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The intent of this study was to evaluate changes on interfacial properties of W1/O/W2 systems containing different emulsifiers and bioactive compounds. Interactions of Vitamin D3 (VitD3) and Phytosterols at interfaces containing mixtures of PGPR and β-lactoglobulin or sodium caseinate were evaluated. The oil-water interfacial properties were dominated by PGPR, even with the synergistic effect of the proteins to decrease the interfacial tension. These bioactives altered the interfacial properties. Double emulsions supplemented with these compounds resulted in increased short term stability, suggesting an interaction between bioactives with the emulsifiers at the interface. The in vitro digestion of emulsions loaded with multiple bioactives were evaluated in relation to the physico-chemical changes as well as the bioactive release behavior. Gastric digestion did not affect the size distribution of the emulsions, however, most of the Vitamin B12 (VitB12) entrapped in the inner aqueous phase was released during this stage. Phytosterols transfer was well correlated to lipid digestion, while VitD3 was found to be significantly lower. Different hydrophobic compounds resulted in different transfer behavior being dependant in their partitioning towards the core or the interface of the oil droplet. Changes in the physical state of the oil and water internal phases of W1/O/W2 emulsions were evaluated by structuring them with gelation techniques. Similarly, the emulsions were stable during the gastric stage. When oil-fat gel was used, elongated structures (fat crystals) were visible and the droplets were not spherical. Coalescence of the liquid W1 was observed with no relation to the physical state of the oil phase. W1/O/W2 droplets were found up to early stages of duodenal stage. Between 5 and 25 min of duodenal stage, single non spherical oil droplets with crystals present were observed. Emulsions with oil-fat gel lipid phase resulted in higher levels of lipid digestion and bioactive transfer. The presence of medium chain fatty acids and the surface-to-core distribution of the hydrophobic bioactive influenced the lipid digestibility and bioaccessibility of the hydrophobic compounds. Gelling the inner aqueous phase revealed lower values of VitB12 released in the gastric stage and it was driven by the aqueous gel properties. Natural Sciences and Engineering Research Council of Canada; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) - Science Without Borders Program of Ministry of Education - Brazil

Magnetic nanoparticles are effective delivery systems to target therapeutic genes by the attractive forces of magnetic fields. Curative effects depending on dose of nucleic acids or drugs increased, while cytotoxic effects minimized with these systems. In this study, a novel magnetic nanoparticle synthesis method was developed by combining advantages of microemulsion and multiple emulsion methods. Particle size, zeta potential, magnetization, complex formation with nucleic acids, DNase I protection ability, and cytotoxicity levels were examined. At last, magnetic nanoparticles were obtained with a promising synthesis method and it is determined that they are sufficiently small, non-toxic and have optimal surface properties for systemic delivery of nucleic acids., Manyetik nanopartiküller manyetik alanın çekim kuvvetini kullanarak terapötik genleri etkili bir şekilde aktaran sistemlerdir. Bu sistemlerde, ilaç ve nükleik asit dozuna bağlı tedavi edici etki artırılırken, sitotoksik etkiler en aza indirgenir. Bu çalışmada mikroemulsiyon ve çoklu emülsiyon metotlarının avantajları bir araya getirilerek yeni bir manyetik nanopartikül üretim yöntemi geliştirilmiştir. Partikül boyutu, zeta potansiyeli, manyetizasyon değeri, nükleik asitler ile kompleks oluşumu, DNaz I’e karşı koruma yeteneği ve sitotoksisite derecesi araştırılmıştır. Son olarak, manyetik nanopartiküller gelecek vaat eden bir sentez yöntemi ile elde edilmiş ve nükleik asitlerin sistemik taşınması için yeterli derecede küçük boyutta, toksik olmayan ve ideal yüzey özelliklerine sahip oldukları belirlenmiştir., TUBITAK-SBAG-112S294

International audience; Myoglobin (Mb)-loaded poly(ε-caprolactone) (PCL) microparticles were prepared by multiple emulsion with solvent extraction/evaporation method under more or less deleterious operating conditions. The protein integrity was monitored using both UV/Vis absorbance ratio method at specific wavelengths and a conductometric bi-enzymatic biosensor based on proteinase K and pronase. Under standard operating conditions, Mb remained in native conformation, while different degrees of protein denaturation were observed by changing the encapsulation conditions. It was shown that solvent elimination under reduced pressure and in a lower extent addition of a higher molecular weight PCL led to protein alteration. In the first case, the loss of protein integrity can be attributed to residual solvent entrapped in particles whose solidification was accelerated. In the second case, denaturation may be explained by an increase in the protein exposure time at water/organic solvent interface due to an increase in organic phase viscosity.

