Dissertations / Theses on the topic 'Emulsions (pharmacy)'
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Corswant, Christian von. "Lecithin-based microemulsions for pharmaceutical use phase behavior and solution structure /." Lund : Lund University, 1998. http://catalog.hathitrust.org/api/volumes/oclc/68945035.html.
Full textPozo, Carrascosa Alfonso del. "Aplicación de la conductimetría al estudio de emulsiones: parámetros conductimétricos en emulsiones fluidas O-A elaboradas con emulgentes no iónicos." Doctoral thesis, Universitat de Barcelona, 1985. http://hdl.handle.net/10803/673132.
Full textGraf, Anja, and n/a. "Preparation and physico-chemical characterisation of microemulsion-based nanoparticles." University of Otago. School of Pharmacy, 2008. http://adt.otago.ac.nz./public/adt-NZDU20080701.121440.
Full textJohnson, Olufunmilayo Lily. "The formulation of bio-compatible perfluorocarbon emulsions." Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315115.
Full textBeldengrün, Yoran. "Water-in-Water Emulsions for Obtaining Enzyme-Loaded Microgels and Encapsulated Emulsions." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/662970.
Full textHoms, Maria. "Estudi de la formació de nano-emulsions per mètodes de baixa energia." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/396651.
Full textIn the present thesis the formation of oil in water (O/W) nano-emulsions by low-energy methods have been studied to investigate the mechanisms involved in their formation. Nano-emulsions have been prepared water content in water/nonionic surfactant/oil systems at constant temperature by a novel procedure which consists in the addition of a more hydrophilic surfactant to O/W microemulsions. Moreover, the key phases determining the properties of O/W nano-emulsions generated by addition of water to binary and ternary mixtures in water/nonionic surcatant/oil systems at constant temperature has been studied. It has been found that nano-emulsion formation in these type of systems may take place by three different mechanisms: (a) by phase inversion, (b) by dilution of O/W microemulsion without phase inversion, and (c) by phase inversion followed by dilution of O/W microemulsions. It has been also noticed that the coexistence of the system components in a single phase during the emulsification process play an important role in nano-emulsion formation and properties. The use of nano-emulsions as template to obtain nanoparticles is focusing an increasing interest. In this research the formation of polymeric nanoparticles from polymeric nano-emulsions as potential nanocarriers for biomedicine has been studied. In particular, the influence of the polymer concentration on the formation and properties of nano-emulsions and nanoparticles in aqueous medium has been investigated since this aspect has not been reported yet. O/W nano-emulsions have been formed in a water/nonionic surfactant/(PLGA in Ethylacetate) system and polymeric nanoparticles have been generated by solvent evaporation method. An active molecule, dexamethasone, was successfully encapsulated and its release to a receptor solution as a function of polymer content was also evaluated. The results obtained in terms of particle size, stability, encapsulation efficiency, release and citotoxicity in vitro assays, have indicated that these polymeric nanoparticles are of interest for biomedical applications.
San, Miguel Delgadillo Adriana. "Pickering emulsions as templates for smart colloidosomes." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/45760.
Full textKrauel, Karen, and n/a. "Formulation and characterisation of nanoparticles from biocompatible microemulsions." University of Otago. School of Pharmacy, 2005. http://adt.otago.ac.nz./public/adt-NZDU20070424.130711.
Full textLukoševičiūtė, Sabina. "Aliejus vandenyje (a/v) emulsinės sistemos su linų sėmenų aliejumi modeliavimas ir biofarmacinis tyrimas in vitro." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140618_215057-13575.
Full textPurpose of the research – design oil-in-water emulsion system with linseed oil and in vitro biopharmaceutical research determine system composition and drug form influence on hydrophilic agent release from o/w emulsion system. Task of the research: determine linseed oil required HLB value and design o/w emulsion system; design o/w emulsion system, when oil phase – linseed oil and study physico – chemical properties; establish emulsion system stability after 1 month by physico – chemical properties; incorporate ascorbic acid in emulsion system and investigate ascorbic acid release from emulsion system research in vitro through semi – permeable membrane. Studies showed that the required HLB of linseed oil for o/w emulsion is 7,51. Investigated emulsion systems, which oil phase was 20%, 30%, 50% and 60% linseed oil, aqueous phase – purified water, 0,5% and 1% chitosan solution also emulsifiers span 80 and tween 80 concentration was 20% by weight of the oil phase. It is established that linseed oil and chitosan solution also increase emulsions viscosity and delay emulsions creaming. Also chitosan solution increase emulsions acidity, stabilizes them and provide desired acid pH for dermatological preparations. Desighed and selected o/w emulsion system, which oil phase is 50% linseed oil, aqueous phase 1% chitosan solution according to microstucture, viscosity and pH value. This emulsion stayed stable during 1 month storage. Studies also showed that hydrophilic agent – ascorbic... [to full text]
Pi, i. Boleda Berta. "Desenvolupament i recerca de formulacions per a vacunes veterinàries." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/668481.
Full textINTRODUCTION: This thesis is the result of a collaboration between Universitat de Barcelona and a private company called Laboratoris Hipra, S.A. Veterinary companies suffer serious economic losses because of diseases such as swine fever. In order to prevent and treat them, veterinary industry makes use of vaccines, for example, in emulsion form. The development of emulsions is not an easy task because emulsions may present stability problems and incompatibility with the antigens selected therefor. AIM: To obtain stable and robust emulsions, which are compatible with the selected antigens. On the one hand, the first specific aim is to replace the natural thickener thickener A present in a commercial o/w emulsion, to avoid viscosity variability depending on thickener batches. On the other hand, the second specific aim is to replace the oil phase present in a commercial w/o vaccine of an unknown composition by a new oil phase. EXPERIMENTAL METHODS: Since emulsions are multifactorial systems, all the trials were planned using experimental design methodology. RESULTS AND DISCUSSION: Regarding the o/w emulsion aim, the substitution of Thickener A by other thickeners was unsuccessfully tested. After many different tests, a stable emulsion comprising Thickener D' and Thickener F as thickeners was obtained. However, this formulation presented variability depending on the batch of Espessant F. This problem was solved by a previous activation of Thickener F. Finally, the definitive formulation with activated Thickener F passed correctly the toxicity test and stability test up to 12 months. Secondly, to develop a w/o emulsion with low viscosity and stable more than 24 hours was a though process. But finally, as a result of many trials combining different oils and surfactants, a formulation comprising ethyl oleate, Span® 80 and Kolliphor® ELP showed positive results regarding stability and viscosity up to 6 months. CONCLUSIONS: Two new emulsions were developed suitable to replace commercial vaccines keeping substantially their initial features such as viscosity, stability and toxicity.
Fernández, Campos Francisco. "Nanoemulsiones de nistatina para el tratamiento de candidiasis muco-cutáneas." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/83638.
