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Isotope analysis of incremental human dentine: towards higher temporal resolutionBeaumont, Julia, Gledhill, Andrew R., Montgomery, Janet January 2014 (has links)
Yes / Here we present a novel method which allows the measurement of the stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) from much smaller samples of dentine than previously possible without affecting the quality parameters. The reconstruction of the diet of past populations using isotopic analysis of bone collagen is a well-established tool. However, because of remodelling of bone throughout life, this gives a blurred picture of the diet. The analysis of δ13C and δ15N from tiny increments of dentine utilizes tissue that does not remodel and permits comparison, at the same age, of those who survived infancy with those who did not at high temporal resolution. This new method has been tested on archaeological teeth from two sites: three molar teeth from the 19th Century Kilkenny Union Workhouse Famine cemetery, Ireland; and three from the Anglian (5-7th centuries AD) cemetery at West Heslerton, Yorkshire, England, selected on the basis of their varied preservation. The methods of incremental dentine sectioning described in Beaumont et al (2013)[1] were carried out and a sub-section removed prior to denaturing and lyophilisation. The two sample sets, dentine and collagen from each section, were measured by isotope ratio mass spectrometry. The profiles produced from each of the six teeth studied show close correlation in isotope ratios indicating that demineralized dentine which has not been denatured and lyophilised produces isotope ratios comparable with dentine collagen. This finding allows analysis of extremely small samples of dentine which could previously not be measured using current instruments and methods.
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Baculovirus stability in serum-free lyophilized and wet storage conditionsColandro, Michelle Elizabeth 10 September 2013 (has links)
The baculovirus expression vector system (BEVS) is an effective way to produce recombinant proteins for biopharmaceuticals. However baculovirus stocks are stored in subzero temperatures to maintain virus stability, and fetal bovine serum is commonly used in the storage solution. In an effort to lower transportation and storage costs, a storage formulation that can effectively store the baculovirus in above frozen temperatures without the use of FBS would be beneficial. In this study, DMSO, ethylene glycol, glycerol, sucrose, sorbitol, sucrose-phosphate, and sucrose-phosphate-glutamate were added to baculovirus stock at various concentrations to determine the most effective stabilizer for virus storage at 4°C. Of the seven additives studied, 1 M sorbitol most effectively preserved baculovirus stock over a period of 47 weeks stored in 4°C. Formulations that include sucrose, L-arginine, and Pluronic F68 were created to determine their effectiveness on virus stability in a freeze-dried state stored at room temperature. In a lyophilized state, 0.5 M sucrose maintained baculovirus stock stability after 5 weeks of storage. Lyophilized stocks not containing sucrose were no longer infective after 5 weeks. / Master of Science
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IMPACT OF EXCIPIENTS ON MOBILITY AND STABILITY OF LYOPHILIZED BIOLOGICS FORMULATIONSCole Tower (18804880) 12 June 2024 (has links)
<p dir="ltr">Biologic drugs are a key defense against many health issues. In many cases, biologic drugs are not stable in the solution state and must be lyophilized. Lyophilization in the presence of excipients increases the stability of the drug by interactions with the excipients through hydrogen bonding, which will lower the local mobility of the drug. Key threats to stability include: inhomogeneity of the drug substance and excipients, high mobility, and crystallization. Solid-state nuclear magnetic resonance spectroscopy was used to identify crystallization, assess homogeneity, and measure the local mobility of lyophilized protein and mRNA/LNP systems. </p><p dir="ltr">The impact of disaccharide type and concentration on protein stability was explored. Human serum albumin (HSA) was lyophilized with disaccharides (sucrose and/or trehalose) in different relative concentrations, and solid-state nuclear magnetic resonance spectroscopy (ssNMR) <sup>1</sup>H T<sub>1</sub> and <sup>1</sup>H T<sub>1rho</sub> relaxation times were measured to determine the homogeneity of the lyophilized systems on 20-50 and 1-3 nm domains, and measure local mobility with <sup>1</sup>H T<sub>1</sub> relaxation times. HSA/sucrose systems had longer <sup>1</sup>H T<sub>1</sub> relaxation times and were slightly more stable than trehalose systems in almost all cases shown. HSA/sucrose/trehalose systems have <sup>1</sup>H T<sub>1</sub> relaxation times between the HSA/sucrose and HSA/trehalose systems and did not result in a more stable system compared to binary systems. Phase separation was evident in a sample containing relative concentrations of 10% HSA and 90% trehalose, suggesting trehalose crystallization during lyophilization. Under these stability conditions, a <sup>1</sup>H T<sub>1</sub> relaxation time below 1.5 s correlated with an unstable sample, regardless of disaccharide(s) used.</p><p dir="ltr">The effect of mannitol on protein stability was studied. Human serum albumin was lyophilized in binary systems with mannitol, and in ternary systems with sucrose or trehalose and mannitol. The monomer content of the HSA was monitored over 36 weeks of storage at 50 C. The amount of mannitol in the system dictated the ability of mannitol to crystallize, and the polymorph that mannitol crystallized into. In HSA/mannitol systems, mannitol crystallization caused inhomogeneity of the matrix, determined by <sup>1</sup>H T<sub>1rho</sub> relaxation times. Adding a disaccharide to the matrix, however, increased the homogeneity of the matrix. Addition of mannitol to a HSA/disaccharide matrix resulted in less stability at similar HSA:disaccharide ratios.