Interfacial reaction in a multiple emulsion, was carried out with the aim of preparing hollow hydroxyapatite (HAp) microspheres. The multiple emulsion was a W/O/W emulsion, made of dipotassium hydrogen phosphate solution as an inner aqueous phase, cyclohexane as an oil phase, and calcium nitrate solution as an outer aqueous phase. The phase diagrams of Ca(NO_3)2-K_2HPO_4-H_2O system were drawn by thermodynamic computations and used to simulate the chemical process in a multiple emulsion for determining the experimental conditions. Single phase HAp was synthesized at an initial pH of 12.0. HAp with a Ca/P ratio was measured by inductively coupled plasma spectroscopy to correspond to 1.49. The product was composed of microspheres of 0.5 to 2 μm in diameter. Each microsphere was composed of acicular particles with an aspect ratio of 2.5-10 with a short axis length of about 20 nm.

The purpose of the study was to prepare a stable multiple emulsion system containing two skin antiaging agents using a natural oil vitamin C, known to be a very unstable ingredient and is decomposed in the presence of oxygen, was entrapped in the internal aqueous phase of w/o/w multiple emulsion. In this way, vitamin C is expected to exhibit slow release and the effect of vitamin C can be improved as it has been protected from the external environment. The other ingredient, which is a product of wheat protein was also used as an antiaging agent. Both of the ingredients increase the synthesis of collagen fibers in the dermis. Therefore, a synergystic effect can be produced by using the two ingredients in one formulation. In this study, multiple emulsions were prepared by the two-step emulsification method. Basic formulation containing no active material and a formulation containing vitamin C in the internal aqueous phase and wheat protein in the oily phase were prepared. The oil selected was macadamia nut oil since it contains a high quantity of palmitoleic acid which is the natural ingredient of the young skin. Basic formulation as well as the formulation containing active ingredients were stored at different accelerated conditions for six months and characterized. Globule size, pH, viscosity and physical changes were tested to characterize the emulsion systems. Basic emulsion was found to be more stable at all the different conditions than the formulation containing the active ingredients. Özet Bu çalismanin amaci, dogal bir yag kullanarak, iki farkli cilt yaslanmasini geciktirici madde içeren kararli emülsiyon sistemini hazirlamaktir. Çok kararsiz ve oksijen varliginda yapisinin parçalandigi bilinen vitamin C, s/y/s çoklu emülsiyonun iç fazina katilmistir. Bu sekilde, vitamin C’nin yavas salim göstermesi ve çevresel etkenlerden korundugu için etkisinin iyilestirilmesi beklenebilir. Yaslanmayi geciktirici olarak kullanilan diger madde bugday proteini ürünüdür. Her iki madde de dermis’deki kolajen liflerinin sentezini arttirir. Dolayisiyla, tek formülasyonda iki maddeyi kullanarak sinerjik etki olusturulabilir. Bu çalismada, çoklu emülsiyonlar iki-basamakli emülsiyon olusturma yöntemi ile hazirlanmistir. Hazirlanan emülsiyonlar etkin madde içermeyen temel formülasyon ve iç fazinda vitamin C, dis fazinda ise bugday proteini içeren formülasyonlardir. Seçilen yag, genç cildin dogal bileseni olan ve palmitoleik asiti yüksek miktarda içeren makademia findik yagidir. Temel formülasyon ve etkin maddeleri içeren formülasyon, farkli hizlandirilmis kosullarda 6 ay saklanmis ve özellikleri belirlenmistir. Emülsiyon sistemlerin özelliklerini belirlemek için damlacik boyutu, pH, viskozite ve fiziksel degisimler test edilmistir. Temel emülsiyonun tüm kosullarda etkin maddeleri içeren formülasyondan daha kararli oldugu bulunmustur.

