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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Micropart?culas de poli (?cido l?tico-co-?cido glic?lico) obtidas por spray drying para a libera??o prolongada de metotrexato

Oliveira, Alice Rodrigues de 19 December 2011 (has links)
Made available in DSpace on 2014-12-17T14:16:27Z (GMT). No. of bitstreams: 1 AliceRO_DISSERT.pdf: 2104659 bytes, checksum: 208850f5293dd4764037ec4c490d3636 (MD5) Previous issue date: 2011-12-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Methotrexate (MTX) is a drug used in the chemotherapy of some kind of cancers, autoimmune diseases and non inflammatory resistant to corticosteroids uveits. However, the rapid plasmatic elimination limits its therapeutic success, which leads to administration of high doses to maintain the therapeutic levels in the target tissues, occurring potential side effects. The aim of this study was to obtain spray dried biodegradable poly-lactic acid co-glycolic acid (PLGA) microparticles containing MTX. Thus, suitable amounts of MTX and PLGA were dissolved in appropriate solvent system to obtain solutions at different ratios drug/polymer (10, 20, 30 and 50% m/m). The physicochemical characterizing included the quantitative analysis of the drug using a validate UV-VIS spectrophotometry method, scanning electron microscopy (SEM), infrared spectrophotometry (IR), thermal analyses and X-ray diffraction analysis. The in vitro release studies were carried out in a thermostatized phosphate buffer pH 7.4 (0.05 M KH2PO4) medium at 37?C ? 0.2 ?C. The in vitro release date was subjected to different kinetics release models. The MTX-loaded PLGA microparticles showed a spherical shape with smooth surface and high level of entrapped drug. The encapsulation efficiency was greater then 80%. IR spectroscopy showed that there was no chemical bond between the compounds, suggesting just the possible occurrence of hydrogen bound interactions. The thermal analyses and X-ray diffraction analysis shown that MTX is homogeneously dispersed inside polymeric matrix, with a prevalent amorphous state or in a stable molecular dispersion. The in vitro release studies confirmed the sustained release for distinct MTX-loaded PLGA microparticles. The involved drug release mechanism was non Fickian diffusion, which was confirmed by Kornmeyer-Peppas kinetic model. The experimental results demonstrated that the MTX-loaded PLGA microparticles were successfully obtained by spray drying and its potential as prolonged drug release system. / O metotrexato (MTX) ? um f?rmaco utilizado na quimioterapia de alguns tipos de c?ncer, doen?as autoimunes e uve?tes n?o inflamat?rias resistentes aos corticoster?ides. No entanto, sua r?pida elimina??o plasm?tica limita o sucesso terap?utico, levando ? necessidade de altas doses para manuten??o da concentra??o efetiva no tecido alvo, ocasionando o potencial surgimento de rea??es adversas. O objetivo principal desse estudo foi obter um sistema microparticulado biodegrad?vel ? base de ?cido poli (?cido l?tico-co-?cido glic?lico) (PLGA) por spray drying para libera??o prolongada do MTX. Para isso, quantidades distintas de MTX e PLGA foram dissolvidas em sistema solvente adequado para obter solu??es com diferentes propor??es de f?rmaco em rela??o ao pol?mero (10, 20, 30 e 50% m/m). A caracteriza??o f?sicoqu?mica incluiu an?lise quantitativa do f?rmaco incorporado na matriz polim?rica por espectrofotometria UV-VIS em 303nm previamente validada, microscopia eletr?nica de varredura (MEV), espectrofotometria de infravermelho (IV), an?lises t?rmicas e difra??o de raios-X (DRX). O perfil de libera??o in vitro do f?rmaco nas micropart?culas foi realizado em tamp?o fosfato (0.05 M KH2PO4) em banho termostatizado 37 ?C ? 0.2 ?C. Os dados obtidos do estudo de libera??o in vitro foram submetidos a diferentes modelos cin?ticos de libera??o. As micropart?culas de PLGA contendo o MTX apresentaram a forma esf?rica, uniforme, com superf?cie aparentemente lisa. O n?vel de efici?ncia de encapsula??o foi superior a 80%. A espectroscopia na regi?o do infravermelho demonstrou que n?o ocorreu liga??o qu?mica entre os componentes dos sistemas, no entanto foi observado forte intera??o entre o MTX e PLGA indicando prov?vel ocorr?ncia de pontes de hidrog?nio. An?lise XII t?rmica e DRX demonstraram que o MTX est? distribu?do na matriz polim?rica com a preval?ncia do estado amorfo ou em dispers?o molecular. O estudo de libera??o in vitro confirmou o perfil de libera??o prolongada para as diferentes micropart?culas. O mecanismo de libera??o envolvido foi por difus?o n?o Fickiana, ao qual foi determinado a partir do modelo cin?tico de Kornmeyer- Peppas. Os resultados experimentais demonstraram o sucesso na obten??o das micropart?culas de PLGA contendo o MTX por spray drying e seu potencial como sistema de libera??o prolongada do f?rmaco.
182

Estudo da composição química, de atividades biológicas e microencapsulação do óleo essencial dos frutos de Pterodon emarginatus Vogel - Fabaceae ("sucupira") / Study chemical composition, biologycal activity and microencapsulation of essencial oil of the fruits from Pterodon emarginatus Vogel - Fabaceae ("sucupira")

