formed. Initiator for emulsion polymerization is 2-2'- azobis isobutyramide dehydrate with chain transfer agent are used to make the latex. If the latex emulsion is unstable, the resulting latexes produce a toner with larger particle size, broader particle size distribution with relatively higher latex sedimentation, and broader molecular weight distribution. Oswald ripening and coalescence cause droplet size to increase and can result in destabilization of emulsions. Shear thinning and elasticity of emulsions are applied to determine emulsion stability.

  5. Interfacial composition and stability of emulsions made with mixtures of commercial sodium caseinate and whey protein concentrate.

    PubMed

    Ye, Aiqian

    2008-10-15

    The interfacial composition and the stability of oil-in-water emulsion droplets (30% soya oil, pH 7.0) made with mixtures of sodium caseinate and whey protein concentrate (WPC) (1:1 by protein weight) at various total protein concentrations were examined. The average volume-surface diameter (d32) and the total surface protein concentration of emulsion droplets were similar to those of emulsions made with both sodium caseinate alone and WPC alone. Whey proteins were adsorbed in preference to caseins at low protein concentrations (<3%), whereas caseins were adsorbed in preference to whey proteins at high protein concentrations. The creaming stability of the emulsions decreased markedly as the total protein concentration of the system was increased above 2% (sodium caseinate >1%). This was attributed to depletion flocculation caused by the sodium caseinate in these emulsions. Whey proteins did not retard this instability in the emulsions made with mixtures of sodium caseinate and WPC.

  6. Optimum phase-behavior formulation of surfactant/oil/water systems for the determination of chromium in heavy crude oil and in bitumen-in-water emulsion.

    PubMed

    Burguera, José L; Avila-Gómez, Rita M; Burguera, Marcela; Antón de Salager, Raquel; Salager, Jean-Louis; Bracho, Carlos L; Burguera-Pascu, Margarita; Burguera-Pascu, Constantin; Brunetto, Rosario; Gallignani, Máximo; Petit de Peña, Yaneita

    2003-11-04

    An "oil in water" formulation was optimized to determine chromium in heavy crude oil (HCO) and bitumen-in-water emulsion (Orimulsion-400(R)) samples by transversally heated electrothermal atomic absorption spectrometry (TH-ET AAS) using Zeeman effect background correction. The optimum proportion of the oil-water mixture ratio was 7:3 v/v (70 ml of oil as the internal phase) with a non-ionic surfactant concentration (Intan-100) in the emulsion of 0.2% w/w. Chromium was determined in different crude oil samples after dilution of the emulsions 1:9 v/v with a 0.2% w/w solution of surfactant in order to further reduce the viscosity from 100 to 1.6 cP and at the same time to bring the concentration of chromium within the working range of the ET AAS technique. The calibration graph was linear from 1.7 to 100 mug Cr l(-1). The sensitivity was of 0.0069 s l mug(-1), the characteristic mass (m(o)) was of 5.7 pg per 0.0044 s and the detection limit (3sigma) was of 0.52 mug l(-1). The relative standard deviation of the method, evaluated by replicate analyses of three crude oil samples varied in all cases between 1.5 and 2.6%. Recovery studies were performed on four Venezuelan crude oils, and the average chromium recovery values varied between 95.9-104.8, 90.6-107.6, 95.6-104.0 and 98.8-103.9% for the Cerro Negro, Crudo Hamaca and Boscán crude oils and for the Orimulsión(R)-400, respectively. The results obtained in this work for the Cerro Negro, Crudo Hamaca and Boscán crude oils and for the Orimulsión(R)-400 following the proposed procedure were of 0.448+/-0.008, 0.338+/-0.004 0.524+/-0.021 and 0.174+/-0.008 mg Cr l(-1), respectively, which were in good agreement with the values obtained by a tedious recommended standard procedure (respectively: 0.470+/-0.05, 0.335+/-0.080, 0.570+/-0.021 and 0.173+/-0.009 mg Cr l(-1)).

  7. Preparation and characterization of narrow sized (o/w) magnetic emulsion

    NASA Astrophysics Data System (ADS)

    Montagne, F.; Mondain-Monval, O.; Pichot, C.; Mozzanega, H.; Elaı̈ssari, A.

    2002-09-01

    The preparation of well-defined (o/w) magnetic emulsions from an organic ferrofluid is reported. The ferrofluid synthesis is first described and a complete characterization is achieved by using numerous techniques. The ferrofluid is found to be composed of superparamagnetic maghemite nanoparticles, with a diameter below 10 nm, stabilized in octane by a surrounding oleic acid layer. This magnetic fluid is then emulsified in aqueous media in order to obtain stable ferrofluid droplets. The use of a couette mixer and a size sorting step under magnetic field allowed to produce magnetic emulsion with a narrow size distribution. Morphology and chemical composition of the magnetic emulsion are investigated. Magnetic properties of both ferrofluid and magnetic emulsion are also compared and discussed. In particular, it is showed that the superparamagnetic behavior is still observed after the emulsification process.

  8. Prompt inhibition of fMLP-induced Ca2+ mobilization by parenteral lipid emulsions in human neutrophils.

    PubMed

    Wanten, Geert; Rops, Angelique; van Emst-De Vries, Sjenet E; Naber, Ton; Willems, Peter H G M

    2002-04-01

    It remains unclear whether modulation of immune system functions by lipids contributes to the increased infection rate observed in patients treated with parenteral nutrition. We therefore evaluated the effects of lipid emulsions derived from fish oil [very long chain triglycerides (VLCT)], olive oil [long-chain triglycerides- mono-unsaturated fatty acid (LCT-MUFA)], soya oil [long-chain triglycerides (LCT)], or a physical mixture of coconut and soya oil [mixed long- and medium-chain triglycerides (LCT-MCT)] on neutrophil activation. N-formyl-methionyl-leucyl-phenylalanine (fMLP) evoked an immediate increase of the cytosolic Ca2+ concentration ([Ca2+](i,av)) in a suspension of neutrophils. When added 3 min before fMLP, however, all four lipid emulsions reduced the hormone-induced increase in [Ca2+](i,av) with the same efficacy but with different potency. Half-maximal inhibition was reached at emulsion concentrations of 0.24 mM VLCT, 0.32 mM LCT-MCT, 0.52 mM LCT, and 0.82 mM LCT-MUFA. Similarly to the lipids, the protein kinase C (PKC) activator PMA markedly reduced the fMLP-induced increase in [Ca2+](i,av). PMA inhibition was abolished by the PKC inhibitor staurosporine. In contrast, however, this drug did not interfere with the inhibitory lipid effect, indicating that the lipids act primarily in a PKC-independent manner. In summary, this study shows that nutritional lipids can evoke a prompt and significant attenuation of hormone-induced neutrophil stimulation and that the emulsions based on fish oil and a mixture of coconut oil and soya oil are among the most potent ones in this respect.

  9. Krill Oil-In-Water Emulsion Protects against Lipopolysaccharide-Induced Proinflammatory Activation of Macrophages In Vitro

    PubMed Central

    Bonaterra, Gabriel A.; Driscoll, David; Schwarzbach, Hans; Kinscherf, Ralf

    2017-01-01

    Background: Parenteral nutrition is often a mandatory therapeutic strategy for cases of septicemia. Likewise, therapeutic application of anti-oxidants, anti-inflammatory therapy, and endotoxin lowering, by removal or inactivation, might be beneficial to ameliorate the systemic inflammatory response during the acute phases of critical illness. Concerning anti-inflammatory properties in this setting, omega-3 fatty acids of marine origin have been frequently described. This study investigated the anti-inflammatory and LPS-inactivating properties of krill oil (KO)-in-water emulsion in human macrophages in vitro. Materials and Methods: Differentiated THP-1 macrophages were activated using specific ultrapure-LPS that binds only on the toll-like receptor 4 (TLR4) in order to determine the inhibitory properties of the KO emulsion on the LPS-binding capacity, and the subsequent release of TNF-α. Results: KO emulsion inhibited the macrophage binding of LPS to the TLR4 by 50% (at 12.5 µg/mL) and 75% (at 25 µg/mL), whereas, at 50 µg/mL, completely abolished the LPS binding. Moreover, KO (12.5 µg/mL, 25 µg/mL, or 50 µg/mL) also inhibited (30%, 40%, or 75%, respectively) the TNF-α release after activation with 0.01 µg/mL LPS in comparison with LPS treatment alone. Conclusion: KO emulsion influences the LPS-induced pro-inflammatory activation of macrophages, possibly due to inactivation of the LPS binding capacity. PMID:28294970

  10. Antioxidative effect of lipophilized caffeic acid in fish oil enriched mayonnaise and milk.

    PubMed

    Alemán, Mercedes; Bou, Ricard; Guardiola, Francesc; Durand, Erwann; Villeneuve, Pierre; Jacobsen, Charlotte; Sørensen, Ann-Dorit Moltke

    2015-01-15

    The antioxidative effect of lipophilized caffeic acid was assessed in two different fish oil enriched food products: mayonnaise and milk. In both emulsion systems, caffeic acid esterified with fatty alcohols of different chain lengths (C1-C20) were better antioxidants than the original phenolic compound. The optimal chain length with respect to protection against oxidation was, however, different for the two food systems. Fish oil enriched mayonnaise with caffeates of medium alkyl chain length (butyl, octyl and dodecyl) added resulted in a better oxidative stability than caffeates with shorter (methyl) or longer (octadecyl) alkyl chains. Whereas in fish oil enriched milk emulsions the most effective caffeates were those with shorter alkyl chains (methyl and butyl) rather than the ones with medium and long chains (octyl, dodecyl, hexadecyl and eicosyl). These results demonstrate that there might be an optimum alkyl chain length for each phenolipid in each type of emulsion systems.

  11. Stabilization mechanisms of oil-in-water emulsions by Saccharomyces cerevisiae.

    PubMed

    Moreira, Thais Caldas Paiva; da Silva, Vanessa Martins; Gombert, Andreas Karoly; da Cunha, Rosiane Lopes

    2016-07-01

    A multiphase system is commonly formed during the oil production by microbial route, which can lead to stable emulsions hindering product recovery. Thus, this study aimed to investigate the mechanisms of emulsion stabilization by the yeast Saccharomyces cerevisiae in order to contribute with processes development of oil production by fermentation. A model system using hexadecane as oil phase and yeast suspension as aqueous phase was used to prepare O/W emulsions. The yeast was subjected to different treatments as inactivation (autoclaving) and washing before to be resuspended in water. The washing water (water from the first washing) and suspension of commercial yeast (active) were also used as aqueous phase. After 24h of preparation, the emulsions separated into three phases: top (cream), intermediate, and bottom phase. The top or cream phase was a concentrated emulsion that kept stable during seven days, except for those prepared from washed yeast that were stable only for a short period of time. Emulsions prepared with washed yeast showed higher cell adhesion to the droplets interface, which implied in a higher amount of yeast into the cream phase in comparison to other formulations. Therefore, yeast cells adhesion plays a role on emulsion stability, but the greater contribution was provided by cell material dispersed into the aqueous phase, regardless of cell viability.

  12. Impact of acoustic cavitation on food emulsions.

    PubMed

    Krasulya, Olga; Bogush, Vladimir; Trishina, Victoria; Potoroko, Irina; Khmelev, Sergey; Sivashanmugam, Palani; Anandan, Sambandam

    2016-05-01

    The work explores the experimental and theoretical aspects of emulsification capability of ultrasound to deliver stable emulsions of sunflower oil in water and meat sausages. In order to determine optimal parameters for direct ultrasonic emulsification of food emulsions, a model was developed based on the stability of emulsion droplets in acoustic cavitation field. The study is further extended to investigate the ultrasound induced changes to the inherent properties of raw materials under the experimental conditions of sono-emulsification.

  13. Recent Studies of Pickering Emulsions: Particles Make the Difference.

    PubMed

    Wu, Jie; Ma, Guang-Hui

    2016-09-01

    In recent years, emulsions stabilized by micro- or nanoparticles (known as Pickering emulsions) have attracted much attention. Micro- or nanoparticles, as the main components of the emulsion, play a key role in the preparation and application of Pickering emulsions. The existence of particles at the interface between the oil and aqueous phases affects not only the preparation, but also the properties of Pickering emulsions, affording superior stability, low toxicity, and stimuli-responsiveness compared to classical emulsions stabilized by surfactants. These advantages of Pickering emulsions make them attractive, especially in biomedicine. In this review, the effects of the characteristics of micro- and nanoparticles on the preparation and properties of Pickering emulsions are introduced. In particular, the preparation methods of Pickering emulsions, especially uniform-sized emulsions, are listed. Uniform Pickering emulsions are convenient for both mechanistic research and applications. Furthermore, some biomedical applications of Pickering emulsions are discussed and the problems hindering their clinical application are identified.

  14. Structures similar to lipid emulsions and liposomes. Dipalmitoylphosphatidylcholine, cholesterol, Tween 20-Span 20 or Tween 80-Span 80 in aqueous media.

    PubMed

    Juárez-Osornio, Carlos; Gracia-Fadrique, Jesús

    2017-06-01

    In the present work, we show that we obtained nanometric structures made of water, 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC), cholesterol (Chol), and a mixture of ethoxylated and non-ethoxylated sorbitan fatty acid esters (Tween 20, Span 20, Tween 80, and Span 80) by mixing all of them near the cloud point temperature (cp) of the ethoxylated surfactant. The influence that the constituents had on the size of the particle was determined by a pseudo-ternary phase diagram of water/Tween-Span/DPPC-Chol; the colloidal particles obtained were studied by differential scanning calorimetry, confocal fluorescence microscopy, scanning electron microscopy, and atomic force microscopy. These studies were made for all the systems with at least 23 d of colloidal stability. The most stable system was obtained with the Tween 80-Span 80 pair, behaving as a typical suspension for 48 d; this system was made of water, Tween 80-Span 80 (80:20), DPPC-Chol (95:5) in a corresponding molar ratio of 48:37:100:10. The colloidal particles obtained were a kind of emulsion and liposome structures. The second stable system was obtained with the same mixture, but in a molar ratio of 8:6:9:0, its structure was also a kind of emulsion particles. In both systems and in other less stable ones, the "emulsion particle" was completely new, it structurally corresponds to a nucleus of mixed micelles surrounded by at least one bilayer of DPPC.

  15. Adelphi-Goddard emulsified fuel project. [using water/oil emulsions

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Thermal efficiency and particle emissions were studied using water/oil emulsions. These studies were done using number 2 and number 6 fuel oil. The number 6 oil had a sulfur content greater than one percent and experiments were conducted to remove the sulfur dioxide from the stack gases. Test findings include: (1) emulsion effected a reduction in soot at a low excess air levels; (2) a steam atomizing system will produce a water/oil emulsion. The fuel in the study was emulsified in the steam atomization process, hence, pre-emulsification did not yield a dramatic reduction in soot or an increase in thermal efficiency.

  16. Hydroxybenzoic acid isomers and the cardiovascular system

    PubMed Central

    2014-01-01

    Today we are beginning to understand how phytochemicals can influence metabolism, cellular signaling and gene expression. The hydroxybenzoic acids are related to salicylic acid and salicin, the first compounds isolated that have a pharmacological activity. In this review we examine how a number of hydroxyphenolics have the potential to ameliorate cardiovascular problems related to aging such as hypertension, atherosclerosis and dyslipidemia. The compounds focused upon include 2,3-dihydroxybenzoic acid (Pyrocatechuic acid), 2,5-dihydroxybenzoic acid (Gentisic acid), 3,4-dihydroxybenzoic acid (Protocatechuic acid), 3,5-dihydroxybenzoic acid (α-Resorcylic acid) and 3-monohydroxybenzoic acid. The latter two compounds activate the hydroxycarboxylic acid receptors with a consequence there is a reduction in adipocyte lipolysis with potential improvements of blood lipid profiles. Several of the other compounds can activate the Nrf2 signaling pathway that increases the expression of antioxidant enzymes, thereby decreasing oxidative stress and associated problems such as endothelial dysfunction that leads to hypertension as well as decreasing generalized inflammation that can lead to problems such as atherosclerosis. It has been known for many years that increased consumption of fruits and vegetables promotes health. We are beginning to understand how specific phytochemicals are responsible for such therapeutic effects. Hippocrates’ dictum of ‘Let food be your medicine and medicine your food’ can now be experimentally tested and the results of such experiments will enhance the ability of nutritionists to devise specific health-promoting diets. PMID:24943896

  17. Transdermal delivery of forskolin from emulsions differing in droplet size.

    PubMed

    Sikora, Elżbieta; Llinas, Meritxell; Garcia-Celma, Maria Jose; Escribano, Elvira; Solans, Conxita

    2015-02-01

    The skin permeation of forskolin, a diterpene isolated from Coleus forsholii, was studied using oil in water (O/W) emulsions as delivery formulations and also an oil solution for comparative purposes. Two forskolin-loaded emulsions of water/Brij 72:Symperonic A7/Miglyol 812:Isohexadecane, at 0.075 wt% forskolin concentration were prepared with the same composition and only differing in droplet size (0.38 μm and 10 μm). The emulsions showed high kinetic stability at 25 °C. In vitro study of forskolin penetration through human skin was carried out using the MicroettePlus(®) system. The concentration of the active in the receptor solution (i.e. ethanol/phosphate buffer 40/60, v/v) was analyzed by high performance liquid chromatography with UV detection. The obtained results showed that forskolin permeation from the emulsions and the oil solution, through human skin, was very high (up to 72.10%), and no effect of droplet size was observed.

  18. Improvement of graft function and animal survival by fat emulsion in liver transplant rats.

    PubMed

    Ma, Zheng-Wei; Liu, Li-Dong; Li, Kun; Zhang, Yu-Jun; Dong, Jia-Hong

    2007-01-15

    Nutritional supports are required for liver transplant patients. However, no systematical assessment has been made of the optimal composition of energy yielding substrates in these patients. This study is to evaluate whether mixed energy system consisting of carbohydrate and lipid emulsions is more advantageous over single energy source of glucose for nutritional support in liver transplant recipients and whether structured lipid emulsion (STG) is superior to medium-chain triglyceride/long-chain triglycerides (MCT/LCT) and long-chain triglycerides (LCT) using a total parenteral nutrition model. Liver transplant rats were randomly divided to four groups according to the energy source, i.e. glucose (GLU), MCT/LCT, STG and LCT groups. Sham operated rats served as control. Hepatic function and lipid profile were determined to investigate the roles of lipid emulsion in hepatic function and lipid metabolism. Morphological changes of liver were observed, and nitrogen balance was determined. The results showed that infusion of lipid emulsion was well tolerated. The 1-week survival rate in the lipid emulsion groups was significantly higher than in the GLU group (100% versus 50%, P<0.05); compared with the GLU group, hepatic function recovered quickly and returned to normal level, and morphological alterations were less severer in the lipid emulsion groups, especially in the STG group; the lipid emulsions groups had normal serum TG and TC levels, especially STG and MCT/LCT groups; the lipid emulsions groups achieved a positive nitrogen balance on day 7 compared with the GLU group, and the STG group had the highest nitrogen balance. In conclusion, lipid emulsion is beneficial in improving hepatic function and the recipients' survival and does not influence the lipid metabolism. Mixed energy system consisting of carbohydrate and lipid is more advantageous over single energy source of glucose after liver transplantation, and STG is superior to MCT/LCT and LCT.

  19. Combined Effect of Kimchi Powder and Onion Peel Extract on Quality Characteristics of Emulsion Sausages Prepared with Irradiated Pork

    PubMed Central

    Choi, Yun-Sang; Lee, Ju-Woon; Lee, Si-Kyung

    2015-01-01

    This study was conducted to investigate the effects of kimchi powder and onion peel extract on the quality characteristics of emulsion sausage manufactured with irradiated pork. The emulsion sausages were formulated with 2% kimchi powder and/or 0.05% onion peel extract. The changes in pH value of all treatments were similar, depending on storage periods. The addition of kimchi powder increased the redness and yellowness of the emulsion sausage. The addition of onion peel extract decreased the thiobarbituric acid reactive substances value of the emulsion sausages prepared with irradiated pork. The volatile basic nitrogen value of the emulsion sausage prepared with kimchi powder was the highest, whereas that of the emulsion sausage prepared with onion peel extract was the lowest. The treatment without kimchi powder or onion peel extract and the treatments prepared with onion peel extract showed lower microbial populations than the other treatment. Sensory evaluations indicated that a higher acceptability was attained when kimchi powder was added to the emulsion sausages manufactured with irradiated pork. In conclusion, our results suggest that combined use of kimchi powder and onion peel extract could improve quality characteristics and shelf stability of the emulsion sausage formulated with irradiated pork during chilled storage. PMID:26761840

  20. Effects of salts on oxidative stability of lipids in Tween-20 stabilized oil-in-water emulsions.

    PubMed

    Cui, Leqi; Cho, Hyung Taek; McClements, D Julian; Decker, Eric A; Park, Yeonhwa

    2016-04-15

    Lipid oxidation in oil-in-water (O/W) emulsions is an important factor determining the shelf life of food products. Salts are often present in many types of emulsion based food products. However, there is limited information on influence of salts on lipid oxidation in O/W emulsions. Thus, the purpose of this study was to examine the effects of sodium and potassium chloride on lipid oxidation in O/W emulsions. Tween 20 stabilized corn O/W emulsions at pH 7.0 were prepared with different concentrations of sodium chloride with or without the metal chelators. NaCl did not cause any changes in emulsion droplet size. NaCl dose-dependently promoted lipid oxidation as measured by the lipid oxidation product, hexanal. Both deferoxamine (DFO) and ethylenediaminetetraacetic acid (EDTA) reduced lipid oxidation in emulsions with NaCl, with EDTA being more effective. Potassium chloride showed similar impact on lipid oxidation as sodium chloride. These results suggest that salts are able to promote lipid oxidation in emulsions and this effect can be controlled by metal chelators.

  1. Rheology and stability of acidified food emulsions treated with high pressure.

    PubMed

    Arora, Akshay; Chism, Grady W; Shellhammer, Thomas H

    2003-04-23

    The stability and rheology of acidified model oil-in-water emulsions (pH 3.6 +/- 0.1) were evaluated before and after high-pressure treatments. Varying concentrations of canola oil (0-50% w/w), whey protein isolate, polysorbate 60, soy lecithin (0.1-1.5% w/w each), and xanthan (0.0-0.2% w/w) were chosen. Exposure to high pressures (up to 800 MPa for 5 min at 30 degrees C) did not significantly affect the equivalent surface mean diameter D[3,2], flow behavior, and viscoelasticity of the whey protein isolate and polysorbate 60-stabilized emulsions. Pressure treatments had negligible effects on emulsion stability in these systems, except when xanthan (0.2% w/w) was present in which pressure improved the stability of polysorbate 60-stabilized emulsions. Soy lecithin-stabilized emulsions had larger mean particles sizes and lower emulsion volume indices than the others, indicating potential instability, and application of pressure further destabilized these emulsions.