Full textMuco-cutaneous candidosis is a common opportunistic infection must be treated to prevent other tissue invasion. Nystatin is one of the most prescribed drugs to treat this pathology, but due to its physicochemical properties its pharmaceutical-technological requirements make it a challenge. The purpose of this work was the development and characterization of an optimal nystatin delivery system for the potential treatment of oral candidosis avoiding undesirable side effects and toxicity of potential systemic absorption. Two nanoemulsion (N1 and N2) was developed, evaluated and characterized. It has been formulated successfully as a stable nanoemulsion with a droplet size of 75 and 138 nm, respectively. First order release parameters were estimated using different mathematical approaches and ex vivo permeation of nystatin through human skin and porcine buccal mucosa were found no systemic effects would happen. Microbiologic studies performed revealed an enhanced antifungal effect of the nystatin loaded nanoemulsion. Also the evaluation of buccal mucosa ultrastructure by transmission electron microscopy methodology showing a harmless effect in the mucosa microstructure. We can infer that the selected nystatin nanoemulsion could be potentially used on candidosis infection under mucositis conditions.
Leitner, Stefanie. "Design of multifunctional polymeric nanoparticles for biomedical applications." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/131464.
Full textEl objetivo general de esta investigación fue el diseño de nanopartículas poliméricas catiónicas, a partir de nano-emulsiones obtenidas por métodos de baja energía, para aplicaciones biomédicas. Este objetivo incluye la preparación de nano-emulsiones catiónicas de tipo aceite en agua (O/W) con métodos de baja energía y su caracterización, la preparación y caracterización de nanopartículas poliméricas catiónicas utilizando los O/W nano-emulsiones catiónicas como plantilla, la funcionalización de las nanopartículas poliméricas y estudios in vitro de las nanopartículas funcionalizadas. Se han obtenido nanopartículas catiónicas poliméricas a partir de nano-emulsiones, utilizando un polímero preformado que era incorporado en la fase oleosa. Se confirmó la posibilidad de formar complejos entre nanopartículas seleccionadas y compuestos bioactivos, tales como ácido fólico y oligonucleótido antisentido (ASO) fosforotioato. Las características (tamaño y carga superficial) de las nanopartículas y de los complejos formados con ácido fólico o ASO se hallan en un rango que permitiría su aplicación como agentes terapéuticos. Los estudios in vitro de nanopartículas y de los complejos de nanopartículas: oligonucleótido revelaron que las nanopartículas, a concentraciones iguales o inferiores a 3 mM no son tóxicas para las células HeLa, que la concentración de especies catiónicas de las nanoparticluas debe ser baja para obtener valores bajos de hemólisis y que la presencia de ácido fólico unido a las nanopartículas contribuye a la obtención de valores bajos de hemólisis. Además, los complejos de nanopartícula: oligonucleótido mostraron una inhibición de genes en ausencia de suero bovino fetal (FBS), por lo que son candidatos prometedores para la inhibición de genes in vitro. Sin embargo, en presencia de proteínas del suero, no se detectó silenciamiento génico, lo que limita el uso de estas nanopartículas para experimentos in vivo. No obstante, con una funcionalización adecuada (por ej. con CPP) posiblemente se podría favorecer la penetración celular y por tanto conseguir transfección.
Sosa, Díaz Lilian Elisa. "Elaboración de formulaciones nanoestructuradas de Anfotericina B para el tratamiento de la Candidiasis, Aspergilosis y Leishmaniosis cutánea." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/665551.
Full textThe skin constitutes one of the first lines of defense of our organism and, as such, it can suffer the aggression of many microorganisms and parasites. These pathologies include the mycosis and leishmaniosis that can be treated with a variety of drugs presented under different pharmaceutical forms designed for the corresponding routes of administration, the most common oral, cutaneous and parenteral pathways. For the treatment of skin conditions and their annexes, the skin route in principle is the one of choice, however, in some cases it does not provide the expected therapeutic results, often due to poor penetration and / or retention of the drug at the dermal level. This lack of efficiency could be mitigated by the use of vehicles such as nanoemulsions and thermorreversible hydrogels, giving rise to new formulations that could be used as an alternative to oral or parenteral administration medications for the treatment of cutaneous pathologies. Amphotericin B may be a good candidate, given its oral nephrotoxic potential and the absence in Europe of medications with this active ingredient for its skin administration. If these new formulations were viable, they would be a good alternative, since in principle the potential undesirable effects of the drug would be considerably reduced. In addition, compared with injectables, they would present the benefit of non-invasive and painless administration. For the development of the Thesis, a comprehensive preliminary bibliography study has been carried out which is summarized in Chapter 1 of the report. Next, in Chapter 2, the objectives and established work plan are set out. The other chapters deal with the experimental part with its final conclusions.
Arias, Chousa Eva María. "Desarrollo de formulaciones innovadoras para la liberación de principios activos en la piel." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/666662.
Full textEspinoza, Tituana Lupe Carolina. "Estrategias terapéuticas basadas en micro y nanoemulsiones para el tratamiento del Alzheimer y enfermedades inflamatorias de la piel." Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/671419.
Full textSuñer, i. Carbó Joaquim. "Estudi galènic i biofarmacèutic d’emulsions múltiples de clotrimazol, econazol i bifonazol d’aplicació tòpica." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/404278.
Full textThe treatments of superficial mycoses are made primarily with antifungal topical administration, although sometimes it may be necessary to use systemic antifungals. The topical treatment has the potential to achieve high concentrations of the drug in the affected area of the skin with minimal exposure to other organs. This can greatly increase the efficacy and safety in relation to systemic administration. However, the indicated treatment should always be individualized according to patient characteristics and the injuries. The administration vehicle for each type of fungal infection, must choosen properly, to ensure satisfactory results in every situation. Antifungal drugs are classified, among others, according to their chemical properties. Azolic derivatives (lanosterol 14-α-demethylase inhibitor) constitute one of the most representative of the current therapies for the treatment of superficial fungal and/or epidermal infections. Among them are: clotrimazole (CLT), bifonazole (BFZ), econazole (ECN). Once reviewed the recent literature in the field of dispersed multiple emulsions systems types, basic formulations currently recommended for topical application on the skin are proposed. In these formulations proposed convey different antifungal agents, the physicochemical characteristics are evaluated and finally the skin penetration and permeation of the preparations are studied. As the first disadvantage of the emulsions is their instability, in the current work, the incidence of the components of these formulations on stability according to the physico-chemical is first studied, and secondly the practical feasibility of the formulations studied by the drug penetration, skin permeation and antimicrobial efficacy is justified.
Wisch, Michael Henry. "Microemulsions : a new perspective in the treatment of paediatric and geriatric tuberculosis patients." Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1003283.
Full textAparicio, Pelegrin Rosa M. "Estudi d’incorporació i alliberament de fàrmacs amb noves formes de dosificació basades en sistemes micro-nanoestructurats." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/673925.
Full textMarín, Quintero Deiry Margot. "Emulsión lipídica inyectable de nistatina como alternativa a los tratamientos clásicos de infecciones fúngicas invasivas." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/125061.