ALVES, Suzana Ferreira 28 February 2012 (has links)
Made available in DSpace on 2014-07-29T16:11:50Z (GMT). No. of bitstreams: 1 Dissertacao Suzana Ferreira Alves.pdf: 1091463 bytes, checksum: f169757b64e48eb6022ea0919135c602 (MD5) Previous issue date: 2012-02-28 / The present work aimed to do the study of chemical variability, evaluating biological activities and microencapsulate the essential oil of the fruits of Pterodon emarginatus Vogel (Fabaceae). Chapter 1 presents the study of the chemical variability of essential oil from fruits of sucupira of 11 individual of the Brazilian savanna, collected from five different populations, and were identified as its chemical composition by gas chromatography coupled to mass spectrometry (GC/MS), used for data analysis to multivariate statistical tool that indicated compounds β caryophyllene and α copaene as the main discriminant of the samples studied, both of which are of greater significance. Chapter 2 describes the antimicrobial activity and chemical composition of total oil of the fruits of sucupira, four samples being analyzed, three of the city of Jussara GO and one of region of Jaciara MT. The oils tested showed good antimicrobial activity against bacteria Gram positive (Gram (+)) and moderate activity against Enterobacter aerogenes ATCC 13048. Chapter 3 describes the process of obtaining microcapsules containg essential oil (OE) of sucupira employing the technique of spray drying and the development and validation methodology for quantification of the compound β caryophyllene. Were used gum Arabic and maltodextrin as wall material and prepared five different dispersions (Emulsion 1-E1, Emulsion 2-E2, Emulsion 3-E3, Emulsion 4-E4 and Emulsion 5-E5) which then were atomized in spray dryer. The results show that the drying condition most appropriate was sprinkler beak of 1,2 mm of diameter, power flow the emulsion in system of 4 mL/min, inlet temperature of 160ºC, air flow of 40 L/min e and pressure of 60 psi. Among the emulsions, E2 was standardized with adequate proportion of essential oil and wall materials, by presenting microcapsules (MOE) for having thick-walled, with a pronounced retention of essential oil, spherical morphology and low hygroscopicity. The method developed and validated proved to be linear, precise, acuurate and robust. Chapter 4 presents the evaluation of biological activities of antimicrobial essential oil of PES-01 employing the technique of broth microdilution and antinociceptive and anti-inflamatory activities performed to the microcapsules with the essential oil. The models of pain induced by formalin and hot plate were used to assess the antinociceptive activity and the model of carrageenan-induced pleurisy and Evans blue for evaluation of anti-inflamatory activity. The OE has weak antimicrobial activity (500 μg mL-1) against bacteria Gram (+) and against the fungi of the genus Cryptococcus was inactive against S. aureus ATCC 25923, against bacteria Gram (-) and against the fungi of the genus Candida. OE reduced by 61,54% (300 mg kg-¹) of the reactivity to pain. The MOE reduced 40,87% (1,0 g kg-¹) and 41,57% (2,0 g kg-¹) in first phase of the test formalin-induced pain, suggesting, anti-nociceptive activity. The 2nd phase of the test, the essential oil inhibited 52,35% of the pain related to inflammatory mediators and the microcapsules decreased from 25,86% - 55,60% of the pain. MOE at a dose of 1,0 g kg-¹ showed anti-nociceptive activity in hot plate model, suggestion central analgesic activity. In the arrageenaninduced pleurisy the MOE reduced 25,44% of the complete migration of leukocytes and significantly decreased the concentration of Evans blue in 24,18%, which demonstrates important anti-inflamatory activity. / O presente trabalho teve como objetivos realizar o estudo da variabilidade química, avaliar atividades biológicas e microencapsular o óleo essencial dos frutos de Pterodon emarginatus Vogel (Fabaceae). O capítulo 1 traz o estudo da variabilidade química do óleo essencial dos frutos de sucupira extraído de 11 indivíduos do cerrado brasileiro, coletados de 5 diferentes localidades, e que foram identificados quanto sua composição química através de cromatografia gasosa acoplada a espectrometria de massas (CG/EM), para análise dos dados empregou se a ferramenta estatística multivariada que indicou os compostos β cariofileno e α copaeno como os principais discriminantes das localidades estudadas, sendo ambos de maior significância. O capítulo 2 descreve a atividade antimicrobiana e a composição química do óleo total dos frutos de sucupira, sendo quatro amostras analisadas, três da cidade de Jussara-GO e uma da região de Jaciara-MT, os óleos testados apresentaram boa atividade antimicrobiana contra bactérias Gram-positivas (Gram (+)) e moderada atividade contra Enterobacter aerogenes ATCC 13048. O capítulo 3 descreve o processo de obtenção de microcápsulas contendo o óleo essencial (OE) de sucupira empregando a técnica de spray drying e o desenvolvimento e validação de metodologia para quantificação do composto β cariofileno. Foram utilizados goma arábica e maltodextrina como material de parede e preparadas 5 diferentes dispersões (Emulsão 1-E1, Emulsão 2-E2, Emulsão 3-E3, Emulsão 4-E4 e Emulsão 5-E5), que em seguida foram atomizadas em spray dryer. Os resultados mostram que a condição de secagem mais adequada foi bico aspersor de 1,2 mm de diâmetro, fluxo de alimentação da emulsão no sistema de 4 mL/min, temperatura de entrada de 160ºC, fluxo de ar de 40 L/min e pressão de 60 psi. Dentre as emulsões, E2 foi padronizada com a proporção adequada de óleo essencial e dos materiais de parede, por apresentar microcápsulas (MOE) de parede espessa, com pronunciada retenção do óleo essencial, morfologia esférica e baixa higroscopicidade. O método desenvolvido e validado mostrou ser linear, preciso, exato e robusto. O capítulo 4 traz a avaliação de atividades biológicas antimicrobiana do óleo essencial de PES-01 pela técnica de microdiluição em caldo e atividades antinociceptiva e anti inflamatória realizadas para as microcápsulas contendo o óleo essencial. Os modelos de dor induzida por formalina e placa quente foram empregados para avaliar a atividade antinociceptiva e o modelo de pleurisia induzida por carragenina e azul de Evans para avaliação da antividade antiinflamatória. O OE apresentou fraca atividade antimicrobiana (500 μg mL-¹) para bactérias Gram (+) e fungos do gênero Cryptococcus, foi inativo para S. aureus ATCC 25923, contra bactérias Gram (-) e contra fungos do gênero Candida. OE reduziu em 61,54% (300 mg kg-¹) a reatividade à dor. As MOE reduziram 40,87% (1,0 g kg-¹) e 41,57% (2,0 g kg-¹) na 1ª fase do teste de dor induzida por formalina, sugerindo atividade antinociceptiva, na 2ª fase do teste, o óleo essencial inibiu 52,35% da dor relacionada aos mediadores da inflamação e as microcápsulas reduziram de 25,86% a 55,60% da dor. MOE na dose de 1,0 g kg-¹ demonstraram atividade antinociceptiva no modelo de placa quente, sugerindo atividade analgésica central. Na pleurisia induzida por carragenina as MOE reduziram 25,44% da migração total de leucócitos e diminuíram significativamente a concentração de azul Evans em 24,18%, o que demonstra importante atividade anti inflamatória.
183