  2. The Influence of Maltodextrin on the Physicochemical Properties and Stabilization of Beta-carotene Emulsions.

    PubMed

    Zhang, Jianpan; Zhang, Xiaoxu; Wang, Xinyi; Huang, Ying; Yang, Beibei; Pan, Xin; Wu, Chuanbin

    2016-06-27

    Beta-carotene is important for fortification of nutritional products while its application is limited by instability. The influence of maltodextrin (MDX) on physicochemical properties and stability of beta-carotene emulsions stabilized by sodium caseinate (SC) was investigated. The emulsions were characterized by dynamic light scattering (DLS), laser diffraction (LD), transmission electron microscopy (TEM), rheometer, and turbiscan lab expert. The effects of pH, ionic strength, and freeze-thaw on stability of emulsions were observed. The emulsions could tolerate up to 2 mol/L NaCl or 10 mmol/L CaCl2 and showed Newtonian behavior. The droplet diameter, polydispersity index, and zeta-potential did not change obviously after 3 months storage at 4°C in dark conditions. The emulsions with MDX showed excellent freeze-thaw stability and gave favorite protection for beta-carotene. The retention ratio of beta-carotene in the emulsions with MDX was above 92.1% after 3 months storage while that in the one without MDX was only 62.7%. The study may provide a promising strategy to improve stability of sensitive nutraceuticals without adding synthetic antioxidants. The findings obtained could provide fundamental basis for rational design of emulsion delivery systems when freeze-thawing is required during manufacturing process or storage period.

  3. Impact of Protein Gel Porosity on the Digestion of Lipid Emulsions.

    PubMed

    Sarkar, Anwesha; Juan, Jean-Marc; Kolodziejczyk, Eric; Acquistapace, Simone; Donato-Capel, Laurence; Wooster, Tim J

    2015-10-14

    The present study sought to understand how the microstructure of protein gels impacts lipolysis of gelled emulsions. The selected system consisted of an oil-in-water (o/w) emulsion embedded within gelatin gels. The gelatin-gelled emulsions consisted of a discontinuous network of aggregated emulsion droplets (mesoscale), dispersed within a continuous network of gelatin (microscale). The viscoelastic properties of the gelled emulsions were dominated by the rheological behavior of the gelatin, suggesting a gelatin continuous microstructure rather than a bicontinuous gel. A direct relationship between the speed of fat digestion and gel average mesh size was found, indicating that the digestion of fat within gelatin-gelled emulsions is controlled by the ability of the gel's microstructure to slow lipase diffusion to the interface of fat droplets. Digestion of fat was facilitated by gradual breakdown of the gelatin network, which mainly occurred via surface erosion catalyzed by proteases. Overall, this work has demonstrated that the lipolysis kinetics of gelled emulsions is driven by the microstructure of protein gels; this knowledge is key for the future development of microstructures to control fat digestion and/or the delivery of nutrients to different parts of the gastrointestinal tract.

  4. Characterization of starch Pickering emulsions for potential applications in topical formulations.

    PubMed

    Marku, Diana; Wahlgren, Marie; Rayner, Marilyn; Sjöö, Malin; Timgren, Anna

    2012-05-30

    The aim of this work has been to characterize starch based Pickering emulsions as a first step to evaluate their possible use as vehicles for topical drug delivery. A minor phase study of emulsions with high oil content has been performed. Emulsion stability against coalescence over eight weeks and after mild centrifugation treatment has been studied. The particle size, rheological properties and in vitro skin penetration of emulsions containing three different oils (Miglyol, paraffin and sheanut oil) was investigated. It was shown that it is possible to produce oil in water starched stabilised Pickering emulsions with oil content as high as 56%. Furthermore, this emulsions show good stability during storage over eight weeks and towards mild centrifugation. The particle size of the systems are only dependent on the ratio between oil and starch and for liquid oils the type of oil do not affect the particle size. The type of oil also affects the cosmetic and rheological properties of the creams but did not affect the transdermal diffusion in in vitro tests. However, it seems as if the Pickering emulsions affected the transport over the skin, as the flux was twice that of what has been previously reported for solutions.

  5. Investigating droplet internal flow in concentrated emulsion when flowing in microchannel using micro-PIV

    NASA Astrophysics Data System (ADS)

    Leong, Chia Min; Gai, Ya; Tang, Sindy K. Y.

    2016-11-01

    Droplet microfluidics has enabled a wide variety of high throughput applications through the use of monodisperse droplets. Previous fluid studies of droplet microfluidics have focused on single drops or emulsions at low volume fractions. The study of concentrated emulsions at high volume fractions is important for increasing the throughput, but the fluid dynamics of such emulsions in confined channels is not well understood. Here we describe two-dimensional, mid-height measurements of the flow inside individual drops within a concentrated emulsion using micro-PIV. The emulsion has 85% volume fraction and flows as a monolayer in a straight microfluidic channel. The effects of confinement and viscosity ratio on the internal flow patterns inside the drops were studied. The results show rotational structures inside the drops always exist, and are independent of viscosity ratio for the conditions tested. The structures depend on droplet mobility which in turn, depends on the confinement of the emulsion and the location of the drops in the channel. To our best knowledge, no work has probed the flow field inside droplets of concentrated emulsions at high volume fractions in confined channels. Current work is in progress to measure the three-dimensional flow field in such system.

  6. Aqueous Tape Casting of Alumina using an Emulsion of Urethane Polymer

    NASA Astrophysics Data System (ADS)

    Takaishi, T.; Inada, H.; Sato, M.; Sano, S.; Kawakami, S.

    2011-05-01

    From the viewpoint of solving environmental problems, changeover from organic solvent-based system to water-based system in tape casting process has been required. The effects of organic additives on the rheological properties of water-based alumina slurries were investigated. The aqueous slurries were prepared from low-soda alumina powder, deionized water, ammonium salt of polycarboxylic acid type dispersant, emulsion type urethane polymer binder and defoamer. By means of the zeta potential measurement, the optimum content of added dispersant was estimated. Furthermore, precipitation test, viscosity measurement and so on were performed. From these measurements, it was decided that optimum amounts of dispersant and binder were 0.8 mass% and 12 mass%, respectively. Well-dispersed and high solid content slurry gave good quality green sheets, and high density sintered bodies were obtained.

  7. Determination of Mo and V in multiphase gasoline emulsions by electrothermal atomic absorption spectrometry

    NASA Astrophysics Data System (ADS)

    Santana Sodré dos Santos, Denilson; Paixão Teixeira, Alete; das Graças Andrade Korn, Maria; Sena Gomes Teixeira, Leonardo

    2006-05-01

    This paper proposes an alternative analytical method using electrothermal atomic absorption spectrometry to determine Mo and V in multiphase gasoline emulsions. Samples were prepared by mixing gasoline with a nitric acid solution (0.1% v/v) and two cationic surfactants. The mixture was sonicated, resulting in an emulsive system. Calibration was done by using the aforementioned solutions with added analyte. The detection limits (3 σ) of Mo and V were 0.9 μg l - 1 and 4.7 μg l - 1 , respectively. The accuracy and precision of the proposed method were evaluated by the analysis of samples spiked with metallo-organic standard and the relative standard deviation obtained ranged from 1.2% to 4.4% in samples spiked with 2 μg l - 1 of each metal. The recovery rates varied from 91.2% to 101.6%. The proposed method was applied to determine Mo and V in samples of gasoline from different gas stations.

  8. 21 CFR 862.1509 - Methylmalonic acid (nonquantitative) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Methylmalonic acid (nonquantitative) test system. 862.1509 Section 862.1509 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Test Systems § 862.1509 Methylmalonic acid (nonquantitative) test system. (a) Identification....

  9. NEWS: Nuclear Emulsions for WIMP Search

    NASA Astrophysics Data System (ADS)

    Di Marco, Natalia; NEWS Collaboration

    2016-05-01

    In the field of direct Dark Matter search a different and promising approach is the directionality: the observation of the incoming apparent direction of WIMPs would in fact provide a new and unambiguous signature. The NEWS project is a very innovative approach for a high sensitivity experiment aiming at the directional detection of WIMPs: the detector is based on a novel emulsion technology called NIT (Nano Imaging Trackers) acting both as target and tracking device. In this paper we illustrate the features of a NIT-based detector and the newly developed read-out systems allowing to reach a spatial resolution of the order of 10 nm. We present the background studies and the experimental design. Finally we report about the time schedule of the experiment and the expected sensitivity for DM searches.

  10. Metallic nanoshells on porphyrin-stabilized emulsions

    DOEpatents

    Wang, Haorong; Song, Yujiang; Shelnutt, John A; Medforth, Craig J

    2013-10-29

    Metal nanostructures formed by photocatalytic interfacial synthesis using a porphyrin-stabilized emulsion template and the method for making the nanostructures. Catalyst-seeded emulsion droplets are employed as templates for hollow-nanoshell growth. The hollow metal nanospheres may be formed with or without inclusions of other materials.

  11. Kinetics of crosslinking in emulsion polymerization

    SciTech Connect

    Ghielmi, A.; Fiorentino, S.; Morbidelli, M.

    1996-12-31

    A mathematical model for evaluating the chain length distribution of nonlinear polymers produced in emulsions is presented. The heterogeneous emulsion polymerization process is described. The aim of the analysis is the distribution of active polymer chains and pairs of chains with a given growth time in latex particles in state.

  12. Flows of Wet Foamsand Concentrated Emulsions

    NASA Technical Reports Server (NTRS)

    Nemer, Martin B.

    2005-01-01

    The aim of this project was is to advance a microstructural understanding of foam and emulsion flows. The dynamics of individual surfactant-covered drops and well as the collective behavior of dilute and concentrated was explored using numerical simulations. The long-range goal of this work is the formulation of reliable microphysically-based statistical models of emulsion flows.

  13. Altering Emulsion Stability with Heterogeneous Surface Wettability

    PubMed Central

    Meng, Qiang; Zhang, Yali; Li, Jiang; Lammertink, Rob G. H.; Chen, Haosheng; Tsai, Peichun Amy

    2016-01-01

    Emulsions–liquid droplets dispersed in another immiscible liquid–are widely used in a broad spectrum of applications, including food, personal care, agrochemical, and pharmaceutical products. Emulsions are also commonly present in natural crude oil, hampering the production and quality of petroleum fuels. The stability of emulsions plays a crucial role in their applications, but controlling the stability without external driving forces has been proven to be difficult. Here we show how heterogeneous surface wettability can alter the stability and dynamics of oil-in-water emulsions, generated by a co-flow microfluidic device. We designed a useful methodology that can modify a micro-capillary of desired heterogeneous wettability (e.g., alternating hydrophilic and hydrophobic regions) without changing the hydraulic diameter. We subsequently investigated the effects of flow rates and heterogeneous wettability on the emulsion morphology and motion. The experimental data revealed a universal critical timescale of advective emulsions, above which the microfluidic emulsions remain stable and intact, whereas below they become adhesive or inverse. A simple theoretical model based on a force balance can be used to explain this critical transition of emulsion dynamics, depending on the droplet size and the Capillary number–the ratio of viscous to surface effects. These results give insight into how to control the stability and dynamics of emulsions in microfluidics with flow velocity and different wettability. PMID:27256703

  14. Altering Emulsion Stability with Heterogeneous Surface Wettability

    NASA Astrophysics Data System (ADS)

    Meng, Qiang; Zhang, Yali; Li, Jiang; Lammertink, Rob G. H.; Chen, Haosheng; Tsai, Peichun Amy

    2016-06-01

    Emulsions–liquid droplets dispersed in another immiscible liquid–are widely used in a broad spectrum of applications, including food, personal care, agrochemical, and pharmaceutical products. Emulsions are also commonly present in natural crude oil, hampering the production and quality of petroleum fuels. The stability of emulsions plays a crucial role in their applications, but controlling the stability without external driving forces has been proven to be difficult. Here we show how heterogeneous surface wettability can alter the stability and dynamics of oil-in-water emulsions, generated by a co-flow microfluidic device. We designed a useful methodology that can modify a micro-capillary of desired heterogeneous wettability (e.g., alternating hydrophilic and hydrophobic regions) without changing the hydraulic diameter. We subsequently investigated the effects of flow rates and heterogeneous wettability on the emulsion morphology and motion. The experimental data revealed a universal critical timescale of advective emulsions, above which the microfluidic emulsions remain stable and intact, whereas below they become adhesive or inverse. A simple theoretical model based on a force balance can be used to explain this critical transition of emulsion dynamics, depending on the droplet size and the Capillary number–the ratio of viscous to surface effects. These results give insight into how to control the stability and dynamics of emulsions in microfluidics with flow velocity and different wettability.

  15. Non-aqueous Isorefractive Pickering Emulsions

    PubMed Central

    2015-01-01

    Non-aqueous Pickering emulsions of 16–240 μm diameter have been prepared using diblock copolymer worms with ethylene glycol as the droplet phase and an n-alkane as the continuous phase. Initial studies using n-dodecane resulted in stable emulsions that were significantly less turbid than conventional water-in-oil emulsions. This is attributed to the rather similar refractive indices of the latter two phases. By utilizing n-tetradecane as an alternative oil that almost precisely matches the refractive index of ethylene glycol, almost isorefractive ethylene glycol-in-n-tetradecane Pickering emulsions can be prepared. The droplet diameter and transparency of such emulsions can be systematically varied by adjusting the worm copolymer concentration. PMID:25844544

  16. Destabilization of emulsions by natural minerals.

    PubMed

    Yuan, Songhu; Tong, Man; Wu, Gaoming

    2011-09-15

    This study developed a novel method to destabilize emulsions and recycle oils, particularly for emulsified wastewater treatment. Natural minerals were used as demulsifying agents, two kinds of emulsions collected from medical and steel industry were treated. The addition of natural minerals, including artificial zeolite, natural zeolite, diatomite, bentonite and natural soil, could effectively destabilize both emulsions at pH 1 and 60 °C. Over 90% of chemical oxygen demand (COD) can be removed after treatment. Medical emulsion can be even destabilized by artificial zeolite at ambient temperature. The mechanism for emulsion destabilization by minerals was suggested as the decreased electrostatic repulsion at low pH, the enhanced gathering of oil microdroplets at elevated temperature, and the further decreased surface potential by the addition of minerals. Both flocculation and coalescence were enhanced by the addition of minerals at low pH and elevated temperature.

  17. Characterization of Y2BaCuO5 nanoparticles synthesized by nano-emulsion method

    NASA Astrophysics Data System (ADS)

    Li, Fang; Vipulanandan, Cumaraswamy

    2007-10-01

    Nanoscale yttrium-barium-copper oxide (Y2BaCuO5, Y211) particles were synthesized using the emulsion method and the solution method. The basic water-in-oil (w/o) emulsion system consisted of n-octane (continuous oil phase), cetyltrimethylammonium bromide (cationic surfactant), butanol (cosurfactant) and water. The composition of the emulsion system was varied and characterized by measuring the conductivity of the solutions and droplet size. The droplet size of emulsion was determined by using the dynamic light scattering method. The water content, cosurfactant content, and surfactant/ n-octane ratio affected the droplet size which was in the range of 3-8 nm, and hence the w/o emulsion system was referred to as a nano-emulsion system. A model was used to verify the droplet size. The influence of salt (Y2(NO3)3) content on the droplet size was investigated and the addition of salt reduced the droplet size. The effects of reaction time and temperature on the Y211 particle sizes were also investigated. The particles were characterized using the TEM, SEM, and XRD. Nanoparticles produced by the nano-emulsion method were calcined at 850°C to form the Y211 phase as compared to solid state processing temperature of 1050°C. Based on the TEM analysis, the average diameter of the Y211 particles produced using the nano-emulsion method was in the range of 30-100 nm. The effect of adding 15% Y211 nanoparticles to the superconductor YBCO-123 as flux pinning centers, was investigated, and the transition temperature was reduced by 3 K.

  18. Characterization of Chemically and Thermally Treated Oil-in-Water Heteroaggregates and Comparison to Conventional Emulsions.

    PubMed

    Maier, Christiane; Reichert, Corina L; Weiss, Jochen

    2016-10-01

    Heteroaggregated oil-in-water (O/W) emulsions formed by targeted combination of oppositely charged emulsion droplets were proposed to be used for the modulation of physical properties of food systems, ideally achieving the formation of a particulate 3-dimensional network at comparably low-fat content. In this study, rheological properties of Quillaja saponins (QS), sugar beet pectin (SBP), and whey protein isolate (WPI) stabilized conventional and heteroaggregated O/W emulsions at oil contents of 10% to 60% (w/w) were investigated. Selected systems having an oil content of 30% (w/w) and different particle sizes (d43 ≤ 1.1 or ≥16.7 μm) were additionally subjected to chemical (genipin or glutaraldehyde) and thermal treatments, aiming to increase network stability. Subsequently, their rheological properties and stability were assessed. Yield stresses (τ0 ) of both conventional and heteroaggregated O/W emulsions were found to depend on emulsifier type, oil content, and initial droplet size. For conventional emulsions, high yield stresses were only observed for SBP-based emulsions (τ0 ,SBP approximately 157 Pa). Highest yield stresses of heteroaggregates were observed when using small droplets stabilized by SBP/WPI (approximately 15.4 Pa), being higher than those of QS/WPI (approximately 1.6 Pa). Subsequent treatments led to significant alterations in rheological properties for SBP/WPI systems, with yield stresses increasing 29-fold (glutaraldehyde) and 2-fold (thermal treatment) compared to untreated heteroaggregates, thereby surpassing yield stresses of similarly treated conventional SBP emulsions. Genipin-driven treatments proved to be ineffective. Results should be of interest to food manufacturers wishing to design viscoelastic food emulsion based systems at lower oil droplet contents.

  19. Amino acid isotopic analysis in agricultural systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A relatively new approach to stable isotopic analysis—referred to as compound-specific isotopic analysis (CSIA)—has emerged, centering on the measurement of 15N:14N ratios in amino acids (glutamic acid and phenylalanine). CSIA has recently been used to generate trophic position estimates among anima...

  20. Oxidative Stability of Granola Bars Enriched with Multilayered Fish Oil Emulsion in the Presence of Novel Brown Seaweed Based Antioxidants.

    PubMed

    Hermund, Ditte B; Karadağ, Ayşe; Andersen, Ulf; Jónsdóttir, Rósa; Kristinsson, Hordur G; Alasalvar, Cesarettin; Jacobsen, Charlotte

    2016-11-09

    Fucus vesiculosus extracts that have both radical scavenging activity and metal chelating ability in vitro were used as natural antioxidant in granola bars enriched with fish oil emulsion by using primary and secondary emulsion systems stabilized by sodium caseinate alone and sodium caseinate-chitosan. The bars were stored at 20 °C and evaluated over a period of 10 weeks by measuring the development of primary and secondary oxidation products. The samples prepared with secondary emulsion system developed less oxidation products probably due to increased interfacial layer thickness that would act as a barrier to the penetration and diffusion of molecular species that promote oxidation. The positive charge of oil droplets in the secondary emulsion may also inhibit iron-lipid interaction through electrostatic repulsion. Additional protection against lipid oxidation was obtained when fish oil emulsions were added to the granola bars especially in combination with acetone and ethanol extracts of Fucus vesiculosus.

  1. Regulation of the plasma amino acid profile by leucine via the system L amino acid transporter.

    PubMed

    Zhen, Hongmin; Nakamura, Koichi; Kitaura, Yasuyuki; Kadota, Yoshihiro; Ishikawa, Takuya; Kondo, Yusuke; Xu, Minjun; Shimomura, Yoshiharu

    2015-01-01

    Plasma concentrations of amino acids reflect the intracellular amino acid pool in mammals. However, the regulatory mechanism requires clarification. In this study, we examined the effect of leucine administration on plasma amino acid profiles in mice with and without the treatment of 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH) or rapamycin as an inhibitor of system L or mammalian target of rapamycin complex 1, respectively. The elevation of plasma leucine concentration after leucine administration was associated with a significant decrease in the plasma concentrations of isoleucine, valine, methionine, phenylalanine, and tyrosine; BCH treatment almost completely blocked the leucine-induced decrease in plasma amino acid concentrations. Rapamycin treatment had much less effects on the actions of leucine than BCH treatment. These results suggest that leucine regulates the plasma concentrations of branched-chain amino acids, methionine, phenylalanine, and tyrosine, and that system L amino acid transporters are involved in the leucine action.

  2. Arresting relaxation in Pickering Emulsions

    NASA Astrophysics Data System (ADS)

    Atherton, Tim; Burke, Chris

    2015-03-01

    Pickering emulsions consist of droplets of one fluid dispersed in a host fluid and stabilized by colloidal particles absorbed at the fluid-fluid interface. Everyday materials such as crude oil and food products like salad dressing are examples of these materials. Particles can stabilize non spherical droplet shapes in these emulsions through the following sequence: first, an isolated droplet is deformed, e.g. by an electric field, increasing the surface area above the equilibrium value; additional particles are then adsorbed to the interface reducing the surface tension. The droplet is then allowed to relax toward a sphere. If more particles were adsorbed than can be accommodated by the surface area of the spherical ground state, relaxation of the droplet is arrested at some non-spherical shape. Because the energetic cost of removing adsorbed colloids exceeds the interfacial driving force, these configurations can remain stable over long timescales. In this presentation, we present a computational study of the ordering present in anisotropic droplets produced through the mechanism of arrested relaxation and discuss the interplay between the geometry of the droplet, the dynamical process that produced it, and the structure of the defects observed.

  3. Thoron-tartaric acid systems for spectrophotometric determination of thorium

    USGS Publications Warehouse

    Grimaldi, F.S.; Fletcher, M.H.

    1956-01-01

    Thoron is commonly used for the spectrophotometric determination of thorium. An undesirable feature of its use is its high sensitivity to zirconium. This study describes the use of tartaric acid as a masking reagent for zirconium. Three tartaric acid-thoron systems, developed for the determination of thorium, differ with respect to the concentrations of thoron and tartaric acid. Mesotartaric acid, used in one of the systems, is most effective in masking zirconium. The behavior of rarer elements, usually associated with thorium ores, is determined in two systems, and a dilution method is described for the direct determination of thorium in monazite concentrates.

  4. Plasma lipid levels in preterm neonates receiving parenteral fat emulsions.

    PubMed Central

    Hilliard, J L; Shannon, D L; Hunter, M A; Brans, Y W

    1983-01-01

    Concentrations of various plasma lipid fractions were determined during 96 hours of continuous parenteral infusions of lipid emulsions in 10 normally-grown neonates whose birth-weights ranged from 960 to 1760 g and whose gestational ages ranged from 26 to 32 weeks. Total lipid, triglyceride, free glycerol, and free fatty acid concentrations were measured. During lipid infusions, mean plasma concentrations of all lipid fractions increased above the mean preinfusion values if 2 g/kg a day or more of lipid emulsion was used. There were no further significant increases in mean plasma lipid levels if the infused dosage was increased to 3 or 4 g/kg a day. At these higher infusion rates however, there were considerable individual variations. The only neonate less than 27 weeks of gestation had plasma lipid levels severalfold higher than any of his peers, his plasma was frankly creamy on visual inspection, and the study had to be stopped. Further investigations are needed to determine the optimal modalities of parenteral nutrition with fat emulsions. PMID:6402989

  5. Functional properties of ultrasonically generated flaxseed oil-dairy emulsions.

    PubMed

    Shanmugam, Akalya; Ashokkumar, Muthupandian

    2014-09-01

    This study reports on the functional properties of 7% flaxseed oil/milk emulsion obtained by sonication (OM) using 20 kHz ultrasound (US) at 176 W for 1-8 min in two different delivery formulae, viz., ready-to-drink (RTD) and lactic acid gel. The RTD emulsions showed no change in viscosity after sonication for up to 8 min followed by storage up to a minimum of 9 days at 4±2 °C. Similarly, the oxidative stability of the RTD emulsion was studied by measuring the conjugated diene hydroperoxides (CD). The CD was unaffected after 8 min of ultrasonic processing. The safety aspect of US processing was evaluated by measuring the formation of CD at different power levels. The functional properties of OM gels were evaluated by small and large scale deformation studies. The sonication process improved the gelation characteristics, viz., decreased gelation time, increased elastic nature, decreased syneresis and increased gel strength. The presence of finer sono-emulsified oil globules, stabilized by partially denatured whey proteins, contributed to the improvements in the gel structure in comparison to sonicated and unsonicated pasteurized homogenized skim milk (PHSM) gels. A sono-emulsification process of 5 min followed by gelation for about 11 min can produce gels of highest textural attibutes.