Full textNystatin is a polyene macrolide with broad antifungal spectrum restricted to topical use owing to its toxicity upon systemic administration. The aims of this work were the design, development and optimization of Nystatin loaded lipid emulsion for intravenous administration. A closed circuit system was designed to apply ultrasound during the elaboration of the lipid intravenous emulsions. Additionally a comparison with the commercially available Intralipid® 20% was also performed. Manufacturing conditions were optimized by a factorial design. Formulations were evaluated in term of physicochemical parameters, stability, release profile and antimicrobial activity. The average droplet size, polydispersity index, zeta-potential, pH and volume distribution values ranged between 192.5 and 143.0 nm, 0.170 and 0.135, -46 and -44 mV, 7.11 and 7.53, 580 and 670 nm, respectively. The selected nystatin loaded lipid intravenous emulsion (NYS-LIE54) consisted of soybean oil (30%), soybean lecithin (2%), Solutol® HS 15 (4%) and glycerol (2.25%) was stable for at least of 60 days. In vitro drug release studies of this formulation suggested a sustained release profile. Equally, NYS-LIE54 showed the best antimicrobial activity being higher than the free drug. Thus it could be a promising drug delivery system to treat systemic fungal infections.
Fornaguera, Puigvert Cristina. "Development of multifunctional polymeric nanoparticles by nano-emulsion templating as advanced nanocarriers targeting the blood-brain barrier." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/285368.
Full textLes nanopartícules polimèriques multifuncionals (NPs) representen una alternativa prometedora pel tractament de malalties neurodegeneratives, a través de l’administració intravenosa (i.v.), ja que els tractaments actuals provoquen molts efectes secundaris. Les NPs, en canvi, si estan correctament dissenyades, poden actuar específicament en el teixit diana. Ja que l’òrgan diana és el cervell, és necessari un element de vectorització per poder creuar la barrera hemato-encefàlica (BBB). En aquest context, l’objectiu de la present tesi és l’obtenció de NPs com a sistemes avançats d’alliberament de principis actius que travessin la BBB. Es van obtenir NPs a partir de nano-emulsions (NE) plantilla, emprant l’àcid poli-(làctic-co-glicòlic) com a polímer i el mètode d’inversió de fases a temperatura constant per emulsionar, seguit d’evaporació de solvent per obtenir NPs. Les NPs obtingudes tenen mides apropiades per l’administració i.v.. Es va aconseguir encapsular un fluorescent i NPs magnètiques dins les NPs polimèriques, per fer-les servir com a sistemes d’imatge. També es van encapsular fàrmacs per usar-les com a sistemes terapèutics. En tots els casos, es van aconseguir eficiències d’encapsulació molt elevades i un alliberament del fàrmac controlat i prolongat en el temps. A més, es va aconseguir funcionalitzar la superfície de les NPs amb diferents elements. Es van unir covalentment dendrons catiònics per posteriorment unir oligonucleòtids electrostàticament. També es va afegir una coberta exterior de polietilenglicol per protegir el material genètic. Per altra banda, es va funcionalitzar la superfície de les NPs amb un anticòs específic contra el receptor de la transferrina, sobreexpressat a la BBB. A continuació, es van fer assajos in vitro, que van posar de manifest que les NPs no són citotòxiques ni hemolítiques. També es va estudiar l’eficiència de transfecció cel•lular del material genètic, arribant a eficiències de transfecció equivalents a les dels vectors comercials. Assajos in vivo van permetre confirmar el pas a través de la BBB, sobretot de les NPs funcionalitzades amb l’anticòs. Els resultats obtinguts permeten concloure que s’ha aconseguit dissenyar noves NPs polimèriques a partir de NE, apropiades per l’administració i.v. i amb capacitat de travessar la BBB.
Alvarado, Bonilla Helen Lissette. "Estudio biofarmacéutico de triterpenos pentacíclicos antiinflamatorios vehiculizados en sistemas nanoestructurados para aplicación tópica." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/301772.
Full textOleanolic acid (OA) and its isomer ursolic acid (UA), pentacyclic triterpenes are widely existing in the natural plants and are integral part of the human diet. These triterpenes are of great interest as therapeutic agents for their various pharmacological activities such as anti-inflammatory, anticarcinogenic, antioxidant, hepatoprotective, antimicrobial, among others. The main objective of this work was to design, optimize and characterize nanostructured systems such as PLGA-nanoparticles (NPs) and nanoemulsions (NEm) containing these natural (Plumeria obtusa) an synthetic triterpenoids compounds, evaluating their anti-inflammatory and cytotoxic activities for application topical (ocular and dermal). The NPs were developed by the method of solvent displacement and optimized by central composite factorial design, the selected NPs was composed of 1.0 mg/mL OA/UA, 10.0 mg/mL of P188 and aqueous phase with pH of 5.5, obtained values of particle size around 200 nm, a surface charge of -27 mV and an encapsulation between 76-78%. NEm were developed for the construction of diagrams pseudo-ternary phase, with a final composition of 20% castor oil, 20% propylene glycol, 59.80% of Smix with ratio 4:1 (47.84% of labrasol and 11.96% of transcutol-P) together with 0.2% triterpenoid mixtures presenting monophasic appearance, small droplet size (~200 nm) and polydispersity index around 0.2. The kinetic profile of mixtures encapsulated in NPs fits with Weibull function, which follows a complex release mechanism. While the release of these mixtures from NEm follow a kinetic model of the Korsmeyer-Peppas equation, with release mechanism of non-Fickian or anomalous diffusion. The corneal and dermal permeation indicates that these triterpenoids compounds tend to be retained in greater amount in the contact area than the amount permeated, being retained slightly higher in the natural mixture. Both mixes in NPs and NEm show effective inhibition of local inflammation, this effect being more pronounced in the formulations of natural mixture. The natural mixture of nanoemulsion shows anticancer activity in the murine melanoma cell line B16, since lower concentrations (5 µM) to the pure compound (30 µM). The results presented here clearly demonstrate the suitability of these colloidal systems developed for a local anti-inflammatory effect after topical administration.
Kaminskienė, Sigita. "Pusiau kietų emulsinių sistemų (v/a) modeliavimas iš natūralių medžiagų ir jų fizikocheminių, juslinių savybių tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100621_093038-32338.
Full textEmulsion-type products are frequent in dermatology because of their sleek appearance, universality and consumer acceptability. Stable emulsified semi-solid system from natural materials is relevant because it can be used in pharmacy for cosmetic and medicinal cream production. Object of the study – a semisolid emulsified system from natural materials. Purpose of the survey was to model a composition of the semisolid emulsion system (w/o) from natural materials and to test and evaluate the physicochemical characteristics and sensory properties. The objectives: to choose the optimal composition of the emulsion system (w/o) from natural ingredients according to physicochemical characteristics and physical properties; to choose the technological conditions for inserting emulsifier into semi-solid emulsion system; to compare the properties of optimal composition emulsion system with different aqueous phase and different matrix fillers; to evaluate the influence of natural conditions and -20°C temperatures to the system; to test organoleptic properties of the optimal composition semi-solid emulsion system. According to the results of the study it was found that cholesterol is a suitable emulsifier. In application of mathematical models there were formed and tested 16 emulsion system configurations. According to the criteria of pH value, viscosity, microstructure and physical properties it was selected an optimal emulsion system consisting of: 40 parts of avocado oil, 40 parts... [to full text]
Lupo, Pasin Bryshila. "Estudio de la gelificación de alginatos para encapsulación: caracterización, preparación y aplicaciones en alimentos funcionales." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/288203.