EFFECTS OF FORMULATION COMPONENTS AND DRYING TECHNIQUES ON STRUCTURE AND PHYSICAL STABILITY OF PROTEIN FORMULATIONS

Tarun Tejasvi Mutukuri (11581819) 22 April 2022 (has links)
<p>  </p> <p>With the recent growth in demand for biologics across the globe, it remains critical to manufacture these biologics in solid-state to improve stability as well as to increase the ease of transportation across the world. To meet these increased demands, it is of paramount importance to use various processing methods that have shorter processing times. It is also important to understand the impact of the processing methods and various formulation components on the stability of the proteins.  In Chapter 1, a review of the various processing methods that are used in the industry along with additional processing methods that are being investigated will be discussed. The common drying methods such as lyophilization and spray drying along with the novel techniques as well as specific examples of processing parameters to improve the processing conditions that better suit the protein formulations will be mentioned. </p> <p>The studies in Chapter 2 examined the effects of processing methods (freeze drying and spray freeze drying) and the excipients on the protein structure and physical stability. Protein solids containing one of two model proteins (lysozyme or myoglobin) were produced with or without excipients (sucrose or mannitol) using freeze drying or spray freeze drying (SFD). The protein powders were then characterized using solid-state Fourier transform infrared spectroscopy (ssFTIR), differential scanning calorimetry (DSC), circular dichroism spectrometry (CD), size exclusion chromatography (SEC), BET surface area measurements, and solid-state hydrogen-deuterium exchange with mass spectrometry (ssHDX-MS). ssFTIR and CD could identify little to no difference in the structure of the proteins in the formulation. ssHDX-MS was able to identify the population heterogeneity, which was undetectable by conventional characterization techniques of ssFTIR and CD. ssHDX-MS metrics such as Dmax and peak area showed a good correlation with the protein physical instability (loss of the monomeric peak area by size exclusion chromatography) in 90-day stability studies conducted at 40oC for lysozyme.  The higher specific surface area was associated with greater loss in monomer content for myoglobin-mannitol formulations as compared to myoglobin-only formulations. Spray freeze drying seems a viable manufacturing technique for protein solids with appropriate optimization of formulations. The differences observed within the formulations and between the processes using ssHDX-MS, BET surface area measurements, and SEC in this study provide an insight into the influence of drying methods and excipients on protein physical stability.</p> <p>Based on this work, it was identified that spray freeze drying can be a viable alternative to produce solid-state protein formulations with similar stability as the freeze drying process. However, due to the long processing times and scale-up issues involved in the spray freeze drying process, there is a necessity to explore additional drying processes. Chapter 3 focuses on using another novel technique known as electrostatic spray drying (ESD) to produce solid-state protein formulations at lower drying temperatures than conventional spray drying and its effect on protein stability. A mAb formulation was dried by either conventional spray drying or electrostatic spray drying with charge (ESD). The protein powders were then characterized using solid-state Fourier transform infrared spectroscopy (ssFTIR), differential scanning calorimetry (DSC), size exclusion chromatography (SEC), and solid-state hydrogen/deuterium exchange with mass spectrometry (ssHDX-MS). Particle characterizations such as BET surface area, particle size distribution, and particle morphology were also performed. Conventional spray drying of the mAb formulation at the inlet temperature of 70oC failed to generate dry powders due to poor drying efficiency; electrostatic spray drying at the same temperature at 5kV enabled the formation of powder formulation with satisfactory moisture contents. Deconvoluted peak areas of deuterated samples from the ssHDX-MS study showed a good correlation with the loss of the monomeric peak area measured by size exclusion chromatography in the 90-day accelerated stability study conducted at 40oC. Low-temperature (70oC inlet temperature) drying with an electrostatic charge (5kV) led to better protein physical stability as compared with the samples spray-dried at the high temperature (130oC inlet temperature) without charge.</p> <p>This study shows that electrostatic spray drying can produce solid monoclonal antibody formulation at a lower inlet temperature than traditional spray drying with better physical stability. While ESD can be a viable option for thermal-sensitive formulations, it is important to understand the impact of various formulation components on the stability of the proteins while using spray drying. Based on our previous studies, a good understanding of the effect of different sugars and the presence of surfactants on the spray-dried proteins has been established. However, the impact of the selection of buffer on protein stability has not been studied. In Chapter 4, the effect of buffer salts on the physical stability of spray dried and lyophilized formulations of a model protein, bovine serum albumin (BSA) were examined. BSA formulations with various buffers were dried by either lyophilization or spray drying. The protein powders were then characterized using solid-state Fourier transform infrared spectroscopy (ssFTIR), powder X-ray diffraction (PXRD), size exclusion chromatography (SEC), solid-state hydrogen/deuterium exchange with mass spectrometry (ssHDX-MS), and solid-state nuclear magnetic resonance spectroscopy (ssNMR). Particle characterizations such as BET surface area, particle size distribution, and particle morphology were also performed. Results from conventional techniques such as ssFTIR did not exhibit correlations with the physical stability of studied formulations. Deconvoluted peak areas of deuterated samples from the ssHDX-MS study showed a satisfactory correlation with the loss of the monomeric peak area measured by SEC (R2 of 0.8722 for spray-dried formulations and 0.8428 for lyophilized formulations) in the 90-day accelerated stability study conducted at 40oC. PXRD was unable to measure phase separation in the samples right after drying. In contrast, ssNMR successfully detected the occurrence of phase separation between the succinic buffer component and protein in the lyophilized formulation, which results in a distribution of microenvironmental acidity and the subsequent loss of long-term stability. In summary, this study demonstrated that buffer salts have less impact on physical stability for the spray-dried formulations than the lyophilized solids.</p> <p>The study in Chapter 5 looked at examining the physical stability of spray freeze dried (SFD) bovine serum albumin (BSA) solids produced using the radio frequency (RF)-assisted drying technique. BSA formulations were prepared with varying concentrations of trehalose and mannitol, with an excipient-free formulation as control. These formulations were produced using traditional spray freeze drying (SFD) or RF-assisted spray freeze drying (RFSFD). The dried formulations were then characterized using solid-state Fourier transform infrared spectroscopy (ssFTIR), Karl Fischer moisture content measurement, powder X-ray diffraction (PXRD), size exclusion chromatography (SEC), solid-state hydrogen/deuterium exchange with mass spectrometry (ssHDX-MS). Traditional characterization tools such as ssFTIR and moisture content did not have a good correlation with the physical stability of the formulations measured by SEC. ssHDX-MS metrics such as the maximum deuterium uptake (Dmax) (R2 = 0.791) and deconvoluted peak areas of the deuterated samples (R2 = 0.914) showed a satisfactory correlation with the SEC stability data. RFSFD improved the stability of formulations with 20 mg/ml of trehalose and no mannitol and had similar stability with all other formulations as compared to SFD. This study demonstrated that the RFSFD technique can significantly reduce the duration of primary drying cycle from 48 h to 27.5 h while maintaining or improving protein physical stability as compared to traditional lyophilization.</p> <p>Lastly, Chapter 6 consists of a summary of the conclusions formed from the work presented in this thesis. Furthermore, suggestions for future work are provided based on observations of results, less-explored areas of formulation and processing conditions as well as characterization tools to understand effects on protein physical stability.</p> <p><br></p>
184