  6. Phase holograms in silver halide emulsions without a bleaching step

    NASA Astrophysics Data System (ADS)

    Belendez, Augusto; Madrigal, Roque F.; Pascual, Inmaculada V.; Fimia, Antonio

    2000-03-01

    Phase holograms in holographic emulsions are usually obtained by two bath processes (developing and bleaching). In this work we present a one step method to reach phase holograms with silver-halide emulsions. Which is based on the variation of the conditions of the typical developing processes of amplitude holograms. For this, we have used the well-known chemical developer, AAC, which is composed by ascorbic acid as a developing agent and sodium carbonate anhydrous as accelerator. Agfa 8E75 HD and BB-640 plates were used to obtain these phase gratings, whose colors are between yellow and brown. In function of the parameters of this developing method the resulting diffraction efficiency and optical density of the diffraction gratings were studied. One of these parameters studied is the influence of the grain size. In the case of Agfa plates diffraction efficiency around 18% with density < 1 has been reached, whilst with the BB-640 emulsion, whose grain is smaller than that of the Agfa, diffraction efficiency near 30% has been obtained. The resulting gratings were analyzed through X-ray spectroscopy showing the differences of the structure of the developed silver when amplitude and transmission gratings are obtained. The angular response of both (transmission and amplitude) gratings were studied, where minimal transmission is showed at the Braggs angle in phase holograms, whilst a maximal value is obtained in amplitude gratings.

  7. Tested Demonstrations: Color Oscillations in the Formic Acid-Nitric Acid-Sulfuric Acid System.

    ERIC Educational Resources Information Center

    Raw, C. J. G.; And Others

    1983-01-01

    Presented are procedures for demonstrating the production of color oscillations when nitric acid is added to a formic acid/concentrated sulfuric acid mixture. Because of safety considerations, "Super-8" home movie of the color changes was found to be satisfactory for demonstration purposes. (JN)

  8. Study and modeling of the rheological properties of concentrated water-in-oil emulsions

    SciTech Connect

    Koroleva, M.Yu.; Yurtov, E.V.

    1994-07-01

    Study of the rheological curves of concentrated water-in-oil emulsions indicates that such systems behave like non-Newtonian pseudo-plastic liquids. A number of mathematical models for rheological curves: Chong, Frankel-Acrivos, Ostwald-Weil, Bingham, Stainer, Ferry, Haven, Ellis, and Meter models are considered. The regions of the model adequacy for rheological curves of emulsions with different contents of the dispersed phase are determined. It was shown that only the Ellis model adequately describes the complete rheological curves of concentrated water-in-oil emulsions of the studied composition. Therefore, this model can be applied to the prediction of the viscosity values for emulsions with various phase ratios.

  9. Light controlled reversible inversion of nanophosphor-stabilized Pickering emulsions for biphasic enantioselective biocatalysis.

    PubMed

    Chen, Zhaowei; Zhou, Li; Bing, Wei; Zhang, Zhijun; Li, Zhenhua; Ren, Jinsong; Qu, Xiaogang

    2014-05-21

    In this work, by utilizing photochromic spiropyrans conjugated upconversion nanophosphors, we have successfully prepared NIR/visible light tuned interfacially active nanoparticles for the formulation of Pickering emulsions with reversible inversion properties. By loading a model enantioselective biocatalytic active bacteria Alcaligenes faecalis ATCC 8750 in the aqueous phase, we demonstrated for the first time that the multifunctional Pickering emulsion not only highly enhanced its catalytic performance but also relieved the substrate inhibition effect. In addition, product recovery, and biocatalysts and colloid emulsifiers recycling could be easily realized based on the inversion ability of the Pickering emulsion. Most importantly, the utilization of NIR/visible light to perform the reversible inversion without any chemical auxiliaries or temperature variation showed little damage toward the biocatalysts, which was highlighted by the high catalytic efficiency and high enantioselectivity even after 10 cycles. The NIR/visible light controlled Pickering emulsion showed promising potential as a powerful technique for biocatalysis in biphasic systems.

  10. Influence of non-migratory metal-chelating active packaging film on food quality: impact on physical and chemical stability of emulsions.

    PubMed

    Tian, Fang; Decker, Eric A; McClements, D Julian; Goddard, Julie M

    2014-05-15

    Previously, we developed a novel metal-chelating packaging film (PP-g-PAA) by grafting acrylic acid (AA) monomer from polypropylene (PP) film surface, and demonstrated its potential in controlling iron-promoted lipid oxidation. Herein, we further established the industrial practicality of this active film. Specifically, the influence of film surface area-to-product volume ratio (SA/V) and product pH on the application of the film was investigated using an oil-in-water emulsion system. The films equally inhibited lipid oxidation throughout the range of SA/V ratios tested (2-8 cm(2)/ml). PP-g-PAA films were most effective at pH 7.0, and the activity decreased with decreasing pH. The particle size examination of emulsions indicated no adverse influence from the active film on the stability of this emulsion system. FTIR analysis suggested a non-migratory nature of PP-g-PAA films. These results provide fundamental knowledge that will facilitate the application of this effective and economical active packaging film in the food industry.

  11. Emulsion package and method of mixing the emulsion

    SciTech Connect

    Snyder, R.G.; Brenneman, S.; Clancy, J.J.

    1984-08-28

    A coal tar emulsion driveway sealer is packaged in a sealed bag. The volume of sealer is less than half the capacity of the bag and the bag is substantially completely evacuated but for the sealer. The separated sealer is mixed by compressing the sides of the bag to induce turbulent flow of the paste and liquid for hydraulic mixing thereof. The sealer may be dispensed at a controlled rate without spattering by cutting a corner from the bag to provide a pour spout. The bag with the sealer may be contained in a carton. The bag membrane comprises an aluminum layer vapor deposited on polyester. Those two layers are sandwiched between layers of EVA copolymer.

  12. Ethylcellulose: a new type of emulsion stabilizer.

    PubMed

    Melzer, Eva; Kreuter, Jörg; Daniels, Rolf

    2003-07-01

    Cellulose ethers, in particular hypromellose, represent an interesting alternative when emulsions have to be stabilized avoiding conventional low molecular weight surfactants. So far this option has been only described for the formulation of oil-in-water (o/w) emulsions. Since surfactant-free water-in-oil (w/o) emulsions seem to be also attractive as drug carriers, ethyl cellulose, an oil-soluble cellulose derivative, was studied for its ability to stabilize w/o emulsions. Measurements of the interfacial tension confirmed that ethylcellulose was positively adsorbed at the water/oil interface with diverse lipids. Appearance of model emulsions was dependent on the processing temperature. At low temperatures (15 degrees C) cream-like o/w emulsions were obtained. Processing at 30 degrees C yielded fluid w/o-lotions. Investigation of the microstructure showed that the surface of the emulsion droplets was covered with particles which formed a mechanical barrier. These colloidal particles were shown to be a precipitate of ethylcellulose which forms when the polymer which was dissolved in the lipid phase comes into contact with water. Thus, ethylcellulose was demonstrated to represent a new type of particulate polymeric emulsifier.

  13. Using emulsion inversion in industrial processes.

    PubMed

    Salager, Jean-Louis; Forgiarini, Ana; Márquez, Laura; Peña, Alejandro; Pizzino, Aldo; Rodriguez, María P; Rondón-González, Marianna

    2004-05-20

    Emulsion inversion is a complex phenomenon, often perceived as an instability that is essentially uncontrollable, although many industrial processes make use of it. A research effort that started 2 decades ago has provided the two-dimensional and three-dimensional description, the categorization and the theoretical interpretation of the different kinds of emulsion inversion. A clear-cut phenomenological approach is currently available for understanding its characteristics, the factors that influence it and control it, the importance of fine-tuning the emulsification protocol, and the crucial occurrence of organized structures such as liquid crystals or multiple emulsions. The current know-how is used to analyze some industrial processes involving emulsion inversion, e.g. the attainment of a fine nutrient or cosmetic emulsion by temperature or formulation-induced transitional inversion, the preparation of a silicone oil emulsion by catastrophic phase inversion, the manufacture of a viscous polymer latex by combined inversion and the spontaneous but enigmatic inversion of emulsions used in metal working operations such as lathing or lamination.

  14. Continuous-flow free acid monitoring method and system

    DOEpatents

    Strain, James E.; Ross, Harley H.

    1981-01-01

    A free acid monitoring method and apparatus is provided for continuously measuring the excess acid present in a process stream. The disclosed monitoring system and method is based on the relationship of the partial pressure ratio of water and acid in equilibrium with an acid solution at constant temperature. A portion of the process stream is pumped into and flows through the monitor under the influence of gravity and back to the process stream. A continuous flowing sample is vaporized at a constant temperature and the vapor is subsequently condensed. Conductivity measurements of the condensate produces a nonlinear response function from which the free acid molarity of the sample process stream is determined.

  15. Continuous-flow free acid monitoring method and system

    DOEpatents

    Strain, J.E.; Ross, H.H.

    1980-01-11

    A free acid monitoring method and apparatus is provided for continuously measuring the excess acid present in a process stream. The disclosed monitoring system and method is based on the relationship of the partial pressure ratio of water and acid in equilibrium with an acid solution at constant temperature. A portion of the process stream is pumped into and flows through the monitor under the influence of gravity and back to the process stream. A continuous flowing sample is vaporized at a constant temperature and the vapor is subsequently condensed. Conductivity measurements of the condensate produces a nonlinear response function from which the free acid molarity of the sample process stream is determined.

  16. Three-dimensional molecular mapping of a multiple emulsion by means of CARS microscopy.

    PubMed

    Meyer, Tobias; Akimov, Denis; Tarcea, Nicolae; Chatzipapadopoulos, Susana; Muschiolik, Gerald; Kobow, Jens; Schmitt, Michael; Popp, Jürgen

    2008-02-07

    Multiple emulsions consisting of water droplets dispersed in an oil phase containing emulsifier which is emulsified in an outer water phase (W/O/W) are of great interest in pharmacology for developing new drugs, in the nutrition sciences for designing functional food, and in biology as model systems for cell organelles such as liposomes. In the food industry multiple emulsions with high sugar content in the aqueous phase can be used for the production of sweets, because the high sugar content prevents deterioration. However, for these emulsions the refractive indexes of oil and aqueous phase are very similar. This seriously impedes the analysis of these emulsions, e.g., for process monitoring, because microscopic techniques based on transmission or reflection do not provide sufficient contrast. We have characterized the inner dispersed phase of concentrated W/O/W emulsions with the same refractive index of the three phases by micro Raman spectroscopy and investigated the composition and molecular distribution in water-oil-water emulsions by means of three-dimensional laser scanning CARS (coherent anti-Stokes Raman scattering) microscopy. CARS microscopy has been used to study water droplets dispersed in oil droplets at different Raman resonances to visualize different molecular species. Water droplets with a diameter of about 700 nm could clearly be visualized. The advantages of CARS microscopy for studying this particular system are emphasized by comparing this microscopic technique with conventional confocal reflection and transmission microscopies.

  17. Highly stable phase change material emulsions fabricated by interfacial assembly of amphiphilic block copolymers during phase inversion.

    PubMed

    Park, Hanhee; Han, Dong Wan; Kim, Jin Woong

    2015-03-10

    This study introduced a robust and promising approach to fabricate highly stable phase change material (PCM) emulsions consisting of n-tetradecane as a dispersed phase and a mixture of meso-2,3-butanediol (m-BDO) and water as a continuous phase. We showed that amphiphilic poly(ethylene oxide)-b-poly(ε-caprolactone) block copolymers assembled to form a flexible but tough polymer membrane at the interface during phase inversion from water-in-oil emulsion to oil-in-water emulsion, thus remarkably improving the emulsion stability. Although the incorporation of m-BDO into the emulsion lowered the phase changing enthalpy, it provided a useful means to elevate the melting temperature of the emulsions near to 15 °C. Interestingly, supercooling was commonly observed in our PCM emulsions. We attributed this to the fact that the PCM molecules confined in submicron-scale droplets could not effectively nucleate to grow molecular crystals. Moreover, the presence of m-BDO in the continuous phase rather dominated the heat emission of the emulsion system during freezing, which made the supercooling more favorable.

  18. Dynamical and structural signatures of the glass transition in emulsions

    NASA Astrophysics Data System (ADS)

    Zhang, Chi; Gnan, Nicoletta; Mason, Thomas G.; Zaccarelli, Emanuela; Scheffold, Frank

    2016-09-01

    We investigate structural and dynamical properties of moderately polydisperse emulsions across an extended range of droplet volume fractions ϕ, encompassing fluid and glassy states up to jamming. Combining experiments and simulations, we show that when ϕ approaches the glass transition volume fraction {φg} , dynamical heterogeneities and amorphous order arise within the emulsion. In particular, we find an increasing number of clusters of particles having five-fold symmetry (i.e. the so-called locally favoured structures, LFS) as ϕ approaches {φg} , saturating to a roughly constant value in the glassy regime. However, contrary to previous studies, we do not observe a corresponding growth of medium-range crystalline order; instead, the emergence of LFS is decoupled from the appearance of more ordered regions in our system. We also find that the static correlation lengths associated with the LFS and with the fastest particles can be successfully related to the relaxation time of the system. By contrast, this does not hold for the length associated with the orientational order. Our study reveals the existence of a link between dynamics and structure close to the glass transition even in the absence of crystalline precursors or crystallization. Furthermore, the quantitative agreement between our confocal microscopy experiments and Brownian dynamics simulations indicates that emulsions are and will continue to be important model systems for the investigation of the glass transition and beyond.

  19. The use of emulsions for the determination of methylmercury and inorganic mercury in fish-eggs oil by cold vapor generation in a flow injection system with atomic absorption spectrometric detection.

    PubMed

    Burguera, J L; Quintana, I A; Salager, J L; Burguera, M; Rondón, C; Carrero, P; Anton de Salager, R; Petit de Peña, Y

    1999-04-01

    An on-line time based injection system used in conjunction with cold vapor generation atomic absorption spectrometry and microwave-aided oxidation with potassium persulfate has been developed for the determination of the different mercury species in fish-eggs oil samples. A three-phase surfactant-oil-water emulsion produced an advantageous flow when a peristaltic pump was used to introduce the highly viscous sample into the system. The optimum proportion of the oil-water mixture ratio was 2:3 v/v with a Tween 20 surfactant concentration in the emulsion of 0.008% v/v. Inorganic mercury was determined after reduction with sodium borohydride while total mercury was determined after an oxidation step with persulfate prior to the reduction step to elemental mercury with the same reducing agent. The difference between total and inorganic mercury determined the organomercury content in samples. A linear calibration graph was obtained in the range 0.1-20 micrograms l-1 of Hg2+ by injecting 0.7 ml of samples. The detection limits based on 3 sigma of the blank signals were 0.11 and 0.12 microgram l-1 for total and inorganic mercury, respectively. The relative standard deviation of ten independent measurements were 2.8 and 2.2% for 10 micrograms l-1 and 8.8 and 9.0% for 0.1 microgram l-1 amounts of total and inorganic mercury, respectively. The recoveries of 0.3, 0.6 and 8 micrograms l-1 of inorganic and organic mercury added to fish-eggs oil samples ranged from 93.0 to 94.8% and from 100 to 106%, respectively. Good agreement with those values obtained for total mercury content in real samples by electrothermal atomic absorption spectrometry was also obtained, differences between mean values were < 7%. With the proposed procedure, 22 proteropterous catfish-eggs oil samples from the northwestern coast of Venezuela were measured; while the organic mercury lay in the range 2.0 and 3.3 micrograms l-1, inorganic mercury was not detected.

  20. Nucleic acid detection system and method for detecting influenza

    DOEpatents

    Cai, Hong; Song, Jian

    2015-03-17

    The invention provides a rapid, sensitive and specific nucleic acid detection system which utilizes isothermal nucleic acid amplification in combination with a lateral flow chromatographic device, or DNA dipstick, for DNA-hybridization detection. The system of the invention requires no complex instrumentation or electronic hardware, and provides a low cost nucleic acid detection system suitable for highly sensitive pathogen detection. Hybridization to single-stranded DNA amplification products using the system of the invention provides a sensitive and specific means by which assays can be multiplexed for the detection of multiple target sequences.

  1. Evolutionary systems biology of amino acid biosynthetic cost in yeast.

    PubMed

    Barton, Michael D; Delneri, Daniela; Oliver, Stephen G; Rattray, Magnus; Bergman, Casey M

    2010-08-17

    Every protein has a biosynthetic cost to the cell based on the synthesis of its constituent amino acids. In order to optimise growth and reproduction, natural selection is expected, where possible, to favour the use of proteins whose constituents are cheaper to produce, as reduced biosynthetic cost may confer a fitness advantage to the organism. Quantifying the cost of amino acid biosynthesis presents challenges, since energetic requirements may change across different cellular and environmental conditions. We developed a systems biology approach to estimate the cost of amino acid synthesis based on genome-scale metabolic models and investigated the effects of the cost of amino acid synthesis on Saccharomyces cerevisiae gene expression and protein evolution. First, we used our two new and six previously reported measures of amino acid cost in conjunction with codon usage bias, tRNA gene number and atomic composition to identify which of these factors best predict transcript and protein levels. Second, we compared amino acid cost with rates of amino acid substitution across four species in the genus Saccharomyces. Regardless of which cost measure is used, amino acid biosynthetic cost is weakly associated with transcript and protein levels. In contrast, we find that biosynthetic cost and amino acid substitution rates show a negative correlation, but for only a subset of cost measures. In the economy of the yeast cell, we find that the cost of amino acid synthesis plays a limited role in shaping transcript and protein expression levels compared to that of translational optimisation. Biosynthetic cost does, however, appear to affect rates of amino acid evolution in Saccharomyces, suggesting that expensive amino acids may only be used when they have specific structural or functional roles in protein sequences. However, as there appears to be no single currency to compute the cost of amino acid synthesis across all cellular and environmental conditions, we conclude that

  2. Using the pseudophase kinetic model to interpret chemical reactivity in ionic emulsions: determining antioxidant partition constants and interfacial rate constants.

    PubMed

    Gu, Qing; Bravo-Díaz, Carlos; Romsted, Laurence S

    2013-06-15

    Kinetic results obtained in cationic and anionic emulsions show for the first time that pseudophase kinetic models give reasonable estimates of the partition constants of reactants, here t-butylhydroquinone (TBHQ) between the oil and interfacial region, P(O)(I), and the water and interfacial region, P(W)(I), and of the interfacial rate constant, k(I), for the reaction with an arenediazonium ion in emulsions containing a 1:1 volume ratio of a medium chain length triglyceride, MCT, and aqueous acid or buffer. The results provide: (a) an explanation for the large difference in pH, >4 pH units, required to run the reaction in CTAB (pH 1.54, added HBr) and SDS (pH 5.71, acetate buffer) emulsions; (b) reasonable estimates of PO(I) and k(I) in the CTAB emulsions; (c) a sensible interpretation of added counterion effects based on ion exchange in SDS emulsions (Na(+)/H3O(+) ion exchange in the interfacial region) and Donnan equilibrium in CTAB emulsions (Br(-) increasing the interfacial H3O(+)); and (d) the significance of the effect of the much greater solubility of TBHQ in MCT versus octane, 1000/1, as the oil. These results should aid in interpreting the effects of ionic surfactants on chemical reactivity in emulsions in general and in selecting the most efficient antioxidant for particular food applications.

  3. Dielectrophoresis of reverse phase emulsions.

    PubMed

    Flores-Rodriguez, N; Bryning, Z; Markx, G H

    2005-08-01

    Reverse miniemulsions, emulsions of droplets of size 200 nm-1 microm of a polar liquid dispersed in an apolar continuous liquid phase, exhibit strong electrokinetic responses in low-frequency electric fields. The electrokinetic behaviour of a reverse miniemulsion, previously developed for use as electronic paper, has been investigated under static and flow conditions, in uniform and non-uniform electric fields. Results reveal that when using frequencies lower than 10 Hz strong aggregation of the droplets occurs. In uniform electric fields, under static conditions, droplets reversibly aggregate into honeycomb-like or irregular aggregates. Under flow conditions, droplets aggregate into approximately equidistant streams. In non-uniform electric fields the droplets reversibly aggregate in high-field regions, and can be guided along regions of high field strength in a flow. The potential of the technique for the formation of structured materials is discussed.

  4. Poly(isobutylene) nanoparticles via cationic polymerization in nonaqueous emulsions.

    PubMed

    Schuster, Thomas; Golling, Florian E; Krumpfer, Joseph W; Wagner, Manfred; Graf, Robert; Alsaygh, Abdulhamid A; Klapper, Markus; Müllen, Klaus

    2015-01-01

    The preparation of poly(isobutylene) (PIB) nanoparticles via cationic emulsion polymerization is presented. As a requirement, an oil-in-perfluoroalkane nonaqueous emulsion is developed, which is inert under the carbocationic polymerization conditions. To stabilize the dichloromethane/hexane droplets in the fluorinated, continuous phase, an amphiphilic block copolymer emulsifier is prepared containing PIB and 1H,1H-perfluoroalkylated poly(pentafluorostyrene) blocks. This system allows for the polymerization of isobutylene with number-average molecular weights (Mn) up to 27,000 g mol(-1). The particle morphologies are characterized via dynamic light scattering and electron microscopy. For Mn > 20,000 g mol(-1), the particles exhibit shape-persistence at room temperature and are ≈100 nm in diameter.

  5. Analysis of relativistic nucleus-nucleus interactions in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1987-01-01

    The development of a computer-assisted method is reported for the determination of the angular distribution data for secondary particles produced in relativistic nucleus-nucleus collisions in emulsions. The method is applied to emulsion detectors that were placed in a constant, uniform magnetic field and exposed to beams of 60 and 200 GeV/nucleon O-16 ions at the Super Proton Synchrotron (SPS) of the European Center for Nuclear Research (CERN). Linear regression analysis is used to determine the azimuthal and polar emission angles from measured track coordinate data. The software, written in BASIC, is designed to be machine independent, and adaptable to an automated system for acquiring the track coordinates. The fitting algorithm is deterministic, and takes into account the experimental uncertainty in the measured points. Further, a procedure for using the track data to estimate the linear momenta of the charged particles observed in the detectors is included.

  6. Amino acid auxotrophy as a system of immunological control nodes.

    PubMed

    Murray, Peter J

    2016-02-01

    Cells of the immune system are auxotrophs for most amino acids, including several nonessential ones. Arginine and tryptophan are used within the regulatory immune networks to control proliferation and function through pathways that actively deplete the amino acid from the microenvironment or that create regulatory molecules such as nitric oxide or kynurenines. How immune cells integrate information about essential amino acid supplies and then transfer these signals to growth and activation pathways remains unclear but has potential for pathway discovery about amino sensing. In applied research, strategies to harness amino acid auxotrophy so as to block cancerous lymphocyte growth have been attempted for decades with limited success. Emerging insights about amino acid metabolism may lead to new strategies in clinical medicine whereby both amino acid auxotrophy and the immunoregulatory pathways controlled by amino acids can be manipulated.