Full textFunctional foods are beginning to play a major role in what consumers eat due that the encapsulation of active compounds is being studying by the food industry. Biopolymers as the alginate has been one of the most widely used in encapsulation due to the matrix forms a versatile, biocompatible and nontoxic barrier for the protection of those components sensitive to the factors which are exposed to foods during processing and storage. The structure of the sodium alginate used suggests a balanced contribution of their monomers with a heterogeneous distribution block that provides greater flexibility to the gel formed. Gels of calcium alginate are formed by external gelation (GE) and internal gelation (GI) mechanism using polyvalent cations, such as Ca+2. The viscoelastic properties of the gels obtained, in general, show that an increase in [Ca+2] provides more compact gels. The differences observed between their properties indicate an influence of the source of calcium by using GI and by the gelation mechanism when the GE is used. The size distribution of the microspheres obtained by GI from different emulsions and calcium citrate indicate that the microspheres with smaller size and polydispersity occur with the polyglycerol polyricinoleate emulsifier. By encapsulating the cocoa extract rich in polyphenols in the microspheres, the experimental design shows that the amount of dispersed phase significantly affects the percentage of polyphenols retained and that the stirring speed influences the mean diameter and the polydispersity of the microspheres. Moreover, the beads obtained by extrusion are affected by increased of [Ca+2] which cause a decrease in its diameter, the morphology of these confirms an influence of the type of gelation, where the spheres obtained by GE are heterogeneous, while those formed by GI are more homogeneous. For all formulations of the spheres prepared, the beads formed by GI are presented softer and less gummy respect to those obtained by GE. The incorporation of those beads also with a high cocoa extract and [Ca+2] contents into a food product such as the gelatin shows through a sensory evaluation that the astringent and bitter flavor of the natural extract is successfully masked.
Žilius, Modestas. "Propolio emulsinio (vanduo aliejuje) kremo sudėties parinkimas, įvertinant fizikines-chemines savybes." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080616_100456-54056.
Full textAt first sight cutaneous therapeutics seems simple, but the formulation of semi-solid preparations for cutaneous application are reasonable scientifically. It‘s one of the most complicated technological aspects. The choice of basis is one the most important tasks, produced semi-solid preparations for cutaneous application. It‘s possible to suppose a stability of semi-solid preparation during storage time, supported the rheologicals (value of viscosity) researches. It‘s topical to produce the basis of the cream from such components, that would be possible to avoid the long heating process, appreciated a complication of the manufacture of creams and particularly an insertion of softs extracts to the basis problems. The aim of the work is a choice of the composition of propolis emulsion (water in oil) cream, appreciated the physico-chemical properties. A composition of basis of w/o cream (mixture of liquid paraffin and polyethylene, mixture of isopropyl palmitate and polyglycerine ester, glycerine and water) was selected and the technology for manufacture of stable w/o emulsion was fitted, supported a literature and the researches of physico-chemical properties. The results of the researches showed that the optimal concentration of soft extracts of propolis, which is possible to insert to the choiced emulsion basis is 1%. The viscosity varied no more 29%, compared with the viscosity of other propolis creams. The value of cream pH is close to a skin pH. The cream remains stable... [to full text]
Yu, Shan-Chen. "Emulsions simples et multiples stabilisées par des cyclodextrines naturelles." Paris 11, 2002. http://www.theses.fr/2002PA114816.
Full textKapočiūtė, Aistė. "Nejonogeninių paviršinio aktyvumo medžiagų įtaką emulsijos (a/v) stabilumui." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140618_220044-67446.
Full textThesis goal - to explore impact of polyethylene glycol sorbitan monolaurate, sorbitan monopalmitate, polyethylene sorbitan tristearate and sorbitan trioleate to stability of direct (oil/water) emulsion of alkyl acrylate crosspolymer. Thesis object – emulsion, made with 0,6% concentration of Alkyl Crosspolymer; non-ionogenic surfactants: polyoxyethylene (20) sorbitan monolaurate, sorbitan monopalmitate, polyoxyethylene (20) sorbitan tristearate, sorbitan trioleate. Thesis objectives – To analyse sources of literary about the effects of non-iogenic surfactants on the stability of emulsion with alkyl acrylate crosspolymer; influence of non-ionogenic surfactants to size of emulsion droplets and viscosity; influence of non-ionogenic surfactants to physical stability of emulsion during centrifugation test and heating-cooling cycle; influence of conditional atmosphere to size of emulsion droplets and stability. The analysis of literary sources revealed that even a small concentration of Alkyl Crosspolymer (0.2–0.8%) has good emulsion properties, when combined with non-ionogenic surfactants. Data on the interaction of this polymer with polyoxyethylene (20) sorbitan trioleate (Tween 85) has been found; however, objects studied in this thesis have not been explored before, thus it is relevant to analyze the effects of non-iogenic surfactants on the stability of emulsion with alkyl acrylate crosspolymer. The obtained results showed that the analyzed non-ionogenic surfactants influence... [to full text]
Dougall, Paul W. R. "Investigation into the effect of formulation on intravenous lipid emulsion metabolism using a novel in vitro fluorescent assay." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33733/.
Full textRabinovich-Guilatt, Laura. "Emulsions cationiques : de la caractérisation physicochimique à leur application dans la vectorisation oculaire." Paris 11, 2005. http://www.theses.fr/2005PA114827.
Full textIn this thesis, we have studied cationic emulsions containing oleylamine (OA) which are developed for ocular delivery. In a first study we focused in the physicochemical aspects of the droplet surface, studying the OA distribution within the droplet and finding a basic surface pH. We developed then an analytical method which allowed us to evaluate the impact of this alkaline surface on phospholipids hydrolysis. Using this and other techniques, we evaluated the stability of the emulsions during accelerated storage conditions. Finally, the emulsions successfully delivered cyclosporine A when injected intravitreally in an animal model of ocular inflammation
Tedajo, Gilberte-Muriel. "Emulsions multiples de type H/L/H : des véhicules prometteurs pour l'administration d'antiseptiques par voie vaginale." Paris 11, 2002. http://www.theses.fr/2002PA114811.
Full textQuintero, Carlos Gerardo. "Comportement rhéologique et propriétés interfaciales des systèmes émulsionnés d'intérêt industriel : cas des émulsions pétrolières E/H." Paris 11, 2008. http://www.theses.fr/2008PA114835.
Full textRheological properties of crude oil-in-water emulsions studied, as well as the properties of the interface. Viscoelastic, plastic and flow behavior was studied. Viscosity as a function of phase ratio provides an exponential trend (Richardson’s Law). Crude oil has a very different rheological behaviour at temperatures upper or lower than 23°C, corresponding to paraffin’s precipitation point. The properties of concentrated emulsions can be modeled according Princen’s theories. The rheological behavior of the interface was characterized through measurements of the viscoelastic properties, using a drop oscillating rheometer. It was verified the formation of a gel at the interface according to the Law of Winter and Chambon. The crude oil composition and the volume fraction of the dispersed phase are very important factors to describe the rheological properties of these emulsions
Dupuis, Laurent. "Emulsions multiples en cosmétique : caractérisation de l'influence de l'encapsulation sur les cinétique d'action validation sur un modéle cutané ex vivo." Reims, 1996. http://www.theses.fr/1996REIMP203.