Microsphères nano-structurées obtenues par atomisation-séchage : synthèses, caractérisation, encapsulation et libération de principes actifs / Spray-dried nanostructured microspheres : synthesis, characterization, encapsulation and release of durgs

Fatnassi, Mohamed 24 November 2010 (has links)
L'objectif de cette thèse consiste à développer une approche globale couplant les procédés sol-gel, les propriétés d'auto-assemblage des tensioactifs et l'atomisation séchage afin d'encapsuler directement des principes actifs dans des microsphères nanostructurées. Nous nous attachons en particulier à étudier les variations de la localisation et l'état physique des principes actifs en fonction des paramètres de synthèse. Le but de ce travail est également de mettre en relation les propriétés de libération avec la texture et la composition des microsphères. En parallèle, cette thèse a aussi pour objectifs la découverte de nouvelles familles de matériaux texturés et l'approfondissement des connaissances sur les mécanismes de formation des microsphères mésoporeuses. / For the first time, a new one-pot synthesis approach associating sol-gel, self-assembly andspray-drying allows in forming microspheres with tuneable textures (worm-like mesophases,drug nano-domains, core-shell organisation) and drug delivery properties (from burst todelayed releases). The parameters which control these properties are the surfactant content,the nature of the couples (drug, surfactant) as well as the functionalisation of the siloxanenetwork.
185

Pharmaceutical Nanocomposites : Structure–Mobility–Functionality Relationships in the Amorphous State

Hellrup, Joel January 2016 (has links)
Amorphous materials are found in pharmaceutical formulations both as excipients and active ingredients. Indeed, these formulations are becoming an essential strategy for incorporating drugs into well-performing solid dosage forms. However, there is an unmet need of better understanding of the microstructure and component interactions in amorphous formulations to be able to design materials with improved functionalities. The aim of this thesis is to give deepened knowledge about structure-mobility-functionality relationships in amorphous for-mulations by studying composites produced from sugars and filler particles. The structure, the mobility, and physical stability of the composite materials were studied using calorimetry, X-ray diffraction, microscopy, spectroscopy, and molecular dynamics simulations. Further, the moisture sorption of the composites was determined with dynamic vapor sorption. The compression mechanics of the composites was evaluated with compression analysis. It was demonstrated that fillers change the overall properties of the amorphous material. Specifically, the physical stability of the composite was by far improved compared to the amorphous sugar alone. This effect was pronounced for formulations with 60 wt% filler content or more. Amorphous lactose that normally recrystallizes within a few minutes upon humidity exposure, could withstand recrystallization for several months at 60% RH in composites with 80 wt% cellulose nanocrystals (CNC) or sodium montmorillonite (Na-MMT). The increased physical stability of the amorphous sugars was related to intra-particle confinement in extra-particle voids formed by the fillers and to immobilization of the amorphous phase at the surface of the fillers. Also, the composite formation led to increased particle hardness for the lactose/CNC and the lactose/Na-MMT nanocomposites. The largest effect on particle hardness was seen with 40-60 wt% nanofiller and could be related to skeleton formation of the nanofillers within the composite particles. The hygroscopicity for the lactose/Na-MMT nanocomposites decreased as much as 47% compared to ideal simple mixtures of the neat components. The nanofillers did not influence the water sorption capacity in the amorphous domains; however, lactose (intercalated into Na-MMT) interacted with the sodium ions in the interlayer space which led to the lowered hygroscopicity of this phase. The thesis advanced the knowledge of the microstructure of amorphous pharmaceutical com-posites and its relationship with pharmaceutical functionalities. It also presented new approaches for stabilizing the amorphous state by using fillers. The concept illustrated here might be used to understand similar phenomena of stabilization of amorphous formulations.
186

Aproveitamento dos subprodutos de vinificação da uva Bordô (Vitis labrusca) para obtenção de pigmentos com propriedades funcionais / Use of vinification byproducts of Bordo grape (Vitis labrusca) to obtain pigments with functional properties