  7. Surface Interaction of Water-in-Oil Emulsion Droplets with Interfacially Active Asphaltenes.

    PubMed

    Shi, Chen; Zhang, Ling; Xie, Lei; Lu, Xi; Liu, Qingxia; He, Jiajun; Mantilla, Cesar A; Van den Berg, Frans G A; Zeng, Hongbo

    2017-02-07

    Adsorption of interfacially active components at the water/oil interface plays critical roles in determining the properties and behaviors of emulsion droplets. In this study, the droplet probe atomic force microscopy (AFM) technique was applied, for the first time, to quantitatively study the interaction mechanism between water-in-oil (W/O) emulsion droplets with interfacially adsorbed asphaltenes. The behaviors and stability of W/O emulsion droplets were demonstrated to be significantly influenced by the asphaltene concentration of organic solution where the emulsions were aged, aging time, force load, contact time, and solvent type. Bare water droplets could readily coalesce with each other in oil (i.e., toluene), while interfacially adsorbed asphaltenes could sterically inhibit droplet coalescence and induce interfacial adhesion during separation of the water droplets. For low asphaltene concentration cases, the adhesion increased with increasing asphaltene concentration (≤100 mg/L), but it significantly decreased at relatively high asphaltene concentration (e.g., 500 mg/L). Experiments in Heptol (i.e., mixture of toluene and heptane) showed that the addition of a poor solvent for asphaltenes (e.g., heptane) could enhance the interfacial adhesion between emulsion droplets at relatively low asphaltene concentration but could weaken the adhesion at relatively high asphaltene concentration. This work has quantified the interactions between W/O emulsion droplets with interfacially adsorbed asphaltenes, and the results provide useful implications into the stabilization mechanisms of W/O emulsions in oil production. The methodology in this work can be readily extended to other W/O emulsion systems with interfacially active components.

  8. System for agitating the acid in a lead-acid battery

    DOEpatents

    Weintraub, Alvin; MacCormack, Robert S.

    1987-01-01

    A system and method for agitating the acid in a large lead-sulfuric acid storage battery of the calcium type. An air-lift is utilized to provide the agitation. The air fed to the air-lift is humidified prior to being delivered to the air-lift.

  9. Behaviour of formula emulsions containing hydrolysed whey protein and various lecithins.

    PubMed

    Tirok, S; Scherze, I; Muschiolik, G

    2001-07-01

    Formula emulsion systems are used as enteral, sports and health products. In some formulas addition of hydrolysed protein is necessary to guarantee ease of digestion and hypoallergenicity. In the low fat emulsion model an increase in the content of lecithin (phospholipid mixture) was required, in consideration of the advice of the Food and Nutrition Board (USA) for choline supplementation. The individual and interactive effects of whey protein isolate (WPI) or hydrolysate (WPH) (3.7 and 4.9% w/w), unmodified deoiled or hydrolysed lecithin (0.48 or 0.7% w/w) and carbohydrate in the form of maltodextrin with dextrose equivalent (DE) 18.5 or glucose syrup with DE 34 (11% w/w) on the properties of formula emulsions with 4% v/w sunflower oil, were investigated using a full factorial design. The emulsions were characterised by particle size distribution, coalescence stability, creaming rate, and also surface protein and lecithin concentration. WPI-containing emulsions proved to be stable against coalescence and showed only little creaming after 1 and 7 days standing. There was a significant increase in the mean droplet size and a significant deterioration of coalescence and creaming stability when WPH instead of WPI was used as the protein source, due to the lower number of large peptides and lower surface activity of the WPH. Increasing the WPH concentration led to an increase in oil droplet size and further deterioration of the stability of the emulsions. The starch hydrolysate and lecithin also significantly influenced the emulsion properties. Their influence was less strong when the emulsion contained WPI. Under the conditions used WPH-based emulsions were more stable, in terms of creaming and coalescence, when a low level of protein was used in conjunction with hydrolysed lecithin and glucose syrup. Oil droplets in emulsions containing unmodified lecithin in either the continuous or disperse phase and WPH in the continuous phase were very sensitive to coalescence

  10. Highly concentrated emulsions: 1. Average drop size determination by analysis of incoherent polarized steady light transport.

    PubMed

    Paruta-Tuarez, Emilio; Fersadou, Hala; Sadtler, Véronique; Marchal, Philippe; Choplin, Lionel; Baravian, Christophe; Castel, Christophe

    2010-06-01

    The analysis of incoherent polarized steady light transport is reported as a convenient technique for the drop size determination in highly concentrated oil-in-water emulsions. The studied system consists in heptane-in-water emulsions stabilized with a copolymeric surfactant (Synperonic PE®/L64). Hundred grams of parent emulsions, at two volume fractions of dispersed phase (φ=0.958 and 0.937) were prepared using a semi-batch process. Then, they were diluted with the aqueous phase to obtain volume fractions ranging from 0.886 to 0.958. The use of a copolymeric surfactant allows the dilution of the highly concentrated emulsions without any change in the particle size distribution as confirmed by laser diffraction measurements. We found that the polarization technique allows the determination of the film thickness between water drops rather than their sizes. Consequently, we propose a geometrical relationship to determine an average drop size from the film thickness. The sensitivity of this alternative technique to detect changes in average drop size was studied by changing some process and formulation parameters. Drop size determination in highly concentrated emulsions via this method is useful since the measurement protocol neither involves dilution nor induces structural changes in the emulsion.

  11. Carbon Dioxide-Water Emulsions for Enhanced Oil Recovery and Permanent Sequestration of Carbon Dioxide

    SciTech Connect

    Ryan, David; Golomb, Dan; Shi, Guang; Shih, Cherry; Lewczuk, Rob; Miksch, Joshua; Manmode, Rahul; Mulagapati, Srihariraju; Malepati, Chetankurmar

    2011-09-30

    This project involves the use of an innovative new invention Particle Stabilized Emulsions (PSEs) of Carbon Dioxide-in-Water and Water-in-Carbon Dioxide for Enhanced Oil Recovery (EOR) and Permanent Sequestration of Carbon Dioxide. The EOR emulsion would be injected into a semi-depleted oil reservoir such as Dover 33 in Otsego County, Michigan. It is expected that the emulsion would dislocate the stranded heavy crude oil from the rock granule surfaces, reduce its viscosity, and increase its mobility. The advancing emulsion front should provide viscosity control which drives the reduced-viscosity oil toward the production wells. The make-up of the emulsion would be subsequently changed so it interacts with the surrounding rock minerals in order to enhance mineralization, thereby providing permanent sequestration of the injected CO{sub 2}. In Phase 1 of the project, the following tasks were accomplished: 1. Perform laboratory scale (mL/min) refinements on existing procedures for producing liquid carbon dioxide-in-water (C/W) and water-in-liquid carbon dioxide (W/C) emulsion stabilized by hydrophilic and hydrophobic fine particles, respectively, using a Kenics-type static mixer. 2. Design and cost evaluate scaled up (gal/min) C/W and W/C emulsification systems to be deployed in Phase 2 at the Otsego County semi-depleted oil field. 3. Design the modifications necessary to the present CO{sub 2} flooding system at Otsego County for emulsion injection. 4. Design monitoring and verification systems to be deployed in Phase 2 for measuring potential leakage of CO{sub 2} after emulsion injection. 5. Design production protocol to assess enhanced oil recovery with emulsion injection compared to present recovery with neat CO{sub 2} flooding. 6. Obtain Federal and State permits for emulsion injection. Initial research focused on creating particle stabilized emulsions with the smallest possible globule size so that the emulsion can penetrate even low-permeability crude

  12. Design and development of multiple emulsion for enhancement of oral bioavailability of acyclovir.

    PubMed

    Paul, Sumita; Kumar, Abhinesh; Yedurkar, Pramod; Sawant, Krutika

    2013-11-01

    The objective of this investigation was to design and develop water-in-oil-in-water type multiple emulsions (w/o/w emulsions) entrapping acyclovir for improving its oral bioavailability. Multiple emulsions (MEs) were prepared and optimized using Span-80 and Span-83 as lipophilic surfactant and Brij-35 as hydrophilic surfactant. The physio-chemical properties of the w/o/w emulsions - particle size, viscosity, phase separation (centrifugation test) and entrapment efficiency were measured and evaluated along with macroscopic and microscopic observations to confirm multiple nature, homogeneity and globule size. Stability study, in vitro and ex vivo release studies were performed followed by in vivo studies in rats. Stable w/o/w emulsions with a particle size of 33.098 ± 2.985 µm and 85.25 ± 4.865% entrapment efficiency were obtained. Stability studies showed that the concentration of lipophilic surfactant was very important for stability of MEs. Drug release from the prepared formulations showed initial rapid release followed by a much slower release. In vivo studies in rats indicated prolonged release and better oral bioavailability as compared to drug solution. The overall results of this study show the potential of the w/o/w emulsions as promising drug delivery systems for acyclovir.

  13. Novel anhydrous emulsions: formulation as controlled release vehicles.

    PubMed

    Suitthimeathegorn, Orawan; Jaitely, Vikas; Florence, Alexander T

    2005-07-25

    Novel anhydrous emulsions, which may offer some advantages as depot or reservoir vehicles for lipophilic drugs in controlled delivery systems, were formulated using castor oil as the disperse phase and dimethicone or cyclopentasiloxane as the continuous phase. Among the emulsifiers studied only silicone surfactants (cyclomethicone/dimethicone copolyols) which were miscible in silicone oil stabilized the emulsions. Cyclomethicone/PEG/PPG-18/18 Dimethicone and Cyclopentasiloxane/PEG/PPG-18/18 Dimethicone were more effective in lowering the interfacial tension between castor oil and both dimethicone and cyclopentasiloxane. Emulsions formulated using either of these two surfactants were found to be stable against phase separation and exhibited least globule growth over 168 h. The average particle size was found to be 2-6 microm in these systems formed by probe sonication. Slow release patterns of 3H-dehydroepiandrosterone (DHEA) and 3H-dexamethasone solubilized in the disperse castor oil phase into an aqueous dialyzing medium were observed over 48 h.

  14. Stability assessment of injectable castor oil-based nano-sized emulsion containing cationic droplets stabilized by poloxamer-chitosan emulsifier films.

    PubMed

    Tamilvanan, S; Kumar, B Ajith; Senthilkumar, S R; Baskar, Raj; Sekharan, T Raja

    2010-06-01

    The objectives of the present work were to prepare castor oil-based nano-sized emulsion containing cationic droplets stabilized by poloxamer-chitosan emulgator film and to assess the kinetic stability of the prepared cationic emulsion after subjecting it to thermal processing and freeze-thaw cycling. Presence of cryoprotectants (5%, w/w, sucrose +5%, w/w, sorbitol) improved the stability of emulsions to droplet aggregation during freeze-thaw cycling. After storing the emulsion at 4 degrees C, 25 degrees C, and 37 degrees C over a period of up to 6 months, no significant change was noted in mean diameter of the dispersed oil droplets. However, the emulsion stored at the highest temperature did show a progressive decrease in the pH and zeta potential values, whereas the emulsion kept at the lowest temperatures did not. This indicates that at 37 degrees C, free fatty acids were formed from the castor oil, and consequently, the liberated free fatty acids were responsible for the reduction in the emulsion pH and zeta potential values. Thus, the injectable castor oil-based nano-sized emulsion could be useful for incorporating various active pharmaceutical ingredients that are in size from small molecular drugs to large macromolecules such as oligonucleotides.

  15. Tunable stability of monodisperse secondary O/W nano-emulsions

    NASA Astrophysics Data System (ADS)

    Vecchione, R.; Ciotola, U.; Sagliano, A.; Bianchini, P.; Diaspro, A.; Netti, P. A.

    2014-07-01

    Stable and biodegradable oil in water (O/W) nano-emulsions can have a huge impact on a wide range of bio-applications, from food to cosmetics and pharmaceuticals. Emulsions, however, are immiscible systems unstable over time; polymer coatings are known to be helpful, but an effective procedure to stabilize monodisperse and biodegradable O/W nano-emulsions is yet to be designed. Here, we coat biodegradable O/W nano-emulsions with a molecular layer of biodegradable polyelectrolytes such as polysaccharides - like chitosan - and polypeptides - like polylysine - and effectively re-disperse and densify the polymer coating at high pressure, thus obtaining monodisperse and stable systems. In particular, focusing on chitosan, our tests show that it is possible to obtain unprecedented ultra-stable O/W secondary nano-emulsions (diameter sizes tunable from ~80 to 160 nm and polydispersion indices below 0.1) by combining this process with high concentrations of polymers. Depending on the polymer concentration, it is possible to control the level of coating that results in a tunable stability ranging from a few weeks to several months. The above range of concentrations has been investigated using a fluorescence-based approach with new insights into the coating evolution.Stable and biodegradable oil in water (O/W) nano-emulsions can have a huge impact on a wide range of bio-applications, from food to cosmetics and pharmaceuticals. Emulsions, however, are immiscible systems unstable over time; polymer coatings are known to be helpful, but an effective procedure to stabilize monodisperse and biodegradable O/W nano-emulsions is yet to be designed. Here, we coat biodegradable O/W nano-emulsions with a molecular layer of biodegradable polyelectrolytes such as polysaccharides - like chitosan - and polypeptides - like polylysine - and effectively re-disperse and densify the polymer coating at high pressure, thus obtaining monodisperse and stable systems. In particular, focusing on

  16. Aging properties of Kodak type 101 emulsions

    NASA Technical Reports Server (NTRS)

    Dohne, B.; Feldman, U.; Neupert, W.

    1984-01-01

    Aging tests for several batches of Kodak type 101 emulsion show that storage conditions significantly influence how well the film will maintain its sensitometric properties, with sensitivity and density increasing to a maximum during this period. Any further aging may result in higher fog levels and sensitivity loss. It is noted that storage in an environment free of photographically active compounds allows film property optimization, and that film batches with different sensitivities age differently. Emulsions with maximum 1700-A sensitivity are 2.5 times faster than those at the low end of the sensitivity scale. These sensitive emulsions exhibit significantly accelerated changes in aging properties. Their use in space applications requires careful consideration of time and temperature profiles, encouraging the use of less sensitive emulsions when the controllability of these factors is limited.

  17. Scanning microbeam small-angle X-ray diffraction study of interfacial heterogeneous crystallization of fat crystals in oil-in-water emulsion droplets.

    PubMed

    Arima, S; Ueno, S; Ogawa, A; Sato, K

    2009-09-01

    We performed scanning microbeam small-angle X-ray diffraction (micro-SAXD) experiments, differential scanning calorimetry (DSC) analysis, and optical microscopic observation of palm mid fraction (PMF) crystals in oil-in-water emulsion droplets. The scanning micro-SAXD experiment was performed by irradiating a synchrotron radiation X-ray microbeam having an area of 5 x 5 microm(2) onto different positions on a 50 microm diameter emulsion droplet after the crystallization of PMF by chilling the emulsion at 5 degrees C. The micro-SAXD patterns were recorded with a two-dimensional (2D) detector, which enabled spatial analysis of polymorphic structures and the orientation of lamella planes of PMF crystals at different positions inside the emulsion droplet. Particular attention was paid to compare the crystallization of PMF in two types of emulsion droplets, hydrophilic polyoxyethylene sorbitan mono-oleate (Tween 80) alone (Tween 80 emulsion) and Tween 80 and hydrophobic sucrose palmitic acid oligoester (P-170) (Tween 80+P-170 emulsion). The DSC study revealed that the PMF crystallization temperature in the Tween 80+P-170 emulsion droplets increased by 3 degrees C compared to that of the Tween 80 emulsion because of the effects of the P-170 additive in promoting PMF crystallization. The micro-SAXD studies revealed the following results. (1) The lamella planes of PMF crystals near the outer edges of the droplet in the Tween 80+P-170 emulsion were mostly parallel to an oil-water interface, whereas the lamella planes of PMF crystals were not always aligned with the oil-water interface in the Tween 80 emulsion droplet. (2) The degree of orientation of the lamellar planes of PMF crystals, which was evaluated from the values of full width at half-maximum of 2D micro-SAXD patterns with respect to azimuthal angle extension, was remarkably higher in the Tween 80+P-170 emulsion than in the Tween 80 emulsion. (3) Polymorphic transformation of PMF from alpha to beta' in the Tween 80

  18. Surfactant-enhanced cellulose nanocrystal Pickering emulsions.

    PubMed

    Hu, Zhen; Ballinger, Sarah; Pelton, Robert; Cranston, Emily D

    2015-02-01

    The effect of surfactants on the properties of Pickering emulsions stabilized by cellulose nanocrystals (CNCs) was investigated. Electrophoretic mobility, interfacial tension, confocal microscopy and three-phase contact angle measurements were used to elucidate the interactions between anionic CNCs and cationic alkyl ammonium surfactants didecyldimethylammonium bromide (DMAB) and cetyltrimethylammonium bromide (CTAB). Both surfactants were found to adsorb onto CNCs with concentration-dependent morphology. At low concentrations, individual surfactant molecules adsorbed with alkyl tails pointing outward leading to hydrophobic CNCs. At higher concentrations, above the surfactant's apparent critical micelle concentration, surfactant aggregate morphologies on CNCs were inferred and the hydrophobicity of CNCs decreased. DMAB, which has two alkyl tails, rendered the CNCs more hydrophobic than CTAB which has only a single alkyl tail, at all surfactant concentrations. The change in CNC wettability from surfactant adsorption was directly linked to emulsion properties; adding surfactant increased the emulsion stability, decreased the droplet size, and controlled the internal phase of CNC Pickering emulsions. More specifically, a double transitional phase inversion, from oil-in-water to water-in-oil and back to oil-in-water, was observed for emulsions with CNCs and increasing amounts of DMAB (the more hydrophobic surfactant). With CNCs and CTAB, no phase inversion was induced. This work represents the first report of CNC Pickering emulsions with surfactants as well as the first CNC Pickering emulsions that can be phase inverted. The ability to surface modify CNCs in situ and tailor emulsions by adding surfactants may extend the potential of CNCs to new liquid formulations and extruded/spray-dried materials.

  19. Shear-stabilized emulsion flooding process

    SciTech Connect

    Carpenter, C.W.; Reed, R.L.

    1982-06-29

    Additional amounts of crude oil are recovered from a subterranean formation by flooding with a translucent emulsion comprising an upper- or middle-phase microemulsion as an external phase and a polymer-containing brine solution as an internal phase. The translucent emulsion tends to coalesce into its component phases under conditions of no shear, but is stabilized by low shears such as those imposed on fluids flowing through a subterranean formation.

  20. Tunable Pickering Emulsions with Environmentally Responsive Hairy Silica Nanoparticles.

    PubMed

    Liu, Min; Chen, Xiaoli; Yang, Zongpeng; Xu, Zhou; Hong, Liangzhi; Ngai, To

    2016-11-30

    Surface modification of the nanoparticles using surface anchoring of amphiphilic polymers offers considerable scope for the design of a wide range of brush-coated hybrid nanoparticles with tunable surface wettability that may serve as new class of efficient Pickering emulsifiers. In the present study, we prepared mixed polymer brush-coated nanoparticles by grafting ABC miktoarm star terpolymers consisting of poly(ethylene glycol), polystyrene, and poly[(3-triisopropyloxysilyl)propyl methacrylate] (μ-PEG-b-PS-b-PIPSMA) on the surface of silica nanoparticles. The wettability of the as-prepared nanoparticles can be precisely tuned by a change of solvent or host-guest complexation. (1)H NMR result confirmed that such wettability change is due to the reorganization of the polymer chain at the grafted layer. We show that this behavior can be used for stabilization and switching between water-in-oil (W/O) and oil-in-water (O/W) emulsions. For hairy particles initially dispersed in oil, W/O emulsions were always obtained with collapsed PEG chains and mobile PS chains at the grafted layer. However, initially dispersing the hairy particles in water resulted in O/W emulsions with collapsed PS chains and mobile PEG chains. When a good solvent for both PS and PEG blocks such as toluene was used, W/O emulsions were always obtained no matter where the hairy particles were dispersed. The wettability of the mixed polymer brush-coated silica particles can also be tuned by host-guest complexation between PEG block and α-CD. More importantly, our result showed that surprisingly the resultant mixed brush-coated hairy nanoparticles can be employed for the one-step production of O/W/O multiple emulsions that are not attainable from conventional Pickering emulsifiers. The functionalized hairy silica nanoparticles at the oil-water interface can be further linked together utilizing poly(acrylic acid) as the reversible linker to form supramolecular colloidosomes, which show p

  1. The complexity of prescribing intravenous lipid emulsions.

    PubMed

    Waitzberg, Dan Linetzky; Torrinhas, Raquel Susana

    2015-01-01

    Intravenous lipid emulsions (LEs) are relevant for patients receiving parenteral nutrition because they prevent the depletion of essential fatty acids (FAs) and, as a highly dense energy source, enable the reduction of glucose provision, thereby decreasing the risks of hyperglycemia and hepatic impairment. The prescription of LEs is complex, due mainly to their distinct FA components, which may alter the immune response in different ways and distinctly influence inflammation, oxidative stress and blood coagulation according to their biochemical properties. In addition, an excess of other LE components, such as phospholipids and phytosterols, may be associated with hepatic steatosis and dysfunction. These associations do not represent direct risks or obstacles to LE use in metabolically stable patients but can render the choice of the best LE for hypermetabolic patients difficult. The infusion of LEs according to the available guidelines provides more benefit than harm and should be part of exclusive parenteral nutrition regimens or complement enteral nutrition when appropriate. The patient's metabolic profile should guide the type of FA and amount of lipids that are provided. For critically ill hypermetabolic patients, growing evidence indicates that standard LEs based solely on soybean oil should be avoided in favor of new LEs containing medium-chain triglycerides, olive oil, or fish oil to decrease the provision of potentially oxidative, inflammatory/immunosuppressive, and prothrombotic n-6 FAs. In addition, as sources of eicosapentaenoic and docosahexaenoic acids, LEs containing fish oil may be important for critically ill patients because they allow better modulation of the immune response and likely reduce the length of intensive care unity stay. However, current evidence precludes the recommendation of a specific LE for clinical use in this patient population.

  2. Pickering emulsions stabilized by charged nanoparticles.

    PubMed

    Ridel, Laure; Bolzinger, Marie-Alexandrine; Gilon-Delepine, Nicole; Dugas, Pierre-Yves; Chevalier, Yves

    2016-09-28

    The stabilization of o/w Pickering emulsions in cases of weak adsorption of solid particles at the surface of oil droplets is addressed. Though the adsorption is usually very strong and irreversible when partial wetting conditions are fulfilled, electrostatic repulsions between charged solid particles act against the adsorption. The regime of weak adsorption was reached using charged silica nanoparticles at high pH and low ionic strength. O/w Pickering emulsions of the diisopropyl adipate oil were stabilized by colloidal nanoparticles of Ludox® AS40 consisting of non-aggregated particles of bare silica (hydrophilic). The combination of stability assessment, droplet size and electrokinetic potential measurements at various pH values, adsorption isotherms and cryo-SEM observations of the adsorbed layers disclosed the specificities of the stabilization of Pickering emulsions by adsorption of solid nanoparticles against strong electrostatic repulsions. Not only the long-term stability of emulsions was poor under strong electrostatic repulsions at high pH, but emulsification failed since full dispersion of oil could not be achieved. Emulsion stability was ensured by decreasing electrostatic repulsions by lowering the pH from 9 to 3. Stable emulsions were stabilized by a monolayer of silica particles at 54% coverage of the oil droplet surface at low silica content and an adsorption regime as multilayers was reached at higher concentrations of silica although there was no aggregation of silica in the bulk aqueous phase.