Microfluidic devices are promising tools for the production of monodispersed tuneable complex emulsions. This review highlights the advantages of microfluidics for the fabrication of emulsions and presents an overview of the microfluidic emulsification methods including two-step and single-step methods for the fabrication of high-order multiple emulsions (double, triple, quadruple and quintuple) and emulsions with multiple and/or multi-distinct inner cores. The microfluidic methods for the formation of multiple emulsion drops with ultra-thin middle phase, multi-compartment jets, and Janus and ternary drops composed of two or three distinct surface regions are also presented. Different configurations of microfluidic drop makers are covered, such as co-flow, T-junctions and flow focusing (both planar and three-dimensional (3D)). Furthermore, surface modifications of microfluidic channels and different modes of droplet generation are summarized. Non-confined microfluidic geometries used for buoyancy-driven drop generation and membrane integrated microfluidics are also discussed. The review includes parallelization and drop splitting strategies for scaling up microfluidic emulsification. The productivity of a single drop maker is typically 1 L/h, which requires combining drop makers into twodimensional (2D) and 3D assemblies fed from a single set of inlet ports through a network of distribution and collection channels.

Ruma Maji, Niladri Shekhar Dey, Bhabani Sankar Satapathy, Biswajit Mukherjee, Subhasish MondalDepartment of Pharmaceutical Technology, Jadavpur University, Kolkata (Calcutta), IndiaBackground: Four formulations of Tamoxifen citrate loaded polylactide-co-glycolide (PLGA) based nanoparticles (TNPs) were developed and characterized. Their internalization by Michigan Cancer Foundation-7 (MCF-7)breast cancer cells was also investigated.Methods: Nanoparticles were prepared by a multiple emulsion solvent evaporation method. Then the following studies were carried out: drug-excipients interaction using Fourier transform infrared spectroscopy (FTIR), surface morphology by field emission scanning electron micro­scopy (FESEM), zeta potential and size distribution using a Zetasizer Nano ZS90and particle size analyzer, and in vitro drug release. In vitro cellular uptake of nanoparticles was assessed by confocal microscopy and their cell viability (%) was studied.Results: No chemical interaction was observed between the drug and the selected excipients. TNPs had a smooth surface, and a nanosize range (250–380nm) with a negative surface charge. Drug loadings of the prepared particles were1.5%±0.02% weight/weight (w/w),2.68%±0.5% w/w,4.09%±0.2% w/w,27.16%±2.08% w/w for NP1–NP4, respectively. A sustained drug release pattern from the nanoparticles was observed for the entire period of study, ie, up to60days. Further, nanoparticles were internalized well by the MCF-7breast cancer cells on a concentration dependent manner and were present in the cytoplasm. The nucleus was free from nanoparticle entry. Drug loaded nanoparticles were found to be more cytotoxic than the free drug.Conclusion: TNPs (NP4) showed the highest drug loading, released the drug in a sustained manner for a prolonged period of time and were taken up well by the MCF-7breast cancer cell line in vitro. Thus the formulation may be suitable for breast cancer treatment due to the good permeation of the formulation into the breast cancer cells.Keywords: polylactide-co-glycolide nanoparticle, PLGA, breast cancer, multiple emulsion

Food-grade water-in-oil-in-water (W/O/W) multiple emulsions with a volume median diameter of outer droplets of 50-210 mu m were produced by injecting a water-in-oil (W/O) emulsion at the flux of 30 L m(-2) h(-1) through a 10-mu m pore electroplated nickel membrane oscillating at 10-90 Hz frequency and 0.1-5 mm amplitude in 2 wt% aqueous Tween(R) 20 (polyoxyethylene sorbitan monolaurate) solution. The oil phase in the primary W/O emulsion was 5 wt% PGPR (polyglycerol polyricinoleate) dissolved in sunflower oil and the content of water phase in the W/O emulsion was 30 vol%. The size of outer droplets was precisely controlled by the amplitude and frequency of membrane oscillation. Only 3-5% of the inner droplets with a mean diameter of 0.54 mu m were released into the outer aqueous phase during membrane emulsification. A sustained release of 200 ppm copper (II) loaded in the inner aqueous phase was investigated over 7 days. 95% of Cu(II) initially present in the inner water phase was released in the first 2 days from 56-mu m diameter multiple emulsion droplets and less than 15% of Cu(II) was released over the same interval from 122 mu m droplets. The release rate of Cu(II) decreased with increasing the size of outer droplets and followed non-zero-order kinetics with a release exponent of 0.3-0.5. The prepared multiple emulsions can be used for controlled release of hydrophilic actives in the pharmaceutical, food, and cosmetic industry. (C) 2014 Elsevier B.V. All rights reserved. 7th Formula Conference, Jul 01-04, 2013, Mulhouse, France