Souza, Volnei Brito de 04 March 2013 (has links)
O objetivo deste trabalho foi produzir pigmentos em pó a partir dos subprodutos de vinificação da uva tinta, variedade Bordô (Vitis labrusca), através da secagem em spray dryer utilizando maltodextrina como agente carreador. Foram estudados os efeitos das condições de processo sobre algumas propriedades físico-químicas, além da estabilidade e da atividade biológica do material obtido. Extratos etanólicos das cascas e sementes da uva foram obtidos e concentrados até um terço do volume inicial. Este extrato foi então misturado com o agente carreador maltodextrina 10 DE nas concentrações de 10, 20 ou 30% e atomizado em spray dryer, com vazão de alimentação de 44 mL/min e temperaturas do ar de entrada de 130, 150 ou 170°C, num total de nove ensaios. Além disso, foi obtida uma amostra de extrato concentrado liofilizado, sem a presença do agente carreador, para efeito de comparação. Avaliou-se o rendimento do processo de atomização; e para as amostras obtidas determinou-se o teor de umidade, retenção de antocianinas, higroscopicidade e solubilidade em água, a fim de verificar a influência das condições de processo sobre essas características. Estas amostras também foram avaliadas quanto à morfologia, distribuição do tamanho de partículas e isotermas de sorção de umidade. Todas as amostras obtidas (atomizadas e liofilizada) foram avaliadas quanto à cor instrumental, espectroscopia de infravermelho, estabilidade durante a estocagem, presença de compostos bioativos (fenólicos, flavonóides, antocianinas e proantocianidinas), além de atividade antioxidante, antimicrobiana e de inibição da arginase de Leishmania. As condições de processo avaliadas (temperatura de secagem e concentração de agente carreador) tiveram forte influência nas características estudadas. O teor de umidade, a retenção de antocianinas, a morfologia e o tamanho das partículas, foram bastante influenciados pela temperatura de secagem e pela concentração de agente carreador, enquanto que a higroscopicidade sofreu maior influência da concentração de agente carreador. Esse parâmetro também apresentou grande influência nas isotermas de sorção de umidade das amostras. Não houve grande interferência do processo de secagem na composição química do material obtido, evidenciada pelos espectros de infravermelho. Quanto à avaliação da estabilidade durante a estocagem, foi observado que as amostras contendo maltodextrina conservaram mais as antocianinas e a cor, quando comparadas com as amostras sem carreador e os extratos líquidos, indicando, que o processo de secagem e a presença do carreador, promoveram um efeito protetor aos compostos e sua cor. Todas as amostras apresentaram altos teores de flavonóides totais, antocianinas, proantocianidinas e elevados valores de atividade antioxidante variando de 314,06 a 441,04 &micro;molesTE/g de extrato seco pelo método DPPH e de 993,32 a 1138,68 &micro;molesTE/g de extrato seco pelo método FRAP. Apresentaram atividade antimicrobiana principalmente contra Staphylococcus aureus e Listeria monocytogenes. Além disso, tiveram grande capacidade de inibir a enzima arginase de Leishmania com porcentagem de inibição variando de 54,60 a 83,43%. Os resultados encontrados sugeriram que o processo de secagem em spray dryer com maltodextrina, dos extratos obtidos dos subprodutos da uva Bordô, produziu pós com diversas características interessantes, como baixa higroscopicidade, alta solubilidade e estabilidade, além de grande potencial biológico. Tais resultados evidenciam que este subproduto da indústria vinícola pode ser aproveitado como fonte natural de ingredientes funcionais. / The aim of this work was to produce powder pigments from grape byproducts of Bordo variety (Vitis labrusca) by spray drying using maltodextrin as carrier agent. The effects of process conditions on some physicochemical properties, stability and biological activity of the product were studied. Ethanol extracts were obtained from grape pomace (skins and seeds) and concentrated to one-third the initial volume. This extract was then mixed with the carrier agent 10 DE maltodextrin at concentrations of 10, 20 or 30% and atomized in a spray dryer, with feed flow rate of 44 mL/min and inlet drying air temperatures of 130, 150 or 170°C a total of nine tests. In addition, a sample of freeze-dried concentrated extract without carrier agent was obtained for comparison. It was evaluated process yield and the samples obtained were initially evaluated for moisture content, anthocyanins retention, hygroscopicity and solubility in water, in order to verify the influence of process conditions on these characteristics. These samples were also evaluated for morphology, particle size distribution and moisture sorption isotherms. All samples (spray-dried powders and freeze-dried extract) were evaluated for instrumental color, infrared spectroscopy, stability during storage, presence of bioactive compounds (phenols, flavonoids, anthocyanins and proanthocyanidins) plus antioxidant activity, antimicrobial activity and inhibition of Leishmania arginase. Process conditions evaluated (inlet drying air temperature and carrier agent concentration) had a strong influence on the characteristics studied. The moisture content, anthocyanin retention, morphology and particle size of the samples were strongly influenced by drying temperature and carrier agent concentration while the hygroscopicity suffered greater influence of the carrier agent concentration. The concentration of carrier agent also had great influence on the moisture sorption isotherms of the samples. There was no significant interference of the drying process on the chemical composition of the material evidenced by infrared spectroscopy. Regarding the evaluation of stability during storage, it was observed that the samples containing maltodextrin, retained much more anthocyanins and original color when compared with the sample without a carrier or liquid extracts, indicating both, the drying process and the presence of carrier, promoted a protective effect to the compounds and its color. All samples showed high levels of flavonoids, anthocyanins, proanthocyanidins and high levels of antioxidant activity ranging from 314.06 to 441.04 &micro;molTE/g of extract (dry weight), by DPPH and 993.32 to 1138.68 &micro;molTE/g of extract (dry weight) by FRAP method. Most samples showed antimicrobial activity against Staphylococcus aureus and Listeria monocytogenes. Moreover, had great ability to inhibit the enzyme arginase of Leishmania with inhibition percentage ranging from 54.60 to 83.43%. The results suggest that the drying process of Bordo grape pomace extracts in a spray dryer with maltodextrin, produced powders with various interesting characteristics such as low hygroscopicity, high solubility and stability, and large biological potential. This shows that this byproduct of wine industry can be used as a natural source of functional ingredients.
187

Polpa de guavira (Campomanesia cambessedeana Berg) desidratada em spray dryer: efeitos das condições de processo e composição da alimentação nas propriedades físico químicas e atividade antioxidante / Guavira (Campomanesia cambessedeana Berg) pulp dehydrated in spray dryer: effects of process conditions and feed composition on the physicochemical properties and antioxidant activity