  3. Comparison of the physicochemical properties of MCT-containing fat emulsions in total nutrient admixtures.

    PubMed

    Télessy, I G; Balogh, J; Csempesz, F; Szente, V; Dredán, J; Zelkó, R

    2009-08-01

    The physical stability of two types of MCT-emulsions made by different technologies - physical mixture vs. structured lipids - was studied as a function of storage time and temperature. Particle size analysis, zeta potential and dynamic surface tension measurements were carried out to evaluate the possible changes in the kinetic stability of the emulsions. Our results indicate that the physical mixture technology of MCT-emulsions resulted in impaired physicochemical stability compared to the ones containing structured triglycerides. In the case of structured lipids, both medium and long chain fatty acids can be found in one triglyceride molecule, leading to a favorable interfacial location of structured triglycerides. Besides the advantageous metabolic effects of structured triglycerides, their application is recommended to improve the physical stability of TPN admixtures.

  4. 300 Area waste acid treatment system closure plan. Revision 1

    SciTech Connect

    1996-03-01

    This section provides a description of the Hanford Site, identifies the proposed method of 300 Area Waste Acid Treatment System (WATS) closure, and briefly summarizes the contents of each chapter of this plan.

  5. Influence of interfacial properties on Ostwald ripening in crosslinked multilayered oil-in-water emulsions.

    PubMed

    Zeeb, Benjamin; Gibis, Monika; Fischer, Lutz; Weiss, Jochen

    2012-12-01

    The influence of interfacial crosslinking, layer thickness and layer density on the kinetics of Ostwald ripening in multilayered emulsions at different temperatures was investigated. Growth rates of droplets were measured by monitoring changes in the droplet size distributions of 0.5% (w/w) n-octane, n-decane, and n-dodecane oil-in-water emulsions using static light scattering. Lifshitz-Slyozov-Wagner theory was used to calculate Ostwald ripening rates. A sequential two step process, based on electrostatic deposition of sugar beet pectin onto fish gelatin or whey protein isolate (WPI) interfacial membranes, was used to manipulate the interfacial properties of the oil droplets. Laccase was added to the fish gelatin-beet pectin emulsions to promote crosslinking of adsorbed pectin molecules via ferulic acid groups, whereas heat was induced to promote crosslinking of WPI and helix coil transitions of fish gelatin. Ripening rates of single-layered, double-layered and crosslinked emulsions increased as the chain length of the n-alkanes decreased. Emulsions containing crosslinked fish gelatin-beet pectin coated droplets had lower droplet growth rates (3.1±0.3×10(-26) m(3)/s) than fish gelatin-stabilized droplets (7.3±0.2×10(-26) m(3)/s), which was attributed to the formation of a protective network. Results suggest that physical or enzymatic biopolymer-crosslinking of interfaces may reduce the molecular transport of alkanes between the droplets in the continuous phase.

  6. Controlled release behaviour of protein-loaded microparticles prepared via coaxial or emulsion electrospray.

    PubMed

    Wang, Ying; Yang, Xiaoping; Liu, Wentao; Zhang, Feng; Cai, Qing; Deng, Xuliang

    2013-01-01

    Biodegradable poly (lactic-co-glycolic acid) (PLGA) microparticles are an effective way to achieve sustained drug release. In this study, we investigated a sustained release model of PLGA microparticles with incorporated protein via either emulsion or coaxial electrospray techniques. PLGA (75:25) was used as the carrier, and bovine serum albumin as a model protein. Coaxial electrospray resulted in a type of core-shell structure with mean diameters of 2.41 ± 0.60 µm and a centralised protein distribution within the core. Emulsion electrospray formed bigger microparticles with mean diameters of 22.75 ± 8.05 µm and a heterogeneous protein distribution throughout the microparticles. The coaxial electrospray microparticles presented a much slighter burst release than the emulsion electrospray microparticles. Loading efficiency was significantly higher (p < 0.05) in the coaxial group than emulsion group. This indicated that both emulsion and coaxial electrospray could produce protein-loaded microparticles with sustained release behaviour, but the former revealed a superior approach for drug delivery.

  7. Controlled release behaviour of protein-loaded microparticles prepared via coaxial or emulsion electrospray

    PubMed Central

    Wang, Ying; Yang, Xiaoping; Liu, Wentao; Zhang, Feng; Cai, Qing; Deng, Xuliang

    2013-01-01

    Biodegradable poly (lactic-co-glycolic acid) (PLGA) microparticles are an effective way to achieve sustained drug release. In this study, we investigated a sustained release model of PLGA microparticles with incorporated protein via either emulsion or coaxial electrospray techniques. PLGA (75:25) was used as the carrier, and bovine serum albumin as a model protein. Coaxial electrospray resulted in a type of core–shell structure with mean diameters of 2.41 ± 0.60 µm and a centralised protein distribution within the core. Emulsion electrospray formed bigger microparticles with mean diameters of 22.75 ± 8.05 µm and a heterogeneous protein distribution throughout the microparticles. The coaxial electrospray microparticles presented a much slighter burst release than the emulsion electrospray microparticles. Loading efficiency was significantly higher (p < 0.05) in the coaxial group than emulsion group. This indicated that both emulsion and coaxial electrospray could produce protein-loaded microparticles with sustained release behaviour, but the former revealed a superior approach for drug delivery. PMID:23346923

  8. Dual responsive Pickering emulsions stabilized by constructed core crosslinked polymer nanoparticles via reversible covalent bonds.

    PubMed

    Guo, Huazhang; Yang, Duanguang; Yang, Mei; Gao, Yong; Liu, Yijiang; Li, Huaming

    2016-12-06

    In this study, pH- and glucose-responsive Pickering emulsions stabilized by core crosslinked polymer nanoparticles, which were constructed via reversible covalent bonds, were presented for the first time. Firstly, well-defined PDMA-b-PAPBA (poly(N,N-dimethylacrylamide)-b-poly(3-acrylamidophenylboronic acid)) diblock copolymers were synthesized via sequential reversible addition-fragmentation chain transfer (RAFT) polymerization reactions. By means of complexation of PBA units of PDMA-b-PAPBA with PVA in basic water, core crosslinked polymer nanoparticles (CCPNs) with a core-shell structure were formed. The PAPBA/PVA crosslinked network and PDMA acted as the core and shell, respectively. Because of the reversible B-O chemical bonds in the core, the as-produced CCPNs showed structural transitions in response to the external stimuli involving pH and glucose. Investigation of the interfacial activities revealed that CCPNs exhibited high emulsifying performances, and oil in water (o/w) Pickering emulsions could be formed at a low particle content. The formed Pickering emulsions showed high stability at room temperature without any disturbances, whereas de-emulsification was observed upon improving the pH or adding glucose at a given pH. This is the first report on a responsive Pickering emulsion whose stability can be manipulated by glucose, and this type of fabricated manipulative Pickering emulsions are expected to provide useful guidance in the fields of oil recovery, interfacial reactions, etc.

  9. Effects of postoperative parenteral nutrition with different lipid emulsions in patients undergoing major abdominal surgery

    PubMed Central

    Demirer, Seher; Sapmaz, Ali; Kepenekci, Ilknur; Aydintug, Semih; Balci, Deniz; Sonyurek, Pinar; Kose, Kenan

    2016-01-01

    Purpose This study was designed to investigate the effects of total parenteral nutrition (PN) using different lipid emulsions in patients undergoing major abdominal surgery. Methods Fifty-two patients were randomized to receive soybean oil + medium chain triglycerides (MCT) (group I), soybean oil + olive oil (group II), soybean oil + olive oil + fish oil (group III) as a lipid source. PN was started on postoperative day 1 and patients were maintained on PN for a minimum period of 4 days. Laboratory variables (CRP, prealbumin, transferrin) were measured before surgery and on postoperative days. Results Three treatment groups were included in the study. Patients in group I received long chain triglycerides (LCT) + LCT/MCT emulsion (%75 LCT + %25 LCT/MCT); Patients in group II received olive oil based emulsion (80% olive oil + 20% soybean oil, ClinOleic); Patients in group III received fish oil in addition to olive oil based emulsion (%85 ClinOleic + %15 Omegaven; Fresenius Kabi). The following 14 parameters were assessed: body weight, CRP, prealbumin, transferrin, tumor necrosis factor-α, interleukin-6, total antioxidant status, thiobarbituric acid reactive substances, oxidized low density lipoprotein-2, complete blood cell, international normalized ratio, D-dimer, activated partially thromboplastin time, prothrombin time. All other parameters showed no differences among the groups. Conclusion The results of our trial demonstrate a potential beneficial effect of soybean oil/olive oil based lipid emulsions for use in PN regarding inflammatory response and oxidant capacity in the treatment of patients. PMID:27904853

  10. Intralipid Emulsion Rescue Therapy: Emerging Therapeutic Indications in Medical Practice.

    PubMed

    Muller, Sam H; Diaz, James H; Kaye, Alan David

    2016-01-01

    Intralipid emulsion therapy is well-established for the treatment of local-anesthetic systemic toxicities. In recent years, its role has expanded as an important therapeutic agent in the reversal of other types of drug overdoses, including certain types of antipsychotics, antidepressants, antiarrhythmics, and calcium channel blockers. A literature review identified thirty-one case reports including forty-nine separate drug overdose cases involving ten separate drug classes which were successfully reversed with Intralipid. The present clinical case study describes an elderly unresponsive woman refractory to conventional treatments after ingesting a potentially lethal amount of 5.6 grams of diltiazem in a suicide attempt. After treatment with Intralipid over a twenty-four hour period, the patient's hemodynamic and metabolic derangements were corrected and stabilized completely. Intralipid emulsion rescue therapy provides another potential strategy for the reversal of many drug toxicities, most likely by providing a lipid layer safety net for drug overdose by passive diffusion. Clinicians are urged to embrace an expanded role of Intralipid emulsion rescue therapy, not only for local anesthetic drug toxicities, but also for other lipophilic drug overdoses.

  11. Stabilising emulsion-based colloidal structures with mixed food ingredients.

    PubMed

    Dickinson, Eric

    2013-03-15

    The physical scientist views food as a complex form of soft matter. The complexity has its origin in the numerous ingredients that are typically mixed together and the subtle variations in microstructure and texture induced by thermal and mechanical processing. The colloid science approach to food product formulation is based on the assumption that the major product attributes such as appearance, rheology and physical stability are determined by the spatial distribution and interactions of a small number of generic structural entities (biopolymers, particles, droplets, bubbles, crystals) organised in various kinds of structural arrangements (layers, complexes, aggregates, networks). This review describes some recent advances in this field with reference to three discrete classes of dispersed systems: particle-stabilised emulsions, emulsion gels and aerated emulsions. Particular attention is directed towards explaining the crucial role of the macromolecular ingredients (proteins and polysaccharides) in controlling the formation and stabilisation of the colloidal structures. The ultimate objective of this research is to provide the basic physicochemical insight required for the reliable manufacture of novel structured foods with an appealing taste and texture, whilst incorporating a more healthy set of ingredients than those found in many existing traditional products.

  12. Enhanced fluorescence emitted by microdroplets containing organic dye emulsions

    PubMed Central

    Nastasa, V.; Andrei, I. R.; Staicu, Angela; Pascu, M. L.

    2015-01-01

    In this paper, laser beam resonant interaction with pendant microdroplets that are seeded with a laser dye (Rhodamine 6G (Rh6G)) water solution or oily Vitamin A emulsion with Rhodamine 6G solution in water is investigated through fluorescence spectra analysis. The excitation is made with the second harmonic generated beam emitted by a pulsed Nd:YAG laser system at 532 nm. The pendant microdroplets containing emulsion exhibit an enhanced fluorescence signal. This effect can be explained as being due to the scattering of light by the sub-micrometric drops of oily Vitamin A in emulsion and by the spherical geometry of the pendant droplet. The droplet acts as an optical resonator amplifying the fluorescence signal with the possibility of producing lasing effect. Here, we also investigate how Rhodamine 6G concentration, pumping laser beam energies and number of pumping laser pulses influence the fluorescence behavior. The results can be useful in optical imaging, since they can lead to the use of smaller quantities of fluorescent dyes to obtain results with the same quality. PMID:25784965

  13. Amino acid synthesis in a supercritical carbon dioxide - water system.

    PubMed

    Fujioka, Kouki; Futamura, Yasuhiro; Shiohara, Tomoo; Hoshino, Akiyoshi; Kanaya, Fumihide; Manome, Yoshinobu; Yamamoto, Kenji

    2009-06-15

    Mars is a CO(2)-abundant planet, whereas early Earth is thought to be also CO(2)-abundant. In addition, water was also discovered on Mars in 2008. From the facts and theory, we assumed that soda fountains were present on both planets, and this affected amino acid synthesis. Here, using a supercritical CO(2)/liquid H(2)O (10:1) system which mimicked crust soda fountains, we demonstrate production of amino acids from hydroxylamine (nitrogen source) and keto acids (oxylic acid sources). In this research, several amino acids were detected with an amino acid analyzer. Moreover, alanine polymers were detected with LC-MS. Our research lights up a new pathway in the study of life's origin.

  14. Amino Acid Synthesis in a Supercritical Carbon Dioxide - Water System

    PubMed Central

    Fujioka, Kouki; Futamura, Yasuhiro; Shiohara, Tomoo; Hoshino, Akiyoshi; Kanaya, Fumihide; Manome, Yoshinobu; Yamamoto, Kenji

    2009-01-01

    Mars is a CO2-abundant planet, whereas early Earth is thought to be also CO2-abundant. In addition, water was also discovered on Mars in 2008. From the facts and theory, we assumed that soda fountains were present on both planets, and this affected amino acid synthesis. Here, using a supercritical CO2/liquid H2O (10:1) system which mimicked crust soda fountains, we demonstrate production of amino acids from hydroxylamine (nitrogen source) and keto acids (oxylic acid sources). In this research, several amino acids were detected with an amino acid analyzer. Moreover, alanine polymers were detected with LC-MS. Our research lights up a new pathway in the study of life’s origin. PMID:19582225

  15. Acid-base homeostasis in the human system

    NASA Technical Reports Server (NTRS)

    White, R. J.

    1974-01-01

    Acid-base regulation is a cooperative phenomena in vivo with body fluids, extracellular and intracellular buffers, lungs, and kidneys all playing important roles. The present account is much too brief to be considered a review of present knowledge of these regulatory systems, and should be viewed, instead, as a guide to the elements necessary to construct a simple model of the mutual interactions of the acid-base regulatory systems of the body.

  16. Emulsion properties of pork myofibrillar protein in combination with microbial transglutaminase and calcium alginate under various pH conditions.

    PubMed

    Hong, Geun Pyo; Min, Sang-Gi; Chin, Koo Bok

    2012-01-01

    In this study, the effects of microbial transglutaminase (MTG) and calcium alginate (CA) systems in combination with soybean oil on the emulsion properties of porcine myofibrillar protein (MP) were evaluated under various pH conditions. MTG was shown to improve emulsifying capacity and creaming stability, which increased with increasing pH values up to 6.5. The CA did not influence emulsifying capacity, but it improved the creaming stability of the MP-stabilized emulsions. Both MTG and CA enhanced the rheological properties, but their effects on the physical characteristics of the protein evidenced an opposite trend in relation to pH, i.e., the MTG system improved both the emulsion and gelling properties with increasing pH, whereas the CA system was effective when the pH was lowered. By combining the two MP gelling systems, a stable and pH-insensible emulsion could be produced.

  17. Multiphase flow microfluidics for the production of single or multiple emulsions for drug delivery.

    PubMed

    Zhao, Chun-Xia

    2013-11-01

    Considerable effort has been directed towards developing novel drug delivery systems. Microfluidics, capable of generating monodisperse single and multiple emulsion droplets, executing precise control and operations on these droplets, is a powerful tool for fabricating complex systems (microparticles, microcapsules, microgels) with uniform size, narrow size distribution and desired properties, which have great potential in drug delivery applications. This review presents an overview of the state-of-the-art multiphase flow microfluidics for the production of single emulsions or multiple emulsions for drug delivery. The review starts with a brief introduction of the approaches for making single and multiple emulsions, followed by presentation of some potential drug delivery systems (microparticles, microcapsules and microgels) fabricated in microfluidic devices using single or multiple emulsions as templates. The design principles, manufacturing processes and properties of these drug delivery systems are also discussed and compared. Furthermore, drug encapsulation and drug release (including passive and active controlled release) are provided and compared highlighting some key findings and insights. Finally, site-targeting delivery using multiphase flow microfluidics is also briefly introduced.

  18. Emulsion-directed liquid/liquid interfacial fabrication of lanthanide ion-doped block copolymer composite thin films.

    PubMed

    Hong, Ming; Geng, Yuanyuan; Liu, Mei; Xu, Yuan; Lee, Yong-Ill; Hao, Jingcheng; Liu, Hong-Guo

    2015-01-15

    An emulsion-directed assembly and adsorption approach has been used to fabricate composite films of polystyrene-b-poly(acryl acid)-b-polystyrene (PS-b-PAA-b-PS) and Eu(3+) and La(3+) ions at the planar liquid/liquid interface of the polymer DMF/chloroform (1:1, v/v) mixed solution (lower phase) and aqueous solutions of the corresponding salts (upper phase). The lower phase gradually transformed to a water-in-oil (W/O) emulsion via spontaneous emulsification due to the "ouzo effect". Polymer molecules and the metal ions assembled around emulsion droplets that adsorbed at the planar liquid/liquid interface at last, resulting in formation of composite films. The film morphologies and structures depend on Ln(3+) ions: polymer/Eu(3+) composite films were foam films composed of microcapsules ranging in size from several hundreds of nanometers to micrometers, while polymer/La(3+) composite films were composed of hollow spheres several tens of nanometers in size. Fourier transform infrared (FTIR) spectra revealed that the coordination modes of carboxyl groups to Eu(3+) and La(3+) were bridging bidentate and ionic, respectively, in the two types of composites. These results indicate that stable microcapsules can be fabricated around droplets for polymer/Eu(3+) systems, while microcapsules of polymer/La(3+) are unstable. This leads to different film morphologies and structures. Compositions of these films were characterized using energy-dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). In addition, foam films of polymer/Eu(3+)/2,2'-bipyridine (bpy) were fabricated using this approach, and their photoluminescence properties were investigated.

  19. [Rats hyperuricemia model established by lipid emulsion simulating irregular of diet].

    PubMed

    Ma, Ying-ying; Wu, Yu-lan; Zhu, En-wei; Lv, Gui-yuan; Chen, Su-hong; Pang, Min-xi

    2015-05-01

    Due to the irregular of diet and overfeeding greasy and surfeit flavor closely associated with hyperuricemia disease, the lipid emulsion containing high cholesterol was used to model. To obtain a more stable and sustained animal model for the efficacy evaluation of traditional Chinese herbs, we observed the influence on the serum uric acid of rat induced by the lipid emulsion compared with high purine diet. 36 SD male rats were randomized to the normal control group, high purine diet group and lipid emulsion group respectively. The general behavior, body weight and daily food intake of rats were observed. The orbital blood was taken to separate into the serum and 24 hours urine was collected. The serum indexes such as UA, BUN, Cr, ALT, AST, TC, TG, LDL-c were determined every 2 weeks, and XOD, ADA enzyme activity were determined at the 4th week. The urine indexes such as UA, Cr and Cua/Ccr were determined at the 4th week. After stopping modeling, the serum UA were determined two weeks and four weeks later respectively. At the 2nd week, the body weight and daily food intake of rats in the lipid emulsion group reduced significantly, and the level of serum UA, BUN, Cr, TC, LDL-c, ATL, AST raised significantly meanwhile TG reduced. At the 4th week, the serum UA in high purine diet group did not raise, and the serum XOD raised obviously while ADA did not; the serum UA in lipid emulsion group was higher significantly, and the serum XOD and ADA raised while Cua/Ccr reduced obviously. At the 6th weeks, the serum UA in both the high purine diet group and lipid emulsion group raised obviously. After stopping modeling, the serum UA in lipid emulsion group still maintained a high level at the 2nd week and back to the normal level at the 4th week. Compared with high purine diet, the hyperuricemia model induced by lipid emulsion forms earlierand more stable. It maybe has great value to study the pharmacodynamics of traditional Chinese medicine treatment to hyperuricemia disease

  20. D-Amino Acids in the Nervous and Endocrine Systems

    PubMed Central

    Kiriyama, Yoshimitsu

    2016-01-01

    Amino acids are important components for peptides and proteins and act as signal transmitters. Only L-amino acids have been considered necessary in mammals, including humans. However, diverse D-amino acids, such as D-serine, D-aspartate, D-alanine, and D-cysteine, are found in mammals. Physiological roles of these D-amino acids not only in the nervous system but also in the endocrine system are being gradually revealed. N-Methyl-D-aspartate (NMDA) receptors are associated with learning and memory. D-Serine, D-aspartate, and D-alanine can all bind to NMDA receptors. H2S generated from D-cysteine reduces disulfide bonds in receptors and potentiates their activity. Aberrant receptor activity is related to diseases of the central nervous system (CNS), such as Alzheimer's disease, amyotrophic lateral sclerosis, and schizophrenia. Furthermore, D-amino acids are detected in parts of the endocrine system, such as the pineal gland, hypothalamus, pituitary gland, pancreas, adrenal gland, and testis. D-Aspartate is being investigated for the regulation of hormone release from various endocrine organs. Here we focused on recent findings regarding the synthesis and physiological functions of D-amino acids in the nervous and endocrine systems. PMID:28053803

  1. The effect of butter grains on physical properties of butter-like emulsions.

    PubMed

    Rønholt, Stine; Buldo, Patrizia; Mortensen, Kell; Andersen, Ulf; Knudsen, Jes C; Wiking, Lars

    2014-01-01

    Milk fat exists as globules in its natural state in milk. The potential of using globular fat to modulate the rheological properties and crystallization behavior in butter-like emulsions was studied in the present work. We conducted a comparative study of butter-like emulsions, with a fat phase consisting of 0, 10, 25, 50, or 100% anhydrous milk fat (AMF), the remaining fat being butter grains, and all samples containing 20% water, to obtain systematic variation in the ratio of globular fat. All emulsions were studied over 4wk of storage at 5°C. By combining small and large deformation rheology, we conducted a detailed characterization of the rheological behavior of butter-like emulsions. We applied differential scanning calorimetry to monitor thermal behavior, confocal laser scanning microscopy for microstructural analysis, and low-field pulsed nuclear magnetic resonance spectrometry to measure solid fat content. By combining these techniques, we determined that increasing the fraction of globular fat (by mixing with butter grains) decreases the hardness of butter-like emulsions up to an order of magnitude at d 1. However, no difference was observed in thermal behavior as a function of butter grain content, as all emulsions containing butter grains revealed 2 endothermal peaks corresponding to the high (32.7°C ± 0.6) and medium (14.6°C ± 0.1) melting fractions of fatty acids. In terms of microstructure, decreasing the amount of butter grains in the emulsions resulted in formation of a denser fat crystal network, corresponding to increased hardness. Moreover, microstructural analysis revealed that the presence of butter grains resulted in faster formation of a continuous fat crystal network compared with the 100% AMF sample, which was dominated by crystal clusters surrounded by liquid oil. During storage, hardness remained stable and no changes in thermal behavior were observed, despite an increase in solid fat content of up to 5%. After 28d of storage, we

  2. Catalytic Emulsion Based on Janus Nanosheets for Ultra-Deep Desulfurization.

    PubMed

    Xia, Lixin; Zhang, Hairan; Wei, Zhichao; Jiang, Yi; Zhang, Ling; Zhao, Jie; Zhang, Junhui; Dong, Li; Li, Erni; Ruhlmann, Laurent; Zhang, Qian

    2017-02-03

    Catalytic Janus nanosheets were synthesized by using an anion-exchange reaction between heteropolyacids (HPAs) and the modified ionic-liquid (IL) moieties of Janus nanosheets. Their morphology and surface properties were characterized by using SEM, energy-dispersive spectroscopy (EDS), FTIR spectroscopy, and X-ray photoelectron spectroscopy (XPS) studies. Because of their inherent Janus structure, the nanosheets exhibited good amphipathic character with ILs and oil to form a stable ILs-in-oil emulsion. Therefore, these Janus nanosheets can be used as both emulsifiers and catalysts to perform emulsive desulfurization. During this process, sulfur-containing compounds at the interface could be easily oxidized and efficiently removed from a model oil. Application of this Janus emulsion brings an efficient, useful, and green procedure to the desulfurization process. Compared with the desulfurization catalyzed by using HPAs in a conventional two-phase system, the sulfur removal of dibenzothiophene (DBT) achieved in a Janus emulsion system was improved from 68 to 97 % within 1.5 h. Moreover, this emulsion system could be demulsified easily by simple centrifugation to recover both the nanosheets and the ILs. Owing to the good structural stability of the Janus nanosheets, the sulfur removal efficiency of DBT could still reach 99.9 % after the catalytic nanosheets had been recycled at least six times.