Full textPetraitytė, Jūratė. "Puskietės emulsinės sistemos v/a su bičių vašku modeliavimas ir kokybės vertinimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140630_133347-17992.
Full textEmulsion has an attractive conformation and is an universal product. It‘s usage is simple and acceptable. For this reason, it is often used in dermatology for curing different skin disease. Stable semisolid emulsion base from natural materials is relevant because it has a big variety of use in cosmetic and remedial cream production. The object of research – the system of semisolid emulsion water in oil from natural materials and beeswax as a carrier of medical materials in dermatological preparations. The aim of the work – modeling the system of semisolid emulsion water in oil with the beeswax and modeling materials as liberation ascorbic acid from simulated system and it‘s biopharmacy evaluation by in vitro research. The task of research: to choose the composition of semisolid emulsion system on the ground of orthogonal statistic plan and select stable samples according to evaluation criterion (the proper pH, viscosity, microstructure and organoleptic properties); to rate physicochemical rates of the system of semisolid emulsion (pH, viscosity, microstructure) and evaluate their stability after 1 and 3 months; to evaluate the influence of beeswax on the viscosity, stability, sensual properties and the liberation of ascorbic acid from the system of semisolid emulsion; to evaluate modeling materials – the liberation of ascorbic acid from investigative system of semisolid emulsion carrying out biopharmacy research in vitro through semi-permeable membrane; to evaluate sensual... [to full text]
Djedour, Amel Safia. "Etude et caractérisation d'un nouveau polymère thermosensible : application à la formulation d'émulsions multiples sensibles au cisaillement par thermogélification." Paris 11, 2007. http://www.theses.fr/2007PA114815.
Full textA new multiple emulsion W/O/W stabilized by a thermosensitive polymer was prepared, allowing the preparation of fluid emulsion at ambient temperature, which gels when used (topical use). A new polymer was used, EG56®, which gels at low concentration and is weakly shear-thinning. The replacement of Abil® EM90 by Emulsifier 10 increases the release rates. The study of the interfacial rheology of the films allows the understanding of the healing phenomenon. The influence of the aqueous globules diameters on the release rates was also studied. The results show that the line of fracture of the globule passes by the less resistant way, crossing by the globule when it is large-sized, or by-passing it to get through the oily phase, when it is smaller. These results bring to light the complexity of the mechanisms of break up of the multiple globules, with the importance of the rheological interfacial and the adsorption properties of the lipophilic surfactant used, and the influence of the size of the internal aqueous globules on the release under shear
Beladjine, Mohamed. "Co-encapsulation d'un agent immunosuppresseur et d'un agent anti-inflammatoire dans une émulsion de Pickering pour le traitement topique de pathologies cutanées." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS514.
Full textIn this thesis work, we formulated innovative Pickering emulsions, stabilized by biocompatible and biodegradable poly (lactic-co-glycolic acid) nanoparticles (NP), using Miglyol as the oil phase. These systems could be an alternative to conventional emulsions, often stabilized with synthetic surfactants that can be responsible for irritation in particular during long-term topical treatments. Two active pharmaceutical ingredients (API) were successfully co-encapsulated, the first one, an immunosuppressant agent, entrapped in PLGA NP, the second one, an anti-inflammatory agent, incorporated in Miglyol droplets.Firstly, a thorough physicochemical characterization allowed to better understand the stabilization mechanism of these emulsions, depending on the type of NP used. Moreover, the influence of the addition of API was evaluated on the macroscopic, microscopic and interfacial structures of the emulsions, also on their stability. Secondly, we demonstrated that the addition of Carbopol, a thickening agent, improved the stability, texture and pH of emulsions. Finally, the therapeutic potential of such system was investigated through preliminary evaluation of its cytotoxicity on keratinocyte cells, but also its immunosuppressive activity on activated immune cells and their cytokine production. Such a system could be interesting for the treatment of chronical skin diseases
Pakalniškytė, Kristina. "Faktorių, įtakojančių tiesioginio tipo emulsijos su poliakrilo rūgšties polimeru Pemulen TR-1 stabilumą, tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130625_142131-15437.
Full textThesis goal - to investigate influence of variuos factors to stability of emulsion with hydrophilic polymer of poly acrylic acid Pemulen TR-1. Thesis object – polymeric dispersion of Pemulen TR-1; emulsion (o/w) made with polymeric emulsifier Pemulen TR-1. Thesis objectives: to study influence of concentration of water dispersion and lipophilic phase on pH value; influence of neutralizers (sodium hydroxide and trolamine) to size of emulsion droplets and viscosity; influence of polymer concentration to physical stability of emulsion during centrifugation test and heating-cooling cycle; viscosity change dependance of poly acrylic acid polymer on the emulsion pH range; influence on size of emulsion droplets and viscosity by polymeric emulsifier and non ionic to surface active agent; to evaluate surface active agnet influence on emulsifier‘s stability; to evaluate polioxietilen(20)- sorbitan trioleate influence on emulsifier‘s tixotropic features. After investigating pH meanings of water polymeric dispersion it was noticed, that increasing concentration of polymer (0.2%-0.6%) pH value dicreases (aproximately 11 %, p<0.05). Exploring influence of concentration of lipophilic phase on pH meaning it was stated that its change does not have important influence on pH value. It was noticed, that increasing concentration of polymer emulsifier viscosity of water polymeric dispersion increases accordingly. After reserching viscosity of emulsion the results were as follows that... [to full text]
Lelevičienė, Kristina. "Klampą reguliuojančių medžiagų įtaka emulsijų sedimentaciniam ir agregatiniam stabilumui." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140618_215006-96016.
Full textWhile comparing the properties of viscosity modifiers it was established that with an increase in concentration of hydroxypropyl starch phosphate the time of swelling extends on condition p<0,05, because of that to reduce the time its beter to choose acrylates/steareth-20 itaconate copolymer, which is in liquid state or polyethylene glycol hydroxy propyl hydroxyethyl ethyl cellulose polymer, which swells noticeably faster. It was observed that glycerol does not make an impact on the time thickeners swel, but the product is influenced by the temperature of swelling and the production method. To produce high-viscosity product viscosity modifiers should be soak in water at room temperature and homogenized device called "Unguator". It was observed that in order to reach 8.45 ± 0.02 Pa*s viscosity you would need 6 % of hydroxypropyl starch phosphate, while others viscosity regulators would make it with percentage 0,2-2%. Emulsion bases together with viscosity modifiers, which were used in the research, prevent droplet aggregation after formation and remained stable for 14 days and didn‘t split into layers during the centrifuge test (thereby increasing long-term stability). In microskopic test it was revealed that the smallest difference in the particle size of emulsions is the base 6% hydroxypropyl starch phosphate (1,1 μm). For the purposes of analyzing the texture is established that the hardest and the most viscous base was produced using an acrylates/steareth-20 itaconate... [to full text]
Courrier, Hélène Margaret. "Emulsions inverses de fluorocarbure destinées à l'administration de principes actifs par la voie pulmonaire : études physicochimiques et évaluations biologiques de tensioactifs fluorés dérivés du dimorpholinophosphate." Strasbourg 1, 2002. http://www.theses.fr/2002STR14175.