Chung, Monique Mi Song 04 February 2016 (has links)
O objetivo desse trabalho foi obter polpa de guavira desidratada por atomização, utilizando maltodextrina ou goma arábica como agentes carreadores. Inicialmente, avaliou-se a influência das condições de processo, temperatura do ar de secagem (130, 155 e 180) °C e vazão volumétrica da mistura (20 e 40) mL/min, o tipo e concentração de agente carreador (10 e 20) % nas características físicas, físico-químicas e atividade antioxidante do produto obtido. As propriedades analisadas foram umidade, atividade de água, higroscopicidade, solubilidade, cor, distribuição e tamanho médio de partículas, morfologia, compostos fenólicos totais e atividade antioxidante. A temperatura do ar de secagem e a vazão volumétrica de alimentação influenciaram significativamente todas as propriedades da guavira em pó. A umidade e atividade de água apresentaram os menores valores na temperatura intermediária, independentemente do tipo e concentração do carreador usado. A solubilidade das amostras adicionadas de maltodextrina foram superiores às amostras com goma arábica. O aumento da concentração de agente carreador, em geral, proporcionou um aumento no parâmetro L* e diminuição dos parâmetros a* e b*, tornando as amostras mais claras e reduzindo as tonalidades vermelha e amarela. A guavira em pó apresentou coloração próxima do amarelo e marrom, com grande variação nos parâmetros de cor C* e H* em função das diferentes condições de secagem. A distribuição do tamanho de partículas não teve um padrão definido e o tamanho médio das amostras com maltodextrina foram maiores do que as com goma arábica para a temperatura do ar a 130 °C. No entanto, para as outras temperaturas (155 e 180) °C não houve um comportamento específico do tamanho das partículas em função da vazão de alimentação, tipo e ou concentração de agente carreador. A análise de microscopia eletrônica de varredura permitiu observar que as partículas obtidas tanto com maltodextrina como goma arábica apresentaram formato esférico, superfície rugosa e com adesão de partículas menores nas de maior tamanho, sendo que a superfície das partículas com goma arábica também apresentaram concavidades. A atividade antioxidante foi superior quando utilizada a temperatura de secagem intermediária. A partir das condições selecionadas na primeira etapa (temperatura do ar de 155 °C, vazão volumétrica da mistura de 40 mL/min e 10% de maltodextrina ou goma arábica) a polpa de guavira em pó foi caracterizada quanto a temperatura de transição vítrea, as isotermas de adsorção e a estabilidade à estocagem do ácido ascórbico, compostos fenólicos totais e da atividade antioxidante da polpa de guavira em pó produzida por spray drying ao longo de 120 dias. As temperaturas de transição vítrea foram de (25,2 ± 2,7 °C e 31,4 ± 0,4) °C para os pós produzidos com goma arábica e maltodextrina, respectivamente. O modelo de BET apresentou ajuste muito bom (R2&gt;0,99) para descrever o comportamento de sorção de água das amostras nas temperaturas de (20, 30 e 40) °C. A polpa de guavira em pó produzida com goma arábica apresentou maior adsorção de água do que as amostras obtidas com maltodextrina. No estudo da estabilidade, as amostras foram acondicionadas em embalagem de polietileno laminado e armazenadas a 25 °C e umidade relativa de 75%. A embalagem de polietileno laminado foi eficiente na manutenção do teor de ácido ascórbico e atividade antioxidante da guavira em pó por um período de 120 dias, independente do carreador adicionado. O teor de compostos fenólicos para a guavira em pó com goma arábica apresentou uma redução nos primeiros 22 dias, contudo a amostra com maltodextrina manteve-se estável durante 120 dias de armazenamento. / The aim of this work was to obtain dried guavira pulp by spray drying, using maltodextrin or arabic gum as carrier agents. Initially, it was evaluated the influence of the process conditions, inlet air temperature (130, 155 e 180) °C and mixture feed flow rate (20 e 40) mL/min, carrier agent type and concentration (10 e 20) % in physical, physicochemical properties and antioxidant activity of the product. The analyzed properties were moisture content, water activity, higroscopicity, solubility, distribution and average particle size, morphology, total phenolic compounds and antioxidant activity. The inlet air temperature and mixture feed flow significantly influenced all the properties of guavira powder. The moisture content and water activity showed lower values in intermediate temperature, independent of the carrier agent type and concentration. The solubility of the samples with maltodextrin were higher than the samples with arabic gum. Increasing the carrier agent concentration generally resulted in an increase of the parameter L* and a reduction of a* and b* parameters, making lighter samples and reducing the red and yellow hues. The color of the guavira powder presented next to yellow and brown coloring, with great variation in parameters C* and H* depending on the different drying conditions. The size distribution of the particles had no definite pattern and the particles average size of the samples with maltodextrin were higher the samples with arabic gum for the inlet air temperature at 130 °C. However, for the other temperatures (155 and 180) °C there is a specific behavior of the particle size depending of the feed flow rate, carrier agent type and concentration. The scanning electronic microscopic analysis observed that the particles obtained with maltodextrin or arabic gum presented spherical, roughness surface and adhesion of the smaller particles into larger, the particles with arabic gum also presented concavities. The antioxidant activity was higher at intermediate inlet air temperature. From the selected conditions at the first phase (inlet air temperature of 155 °C, feed flow rate of 40 mL/min and 10% of maltodextrina or arabic gum) the guavira pulp powder were evaluated the glass transition temperature, the adsorption isotherms and the storage stability of ascorbic acid and antioxidant activity of the guavira powder produced to over 120 days. The glass transition temperatures were (25,2 ± 2,7 °C e 31,4 ± 0,4) °C for the powder obtained with arabic gum and maltodextrin, respectively. The BET model presented good adjustment (R²&gt;0,99) to describe the water sorption behavior of the samples at test temperatures of (20, 30 e 40) °C. The guavira powder with arabic gum showed higher water adsorption than the samples with maltodextrin. In the stability study, samples were packed in polyethylene-laminated packaging and stored at 25 °C and relative humidity of 75%. The packaging was effective in maintaining ascorbic acid and antioxidant activity of the guavira powder for a period of 120 days for samples with the addition of maltodextrin and gum arabic. The content of phenolic compounds for guavira powder with gum arabic showed a reduction in the first 22 days, but the sample with maltodextrin remained stable for 120 days of storage.
188