Emulsões múltiplas complexas possuem excelente habilidade de agregar grandes quantidades de agentes cosméticos funcionais. Este estudo teve por objetivo encapsular grandes volumes de chá verde em uma emulsão múltipla clássica e comparar sua estabilidade com a emulsão múltipla sem o extrato do chá verde. Emulsões múltiplas são desenvolvidas usando cetil dimeticona copoliol como emulsificante lipofílico e o clássico polissorbato-80 como emulsificante hidrofílico. As emulsões múltiplas foram avaliadas por meio de vários aspectos fisico-químicos como condutividade, pH, análise microscópica e reologia. Estas características foram observadas por um período de 30 dias sob diferentes condições de armazenamento. Testes de proteção da pele in vivo e in vitro foram realizados para ambos os tipos de emulsões testadas, i.e. com o ativo em estudo (MeA) e sem ativo (MeB). Ambas as formulações apresentaram características comparáveis no que diz respeito aos diferentes fatores físico-químicos avaliados sob diferentes condições de armazenamento. A análise reológica mostrou que as formulações apresentaram comportamento pseudo-plástico sob contínuo estresse de cisalhamento. Os resultados dos testes in vivo e in vitro sobre a proteção da pele revelaram que a formulação ativa promoveu efeitos comparáveis à formulação controle. Nossos dados mostraram que emulsões múltiplas estáveis poderiam ser escolhas promissoras para a aplicação tópica do chá verde. Entretanto, a fórmula das emulsões múltiplas apresentadas neste estudo precisam ser melhoradas no que diz respeito ao pH, condutividade e viscosidade aparente. Complex multiple emulsions have an excellent ability to fill large volumes of functional cosmetic agents. This study was aimed to encapsulate large volume of green tea in classical multiple emulsion and to compare its stability with a multiple emulsion without green tea extract. Multiple emulsions were developed using Cetyl dimethicone copolyol as lipophilic emulsifier and classic polysorbate-80 as hydrophilic emulsifier. Multiple emulsions were evaluated for various physicochemical aspects like conductivity, pH, microscopic analysis, rheology and these characteristics were followed for a period of 30 days in different storage conditions. In vitro and in vivo skin protection tests were also performed for both kinds of multiple emulsions i.e. with active (MeA) and without active (MeB). Both formulations showed comparable characteristics regarding various physicochemical characteristics in different storage conditions. Rheological analysis showed that formulations showed pseudo plastic behavior upon continuous shear stress. Results of in vitro and in vivo skin protection data have revealed that the active formulation has comparable skin protection effects to that of control formulation. It was presumed that stable multiple emulsions could be a promising choice for topical application of green tea but multiple emulsions presented in this study need improvement in the formula, concluded on the basis of pH, conductivity and apparent viscosity data.

9 páginas, 2 figuras, 1 tabla, [ES] La continua aparición de evidencias científicas acerca del papel de la dieta y/o sus componentes en el bienestar y la salud, ha favorecido la aparición de los alimentos funcionales que en el actualidad constituyen uno de los principales impulsores del desarrollo de nuevos productos. La aplicación de emulsiones múltiples abre nuevas posibilidades en el diseño y desarrollo de alimentos funcionales. Tales sistemas pueden emplearse como producto intermedio (ingrediente alimentario) dentro de las estrategias tecnológicas habitualmente empleadas en la optimización de la presencia de compuestos bioáctivos en alimentos más saludables y funcionales. Este artículo presenta un breva análisis de los tipos, características y formación de emulsiones múltiples, posibilidad de localización de compuestos bioactivos, así como su potencial aplicación en el diseño y preparación de alimentos saludables y funcionales. Tales aplicaciones se manifiestan especialmente relevantes en relación con aspectos cuantitativos y cualitativos del material lipídico (reducción de grasa/calorías y optimización del perfil de ácidos grasos) encapsulamiento de compuestos bioactivos fundamentalmente hidrofílicos y reducción de sodio. Esta estrategia ofrece interesantes posibilidades en relación con el enmascaramiento de sabores y mejora de las propiedades sensoriales de los alimentos, [EN] 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., A los proyectos AGL2011-29644 y Consolider-Ingenio 2010:CARNISENUSA (CSD2007-00016) del Plan Nacional de I+D+i