  3. Utilization of interfacial engineering to improve physicochemical stability of β-carotene emulsions: Multilayer coatings formed using protein and protein-polyphenol conjugates.

    PubMed

    Liu, Fuguo; Wang, Di; Sun, Cuixia; McClements, David Julian; Gao, Yanxiang

    2016-08-15

    The impact of lactoferrin (LF)-chlorogenic acid (CA) and (-)-Epigallocatechin-3-gallate (EGCG) conjugates on the physicochemical properties of β-carotene emulsions was investigated. Formation of lactoferrin-polyphenol conjugates, which was confirmed by SDS-PAGE, caused changes in the structure and nature of lactoferrin. Based on layer-by-layer electrostatic deposition, β-carotene bilayer emulsions were prepared by lactoferrin and lactoferrin-polyphenol conjugates at pH 7.0. The physicochemical properties of primary and secondary emulsions were evaluated and the results suggested that LF-polyphenol conjugates-stabilized primary and secondary emulsions exhibited better emulsifying properties and improved physical stability of β-carotene bilayer emulsions under freeze-thaw, ionic strength and thermal treatments. In addition, the lactoferrin-polyphenol conjugates could effectively enhance chemical stability of β-carotene in oil-in-water emulsions against heat treatment and ultraviolet light exposure, and the least degradation of β-carotene occurred in LF-EGCG conjugate-stabilized primary emulsion. The interfacial engineering technology utilized in this study may lead to the formation of emulsions with improved physicochemical and functional performance.

  4. Study of intragastric structuring ability of sodium alginate based o/w emulsions under in vitro physiological pre-absorptive digestion conditions.

    PubMed

    Soukoulis, Christos; Fisk, Ian D; Bohn, Torsten; Hoffmann, Lucien

    2016-04-20

    In the present work, the intragastric structuring ability of o/w emulsions either stabilised (1-4%, w/w of sodium alginate (SA)) or structured with sheared ionic gel (1-3%, w/w of SA crosslinked with Ca(2+)) in the absence (saliva and gastric phases constituted of deionised water) or presence of in vitro pre-absorptive conditions (physiological simulated saliva and gastric fluids) was investigated. Visualisation of the morphological aspects of the gastric chymes, in the absence of multivalent counterions, demonstrated that SA stabilised systems underwent a remarkable swelling in the pH range of 2-3, whilst at the same pH range, ionic SA gel structured systems maintained their major structure configuration. When the aforementioned systems were exposed to physiological intragastric fluids, a reduction of the length and the hydrodynamic volume of the alginate fibres was detected regardless the structuring approach. On their exposure to physiological intragastric conditions (pH=2), SA stabilised emulsions underwent sol-gel transition achieving a ca. 3- to 4-order increase of storage modulus (at 1Hz). In the case of ionic sheared gel structured emulsions, exposure to physiological intragastric fluids resulted in a 10-fold reduction ability of their acid structuring ability, most likely due to the dialysis of egg-box dimer conformations by monovalent cations and protons and the sterical hindering of hydrogen bonding of MM and GG sequences under acidic conditions. Using of non-physiological simulated intragastric fluids was associated with overestimated structuring performance of SA regardless its physical state.

  5. Leaching of plasticizers from polyvinylchloride perfusion lines by different lipid emulsions for premature infants under clinical conditions.

    PubMed

    Faessler, David; McCombie, Gregor; Biedermann, Maurus; Felder, Florian; Subotic, Ulrike

    2017-03-30

    Plasticizers migrate from polyvinylchloride (PVC) infusion systems into lipid emulsions. The aim of this study was to investigate the leaching of different plasticizers from PVC perfusion lines by a selection of lipid emulsions under clinical conditions. Seven PVC perfusion lines with an equal length of 150cm and three internal diameters were perfused with three lipid emulsions: Intralipid(®) 20%, ClinOleic(®) 20% and SMOFlipid(®) 20%, mimicking clinical conditions. The concentrations of the plasticizers were measured directly in the emulsions by gas chromatography - mass spectrometry. Of the four plasticizers examined in this study, di (2-ethylhexyl) phthalate (DEHP) leached the most and was found, on average, at 46.5μg/ml in the emulsions - around one order of magnitude higher than the other plasticizers. This study demonstrates that the leaching of DEHP by lipid emulsions in conditions of total parenteral nutrition is many times higher than should be accepted and higher when compared to the other plasticizers. There was no significant difference in leaching of plasticizers in relation to the type of lipid emulsion. The influence of tube diameter on the leaching rate of plasticizers should be taken into account especially in particular exposed patients.

  6. Expert systems help design cementing and acidizing jobs

    SciTech Connect

    Onan, D.D.; Kulakofsky, D.; Van Domelen, M.S.; Ford, W.G.F. )

    1993-04-19

    Knowledge-based expert information systems can help train less-experienced designers and orient seasoned designers at new locations. These systems are playing an increased role in completion and production operations. Expert systems help: design treatments based on an accumulation of knowledge from experts; provide technical information and guidelines on the proper use of additives; and serve as a training tool for less-experienced personnel. The paper describes expert systems design; practical applications; and details about a cement job and acidizing.

  7. Inhibition of natural killer cell activity by eicosapentaenoic acid in vivo and in vitro

    SciTech Connect

    Yamashita, N.; Sugiyama, E.; Hamazaki, T.; Yano, S.

    1988-01-15

    To examine the effects of in vivo eicosapentaenoic acid (EPA) on natural killer (NK) cell activity, C3H/He mice each received a single intraperitoneal bolus of an emulsion of trieicosapentaenoyl-glycerol (EPA-TG). Spleen cells were tested for NK activity using /sup 51/Chromium-release assays against YAC-1 target cells. Forty eight hours after injection, NK activity was inhibited in a dose-dependent manner. EPA-TG emulsion also inhibited the NK activity of NK-enriched effector cells. Decreased cytotoxicity was first noted 24 hr after injection; it resumed the baseline by 7 days. The addition of EPA-TG emulsion to a cytotoxicity assay system resulted in moderate depression of NK activity. These results demonstrate that EPA has significant immunomodulatory effects on NK activity.

  8. High pressure-resistant nonincendive emulsion explosive

    DOEpatents

    Ruhe, Thomas C.; Rao, Pilaka P.

    1994-01-01

    An improved emulsion explosive composition including hollow microspheres/bulking agents having high density and high strength. The hollow microspheres/bulking agents have true particle densities of about 0.2 grams per cubic centimeter or greater and include glass, siliceous, ceramic and synthetic resin microspheres, expanded minerals, and mixtures thereof. The preferred weight percentage of hollow microspheres/bulking agents in the composition ranges from 3.0 to 10.0 A chlorinated paraffin oil, also present in the improved emulsion explosive composition, imparts a higher film strength to the oil phase in the emulsion. The emulsion is rendered nonincendive by the production of sodium chloride in situ via the decomposition of sodium nitrate, a chlorinated paraffin oil, and sodium perchlorate. The air-gap sensitivity is improved by the in situ formation of monomethylamine perchlorate from dissolved monomethylamine nitrate and sodium perchlorate. The emulsion explosive composition can withstand static pressures to 139 bars and dynamic pressure loads on the order of 567 bars.

  9. A new drug nanocrystal self-stabilized Pickering emulsion for oral delivery of silybin.

    PubMed

    Yi, Tao; Liu, Chuan; Zhang, Jiao; Wang, Fan; Wang, Jirui; Zhang, Jifen

    2017-01-01

    A new silybin nanocrystal self-stabilized Pickering emulsion (SN-SSPE) has been developed using a high pressure homogenization method to improve the oral bioavailability of silybin. Influences of homogenization pressure and drug content on the formation of SN-SSPE were studied. The morphology, structure and size of Pickering emulsion droplets were characterized using a scanning electron micrograph, confocal laser scanning microscopy and atomic force microscopy. The stability, in vitro release and in vivo oral bioavailability of SN-SSPE were investigated. Results indicated that the particle size of silybin nanocrystals (SN-NC) decreased when homogenization pressure increased until 100MPa. When the content of silybin reached 300mg or above, a stable Pickering emulsion of silybin could be formed by sufficient SN-NC covering surfaces of oil droplets completely and thus self-stabilizing the Pickering emulsion. The emulsion droplet of SN-SSPE with the size of 27.3±3.1μm showed a core-shell structure consisting of a core of oil and a shell of SN-NC. SN-SSPE has shown high stability over 40days. The in vitro release rate of SN-SSPE was faster than silybin coarse powder and similar to silybin nanocrystalline suspension (SN-NCS). The peak concentration of silybin of SN-SSPE following intragastric administration in rats was increased by 2.5-fold and 3.6-fold compared with SN-NCS and silybin coarse powder, respectively. The AUC of SN-SSPE was increased by 1.6-fold and 4.0-fold compared with SN-NCS and silybin coarse powder, respectively. All these results showed that the Pickering emulsion of silybin could be stabilized by nanocrystals of silybin itself and increased the oral bioavailability of silybin. The drug nanocrystalline self-stabilized Pickering emulsion was a promising oral drug delivery system for poorly soluble drugs.

  10. A model for the prediction of droplet size in Pickering emulsions stabilized by oppositely charged particles.

    PubMed

    Nallamilli, Trivikram; Mani, Ethayaraja; Basavaraj, Madivala G

    2014-08-12

    Colloidal particles irreversibly adsorb at fluid-fluid interfaces stabilizing what are commonly called "Pickering" emulsions and foams. A simple geometrical model, the limited coalescence model, was earlier proposed to estimate droplet sizes in emulsions. This model assumes that all of the particles are effective in stabilization. The model predicts that the average emulsion drop size scales inversely with the total number of particles, confirmed qualitatively with experimental data on Pickering emulsions. In recent years, there has been an increasing interest in synthesizing emulsions with oppositely charged particles (OCPs). In our experimental study, we observed that the drop size varies nonmonotonically with the number ratio of oppositely charged colloids, even when a fixed total number concentration of colloids is used, showing a minimum. We develop a mathematical model to predict this dependence of drop size on number ratio in such a mixed particle system. The proposed model is based on the hypothesis that oppositely charged colloids form stable clusters due to the strong electrostatic attraction between them and that these clusters are the effective stabilizing agents. The proposed model is a two-parameter model, parameters being the ratio of effective charge of OCPs (denoted as k) and the size of the aggregate containing X particles formed due to aggregation of OCPs. Because the size of aggregates formed during emulsification is not directly measurable, we use suitable values of parameters k and X to best match the experimental observations. The model predictions are in qualitative agreement with experimentally observed nonmonotonic variation of droplet sizes. Using experiments and theory, we present a physical insight into the formation of OCP stabilized Pickering emulsions. Our model upgrades the existing Wiley's limited coalescence model as applied to emulsions containing a binary mixture of oppositely charged particles.

  11. Interparticle interactions in concentrate water-oil emulsions.

    PubMed

    Mishchuk, N A; Sanfeld, A; Steinchen, A

    2004-12-31

    The present investigation is based on the description of electrostatic interaction in concentrated disperse systems proposed 45 years ago by Albers and Overbeek. Starting from their model, we developed a stability theory of concentrated Brownian W/O emulsions in which nondeformed droplets undergo electrostatic and Van der Waals interactions. While the droplets in dilute emulsion may be described by pair interaction, in dense emulsions, every droplet is closely surrounded by other droplets, and when two of them come together, not only the energy of their pair interaction, but also their interaction with surrounding droplets change. Unlike in dilute emulsion, for which the reference energy of the pair is the energy at infinity (taken equal to zero), in concentrate emulsion, the reference energy is not zero but is the energy of interaction with averaged ensemble of nearest droplets. The larger the volume fraction, the higher the reference energy and, thus, the lower the energy barrier between two coagulating droplets, which enhances the coagulation. In dense packing of drops, the energy of interaction and the reference energy coincide, therefore, the height of energy barrier vanishes. In contrast with dense emulsion, at medium volume fraction, when two coagulating droplets interact only with a few nearest neighbors, our analysis shows that the energy barrier may also increase, which extends thus the domain of stability. Because in W/O emulsion, the thickness of the electric double layer is of the same order or larger than the size of droplets, the electrostatic energy was calculated with a correction factor beta that accounts for the deviation of double layers from sphericity. A more complete van der Waals interaction with account of screening of interaction by electrolyte has been used. Both factors promote the decrease of energy barrier between coagulating droplets and enhance the coagulation. Our model introduces two critical volume fractions. The first one, phi(c1

  12. Microbial Nucleic Acid Sensing in Oral and Systemic Diseases.

    PubMed

    Crump, K E; Sahingur, S E

    2016-01-01

    One challenge in studying chronic infectious and inflammatory disorders is understanding how host pattern recognition receptors (PRRs), specifically toll-like receptors (TLRs), sense and respond to pathogen- or damage-associated molecular patterns, their communication with each other and different components of the immune system, and their role in propagating inflammatory stages of disease. The discovery of innate immune activation through nucleic acid recognition by intracellular PRRs such as endosomal TLRs (TLR3, TLR7, TLR8, and TLR9) and cytoplasmic proteins (absent in melanoma 2 and DNA-dependent activator of interferon regulatory factor) opened a new paradigm: Nucleic acid sensing is now implicated in multiple immune and inflammatory conditions (e.g., atherosclerosis, cancer), viral (e.g., human papillomavirus, herpes virus) and bacterial (e.g., Helicobacter pylori, pneumonia) diseases, and autoimmune disorders (e.g., systemic lupus erythematosus, rheumatoid arthritis). Clinical investigations reveal the overexpression of specific nucleic acid sensors in diseased tissues. In vivo animal models show enhanced disease progression associated with receptor activation. The involvement of nucleic acid sensors in various systemic conditions is further supported by studies reporting receptor knockout mice being either protected from or prone to disease. TLR9-mediated inflammation is also implicated in periodontal diseases. Considering that persistent inflammation in the oral cavity is associated with systemic diseases and that oral microbial DNA is isolated at distal sites, nucleic acid sensing may potentially be a link between oral and systemic diseases. In this review, we discuss recent advances in how intracellular PRRs respond to microbial nucleic acids and emerging views on the role of nucleic acid sensors in various systemic diseases. We also highlight new information on the role of intracellular PRRs in the pathogenesis of oral diseases including periodontitis

  13. Emulsions stability, from dilute to dense emulsions -- role of drops deformation.

    PubMed

    Sanfeld, Albert; Steinchen, Annie

    2008-07-01

    , considering that in most publications on emulsions foams and colloidal systems, much attention is paid on the role of the drainage in the stability process, we devote the last section to the drainage between flattened drops. We first describe briefly Taylor's approach and extend Reynolds revisited formulae taking into account the viscous friction, the disjoining pressure, the film elasticity and the wetting angle weighting the capillary pressure through the characteristic length. Our calculated values are compared to some experimental data. In conclusion to make this long paper as useful as possible for research purposes, we have the hope that our understanding of emulsion stability is not only based on knowledge of numerous theoretical and experimental works sometimes controversial given in a critical way but that it gives a new approach based on an interpretation of the drop deformation in terms of a characteristic length linked to a deformation number analogous to a Bond number.

  14. 21 CFR 862.1320 - Gastric acidity test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Gastric acidity test system. 862.1320 Section 862.1320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  15. 21 CFR 862.1295 - Folic acid test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Folic acid test system. 862.1295 Section 862.1295 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  16. 21 CFR 862.1295 - Folic acid test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Folic acid test system. 862.1295 Section 862.1295 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  17. 21 CFR 862.1290 - Fatty acids test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Fatty acids test system. 862.1290 Section 862.1290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  18. 21 CFR 862.1290 - Fatty acids test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Fatty acids test system. 862.1290 Section 862.1290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  19. 21 CFR 862.1295 - Folic acid test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Folic acid test system. 862.1295 Section 862.1295 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  20. 21 CFR 862.1095 - Ascorbic acid test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ascorbic acid test system. 862.1095 Section 862.1095 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  1. 21 CFR 862.1290 - Fatty acids test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Fatty acids test system. 862.1290 Section 862.1290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  2. 21 CFR 862.1095 - Ascorbic acid test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ascorbic acid test system. 862.1095 Section 862.1095 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  3. 21 CFR 862.1095 - Ascorbic acid test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ascorbic acid test system. 862.1095 Section 862.1095 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  4. 21 CFR 862.1320 - Gastric acidity test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Gastric acidity test system. 862.1320 Section 862.1320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  5. 21 CFR 862.1320 - Gastric acidity test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Gastric acidity test system. 862.1320 Section 862.1320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  6. 21 CFR 862.1320 - Gastric acidity test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Gastric acidity test system. 862.1320 Section 862.1320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  7. 21 CFR 862.1320 - Gastric acidity test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gastric acidity test system. 862.1320 Section 862.1320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  8. 21 CFR 862.1655 - Pyruvic acid test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Pyruvic acid test system. 862.1655 Section 862.1655 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  9. 21 CFR 862.1655 - Pyruvic acid test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Pyruvic acid test system. 862.1655 Section 862.1655 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  10. Double hypernuclei experiment with hybrid emulsion method (J-PARC E07)

    NASA Astrophysics Data System (ADS)

    Ekawa, Hiroyuki; J-APRC E07 Collaboration

    2014-09-01

    Double hypernuclei are important probes to study the system with strangeness -2. In order to search for double hypernuclei, an upgrade experiment is planned at J-PARC K1.8 beam line. In the experiment, the KURAMA spectrometer system will detect Ξ- production in the (K- ,K+) reaction on a diamond target. SSDs located the upstream and the downstream of emulsion plates will record Ξ- tracks which flight toward emulsion plates precisely. Tracks in SSDs and emulsion will be automatically connected by a hybrid method. Discoveries of more than 10 new double hypernuclear species are expected, which enable us to discuss binding energy in terms of mass number dependence. On the other hand, we will also observe X rays from Ξ- atoms with a Germanium detector array installed close to the emulsion by tagging Ξ-stopped events. This will be the first measurement in the world and give information on the Ξ-potential shape at the nuclear surface region. Emulsion production has been completely done and a test experiment for some detectors of KURAMA spectrometer was carried out. In this talk, physics motivation and current status of the J-PARC E07 experiment will be reported.

  11. A disposable emulsion droplet generation lab chips driven by vacuum module for manipulation of blood cells.

    PubMed

    Chia-Hung Lee; Chien-Chong Hong

    2015-08-01

    This paper presents a novel disposable emulsion droplet generation lab chip driven by vacuum module for monodisperse emulsions generation and blood cell encapsulation. Emulsion droplet is a powerful tool in miniaturized analysis systems for high throughput processing. It shows great potential in chemical and biological reactions like speeding up the reaction and reducing the cost of reagents. Most research groups use syringe pumps providing positive pressure to drive the fluids. However, the long tubing connection and high cost make the microfluidic systems complicate and unsuitable for lab-on-a-chip (LOC) device. In this paper, our emulsion droplet generation lab chip with disposable vacuum module, made of shape memory polymer, provides a negative pressure to drive the fluids. This lab chip could achieve creating monodisperse emulsion droplets by manipulating two-phase microfluidic within 1 set of vacuum module and mini-heater. In the meantime, the waste is gathered into the cavity of vacuum module. This makes this lab chip safe while using biological samples. The vacuum module shows the advantages of compact, simple structure, and east-to-attach with the microfluidic device and great performance in the experiments.

  12. Method development for Cd and Hg determination in biodiesel by electrothermal atomic absorption spectrometry with emulsion sample introduction.

    PubMed

    Aranda, Pedro R; Gásquez, José A; Olsina, Roberto A; Martinez, Luis D; Gil, Raúl A

    2012-11-15

    A novel method for analysis of biodiesel by electrothermal atomic absorption spectrometry is described. This analytical strategy involves sample preparation as emulsions for routine and reliable determination of Cd and Hg. Several experimental conditions were investigated, including emulsion stability and composition, furnace temperature program and matrix modification. Different calibration strategies were also evaluated, being the analyte addition method preferred both for Cd and Hg. The accuracy was verified through comparison with an acid digestion in a microwave closed system. The injection repeatability was evaluated as the average relative standard deviation (R.S.D %) for five successive firings and was better than 4.4% for Cd and 5.4% Hg respectively. The detection limits, evaluated by the 3σ concept of calculation (n=10), were of 10.2 μg kg(-1) (0.9 μg L(-1)) for Hg and 0.3 μg kg(-1) (0.04 μg L(-1)) for Cd. This method was successfully applied to the determination of Cd and Hg in biodiesel samples obtained from local vendors.

  13. Superabsorbent, High Porosity, PAMPS-Based Hydrogels through Emulsion Templating.

    PubMed

    Kovačič, Sebastijan; Silverstein, Michael S

    2016-09-26

    Swell! Superabsorbent, mechanically robust, high-porosity hydrogels based on poly(2-acrylamido-2-methyl-1-propanesulfonic acid) have been successfully synthesized by templating within high internal phase emulsions (HIPEs). These hydrogel polyHIPEs (HG-PHs) exhibit unusually high uptakes of water and of artificial urine through structure- and crosslinking-dependent hydrogel-swelling-driven void expansion. An HG-PH with 3.1 mmol g(-1) of highly accessible sulfonic acid groups exhibits a 7 meq NaOH ion exchange capacity per gram polymer and rapid dye absorption. The highly swollen HG-PHs do not fail at compressive strains of up to 60%, they retain water and recover their shapes upon the removal of stress. Unusually, the dry hydrogels have relatively high compressive moduli and achieve relatively high stresses at 70% strain.