OTIMIZAÇÃO DO MÉTODO DE EXTRAÇÃO DE CELULOSE NANOCRISTALINA PARA VALORIZAÇÃO DE RESÍDUOS LIGNOCELULÓSICOS

Ditzel, Fernanda Izabelle 08 July 2016 (has links)
Made available in DSpace on 2017-07-21T20:43:49Z (GMT). No. of bitstreams: 1 Fernanda Izabelle Ditzel.pdf: 4089923 bytes, checksum: 47704f1f43b93ae17b2605e30dc4d650 (MD5) Previous issue date: 2016-07-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nanocrystalline cellulose is an aqueous suspension containing whiskers which have high crystallinity and high specific surface area. This material can be obtained from lignocellulosic fibers by means of an acid hydrolysis process. The characteristics of the nanocrystalline cellulose depends of the hydrolysis conditions, which may vary according to the following parameters: concentration of acid, fiber to acid ratio, temperature and reaction time. Therefore, the influence of these parameters was evaluated in a study conducted for the microcrystalline cellulose. From this, optimized conditions were determinated for obtaining nanocrystalline cellulose suspensions with maximum yield or high crystallinity index or high zeta potential. The nanocrystalline cellulose suspension which showed maximum yield was selected for the surface modification with a cationic surfactant and posteriorly submitted to the spray-drying process. The produced, microparticles are suitable for use in the composite processing by extrusion. Based on the optimized hydrolysis conditions, residues of pine wood and corncob were submitted to the process of nanocrystalline cellulose extraction. For this, it was necessary to carry out a procedure for the isolation of cellulose, which consisted of acetosolv pulping and bleaching. The results showed that was possible to extract nanocrystalline cellulose with suitable characteristics for use in industrial applications. Compared with the commercial microcrystalline cellulose, the residues provided a yield approximately 76.0% lower in the nanocellulose extraction. Therefore, further studies are necessary to improve this characteristic. Finally, the black liquor from acetosolv pulping was used for the lignin recovery. It is suggested that lignin can be used economically for the production of aromatic compounds. / A celulose nanocristalina é uma suspensão aquosa contendo whiskers, os quais possuem elevadas cristalinidade e área superficial específica. Esta pode ser obtida a partir de fibras lignocelulósicas por meio de um processo de hidrólise ácida. As características da celulose nanocristalina dependem das condições de hidrólise, as quais podem variar de acordo com os seguintes parâmetros: concentração de ácido, razão fibra/ácido, temperatura e tempo de reação. Desta forma, a influência destes parâmetros foi avaliada em um estudo realizado para a celulose microcristalina. A partir disto, foram determinadas condições otimizadas para a obtenção de suspensões de celulose nanocristalina com máximo rendimento ou com elevado índice de cristalinidade ou com superior valor de potencial zeta. A suspensão de celulose nanocristalina que apresentou máximo rendimento foi selecionada para a modificação superficial com um surfactante catiônico e posterior secagem por atomização. Com isso, foram produzidas micropartículas para aplicação no processamento por extrusão de compósitos. Com base nas condições otimizadas de hidrólise, resíduos de madeira de pinus e de sabugo de milho foram submetidos ao processo de extração de celulose nanocristalina. Para isto, foi necessária a realização de um procedimento para o isolamento de celulose, o qual consistiu dos pré-tratamentos de polpação acetosolv e de branqueamento. A análise dos resultados mostrou que, a partir dos resíduos considerados, foi possível extrair celulose nanocristalina com características adequadas para uso em aplicações industriais. Contudo, em comparação com a celulose microcristalina comercial, os resíduos proporcionaram um rendimento aproximadamente 76,0 % inferior na extração de nanocelulose. Desta forma, estudos adicionais são necessários para a melhoria desta característica. Por fim, o licor negro proveniente da polpação acetosolv foi utilizado para a recuperação de lignina. Sugere-se que a lignina possa ser utilizada economicamente para a produção de compostos aromáticos.
189

Desenvolvimento e caracterização tecnológica de micropartículas de arrabidaea chica (h & B) B. Verl. obtidas por spray dryer / Development and characterization of arrabidaea chica (h & B) B. Verl. microparticles obtained by spray dryer