The effect of storage temperature (65°C, 48 hours) on the oxidative stability of a food-grade water-in-oil-in-water (W/O/W) emulsion was studied by comparison with an oil-in-water (O/W) emulsion. The emulsions were prepared with linseed oil or olive oil, and in each case, two antioxidants were evaluated, an aqueous Melissa lyophilized extract and BHA. Emulsions were characterized using brightfield light microscopy and the oxidation was monitored by measuring the lipid hydroperoxides, thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and trienes (CT), alpha-tocopherol and Lipophilic Oxygen Radical Absorbance Capacity (L-ORACFL) Assay. A great stability of olive oil emulsions was observed, without noticing differences between antioxidants or type of emulsion. This behaviour was not observed in linseed oil emulsions. In this case the lipophilic antioxidant (BHA) seemed to be more efficient delaying the lipid oxidation in W/O/W emulsions than the water Melissa extract while the opposite occurs in the O/W emulsion. The type of antioxidant is a key factor in controlling oxidation in W/O/W and O/W emulsions which are prepared with highly polyunsaturated oils, but not in the case of highly monounsaturated ones.

Trabalho apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas As nanopartículas lipídicas como as nanopartículas de lipídeos sólidos (SLN, Solid lipid nanoparticles) baseadas em emulsões múltiplas são novos sistemas terapêuticos versáteis e inovadores para a incorporação de fármacos hidrófilos. O presente estudo reporta um desenho fatorial 33 com o objetivo de desenvolver uma formulação de SLN ótima. As variáveis independentes analisadas foram as concentrações de lipídeo sólido, agente tensioativo hidrófilo e lipófilo. O tamanho hidrodinâmico de partícula, o índice de polidispersão e o potencial zeta foram as variáveis dependentes. O estudo através do desenho fatorial aplicado, permitiu otimizar uma formulação de SLN que é composta por 1.0%(m/m) de lipídeo sólido, 0.25%(m/m) de agente tensioativo lipófilo e 1.5%(m/m) de agente tensioativo hidrófilo. Com o objetivo de aumentar o potencial zeta das partículas, e consequentemente a sua estabilidade, recorreu-se ao uso do alginato de sódio como polímero de revestimento. Para o efeito foram testadas 4 concentrações diferentes (0.25%, 0.5%, 0.75% e 1.0% (m/m), sugerindo que a concentração ideal testada foi 0.75% (m/m). A influência do pH na fase aquosa interna das SLN também foi testada e os resultados sugerem que pH baixos (i.e., 2-3) influenciam fortemente o tamanho hidrodinâmico das partículas produzidas, aumentando da região nano para micro. Contudo, as SLN podem revelar-se úteis na incorporação de fármacos hidrófilos que requerem pH entre 4-10. As SLN baseadas em múltiplas emulsões são uma abordagem promissora para a incorporação de fármacos hidrófilos, e também para proteínas e péptidos. Lipid nanoparticles, namely solid lipid nanoparticles (SLN) based on multiple emulsions are versatile and innovative carriers for hydrophilic biomolecules. This work reports a 33 full factorial design study to optimize SLN formulations enclosing hydrophilic biomolecules in an inner aqueous phase. The concentrations of solid lipid, lipophilic and hydrophilic emulsifiers were set as the 3 independent variables. Mean particle size, polydispersity index and zeta potential were set as the dependent variables. The selected optimized parameters were set as 1.0%wt of solid lipid, 0.25%wt of lipophilic emulsifier and 1.5%wt of hydrophilic emulsifier. The coating of SLN with sodium alginate was found to improve the PZ of the lipid particles and four different concentrations were evaluated (0.25; 0.5; 0.75 and 1.0% wt). The results suggested that the ideal concentration was 0.75%wt. The influence of low pH (i.e. about 2-3) in the inner aqueous phase was stronger than the higher pH values, contributing for the production of larger droplet sizes. Nevertheless, these systems can be useful for the incorporation of biomolecules requiring a pH ranging between 4 and 10. SLN based on multiple emulsions technology were found to be a promising approach for the incorporation of several hydrophilic drugs, such as proteins and peptides.