Full textFluorocarbons- Reverse emulsion- Fluorinated surfactant- Lung drug delivery- Langmuir Monolayer- CytototoxicityFluorocarbons (FC) and particularly perfluorooctyl bromide (PFOB) are used in liquid ventilation for the treatment of respiratory distress syndrome (RDS). Stable reverse water-in-FC emulsions incorporating a drug in their aqueous phase were developed to deliver drugs in the systemic circulation via the lungs and to oxygenate the pulmonary tissues. The pulmonary physiology, the different lung drug carriers and the fluorocarbons biomedical applications were first presented. A series of semi-fluorinated amphiphiles derived from the dimorpholinophosphate polar head group (FnHmDMP with n = 4, 6, 8 or 10 et m = 2, 5 or 11) were synthesized. The hydrocarbonated spacer influenced the surfactant adsorption process at the water/PFOB interface. F8H11DMP was the best emulsifier and allowed the preparation of reverse emulsified systems (emulsions and microemulsions) whom mean diameter are comprised between 1æm and 10 nm. The major degradation process of water-in-PFOB miniemulsions (D<180 nm after 200 days) is the molecular diffusion. The microemulsion fused with a dipalmitoylphosphatidylcholine (DPPC) monolayer (used as a simplified model of the pulmonary surface) indicating that the emulsion would facilitate the delivery of the incorporated drug. F8H11DMP and PFOB facilitate the spreading of DPPC. DPPC/F8H11DMP mix could form a new lung surfactant substitute for the treatment of RDS. Among the FnHmDMP series, the less cytotoxic surfactants were those which possessed the longest hydrophobic tail (FnHm) and the longest fluorinated chains (F8H11DMP and F10H11DMP). Administrated by intranasal route to mice, those emulsions didn't alter the lungs and didn't induced lung inflammatory reactions, but they induced a body weight decrease which was found to be reversible. The lung delivery system potential of the reverse water-in-FC emulsions was finally demonstrated by the hypoglycemic effect of the insulin incorporated in those emulsions
Noé, Catherine. "Contribution à l'étude de la fabrication et de la stabilité d'émulsions-gels à base de Pemulen R." Paris 5, 1995. http://www.theses.fr/1995PA05P212.
Full textAlbert, Claire. "Émulsions de Pickering biodégradables stabilisées par des nanoparticules de poly(acide lactique-co-glycolique) : étude physico-chimique et potentialité pharmaceutique." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS491.
Full textIn this thesis work, we formulated stable, biodegradable and biocompatible Pickering emulsions stabilized with nanoparticles (NPs) of poly(lactic-co-glycolic acid) (PLGA). Such emulsions are an alternative, potentially less toxic and irritating, to conventional emulsions stabilized with surfactants. Firstly, a thorough physico-chemical study of these systems was conducted in order to clarify their structures (macroscopic, microscopic and interfacial) as well as their mechanisms and kinetics of stabilization. Studies of the contribution of the polymer stabilizing the NPs and of the characteristics of the PLGA polymer on the properties of the emulsions were also carried out. This enabled a better identification of the physico-chemical key parameters responsible for a good stabilization. Secondly, we focused on the pharmaceutical potential of these emulsions for a topical application. Pharmaceutical active ingredients (API), used for the treatment of psoriasis, were successfully encapsulated in the NPs (cyclosporine A and tacrolimus) and the emulsion droplets (calcitriol). This study is a first step towards the use of these emulsions for the co-encapsulation of two API: one in the NPs and a second in the oil droplets. The co-encapsulation should improve patient compliance and could lead to a synergistic effect between the two API
Grandjon, Vincent. "Optimisation de la formulation galénique en vue de limiter la quantité de conservateur dans les produits topiques." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1B004.
Full textNowadays, preservatives in personal care are obviously a current issue. The aim of this study was to find out rules for molecular design and formulation conception dealing with a physico-chemistry point of view, in order to avoid classic preservatives. We have studied on structural features for antimicrobial activity and their behaviors in direct emulsions. After studies of various structural families, and a wide QSAR analysis, the result was that molecule with one or two alcohol groups are among the better antimicrobial agents. Especially, we focus on some characteristics, which improve considerably the antimicrobial activity : an asymmetric structure ; a two-hydroxylated polar head like diols or monoglycerids ; the main hydrocarbon tail should contain between 6 and 12 carbons with an optimum between 7 and 10 ; with these characteristics, the HLB value must be located between 7 and 11. An unsaturated bond in a linear chain or a β-hydroxylated group leads to an increase of decontamination. The impact of the formulation in direct emulsions of a model molecule, glycerol octanoate/decanoate, seemed to show that hydrophilic surfactants trap in their micelles the active product, which induces a decrease of the antimicrobial activity. The hydrophilic thickness of polar heads prevents the passage of the active product beyond the micelle to the micro-organism. It is therefore recommended that the quantity of surfactant used to create and stabilize the drops of oil be reduce to a minimum. The hydrophilic thickness of polar heads may be reduced by selecting the surfactants, for example an ionic phosphate. Other parameters have been demonstrated as affecting, to a lesser extent: it is recommended polymers and micro gels are used rather than surfactants in the preparation of a texture to customize the ration antimicrobial on oil and to use preferably non-polar oil
Riachy, Philippe. "Hierarchically Porous Silica Materials for the Encapsulation of Molecules of Interest." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0013/document.
Full textThis work concerns the preparation of silica materials with hierarchical porosity for the encapsulation of molecules of interest in the field of drug delivery and as biocatalysts. In order to reach this goal, the nano-emulsions were chosen as templates for the macropores of the material because of the homogeneous and small size of the emulsion droplets (less than 100 nm). The system Remcopal 4/decane/water was investigated and the optimal conditions for which nano-emulsion is formed via the phase inversion methods were determined. Adding micelles to the nano-emulsions does not affect its stability and can form a network of mesopores organized with a hexagonal symmetry. Hybrid materials which are hierarchically porous materials where the organic phase is still present, were doped with ketoprofen to study its release, which proved to be pH sensitive. Moreover, the study of the release of ketoprofen from the meso-macroporous material indicates that it is assisted by the micelles which are solubilized in the release medium. The second objective of this work was to use these porous materials as a biocatalyst for biodiesel synthesis from colza oil. For this application it was necessary that the materials are resistant to immersion in aqueous media. The study of the hydrothermal stability shows that the calcined material has the best stability in boiling water. Moreover, the material can withstand up to 550 ° C, the structure undergoes only minor damages. We also used a dual-mesoporous silica material prepared from hydrogenated and fluorinated micelles coexisting in the same solution. Thermal and hydrothermal evaluation indicates that these materials have two different decay kinetics corresponding to each of the two matrices having different pore sizes. The immobilization of lipase Mml was studied on the meso-macroporous calcined material and the dual-mesoporous material. The adsorption isotherms were used to demonstrate that the dual-mesoporous material can encapsulate more enzymes than its meso-macroporous counterpart. On the other hand, the enzyme activity, evaluated by the transesterification reactions, is more important for the calcined meso-macroporous material
Hamoudi, Mounira Cherifa. "Évaluation d'une forme galénique à base d'alpha cyclodextrine et d'huile végétale pour l'administration par voie orale de molécules actives peu solubles dans l'eau." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA114826/document.