SAMPAIO, Rita de Cássia Almeida 08 1900 (has links)
Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2017-01-31T12:17:28Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_DesenvolvimentoCaracterizacaoTecnologica.pdf: 2723623 bytes, checksum: 3e840dbe1764d87fc2b9f7df3fa203eb (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2017-02-01T12:20:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_DesenvolvimentoCaracterizacaoTecnologica.pdf: 2723623 bytes, checksum: 3e840dbe1764d87fc2b9f7df3fa203eb (MD5) / Made available in DSpace on 2017-02-01T12:20:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_DesenvolvimentoCaracterizacaoTecnologica.pdf: 2723623 bytes, checksum: 3e840dbe1764d87fc2b9f7df3fa203eb (MD5) Previous issue date: 2012-08 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / O presente trabalho teve como objetivo o desenvolvimento tecnológico de formas farmacêuticas particuladas obtidas a partir de solução extrativa (tintura) de partes aéreas de Arrabidea chica (pariri), empregando-se a secagem por spray drying. Investigou-se a influencia de adjuvantes tecnológicos (maltodextrina e goma arábica, isoladas e em associação) no desempenho da secagem e nas propriedades dos produtos secos. A tintura de A. chica foi concentrada em evaporador rotativo obtendo-se o extrato concentrado (EC) o qual foi adicionado dos adjuvantes tecnológicos e submetidos a secagem em spray drying. O processo de secagem foi avaliado através da determinação da recuperação de produto e eficiência térmica. As micropartículas (ES) foram avaliadas quanto a umidade residual; atividade de água; diâmetro médio das partículas; densidade bruta, densidade de compactação e índices de fluidez, perfil térmico e espectroscópico por IV. O monitoramento químico foi realizado por espectrofotometria UV-vis, utilizando como marcador químico os flavonoides (Ft), polifenois (Pt) e taninos totais (Tt) presentes na A. chica. A atividade antioxidante do produto foi avaliada pelo método DPPH e quimioluminescência. O teor de umidade nas ES teve seus valores na faixa de 2,77 a 4,69% estando dentro do especificado. Os valores de atividade de água ficaram abaixo de 0.2, que e favorável a estabilidade físico-química e microbiológica. O percentual de degradação dos marcadores químicos nas ES em relação ao EC ficou na faixa de 24 a 46% para Ft, de 48 a 56% para Pt, e de 53 a 72% para Tt, que pode estar associada a degradação térmica e oxidação dos compostos. Na analise por CCD, a tintura, o EC e os ES apresentaram os padrões luteolina e canferol mostrando que o processo de secagem não causou a perda destes compostos. A distribuição granulométrica mostra que os ES apresentaram diâmetro médio em torno de 10 μm sendo que as partículas apresentaram morfologia esférica e algumas com superfície rugosa. Através da determinação dos índices de fluidez e de acomodação dos pós obteve-se resultados característicos de pós com baixa fluidez e características de compressibilidade. A atividade antioxidante dos ES apresentou valores entre 32,17 a 44,53 μg/mL. Na analise colorimétrica, os parâmetros comprovaram a coloração vermelha-amarelada. A recuperação de produto ficou na faixa de 60 a 65% e os valores de eficiência térmica ficaram entre 36 % e 39%. As analises de espectroscopia na região do infravermelho e analises térmicas se mostraram ferramentas importantes na caracterização físico-química e controle de qualidade dos sistemas micropartículados obtidos. / This work aimed the technological development of particulate dosage forms obtained from extraction solution (tincture) from aerial parts of Arrabidea chica (Pariri), using the spray drying. We investigated the influence of processing aids (maltodextrin and arabic gum, alone and in a mixer) in drying performance and product properties. A. chica tincture was concentrated on a rotary evaporator to obtain the concentrated extract (CE) which was added to the processing aids and subjected to spray drying. The drying process was assessed through determination of product recovery and thermal efficiency. Microparticles (ES) were evaluated for residual moisture, water activity, average particle diameter, bulk density, packing density and flow properties, thermal profile and IR spectroscopy. The chemical monitoring was performed by UV-vis spectrophotometer, using chemical marker flavonoids (Ft), polyphenols (Pt) and total tannins (Tt) in the A. chica. The antioxidant activity of the product was evaluated by DPPH and chemiluminescence. The moisture content of the ES had their values in the range 2.77 to 4.69% being within the specified. The water activity values were below 0.2, which supports the physical and chemical stability and microbiological of dried products. The percentage of degradation of chemical markers in ES regard to CE was in the range 24-46% for Ft, 48-56% for Pt and 53-72% to Tt, which may be associated with thermal degradation and oxidation of the same compounds. In TLC analysis, tincture, CE and ES showing the luteolin and kaempferol patterns indicate that the drying process does not cause the loss of these compounds. The particle size distribution shows that the ES showed an average diameter of about 10 μm and the particles had a spherical morphology and with some rough surface. The flowability indices and accommodation of the powders obtained results are typical of powders with low flowability and compressibility characteristics. The antioxidant activity of ES presented values between 32.17 to 44.53 mg / mL. In the colorimetric analysis, the parameters proved the yellowish-red color. The recovery of product was in the range 60-65% and the thermal efficiency values were between 36% and 39%. Analyses of infrared spectroscopy and thermal analysis proved important tools in the physico-chemical characterization and quality control systems microparticulate obtained.
190

Aerosolized Surfactants: Formulation Development and Evaluation of Aerosol Drug Delivery to the Lungs of Infants

Boc, Susan 01 January 2018 (has links)
The overall aim of this research project was to develop surfactant dry powder formulations and devices for efficient delivery of aerosol formulations to infants using the excipient enhanced growth (EEG) approach. Use of novel formulations and inline delivery devices would allow for more efficient treatment of infants suffering from neonatal respiratory distress syndrome and bronchiolitis. A dry powder aerosol formulation has been developed using the commercial product, Survanta ® (beractant) and EEG technology to produce micrometer-sized hygroscopic particles. Spray drying and formulation parameters were initially determined with dipalmitoylphosphatidylcholine (DPPC, the dominant phospholipid in pulmonary surfactant), which produced primary particles 1 um in size with a mass median aerodynamic diameter of 1-2 um. Investigation of dry powder dispersion enhancers and alcohol concentration on the effect of powder aerosol characteristics were performed with the Survanta-EEG formulation. The optimal formulation consisted of Survanta ® , mannitol and sodium chloride as hygroscopic excipients, and leucine as the dry powder dispersion enhancer, prepared in 20% v/v ethanol/water. The powders produced primary particles of 1 um with >50% of the particles less than 1 um. The presence of surfactant proteins and surface activity were demonstrated with the Survanta-EEG formulation following processing. A novel containment unit dry powder inhaler (DPI) was designed for delivery of the surfactant-EEG formulation using a low volume of dispersion air. Studies explored optimization of air entrainment pathway, inlet hole pattern, delivery tube internal diameter and length. With 3- 10 mg fill masses of spray dried surfactant powder, the DPI enabled delivery of >2 mg using one 3-mL actuation of dispersion air. Overall, it was possible to deliver >85% of the loaded fill mass using three actuations. Nebulized aerosol formulations are characterized with low delivered doses. Using a novel mixer-heater delivery system, the highest estimated percent lung dose achieved during realistic in vitro testing of a Survanta-EEG formulation aerosolized with a commercial mesh nebulizer was when nebulization was synchronized with inhalation of the breathing profile. Design changes to the mixer-heater system eliminated the need for synchronization, achieving an estimated percent lung dose of 31% of the nominal, an improvement compared with existing systems that achieve approximately <2% lung dose.

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