Background and the purpose of the study Lamotrigine is a broad spectrum anticonvulsant drug widely used as mono- or adjunct- therapy in adults and children. The aim of this study was to develop controlled release liquid formulation of lamotrigine to improve bioavailability and compliance of pediatric and geriatric epileptic patients. Methods Multiple (w/o/w) emulsion was prepared using one step emulsification technique. It was evaluated for entrapment efficiency (EE), morphology, zeta potential (ZP), polydispersity index (PI), rheology, thermal property, in vitro drug release behavior and stability. In vivo studies in albino mice were carried out using maximal electroshock seizure (MES) test and strychnine induced seizure (SIS) pattern test and results were compared with marketed formulation. Results The EE of the formulations varied from 84.37% to 98.11%. The ZP and PI values of the prepared batches were in the range of +23.46 to +28.07 and 0.256 and 0.365, respectively. Microscopic observation clearly indicated the stability of the emulsions during the storage period. All batches exhibited controlled in vitro drug release up to 12 hrs. Batch C11 exhibited significantly longer duration of protection of seizure in mice against MES and exhibited comparable efficacy in SIS as compared to the marketed formulation. Major Conclusion Multiple emulsion of lamotrigine compared to the marketed tablet showed plasma drug concentration within therapeutic range for longer time and comparable efficacy.

The purpose of this work was to investigate the effect of FGF 2 and TGF-β1 on the early steps of dentin regeneration using microencapsulation of theses factors into a microparticles matrix to ensure growth factors protection and to provide bioactive sustained release in contact with dental pulp cells and then the application of the obtained microparticles in direct pulp capping using a culture model of entire tooth. This work involves the optimization of technical means used to achieve encapsulation of TGFβ1, FGF-2 using the poly (lactic-glycolic acid) PLGA. Physicochemical and colloidal characterization of microspheres shows that the microparticles retain their physicochemical characteristics after drying and re-suspended in water. The double emulsion method was used to separately encapsulate (FGF-2) and (TGFβ1). Microparticles morphology, loading, shelf life, potential toxicity and release kinetics were studied. Then the proliferation of dental pulp cells was examined in contact with microparticles. Biological studies show no toxic effect of particles on pulp fibroblasts. Growth factors have kept their specific biological activity. A culture model of human entire tooth was used to achieve the application of microparticles as a dental direct capping material to confirm their biological activities ex vivo. These microparticles can be useful in studies of early steps of dentin regeneration, activation and migration of progenitor cells in dental pulp; Ce travail a été mené afin d’étudier l’effet du FGF 2 et du TGF-β1 sur les étapes précoces de la régénération dentinaire en utilisant la micro-encapsulation de ces facteurs dans une matrice pour les protéger et contrôler leur libération et ensuite l’application des microparticules obtenues en coiffage pulpaire direct dans un modèle de culture de dents entières. Ce travail consiste d’abord à l’optimisation des moyens techniques mis en oeuvre pour réaliser l'encapsulation du TGFβ1, FGF-2 à l'aide de l'acide poly (lactique-glycolique) PLGA. Les études de la caractérisation colloïdal et physico chimique des microparticules montre que les microparticules gardent leurs caractéristiques physicochimiques après séchage et resuspension dans l’eau. La procèdes optimisé a été ensuite utilisé pour encapsuler les facteurs de croissance. L’encapsulation de FGF-2 et TGF-β1 a été obtenue avec une taille, une efficacité d’encapsulation et une profile de libération adaptés au type d’application choisi. Les études biologiques ne montrent aucun effet toxique des particules sur les fibroblastes pulpaires. Les facteurs de croissance ont gardé leur activité biologique spécifique. Un modèle de culture de dent entier humain a été utilisé pour réaliser l’application de nos microparticules comme un matériau de coiffage dentaire pour confirmer leurs activités biologiques ex-vivo. Ces microparticules peuvent être utiles dans les études des étapes précoces de la régénération dentinaire, l'activation et la migration des cellules progénitrices de la pulpe dentaire