  14. Physico-chemical characteristics of oil-in-water emulsions based on whey protein-phospholipid mixtures.

    PubMed

    Sünder, A; Scherze, I; Muschiolik, G

    2001-07-01

    Emulsions prepared with whey proteins, phospholipids and 10% of vegetable oil were used for a model typifying dressings, coffee whitener and balanced diets. For the present study, two whey proteins (partial heat-denatured whey protein concentrate (WPC) and undenatured whey protein isolate (WPI)) in combination with different phospholipids (hydrolysed and unmodified deoiled lecithin) were chosen to investigate the interactions between proteins, phospholipids and salt (sodium chloride) in such emulsion systems. Oil-in-water (o/w) emulsions (10 wt.% sunflower oil) containing various concentrations of commercial whey proteins (1-2%), phospholipids (0.39-0.78%) and salt (0.5-1.5%) were prepared using a laboratory high pressure homogeniser under various preparation conditions. Each emulsion was characterised by droplet size, creaming rate, flow behaviour and protein load. The dynamic surface activity of the whey proteins and lecithins at the oil-water interface was determined using the drop volume method. The properties of emulsions were significantly influenced by the content of whey protein. Higher protein levels improved the emulsion behaviour (smaller oil droplets and increased stability) independent of the protein or lecithin samples used. An increase of the protein content resulted in a lower tendency for oil droplet aggregation of emulsions with WPC to occur and emulsions tending towards a Newtonian flow behaviour. The emulsification temperature was especially important using the partial heat-denatured WPC in combination with the deoiled lecithin. A higher emulsification temperature (60 degrees C) promoted oil droplet aggregation, as well as an increased emulsion consistency. Emulsions with the WPC were significantly influenced by the NaCl content, as well as the protein-salt ratio. Increasing the NaCl content led to an increase of the droplet size, higher oil droplet aggregation, as well as to a higher creaming rate of the emulsions. An increase of the lecithin

  15. Competitive displacement of sodium caseinate by low-molecular-weight emulsifiers and the effects on emulsion texture and rheology.

    PubMed

    Munk, M B; Larsen, F H; van den Berg, F W J; Knudsen, J C; Andersen, M L

    2014-07-29

    Low-molecular-weight (LMW) emulsifiers are used to promote controlled destabilization in many dairy-type emulsions in order to obtain stable foams in whippable products. The relation between fat globule aggregation induced by three LMW emulsifiers, lactic acid ester of monoglyceride (LACTEM), saturated monoglyceride (GMS), and unsaturated monoglyceride (GMU) and their effect on interfacial protein displacement was investigated. It was found that protein displacement by LMW emulsifiers was not necessary for fat globule aggregation in emulsions, and conversely fat globule aggregation was not necessarily accompanied by protein displacement. The three LMW emulsifiers had very different effects on emulsions. LACTEM induced shear instability of emulsions, which was accompanied by protein displacement. High stability was characteristic for emulsions with GMS where protein was displaced from the interface. Emulsions containing GMU were semisolid, but only low concentrations of protein were detected in the separated serum phase. The effects of LACTEM, GMS, and GMU may be explained by three different mechanisms involving formation of interfacial α-gel, pickering stabilization and increased exposure of bound casein to the water phase. The latter may facilitate partial coalescence. Stabilizing hydrocolloids did not have any effect on the LMW emulsifiers' ability to induce protein displacement.

  16. Jasmonic acid and salicylic acid activate a common defense system in rice

    PubMed Central

    Tamaoki, Daisuke; Seo, Shigemi; Yamada, Shoko; Kano, Akihito; Miyamoto, Ayumi; Shishido, Hodaka; Miyoshi, Seika; Taniguchi, Shiduku; Akimitsu, Kazuya; Gomi, Kenji

    2013-01-01

    Jasmonic acid (JA) and salicylic acid (SA) play important roles in plant defense systems. JA and SA signaling pathways interact antagonistically in dicotyledonous plants, but, the status of crosstalk between JA and SA signaling is unknown in monocots. Our rice microarray analysis showed that more than half of the genes upregulated by the SA analog BTH are also upregulated by JA, suggesting that a major portion of the SA-upregulated genes are regulated by JA-dependent signaling in rice. A common defense system that is activated by both JA and SA is thus proposed which plays an important role in pathogen defense responses in rice. PMID:23518581

  17. Influence of polysaccharides on the rheology and stabilization of α-pinene emulsions.

    PubMed

    García, Ma Carmen; Alfaro, Ma Carmen; Calero, Nuria; Muñoz, José

    2014-05-25

    This work focuses on the need to include polysaccharides in a slightly concentrated O(α-pinene)/W emulsion, formulated with amphiphilic copolymers as emulsifiers. Rheology, laser diffraction and multiple light scattering were the main techniques used to assess the performance of gellan gum, xanthan gum and a mixture of both hydrocolloids as stabilizers. Small amplitude oscillatory shear results were consistent with the existence of three distinct microstructures and relaxation mechanisms, which depended on the hydrocolloid system used. The mechanical spectrum of the emulsion containing both polysaccharides signalled the occurrence of thermodynamic incompatibility between the two. Flow curves fitted to the Carreau-Yasuda model demonstrated a negative synergistic effect between gellan and xanthan gums. The droplet size distribution was similar for these systems, which highlighted the importance of the continuous phase for emulsion stability. Multiple light scattering illustrated that creaming was practically eliminated by the incorporation of polysaccharides, coalescence being the main destabilization mechanism.

  18. Intravenous lipid emulsions combine extracorporeal blood purification: a novel therapeutic strategy for severe organophosphate poisoning.

    PubMed

    Zhou, Yaguang; Zhan, Chengye; Li, Yongsheng; Zhong, Qiang; Pan, Hao; Yang, Guangtian

    2010-02-01

    Organophosphorus (OP) pesticide self-poisoning is a major clinical problem in rural Asia and it results in the death of 200,000 people every year. At present, it is lack of effective methods to treat severe organophosphate poisoning. The high mortality rate lies on the amount of toxic absorption. Intravenous lipid emulsions can be used as an antidote in fat-soluble drug poisoning. The detoxification mechanism of intravenous lipid emulsions is "lipid sink", which lipid emulsions can dissolve the fat-soluble drugs and separate poison away from the sites of toxicity. Most of organophosphorus pesticides are highly fat-soluble. So, intravenous lipid emulsions have the potentially clinical applications in treatment of OP poisoning. Extracorporeal blood purification especially charcoal hemoperfusion is an efficient way to eliminate the poison contents from the blood. We hypothesize that the combination of intravenous lipid emulsions and charcoal hemoperfusion can be used to cure severe organophosphate poisoning. This novel protocol of therapy comprises two steps: one is obtained intravenous access to infuse lipid emulsions as soon as possible; another is that charcoal hemoperfusion will be used to clear the OP substances before the distribution of OP compounds in tissue is not complete. The advantages of this strategy lie in three points. Firstly, it will alleviate the toxic effect of OP pesticide in the patients by isolation and removal the toxic contents. Secondly, the dosage of antidotes can be reduced and its side-effects will be eased. Thirdly, a large bolus of fatty acids provide energy substrate for the patients who are nil by mouth. We consider that it would become a feasible, safe and efficient detoxification intervention in the alleviation of severe organophosphate poisoning, which would also improve the outcome of the patients.

  19. Phase diagram of a system of adipic, glutaric, and sebacic acids

    NASA Astrophysics Data System (ADS)

    Kolyado, A. V.; Alenova, S. M.; Garkushin, I. K.

    2016-06-01

    Adipic acid-glutaric acid, glutaric acid-sebacic acid, and adipic acid-sebacic acid binary systems are studied, along with an adipic acid-glutaric acid-sebacic acid ternary system. It is shown all of these systems are eutectic. Phase equilibria for the diagram elements of the binary systems and the ternary system are described. It is concluded that the above low-melting compounds can be recommended for use as working bodies in heat accumulators, and for preparing electrolytes used in the thin-layer anodic oxidation of aluminum alloys.

  20. Gas dilution system results and application to acid rain utilities

    SciTech Connect

    Jolley-Souders, K.; Geib, R.; Dunn, C.

    1997-12-31

    In 1997, the United States EPA will remove restrictions preventing acid rain utilities from using gas dilution systems for calibration or linearity studies for continuous emissions monitoring, Test Method 205 in 40CFR51 requires that a gas dilution system must produce calibration gases whose measured values are within {+-}2% of predicted values. This paper presents the evaluation of the Environics/CalMat 2020 Dilution System for use in calibration studies. Internal studies show that concentrations generated by this unit are within {+-}0.5% of predicted values. Studies are being conducted by several acid rain utilities to evaluate the Environics/CalMat system using single minor component calibration standards. In addition, an internally generated study is being performed to demonstrate the system`s accuracy using a multi-component gas mixture. Data from these tests will be presented in the final version of the paper.

  1. 300 Area waste acid treatment system closure plan

    SciTech Connect

    LUKE, S.N.

    1999-05-17

    The Hanford Facility Dangerous Waste Permit Application is considered to be a single application organized into a General Information Portion (document number DOERL-91-28) and a Unit-Specific Portion. The scope of the Unit-Specific Portion includes closure plan documentation submitted for individual, treatment, storage, and/or disposal units undergoing closure, such as the 300 Area Waste Acid Treatment System. Documentation contained in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units (e.g., the glossary provided in the General Information Portion). Whenever appropriate, 300 Area Waste Acid Treatment System documentation makes cross-reference to the General Information Portion, rather than duplicating text. This 300 Area Waste Acid Treatment System Closure Plan (Revision 2) includes a Hanford Facility Dangerous Waste Permit Application, Part A, Form 3. Information provided in this closure plan is current as of April 1999.

  2. Status of commercial phosphoric acid fuel cell system development

    NASA Technical Reports Server (NTRS)

    Warshay, M.; Prokopius, P. R.; Simons, S. N.; King, R. B.

    1981-01-01

    A review of the current commercial phosphoric acid fuel cell system development efforts is presented. In both the electric utility and on-site integrated energy system applications, reducing cost and increasing reliability are important. The barrier to the attainment of these goals has been materials. The differences in approach among the three major participants are their technological features, including electrodes, matrices, intercell cooling, bipolar/separator plates, electrolyte management, fuel selection and system design philosophy.

  3. Influence of the molecular parameters of anionic acrylamide copolymers on the value of the Thoms effect in direct oil emulsions

    NASA Astrophysics Data System (ADS)

    Chichkanov, S. V.; Shamsullin, A. I.; Myagchenkov, V. A.

    2007-05-01

    The influence of molecular parameters (molecular weight and polydispersity in molecular weight) on the value of the reduced Thoms effect in 10% direct oil emulsions has been analyzed with the example of the specimens of anionic acrylamide copolymer of different molecular weight, which were obtained by the ultrasonic-destruction method. The prospects of anionic acrylamide copolymers for use as admixtures reducing the drag of turbulent oil-emulsion flows have been noted for the complex heterophase system studied.

  4. ASSESSMENT OF LIQUID EMULSION MEMBRANE FOR CLEAN UP OF AQUEOUS WASTE EFFLUENTS FROM HAZARDOUS ELEMENTS

    SciTech Connect

    El-Reefy, Sohair A.; Selim, Y.T.; Hassan, M.A.; Aly, H.F.

    2003-02-27

    Four liquid emulsion membrane (LEM) systems are given to remove different hazardous elements such as uranium, thorium, cobalt, copper, lead, and cadmium from different aqueous waste effluents. The optimum conditions for use of these systems are deduced. The potentiality of LEM for removal of hazardous pollutants from aqueous waste solutions is given.

  5. Study of emulsion stabilization by graft copolymers using the optical analyzer Turbiscan.

    PubMed

    Lemarchand, Caroline; Couvreur, Patrick; Vauthier, Christine; Costantini, Dominique; Gref, Ruxandra

    2003-03-18

    Oil-in-water nanoemulsions were prepared using a series of synthetic graft copolymers with a backbone of dextran (DEX) and a number of side chains of poly-epsilon-caprolactone (PCL). In this paper, we focus on the o/w emulsion stabilizing abilities of these novel PCL-DEX copolymers, using a recently developed optical analyzer (Turbiscan). The main advantage of Turbiscan is to detect the destabilization phenomena in non-diluted emulsion, much earlier than the naked eye's operator, especially in the case of an opaque and concentrated system. This study shows that PCL-DEX copolymers successfully stabilized ethyl acetate-in-water emulsions, even in the absence of additional surfactants, whereas they were not efficient in stabilizing methylene chloride-in-water emulsions which coalesced fast and irreversibly. The ethyl acetate-in-water emulsion stabilizing ability of PCL-DEX seemed to be related to the localization of their blocks with regard to the oil-water interface.

  6. Preparation of poly(N-isopropylacrylamide) emulsion gels and their drug release behaviors.

    PubMed

    Tokuyama, Hideaki; Kato, Yuya

    2008-11-15

    Stimuli-sensitive drug delivery systems (DDSs) have attracted considerable attention in medical and pharmaceutical fields; thermosensitive DDS dealing with poly(N-isopropylacrylamide) (poly(NIPA)) have been widely studied. Novel NIPA emulsion gels, i.e., NIPA hydrogels containing distributed oil (oleyl alcohol) microdroplets, were synthesized by means of an emulsion-gelation method in which the polymerization of hydrogels in an aqueous phase in an oil-in-water (O/W) emulsion and the loading of a lipophilic drug (indomethacin) dissolved in an oil phase were accomplished simultaneously. The pulsatile (on-off) drug release from the NIPA emulsion gel loading indomethacin to a phosphate buffered saline (PBS) solution was successfully controlled by a temperature swing between 25 degrees C (release off) and 40 degrees C (release on). The mechanism of the pulsatile drug release was discussed in relation to the diffusion rate, distribution ratio, solvent exchange of NIPA hydrogels, and drug release from an NIPA organogel. The mechanism was as follows: the solvent exchange occurred within the NIPA emulsion gel (the NIPA gel-network absorbed oleyl alcohol with indomethacin) at temperatures above the LCST, and the diffusion rate of indomethacin through the solvent-exchanged gel was higher at 40 degrees C than at 25 degrees C.

  7. Particulate Coacervation of Associative Polymer Brushes-Grafted Nanoparticles To Produce Structurally Stable Pickering Emulsions.

    PubMed

    Yang, Taeseung; Choi, Sang Koo; Park, Daehwan; Lee, Yea Ram; Chung, Chan Bok; Kim, Jin Woong

    2016-12-20

    This study introduces a new type of associative nanoparticle (ANP) that provides controlled chain-to-chain attraction with an associative polymer rheology modifier (APRM) to produce highly stable Pickering emulsions. The ANPs were synthesized by grafting hydrophobically modified hygroscopic zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine-co-stearyl methacrylate) brushes onto 20 nm sized silica NPs via surface-mediated living radical polymerization. The ANP-stabilized Pickering emulsions show significant viscosity enhancement in the presence of the APRM. This indicates that the ANPs act as particulate concentration agents at the interface owing to their hydrophobic association with the APRM in the aqueous phase, which leads to the generation of an ANP-mediated complex colloidal film. Consequently, the described ANP-reinforced Pickering emulsion system exhibits improved resistance to pH and salinity changes. This coacervation approach is advantageous because the complex colloidal layer at the interface provides the emulsion drops with a mechanically robust barrier, thus guaranteeing the improved Pickering emulsion stability against harsh environmental factors.

  8. Influence of emulsification process on the properties of Pickering emulsions stabilized by layered double hydroxide particles.

    PubMed

    Zhang, Nana; Zhang, Li; Sun, Dejun

    2015-04-28

    This paper reports the influence of emulsification process on the packing of layered double hydroxide (LDH) particles at the aqueous/oil phase interface and the properties of the resulting Pickering emulsions. Emulsions prepared by ultrasonication display superior long-term stability and gel-like characteristics at the dispersed phase volume fraction well below the random close packing limit, whereas emulsions with same compositions prepared by vortex mixing show some extent of sedimentation and liquid-like behaviors. Rheological measurements demonstrate that the zero-shear elastic modulus and yield stress of gel-like emulsions exhibit power-law dependences on particle concentration and independence on aqueous/oil phase ratio. The microstructural origin of this behavior is investigated by optical microscopy, revealing the droplets become strongly adhesive and a heterogeneous percolating network is formed among neighboring droplets. Fluorescent confocal microscopy measurements further confirm that the droplet adhesion is due to particle layers bridging opposite interfaces. In contrast, homogeneous, isolated, and densely packed droplets are present in emulsions prepared by vortex mixing, which results in these systems being dominantly viscous like the suspending fluid. This study shows that the emulsification process can be used as a trigger to modify long-term stability and rheology of solid-stabilized multiphase mixtures, which greatly expands their potential technological applications.

  9. A programmable microenvironment for cellular studies via microfluidics-generated double emulsions.

    PubMed

    Zhang, Ying; Ho, Yi-Ping; Chiu, Ya-Ling; Chan, Hon Fai; Chlebina, Ben; Schuhmann, Tom; You, Lingchong; Leong, Kam W

    2013-06-01

    High throughput cellular studies require small sample volume to reduce costs and enhance sensitivity. Microfluidics-generated water-in-oil (W/O) single emulsion droplet systems, in particular, provide uniform, well defined and discrete microenvironment for cell culture, screening, and sorting. However, these single emulsion droplets are incapable of continuous supply of nutrient molecule and are not compatible with aqueous phase-based analysis. A solution is to entrap W/O droplets in another aqueous phase, forming water-in-oil-in-water (W/O/W) double emulsions. The external aqueous phase efficiently prevents desiccation and reduces the amount of organic component, and yet retaining the advantages of compartmentalization. The internal environment can also be programmed dynamically without the need of rupturing the droplets. In this study, we explore the potential application of W/O/W double emulsion droplets for cell cultivation, genetic activation and study of more complicated biological events such as bacteria quorum-sensing as an example. This study demonstrates the advantages and potential application of double emulsion for the study of complex biological processes.

  10. Infrared Spectroscopy of Bilberry Extract Water-in-Oil Emulsions: Sensing the Water-Oil Interface

    PubMed Central

    Kiefer, Johannes; Frank, Kerstin; Zehentbauer, Florian M.; Schuchmann, Heike P.

    2016-01-01

    Water-in-oil (w/o) emulsions are of great interest in many areas of the life sciences, including food technology, bioprocess engineering, and pharmaceuticals. Such emulsions are complex multi-component systems and the molecular mechanisms which lead to a stable emulsion are yet to be fully understood. In this work, attenuated total reflection (ATR) infrared (IR) spectroscopy is applied to a series of w/o emulsions of an aqueous anthocyanin-rich bilberry extract dispersed in a medium chain triglyceride (MCT) oil phase. The content of the emulsifier polyglycerin-polyricinoleat (PGPR) has been varied systematically in order to investigate whether or not its concentration has an impact on the molecular stabilization mechanisms. The molecular stabilization is accessed by a careful analysis of the IR spectrum, where changes in the vibrational frequencies and signal strengths indicate alterations of the molecular environment at the water/oil interface. The results suggest that adding emulsifier in excess of 1% by weight does not lead to an enhanced stabilization of the emulsion. PMID:27089376

  11. Effects of oil on aqueous foams: electrical conductivity of foamed emulsions.

    PubMed

    Yan, Yong-Li; Shan, Cheng; Wang, Yao; Deng, Qiang

    2014-10-06

    Three-phase foams containing dispersed oils (also called foamed emulsion) are usually encountered in such areas as enhanced oil recovery, food foams, and in foams containing antifoams. The presence of oil causes these complex fluids to exhibit extraordinary properties in contrast to aqueous foams. We experimentally investigated, for the first time, the conductive properties of the foamed emulsions and found that the electrical conductivity increases monotonically with the volumetric liquid fraction, presenting a linear relationship. Combined with the analysis on the foaming capacity and microstructure of this complex fluid, the conductive mechanism is revealed. In these foamed emulsions, the whole conductive network is comprised of two levels of structural hierarchy, which displays a different mechanism from those of the conventional aqueous foams. The lamella of emulsions is taken as primary electrical channel, whereas the secondary electrical channel occurs in the lamella between two bubbles. This conductive behaviour is attributed to the microstructure properties of the foamed emulsions. We believe that such findings are potentially important for a better understanding of the fundamentals of these tri-phase dispersion systems.

  12. Fischer-Tropsch diesel emulsions stabilised by microfibrillated cellulose and nonionic surfactants.

    PubMed

    Lif, Anna; Stenstad, Per; Syverud, Kristin; Nydén, Magnus; Holmberg, Krister

    2010-12-15

    Water-in-diesel emulsion fuels have been prepared with a combination of sorbitan monolaurate and glycerol monooleate as emulsifier and with microfibrillated cellulose (MFC) of different hydrophilic/hydrophobic character as stabilizer. The MFC was treated with either octadecylamine or poly(styrene-co-maleic anhydride), resulting in very hydrophobic fibrils. The most stable emulsion was achieved with a combination of hydrophilic (untreated) and hydrophobic MFC and only minute amounts of the stabilizer gave a pronounced effect. Even with the optimized formulation the lifetime of the emulsion was shorter than previously reported when a conventional polymeric stabilizer was used, however. The water drop sizes in the emulsions were determined by three methods: optical images, light scattering, and NMR diffusometry. All three methods gave water drops sizes of ca 2 μm. The NMR diffusometry indicated that besides the micrometer-sized emulsion drops a significant fraction of the water is present in small droplets of micelle size. The chemical exchange of water between these two populations of pools is believed to be the reason for the relatively low stability of the system.

  13. Enhanced antimalarial activity by a novel artemether-lumefantrine lipid emulsion for parenteral administration.

    PubMed

    Ma, Yufan; Lu, Tingli; Zhao, Wen; Wang, Ying; Chen, Ting; Mei, Qibing; Chen, Tao

    2014-10-01

    Artemether and lumefantrine (also known as benflumetol) are difficult to formulate for parenteral administration because of their low aqueous solubility. Cremophor EL as an emulsion excipient has been shown to cause serious side effects. This study reports a method of preparation and the therapeutic efficacies of novel lipid emulsion (LE) delivery systems with artemether, lumefantrine, or artemether in combination with lumefantrine, for parenteral administration. Their physical and chemical stabilities were also evaluated. Furthermore, the in vivo antimalarial activities of the lipid emulsions developed were tested in Plasmodium berghei-infected mice. Artemether, lumefantrine, or artemether in combination with lumefantrine was encapsulated in an oil phase, and the in vivo performance was assessed by comparison with artesunate for injection. It was found that the lumefantrine lipid emulsion (LUM-LE) and artemether-lumefantrine lipid emulsion (ARM-LUM-LE-3) (1:6) began to decrease the parasitemia levels after only 3 days, and the parasitemia inhibition was 90% at doses of 0.32 and 0.27 mg/kg, respectively, with immediate antimalarial effects greater than those of the positive-control group and constant antimalarial effects over 30 days. LUM-LE and ARM-LUM-LE-3 demonstrated the best performance in terms of chemical and physical stabilities and antiplasmodial efficacy, with a mean particle size of 150 nm, and they have many favorable properties for parenteral administration, such as biocompatibility, physical stability, and ease of preparation.

  14. Homogeneous vs. heterogeneous nucleation in water-dicarboxylic acid systems

    NASA Astrophysics Data System (ADS)

    Hienola, A. I.; Vehkamäki, H.; Riipinen, I.; Kulmala, M.

    2009-03-01

    Binary heterogeneous nucleation of water-succinic/glutaric/malonic/adipic acid on nanometer-sized particles is investigated within the frame of classical heterogeneous nucleation theory. Homogeneous nucleation is also included for comparison. It is found that the nucleation probabilities depend on the contact angle and on the size of the seed particles. New thermodynamical properties, such as saturation vapor pressure, density and surface tension for all the dicarboxylic acid aqueous solutions are included in the calculations. While the new surface tension and density formulations do not bring any significant difference in the computed nucleation rate for homogeneous nucleation for succinic and glutaric acids, the use of the newly derived equations for the vapor pressure decrease the acid concentrations in gas phase by 3 orders of magnitude. According to our calculations, the binary heterogeneous nucleation of succinic acid-water and glutaric acid-water - although it requires a 3-4 orders of magnitude lower vapor concentrations than the homogeneous nucleation - cannot take place under atmospheric conditions. On the other hand binary homogeneous nucleation of adipic acid-water systems might be possible under conditions occuring in upper boundary layer. However, a more detailed characterization of the interaction between the surface and the molecules of the nucleating vapor should be considered in the future.