Full textThe general aim of this thesis was the study of the potential of beads, made of α-cyclodextrin and soybean oil, for the oral delivery of poorly water soluble drugs. We have first verified that it was possible to encapsulate in beads, active molecules (progesterone and indomethacin), other than retinoid and diazepam, with a high drug loading and a satisfying yied. The study of the behaviour of freeze-dried naked beads, in terms of stability and drug release in simulated gastro-intestinal fluids, allowed to propose a mechanism for the release of the encapsulated drug, involving several steps: i) hydration of the freeze-dried beads, ii) dissolution of α-CD hydrophilic matrix, iii) release of oily droplets containing the active drug and then of the fraction of drug dissolved in oil, following a partition phenomenon, iiii) fragmentation of the weakened beads and at last the total release of oil. The presence of bile salts in the medium accelerates both the release and the dissolved amount, by weakening the beads and reducing the partition coefficient value of the active molecule between oil and digestive medium.We have shown in vitro as well as in vivo that it is possible to modulate the release of a model drug from the same initial formulation, according to the degree of organization of the system (dry emulsion, naked beads, coated beads obtained by an additional amount of α-cyclodextrine to the preformed naked beads). In vivo studies in rats have highlighted that dry emulsion behaves as a fast release formulation, the coated beads as a sustained release formulation and the naked beads as an intermediate one. Finally, the release of the encapsulated drug can also be modulated by modifying the drying method of the beads. Compared to freeze-drying, oven-drying modifies the properties of the beads by increasing their resistance in simulated gastro-intestinal fluids and sustaining the release of the encapsulated drug
Zhao, Xiaoning. "Synthesis and applications of functional magnetic polymer beads; synthesis and mass spectrometry analysis of model peptides." Scholarly Commons, 2012. https://scholarlycommons.pacific.edu/uop_etds/156.
Full textRuffin, Émilie. "Encapsulation de la myoglobine dans des microsphères de poly(epsilon-caprolactone) : étude des paramètres de formulation et de procédé sur les propriétés des particules et sur l’intégrité protéique." Thesis, Lyon 1, 2010. http://www.theses.fr/2010LYO10052.
Full textProtein encapsulation results in several problems related to their physicochemical properties, their sensitivity to environmental conditions and operating procedures. The specific 3D structure being directly linked to their biological activity, monitoring of protein integrity is crucial to ensure the efficacy and security of formulations. In this context, the multiple emulsion method was applied to a model protein: myoglobin (Mb). The aim of this thesis was to study the encapsulation process through 3 objectives. The first was to study the influence of formulation parameters on the particle properties and the conformation of Mb. Measurements by UV/Vis. spectrometry and calculation of key absorbance ratios established a reliable and rapid method for protein monitoring. The second was to validate the pertinence and show the limits of this method by comparing it to a second one using conductimetry measurements. Finally, the particle solidification by solvent removal and the solvent exchange were studied. The process maintains the Mb native conformation in Hollow microspheres of 15μm in diameter and an encapsulation efficiency of 36% were obtained, while keeping intact the Mb native conformation. The use of high molecular weight polymer and a fast solvent removal rate are 2 parameters inducing significant protein alteration. This work paves the way for the development of O2 carriers for muscular diseases for example
"Stimuli-responsive double emulsions for transcutaneous delivery of vaccines." Tulane University, 2008.
Find full textacase@tulane.edu
"Development of a sustained-release microsphere formulation for delicate therapeutic proteins using a novel aqueous-aqueous emulsion technology." 2008. http://library.cuhk.edu.hk/record=b5896772.
Full textThesis submitted in: December 2007.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2008.
Includes bibliographical references (leaves 80-87).
Abstracts in English and Chinese.
TITLE PAGE --- p.i
ABSTRACT --- p.ii
中文摘要 --- p.v
ACKNOWLEDGEMENTS --- p.vii
TABLE OF CONTENTS --- p.viii
LIST OF FIGURES --- p.xi
LIST OF TABLES --- p.xiv
ABBREVIATIONS --- p.xv
Chapter CHAPTER 1. --- Introduction
Chapter 1.1. --- Rationale of the Study --- p.1
Chapter 1.2. --- Current technologies for formulating long-acting parenteral protein deliver system --- p.3
Chapter 1.2.1. --- Chemical Modification --- p.3
Chapter 1.2.2. --- Sustained-release formulation --- p.4
Chapter 1.2.2.1. --- Phase separation method --- p.4
Chapter 1.2.2.2. --- Solvent evaporation/extraction method --- p.5
Chapter 1.2.2.3. --- Spray drying method --- p.6
Chapter 1.2.2.4. --- Causes for protein instability --- p.6
Chapter 1.2.2.4.1. --- Water/organic solvent interface --- p.6
Chapter 1.2.2.4.2. --- Lyophilization --- p.8
Chapter 1.2.2.4.3. --- Polymer --- p.11
Chapter 1.2.2.4.4. --- Stabilizing additive --- p.13
Chapter 1.3. --- Aqueous-aqueous emulsion technology --- p.17
Chapter 1.3.1. --- Background --- p.17
Chapter 1.3.2. --- Basic Principle --- p.17
Chapter 1.3.3. --- Phase diagram --- p.18
Chapter 1.3.4. --- Formation of aqueous-aqueous emulsion --- p.19
Chapter 1.3.4.1. --- Introduction of a water-soluble charged polymer as stabilizer --- p.19
Chapter 1.3.4.2. --- Freezing-induced phase separation --- p.20
Chapter 1.3.5. --- General Protocol --- p.21
Chapter 1.3.5.1. --- Introduction of a water-soluble charged polymeric stabilizer --- p.22
Chapter 1.3.5.2. --- Freezing-induced phase separation --- p.22
Chapter 1.3.6. --- Merits and limitations of the aqueous-aqueous emulsion technology --- p.23
Chapter 1.3.7. --- Protein selection for the sustained release formulation --- p.25
Chapter 1.4. --- Aims and scope of study --- p.26
Chapter "CHAPTER 2," --- Materials and Methods
Chapter 2.1. --- Materials --- p.28
Chapter 2.1.1. --- Proteins --- p.28
Chapter 2.1.2. --- Polymers --- p.28
Chapter 2.1.3. --- Media for TF-1 Cell Culture --- p.28
Chapter 2.1.4. --- Chemicals and Solvents for Cell Proliferation Assay --- p.29
Chapter 2.1.5. --- Other Chemicals and Solvents --- p.29
Chapter 2.1.6. --- Materials for Cell Culture --- p.29
Chapter 2.1.7. --- Materials for Reagent Kits --- p.30
Chapter 2.2. --- Methods --- p.30
Chapter 2.2.1. --- Determination of the Partition Coefficients of Proteins Between PEG and Dextran --- p.30
Chapter 2.2.2. --- Preparation of Glassy Particles --- p.31
Chapter 2.2.2.1. --- Standard Stable Aqueous-aqueous Emulsion Method --- p.31
Chapter 2.2.2.2. --- Freezing-induced Phase Separation --- p.32