WOS: 000254916000010, PubMed ID: 18166519, The purpose of the study was to see the effect of two antiaging agents in one stable multiple emulsion prepared using natural oil. Vitamin C, which is a very unstable ingredient and is decomposed in the presence of oxygen, active as an antioxidant, was entrapped in the inner aqueous phase of w/o/w multiple emulsion. In this way, slow release can be expected and the effect of vitamin C can be increased since it is protected from the external environment by entrapping it in the internal phase. The other ingredient which is a product of wheat proteins was also used as an antiaging agent in the oily phase. Both of the ingredients increase the synthesis of collagen fibers in the dermis. Therefore, a synergystic effect can be produced by using the two ingredients in one formulation. In this study, multiple emulsions were prepared by the two-step method. Basic formulation containing no active material and a stable formulation containing vitamin C in the internal aqueous phase and wheat protein in the oily phase were prepared. The oil used was macadamia nut oil since it contains a high quantity of palmitoleic acid which is the natural ingredient of the young skin. Basic formulation as well as the active formulation after confirming their stabilities, were applied to the cheeks of 11 human volunteers for four weeks. Different parameters of the skin were monitored every week to see any effect produced by these emulsions. The data obtained was evaluated statistically. It was found that the active formulation as well as base increased the moisture of the skin as verified by statistical tests. However, there were no significant variations in other parameters like skin sebum, pH, elasticity, melanin and erythema, concerning the two formulations.

新大院博（工）甲第236号

This paper describes the conditions of preparation of poly(lactide-coglycolide) microspheres with a mean diameter lower than 10 μm obtained by a (w1/o)w2 emulsion solvent evaporation method. Different parameters influencing respectively the size of the inner emulsion and the diameter of the microspheres were determined. V3 BRU, which is a specific immunogenic fraction from GP120 of HIV, was encapsulated in those microspheres. The entrapment efficiency was shown to be superior to that of microspheres prepared according to the single emulsion solvent evaporation method. Electron microscopy observations demonstrated the presence within the microspheres of globules corresponding to the w / o initial inner emulsion in which the peptide was dissolved in the aqueous phase. Analysis of the release kinetics was carried out in phosphate buffer (PBS), in artificial gastric and intestinal medium. V3 BRU release in PBS was slow, reaching a plateau at 24 h corresponding to 25% of drug release. In addition, V3 BRU was not released in gastric medium within 4 h whereas under the same time conditions, 60% of the drug was released in the presence of intestinal medium. These results open up interesting prospects for the use of these microspheres as an oral adjuvant for HIV vaccination.

N-Acetylcysteine was known to be used as a mucolytic agent having significant antioxidant activity. It has been reported to be used to alleviate or improve various cosmetic conditions and dermatological disorders including changes or damage to skin associated with intrinsic or extrinsic aging recently. However many benefits regarding to its antioxidant effects were reported, its probable potential moisturizing effects have not been stated yet. Since N-acetylcysteine has similar effects as vitamin C, it might be assumed that it could also increase skin hydration by its antioxidant capacity. The aim of this work was to investigate the feasibility of a topical delivery system as a multiple emulsion containing N-acteylcysteine and compare the moisturizing potential of this formulation with a base multiple emulsion and vitamin E which was chosen as a popular moisturizer.

Se ha demostrado que las microesferas biodegradables de ácido poli L-láctico como portadores de fármacos proporcionan una liberación controlada y mantenida del principio activo, disminuyendo los efectos colaterales que estos pueden provocar. Por este motivo, se propuso evaluar la influencia de parámetros como el rendimiento, la eficiencia de encapsulación y el diámetro medio de las partículas, en el proceso de preparación de microesferas cargadas con doxorubicina, por el método de emulsión múltiple y evaporación del solvente. Se comprobó que la concentración de alcohol polivinílico y cloruro de sodio, así como la baja temperatura en la fase acuosa externa contribuyen a lograr mejores resultados en las características físico-químicas de las microesferas obtenidas.It has been proved that the biodegradable microspheres of poly l-lactic acid as drug carriers provide a controlled and maintained release of the active principle, reducing the side effects they may cause. For this reason, it was proposed to evaluate the influence of parameters such as performance, encapsulation efficiency and mean diameter of the particles, in the process of preparation of microspheres loaded with doxorubicin by the method of multiple emulsion and evaporation of the solvent. It was proved that the concentration of polyvinyl alcohol and sodium chloride, as well as the low temperature in the external aqueous phase, contribute to attain better results in the physical and chemical characteristics of the obtained microspheres