  15. Benefits and risks of folic acid to the nervous system

    PubMed Central

    Reynolds, E

    2002-01-01

    During three decades of neurological practice I have witnessed a remarkable change in attitudes to the benefits and risks of folic acid therapy in nervous system disorders. In the 1960s all that was known and taught was that folic acid was harmful to the nervous system, especially in precipitating or exacerbating the neurological complications of vitamin B12 deficiency. So deeply held was this view that the possibility of neuropsychological benefits from this vitamin was initially viewed with considerable scepticism.1 PMID:11971038

  16. Lead/acid batteries in systems to improve power quality

    NASA Astrophysics Data System (ADS)

    Taylor, P.; Butler, P.; Nerbun, W.

    Increasing dependence on computer technology is driving needs for extremely high-quality power to prevent loss of information, material, and workers' time that represent billions of dollars annually. This cost has motivated commercial and Federal research and development of energy storage systems that detect and respond to power-quality failures in milliseconds. Electrochemical batteries are among the storage media under investigation for these systems. Battery energy storage systems that employ either flooded lead/acid or valve-regulated lead/acid battery technologies are becoming commercially available to capture a share of this emerging market. Cooperative research and development between the US Department of Energy and private industry have led to installations of lead/acid-based battery energy storage systems to improve power quality at utility and industrial sites and commercial development of fully integrated, modular battery energy storage system products for power quality. One such system by AC Battery Corporation, called the PQ2000, is installed at a test site at Pacific Gas and Electric Company (San Ramon, CA, USA) and at a customer site at Oglethorpe Power Corporation (Tucker, GA, USA). The PQ2000 employs off-the-shelf power electronics in an integrated methodology to control the factors that affect the performance and service life of production-model, low-maintenance, flooded lead/acid batteries. This system, and other members of this first generation of lead/acid-based energy storage systems, will need to compete vigorously for a share of an expanding, yet very aggressive, power quality market.

  17. Phorbic Acid Biosynthesis in the Latex Vessel System of Euphorbia

    PubMed Central

    Nordal, Arnold; Benson, A. A.

    1969-01-01

    Evidence is presented that phorbic acid is formed in the latex producing cell system, rather than in photosynthetic or chlorophyll-free tissues of Euphorbia resinifera Berg. When a branch of the plant was kept first in a 14CO2 atmosphere with 12 hr light-dark periods for 2 days and then left under natural conditions in the air outside for at least 2 to 3 days, radioactive phorbic acid was found in the latex. Phorbic acid synthesis appeared to be independent of the photosynthetic and respiratory activities of the plant. Besides phorbic acid 2 other major radioactive compounds were recognized in the latex, a glycoside or oligosaccharide, and a lipid belonging to the group of triterpenoid compounds characteristic of the latex in several species of Euphorbia. Images PMID:16657036

  18. The use of IV lipid emulsion for lipophilic drug toxicities.

    PubMed

    Kaplan, Amy; Whelan, Megan

    2012-01-01

    IV lipid emulsion (ILE) therapy is emerging as a potential antidote for lipophilic drug toxicities in both human and veterinary medicine. ILE has already gained acceptance in human medicine as a treatment of local anesthetic systemic toxicity, but its mechanism of action, safety margins, and standardized dosing information remains undetermined at this time. Experimental and anecdotal use of ILE in the human and veterinary literature, theorized mechanisms of action, current dosing recommendations, potential adverse effects, and indications for use in human and veterinary emergency medicine are reviewed herein.

  19. Vorticity alignment and negative normal stresses in sheared attractive emulsions.

    PubMed

    Montesi, Alberto; Peña, Alejandro A; Pasquali, Matteo

    2004-02-06

    Attractive emulsions near the colloidal glass transition are investigated by rheometry and optical microscopy under shear. We find that (i) the apparent viscosity eta drops with increasing shear rate, then remains approximately constant in a range of shear rates, then continues to decay; (ii) the first normal stress difference N1 transitions sharply from nearly zero to negative in the region of constant shear viscosity; and (iii) correspondingly, cylindrical flocs form, align along the vorticity, and undergo a log-rolling movement. An analysis of the interplay between steric constraints, attractive forces, and composition explains this behavior, which seems universal to several other complex systems.

  20. The influence of dietary docosahexaenoic acid and arachidonic acid on central nervous system polyunsaturated fatty acid composition.

    PubMed

    Brenna, J Thomas; Diau, Guan-Yeu

    2007-01-01

    Numerous studies on perinatal long-chain polyunsaturated fatty acid nutrition have clarified the influence of dietary docosahexaenoic acid (DHA) and arachidonic acid (ARA) on central nervous system PUFA concentrations. In humans, omnivorous primates, and piglets, DHA and ARA plasma and red blood cells concentrations rise with dietary preformed DHA and ARA. Brain and retina DHA are responsive to diet while ARA is not. DHA is at highest concentration in cells and tissues associated with high energy consumption, consistent with high DHA levels in mitochondria and synaptosomes. DHA is a substrate for docosanoids, signaling compounds of intense current interest. The high concentration in tissues with high rates of oxidative metabolism may be explained by a critical role related to oxidative metabolism.

  1. The Influence of Dietary Docosahexaenoic Acid and Arachidonic Acid on Central Nervous System Polyunsaturated Fatty Acid Composition

    PubMed Central

    Brenna, J. Thomas; Diau, Guan-Yeu

    2007-01-01

    Numerous studies on perinatal long chain polyunsaturated fatty acid nutrition have clarified the influence of dietary docosahexaenoic acid (DHA) and arachidonic acid (ARA) on central nervous system PUFA concentrations. In humans, omnivorous primates, and piglets, DHA and ARA plasma and red blood cells concentrations rise with dietary preformed DHA and ARA. Brain and retina DHA are responsive to diet while ARA is not. DHA is at highest concentration cells and tissues associated with high energy consumption, consistent with high DHA levels in mitochondria and synaptosomes. DHA is a substrate for docosanoids, signaling compounds of intense current interest. The high concentration in tissues with high rates of oxidative metabolism may be explained by a critical role related to oxidative metabolism. PMID:18023566

  2. Study of Self Assembly Systems Formed by Malic Acid and Alkyloxy Benzoic Acids

    NASA Astrophysics Data System (ADS)

    Vijayakumar, Vellalapalayam Nallagounder; Madhu Mohan, Mathukumalli Lakshmi Narayana

    2010-12-01

    Self assembly systems formed by malic acid and alkyloxy benzoic acids are characterized. The ferroelectric ingredient malic acid formed double hydrogen bond with p-n-alkyloxy benzoic acids. Various hydrogen bonded complexes have been synthesized with malic acid and pentyl to dodecyloxy benzoic acid, respectively. Fourier transformation infrared (FTIR) studies confirm the hydrogen bond formation. Polarizing optical microscopic (POM) studies revealed the textural information while the transition and enthalpy values are calculated from differential scanning calorimetry (DSC) studies. A phase diagram has been constructed from the POMand DSC studies. A new smectic ordering, smectic X*, has been identified which exhibits a finger print type texture. This phase has been characterized by POM, DSC, helix, and tilt angle studies. The transition from traditional cholesteric to smectic X* phase is observed to be first order. The tilt angle data in this phase has been fitted to a power law and the temperature variation of the tilt angle follows mean field theory predictions. The results of FTIR, POM, DSC, tilt angle, and helicoidal studies are discussed.

  3. Difference between Chitosan Hydrogels via Alkaline and Acidic Solvent Systems

    PubMed Central

    Nie, Jingyi; Wang, Zhengke; Hu, Qiaoling

    2016-01-01

    Chitosan (CS) has generated considerable interest for its desirable properties and wide applications. Hydrogel has been proven to be a major and vital form in the applications of CS materials. Among various types of CS hydrogels, physical cross-linked CS hydrogels are popular, because they avoided the potential toxicity and sacrifice of intrinsic properties caused by cross-linking or reinforcements. Alkaline solvent system and acidic solvent system are two important solvent systems for the preparation of physical cross-linked CS hydrogels, and also lay the foundations of CS hydrogel-based materials in many aspects. As members of physical cross-linked CS hydrogels, gel material via alkaline solvent system showed significant differences from that via acidic solvent system, but the reasons behind are still unexplored. In the present work, we studied the difference between CS hydrogel via alkaline system and acidic system, in terms of gelation process, hydrogel structure and mechanical property. In-situ/pseudo in-situ studies were carried out, including fluorescent imaging of gelation process, which provided dynamic visualization. Finally, the reasons behind the differences were explained, accompanied by the discussion about design strategy based on gelation behavior of the two systems. PMID:27786262

  4. Difference between Chitosan Hydrogels via Alkaline and Acidic Solvent Systems

    NASA Astrophysics Data System (ADS)

    Nie, Jingyi; Wang, Zhengke; Hu, Qiaoling

    2016-10-01

    Chitosan (CS) has generated considerable interest for its desirable properties and wide applications. Hydrogel has been proven to be a major and vital form in the applications of CS materials. Among various types of CS hydrogels, physical cross-linked CS hydrogels are popular, because they avoided the potential toxicity and sacrifice of intrinsic properties caused by cross-linking or reinforcements. Alkaline solvent system and acidic solvent system are two important solvent systems for the preparation of physical cross-linked CS hydrogels, and also lay the foundations of CS hydrogel-based materials in many aspects. As members of physical cross-linked CS hydrogels, gel material via alkaline solvent system showed significant differences from that via acidic solvent system, but the reasons behind are still unexplored. In the present work, we studied the difference between CS hydrogel via alkaline system and acidic system, in terms of gelation process, hydrogel structure and mechanical property. In-situ/pseudo in-situ studies were carried out, including fluorescent imaging of gelation process, which provided dynamic visualization. Finally, the reasons behind the differences were explained, accompanied by the discussion about design strategy based on gelation behavior of the two systems.

  5. High temperature structural, polymeric foams from high internal emulsion polymerization

    SciTech Connect

    Hoisington, M.A.; Duke, J.R.; Apen, P.G.

    1996-02-01

    In 1982, a high internal phase emulsion (HIPE) polymerization process to manufacture microcellular, polymeric foam systems was patented by Unilever. This patent discloses a polymerization process that occurs in a water-in-oil emulsion in which the water represents at least 76% of the emulsion by volume. The oil phase consists of vinyl monomers such as styrene and acrylates that are crosslinked by divinyl monomers during polymerization. After polymerization and drying to remove the water phase, the result is a crosslinked polymer foam with an open cell microstructure that is homogeneous throughout in terms of morphology, density, and mechanical properties. Since 1982, numerous patents have examined various HIPE polymerized foam processing techniques and applications that include absorbents for body fluids, cleaning materials, and ion exchange systems. All the published HIPE polymerized foams have concentrated on materials for low temperature applications. Copolymerization of styrene with maleic anhydride and N-substituted maleimides to produce heat resistant thermoplastics has been studied extensively. These investigations have shown that styrene will free radically copolymerize with N-substituted maleimides to create an alternating thermoplastic copolymer with a Tg of approximately 200{degrees}C. However, there are many difficulties in attempting the maleimide styrene copolymerization in a HIPE such as lower polymerization temperatures, maleimide solubility difficulties in both styrene and water, and difficulty obtaining a stable HIPE with a styrene/maleimide oil phase. This work describes the preparation of copolymer foams from N-ethylmaleimide and Bis(3-ethyl-5-methyl-4-maleimide-phenyl)methane with styrene based monomers and crosslinking agents.

  6. The effects of oil, dispersant, and emulsions on the survival and behavior of an estuarine teleost and an intertidal amphipod

    SciTech Connect

    Butler, R.G.; Trivelpiece, W.; Miller, D.S.

    1982-04-01

    Killfish (Fundulus heteroclitus) and amphipods (Gammarus oceanicus) were exposed seperately to either a No. 2 fuel oil, AP dispersant, or emulsions of the two in a static system. Both species exhibited a concentration-dependent response to all three treatments. However, emulsification of oil with dispersant clearly increased its lethal effect on killfish survival, but did not cause a differential change in behavioral parameters such as schooling, chafing, substrate nipping, activity, or depth preference. Killfish exposed to conditions of thermal or osmotic stress were more sensitive to the lethal effects of emulsions. In contrast, emulsions caused quantitative changes in amphipod activity and precopulatory behavior, but did not increase mortality beyond that caused by exposure to oil alone. Changes in salinity had little effect on amphipod sensitivity to emulsions, but decreasing temperature did result in increased survival.

  7. Impact of starch-based emulsions on the antibacterial efficacies of nisin and thymol in cantaloupe juice.

    PubMed

    Sarkar, Preetam; Bhunia, Arun K; Yao, Yuan

    2017-02-15

    The use of antimicrobial compounds to prevent foodborne pathogens from contaminating fresh-cut produce has received broad attentions; however, the applications of these compounds are hindered by their rapid depletion in foods. To prolong their efficacies, the use of delivery systems is essential. In this study, oil-in-water emulsions formed using starch octenyl succinate (starch-OS) were used to stabilize nisin and thymol in cantaloupe juice-containing fluid. Listeria monocytogenes V7 and Salmonella enterica serovar Typhimurium were used as model pathogens to evaluate the antimicrobial activities of nisin and thymol formulations in cantaloupe juice. The results showed that the emulsions had much greater capability to retain nisin and thymol over the storage and displayed much greater effect to inhibit Listeria and Salmonella than non-emulsion, aqueous formulations. Starch-OS based emulsions not only retained nisin and thymol activities separately, but also exhibited their cooperative antibacterial effects.

  8. Preparation of a multiple emulsion based on pectin-whey protein complex for encapsulation of saffron extract nanodroplets.

    PubMed

    Faridi Esfanjani, Afshin; Jafari, Seid Mahdi; Assadpour, Elham

    2017-04-15

    The present study illustrates a simple and practical way to produce an adequate delivery system of bioactive compounds of saffron by protein-polysaccharide complex. Frist, crocin, safranal, and picrocrocin were loaded in nanodroplets (<100nm) by using water in oil (W/O) microemulsions contain 5, and 10% aqueous saffron extract as a dispersed phase. These microemulsions were then covered with whey protein concentrate (WPC)-maltodextrin or WPC-pectin-maltodextrin through water in oil in water (W/O/W) multiple emulsions. The stability and release of loaded crocin, safranal, and picrocrocin in multiple emulsions were investigated during 22days storage. The produced multiple emulsion by WPC-pectin-maltodextrin along with 5% inner aqueous phase showed a high stability and low release of encapsulated compounds over time. This emulsion also provided a high protection of crocin, safranal, and picrocrocin in the gastric condition.

  9. Dextran-based hydrogel microspheres obtained in w/o emulsion: preparation, characterisation and in vivo studies.

    PubMed

    Casadei, Maria Antonietta; Cesa, Stefania; Pacelli, Settimio; Paolicelli, Patrizia; Tita, Beatrice; Vitali, Federica

    2014-01-01

    The cross-linking reaction in w/o emulsions of dextran (DEX) functionalised with methacrylic groups, having or not acid residues in side chain, can be used to easily prepare polysaccharide hydrogel microspheres with properties suitable for drug delivery applications. The formation of a chemical network within the obtained particles was evaluated with FT-IR spectroscopy, whereas morphology and dimensions of the microspheres were investigated with optical and scanning electron microscopy. At the same time, swelling measurements were carried out on freeze-dried particles in different aqueous media simulating biological fluids. Preliminary release experiments performed with ibuprofen, betamethasone and vitamin B12 chosen as model drugs, showed that these microspheres could be suitable as modified drug delivery systems in oral formulations. Finally, in vivo writhing experiments were carried out in mice in order to verify the antinociceptive activity of betamethasone loaded into the new polysaccharide hydrogel microspheres.

  10. A continuous acetic acid system for polyacrylamide gel electrophoresis of gliadins and other prolamines.

    PubMed

    Clements, R L

    1988-02-01

    A polyacrylamide gel electrophoresis system buffered by acetic acid alone was developed for electrophoresis of prolamines. When applied to gliadin electrophoresis, the acetic acid system produces more bands than does a conventional aluminum lactate-lactic acid system (using 12% acrylamide gels). The acetic acid system is relatively simple, requiring a single buffer component that is universally available in high purity.

  11. 21 CFR 862.3580 - Lysergic acid diethylamide (LSD) test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Lysergic acid diethylamide (LSD) test system. 862... Test Systems § 862.3580 Lysergic acid diethylamide (LSD) test system. (a) Identification. A lysergic acid diethylamide (LSD) test system is a device intended to measure lysergic acid diethylamide,...

  12. 21 CFR 862.3580 - Lysergic acid diethylamide (LSD) test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Lysergic acid diethylamide (LSD) test system. 862... Test Systems § 862.3580 Lysergic acid diethylamide (LSD) test system. (a) Identification. A lysergic acid diethylamide (LSD) test system is a device intended to measure lysergic acid diethylamide,...

  13. 21 CFR 862.3580 - Lysergic acid diethylamide (LSD) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lysergic acid diethylamide (LSD) test system. 862... Test Systems § 862.3580 Lysergic acid diethylamide (LSD) test system. (a) Identification. A lysergic acid diethylamide (LSD) test system is a device intended to measure lysergic acid diethylamide,...

  14. 21 CFR 862.3580 - Lysergic acid diethylamide (LSD) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Lysergic acid diethylamide (LSD) test system. 862... Test Systems § 862.3580 Lysergic acid diethylamide (LSD) test system. (a) Identification. A lysergic acid diethylamide (LSD) test system is a device intended to measure lysergic acid diethylamide,...

  15. 21 CFR 862.3580 - Lysergic acid diethylamide (LSD) test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Lysergic acid diethylamide (LSD) test system. 862... Test Systems § 862.3580 Lysergic acid diethylamide (LSD) test system. (a) Identification. A lysergic acid diethylamide (LSD) test system is a device intended to measure lysergic acid diethylamide,...

  16. High Level Waste System Impacts from Acid Dissolution of Sludge

    SciTech Connect

    KETUSKY, EDWARD

    2006-04-20

    This research evaluates the ability of OLI{copyright} equilibrium based software to forecast Savannah River Site High Level Waste system impacts from oxalic acid dissolution of Tank 1-15 sludge heels. Without further laboratory and field testing, only the use of oxalic acid can be considered plausible to support sludge heel dissolution on multiple tanks. Using OLI{copyright} and available test results, a dissolution model is constructed and validated. Material and energy balances, coupled with the model, identify potential safety concerns. Overpressurization and overheating are shown to be unlikely. Corrosion induced hydrogen could, however, overwhelm the tank ventilation. While pH adjustment can restore the minimal hydrogen generation, resultant precipitates will notably increase the sludge volume. OLI{copyright} is used to develop a flowsheet such that additional sludge vitrification canisters and other negative system impacts are minimized. Sensitivity analyses are used to assess the processability impacts from variations in the sludge/quantities of acids.

  17. Nuclear emulsions as a very high resolution detector for directional dark matter search

    NASA Astrophysics Data System (ADS)

    D'Ambrosio, N.; Di Marco, N.; Pupilli, F.; Alexandrov, A.; De Lellis, G.; Di Crescenzo, A.; Tioukov, V.; Sirignano, C.; Naka, T.; Asada, T.; Katsuragawa, T.; Yoshimoto, M.; Hakamata, K.; Ishikawa, M.; Kuwabara, K.; Umemoto, A.; Furuya, S.; Machii, S.; Tawara, Y.

    2014-01-01

    The use of nuclear emulsions in particle physics dates back to the very early stages. They are now used when an extremely high position resolution is required like in the search for short lived particles. The capability to detect nuclear recoils induced by WIMPs relies on the possibility to detect sub-micrometric trajectories. Recently nuclear emulsions with silver grains of 20 nm diameter were developed, opening the way for the reconstruction of nanometric particles. This challenging purpose requires the development of fully automated optical readout systems for a fast scanning of the emulsion films. This is meant for a pre-selection of recoil candidates. Once candidates have been identified, a fine grained X-ray microscope is used to detect the grains making up the tracks. We report here the present results on the current development along this line.

  18. Optical transmission measurements for in-line monitoring of turbid oil-water emulsions

    NASA Astrophysics Data System (ADS)

    Metz, Philipp; Dopf, Katja; Aichholz, Markus; Riedel, Boris; Lemmer, Uli; Freudig, Barbara; Zimmermann, Clifton; Gerken, Martina

    2014-05-01

    For absorbing media the concentration may be calculated directly from the optical transmission following the logarithmic dependence given in the Lambert-Beer law. Due to multiple scattering events in oil-water emulsions (e.g. milk, cream, etc.), these exhibit a nonlinear relationship between the attenuation and the oil concentration. We demonstrate that for increasing oil content in oil-water emulsions the attenuation first increases, then levels out, and finally even decreases for a fat content of 60%. Single-wavelength optical transmission measurements are found to be well suited for the in-line monitoring of oil-water emulsions of fat contents below 20%, e.g., for the in-line fat content monitoring of milk. Using experiments and ray-tracing simulations we evaluate system optimization.

  19. Micro-emultocrit technique: a valuable tool for determination of critical HLB value of emulsions.

    PubMed

    Macedo, Janus P F; Fernandes, Leonardo L; Formiga, Fábio R; Reis, Michael F; Júnior, Toshiyuiky Nagashima; Soares, Luiz A L; Egito, E Socrates T

    2006-03-10

    The aim of this work was to develop a methodology for rapid determination of the critical hydrophilic-lipophilic balance (HLB) value of lipophilic fractions of emulsions. The emulsions were prepared by the spontaneous emulsification process with HLB value from 4.3 to 16.7. The preparations were stored at 2 different temperatures (25 degrees C and 4 degrees C) and their physicochemical behavior was evaluated by the micro-emultocrit technique and the long-term stability study. The experimental data show a reverse relationship between HLB values of the surfactant mixtures and emulsion stability. A close correlation between the results for both stability procedures was observed, suggesting the use of micro-emultocrit to predict stabilities of such systems. In addition, it was found that the critical HLB of the Mygliol 812 was 15.367.

  20. Phase inversion of ionomer-stabilized emulsions to form high internal phase emulsions (HIPEs).

    PubMed

    Zhang, Tao; Xu, Zhiguang; Cai, Zengxiao; Guo, Qipeng

    2015-06-28

    Herein, we report the phase inversion of ionomer-stabilized emulsions to form high internal phase emulsions (HIPEs) induced by salt concentration and pH changes. The ionomers are sulfonated polystyrenes (SPSs) with different sulfonation degrees. The emulsion types were determined by conductivity measurements, confocal microscopy and optical microscopy, and the formation of HIPE organogels was verified by the tube-inversion method and rheological measurements. SPSs with high sulfonation degrees (water-soluble) and low sulfonation degrees (water-insoluble) can stabilize oil-in-water emulsions; these emulsions were transformed into water-in-oil HIPEs by varying salt concentrations and/or changing the pH. SPS, with a sulfonation degree of 11.6%, is the most efficient, and as low as 0.2 (w/v)% of the organic phase is enough to stabilize the HIPEs. Phase inversion of the oil-in-water emulsions occurred to form water-in-oil HIPEs by increasing the salt concentration in the aqueous phase. Two phase inversion points from oil-in-water emulsions to water-in-oil HIPEs were observed at pH 1 and 13. Moreover, synergetic effects between the salt concentration and pH changes occurred upon the inversion of the emulsion type. The organic phase can be a variety of organic solvents, including toluene, xylene, chloroform, dichloroethane, dichloromethane and anisole, as well as monomers such as styrene, butyl acrylate, methyl methacrylate and ethylene glycol dimethacrylate. Poly(HIPEs) were successfully prepared by the polymerization of monomers as the continuous phase in the ionomer-stabilized HIPEs.