Chapter 2.2.3. --- Preparation of Protein-loaded and Blank Microspheres Using S-o-w Solvent Extraction Technique --- p.32
Chapter 2.2.4. --- Optical Microscopy and Scanning Electron Microscopy --- p.33
Chapter 2.2.5. --- Determination of Protein Loading --- p.34
Chapter 2.2.5.1. --- Within Dextran Particles --- p.34
Chapter 2.2.5.2. --- Within PLGA microspheres --- p.34
Chapter 2.2.6. --- Evaluation of Protein Structural Integrity and Bioactivity in Dextran Particles and PGLA Microspheres --- p.35
Chapter 2.2.7. --- In vitro Release Study --- p.36
Chapter 2.2.8. --- RhIFN Stability Determination under Simulated In Vitro Release Conditions --- p.37
Chapter 2.2.8.1. --- In the Absence of PLGA --- p.37
Chapter 2.2.8.2. --- In the Presence of PLGA --- p.37
Chapter 2.2.9. --- MicroBCÁёØ Protein Assay --- p.38
Chapter 2.2.10. --- Size Exclusion Chromatography (SEC) - High Performance Liquid Chromatography (HPLC) --- p.38
Chapter 2.2.11. --- ELISA --- p.39
Chapter 2.2.12. --- Bioactivity Assay --- p.40
Chapter 2.2.12.1. --- RhIFN --- p.40
Chapter 2.2.12.2. --- RhGM-CSF --- p.41
Chapter CHAPTER 3. --- Results and Discussions
Chapter 3.1. --- Sustained-release RhIFN Formulation --- p.45
Chapter 3.1.1. --- Partition Coefficient of RhIFN --- p.45
Chapter 3.1.2. --- Formulation Based on the Standard Aqueous-aqueous Emulsion (SA-AE) Method With Sodium Alginate as Stabilizer --- p.45
Chapter 3.1.2.1. --- Surface Morphology --- p.45
Chapter 3.1.2.2. --- Formulation Characterization --- p.46
Chapter 3.1.2.3. --- In Vitro Release of RhIFN from PLGA Microsheres --- p.54
Chapter 3.1.3. --- Formulation Based on the Freezing-induced Phase Separation (FIPS) Technique without Sodium Alginate --- p.56
Chapter 3.1.3.1. --- Formulation Characterization --- p.56
Chapter 3.1.3.2. --- In Vitro Release of RhIFN from PGLA Microsphees --- p.59
Chapter 3.2. --- RhIFN Stability Assessment under Simulated In Vitro Release Conditions --- p.63
Chapter 3.2.1. --- In the Absence of PLGA --- p.63
Chapter 3.2.2. --- In the Presence of PLGA --- p.65
Chapter 3.3. --- Sustained-release RhGM-CSF Formulation --- p.68
Chapter 3.3.1. --- Partition Coefficient Determination of RhGM-CSF Between PEG and Dextran --- p.68
Chapter 3.3.2. --- Formulation Based on Freezing-induced Phase Separation --- p.68
Chapter 3.3.2.1. --- Validation of MTT Assay Conditions --- p.69
Chapter 3.3.2.2. --- Formulation Characterization --- p.71
Chapter 3.3.2.3. --- In Vitro Release of RhGM-CSF from PLGA Microspheres --- p.75
Chapter CHAPTER 4. --- Conclusion and Future Studies
Chapter 4.1. --- Conclusion --- p.78
Chapter 4.2. --- Future Studies --- p.79
References --- p.80
Onadeko, Toluwalope. "Preparation and characterization of oil-in-water nano-emulsions of trifluoperazine for parenteral drug delivery." 2009. http://digital.library.duq.edu/u?/etd,97910.
Full textPatra, Debabrata. "Colloidal microcapsules: Surface engineering of nanoparticles for interfacial assembly." 2011. https://scholarworks.umass.edu/dissertations/AAI3465065.
Full textBertrand, Nicolas. "Caractérisation de la pharmacocinétique de formulations sensibles au pH et de formulations destinées au traitement des intoxications médicamenteuses." Thèse, 2011. http://hdl.handle.net/1866/5425.
Full textDrug delivery is the field of pharmaceutical sciences which focuses on altering the immediate environment of drug molecules to improve their efficacy and safety. Drug delivery systems can potentiate the effect of active principles or alleviate their side effects by modifying their circulation profiles and/or biodistribution. The objective of this research project was to investigate the role of pharmacokinetic (PK) analysis in the development of novel drug delivery systems. PK analysis is generally applied to describe and predict the blood concentration profiles of low molecular weight drugs and their metabolites. Nevertheless, it is herein used to characterize the circulation of 2 liposomal formulations: pH-sensitive liposomes designed to alter the intracellular distribution of drugs and liposomes with transmembrane pH gradient for drug detoxification. The first series of experiments were designed to study the circulation kinetics of a pH-sensitive polymer prepared with N-isopropylacrylamide (NIPAM) and methacrylic acid (MAA). The copolymer p(NIPAM-co-MAA) is used in our laboratory to prepare serum-stable, PEGylated, pH-sensitive liposomes. The circulation profiles of polymers with different characteristics were characterized. The parameters which impacted the fate of the macromolecules were the length of the polymer chain, its cloud point and the presence of a hydrophobic anchor at one extremity of the molecule. The glomerular filtration cut-off of the polymer was determined to be around 32,000 g/mol. PK analysis allowed to conclude that the complexes prepared by anchoring the polymer on the surface of the liposomes remained stable in the bloodstream. This data established that pH-sensitive vesicular formulations could be produced using a polymer which could be excreted through renal filtration. It also confirmed that the formulation remained intact in the bloodstream. The second part of this work involved the development of liposomes with a transmembrane pH gradient designed to treat cardiovascular drug intoxications. Liposomes were designed and optimized in vitro to capture a model cardiovascular drug, diltiazem (DTZ). In vitro, the liposome uptake capacity was 40-fold higher than the lipid emulsion used in the clinic. PK analysis was used to verify the stability of the formulation in vivo, and to assess the impact of the liposomes on the plasma concentration of DTZ and its principal active metabolite, deacetyl-diltiazem (DAD). It was shown that the vesicles were able to capture and sequester DTZ and DAD. Injection of liposomes 2 min prior to administration of DTZ significantly increased the area under the plasma-concentration vs. time curve of both DTZ and DAD, while lowering their clearance and volume of distribution. The impact of the changes in PK on the pharmacological effect of the drug was also investigated. Liposomes tempered the hypotensive effect of the drug when the latter was administered via an intravenous bolus or a 1-h perfusion. Throughout this work, PK analysis proved to be an efficient tool to study the ability of transmembrane pH gradient liposomes to alter the blood circulation profiles of a cardiovascular drug, and to reduce its pharmacological effect. This proof of concept establishes firm ground for the further development of this colloidal formulation to treat drug intoxications. This work pointed out the relevance of PK analysis for the development of multi-purpose, colloidal drug delivery systems. At this stage, the predictive nature of the analysis was not exploited, but its descriptive properties allowed objective comparison of the circulation profiles of distinct systems and pertinent conclusions concerning their fate in vivo.