</p><p dir="ltr">The impact of storage temperature on protein stability was investigated. Human serum albumin was lyophilized with sucrose or trehalose in histidine, phosphate, or citrate buffer. <sup>1</sup>H T<sub>1</sub> relaxation times were measured by ssNMR and were used to assess the homogeneity and mobility of the samples after zero, six, and twelve months at different temperatures. The mobility of the samples decreased after 6 and 12 months storage at elevated temperatures, consistent with structural relaxation of the amorphous disaccharide matrix. Formulations with sucrose had lower mobility and greater stability than formulations with trehalose.</p><p dir="ltr">The effect of an RF-assisted lyophilization method on homogeneity, mobility, stability, and moisture content was explored. This method, utilizing 18 GHz microwave frequency to accelerate the lyophilization cycle, resulted in equivalent or better stability for attenuated live virus or protein formulations, respectively. ssNMR showed comparable amounts of homogeneity in the formulations, however mobility of the samples produced by RF-assisted lyophilization was slightly higher.</p><p dir="ltr">A lyophilized mRNA/LNP formulation was prepared. Disaccharide type, disaccharide concentration, and freezing rate were found to alter critical quality attributes of the system. When mRNA/LNP formulations were stored at 4 C, solution formulations outperformed lyophilized formulations for at least 6 months. When mRNA/LNP formulations were stored at room temperature, solution formulations were superior for the first three months, however lyophilized formulations outperformed solution formulations after 6 months, with less growth in particle size and less loss of encapsulation efficiency. ssNMR was used to assess the interactions between the formulation components.</p>
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Resposta imune do antígeno de superfície de hepatite B administrado via nasal em nanopartículas de quitosana liofilizadas / Immune response to hepatitis B surface antigen administered nasally in freeze-dried chitosan nanoparticles.Saldaña Gonzales, Richard 18 February 2016 (has links)
A nanotecnologia tornou possível estruturar nanopartículas (NPs), utilizando-se polímeros biodegradáveis e atóxicos, como a quitosana (QS) - capaz de carrear e disponibilizar antígenos para a mucosa, devido sua propriedade mucoadesiva. Uma vacina liofilizada, em comparação a uma formulação líquida, possui inúmeras vantagens, tais como melhora na estabilidade do produto e melhor resistência às variações de temperatura, aumentando sua vida de prateleira e possibilitando melhor logística do produto aos locais onde o acesso à rede refrigerada é difícil; ademais, um produto liofilizado tem sua mucoadesividade aumentada, possibilitando maior tempo de permanência na mucosa. O presente trabalho teve como objetivo observar a resposta imune, em camundongos, de uma vacina desenvolvida por um mecanismo de entrega intranasal do HBsAg (Antígeno de superfície da Hepatite B) encapsulado pelo método de incorporação em nanopartículas de quitosana (NPs) liofilizadas. A formação das NPs foi realizada pela interação eletroestática da quitosana e do TPP (tripolifosfato de sódio), utilizando método de geleificação iônica. Formulações de NPs com glicina 5% apresentaram boas características após reconstituição, umidade residual inferior a 1% e processo de liofilização de 13 horas. Foi avaliada a imunogenicidade da inoculação do HBsAg em formulações de NPs de quitosana líquida e liofilizada, verificando-se que a forma líquida produziu anticorpos IgG contra HBsAg. / Nanotechnology has become possible to structure nanoparticles (NPs), using non-toxic and biodegradable polymers such as chitosan (CS), capable of carrying and deliver antigens to the mucosa, due to mucoadhesive property. A lyophilized vaccine compared to a liquid formulation, has several advantages, such as improved product stability as well as better resistance to temperature changes, increasing its shelf life allowing better logistics of the product to places where access to the chain cold is difficult and especially a lyophilized product increases muco-adhesiveness providing for longer staying in the mucosa. The work aims to observe the immune response in mice of vaccine developed by an intranasal delivery mechanism of HBsAg (hepatitis B surface antigen) encapsulated by incorporation method in chitosan nanoparticles (NPs) lyophilized. The formation of NPs was performed by electrostatic interaction between the chitosan and TPP (sodium tripolyphosphate) using the ionic gelation. Formulations showed good characteristics after reconstitution, residual humidity lower than 1% and the lyophilization process 15-hour. In this work, was evaluated the immunogenicity of inoculation of HBsAg in lyophilized and liquid formulations of chitosan nanoparticles, which liquid formulation produced anti-HBsAg antibodies.
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Produção, liofilização, purificação e determinação de especificidade da peptidase isolada do fungo Scopulariopsis koningii / Production, freeze drying, purification and determination of specific peptidase isolated from the fungus Scopulariopsis koningiiGiovanini, Gabriel Tescarolo 23 May 2014 (has links)
Peptidase pode ser considerada, como uma subclasse das enzimas hidrolíticas que ocupam uma posição central em relação às suas aplicações na área fisiológica e também na área comercial. As peptidases representam um dos três maiores grupos de enzimas industriais e são responsáveis por cerca de 60% da venda mundial de enzimas. O presente trabalho visa avaliar a produção de peptidase em fermentação submersa (FSm) pelo fungo Scopulariopsis koningii, utilizando como substrato farinha de pena (FP), a caracterização bioquímica parcial, secagem do extrato bruto, purificação da peptidase e determinação de especificidade da peptidase isolada. Para avaliar a influência da farinha de pena (FP), na produção de peptidases, foram adicionadas às porcentagens de 0,2; 0,4 e 0,8% no meio de cultura. Os melhores níveis de produção de peptidases pelo fungo Scopulariopsis koningii foram obtidos nas concentrações de 0,4% e 0,8% de FP em 48h de fermentação com 1.427 U/mL. A caracterização bioquímica parcial do extrato bruto foi realizada com azocaseína 1% preparada em tampão com pH adequado. A peptidase presente no extrato enzimático apresentou atividade ótima em pH 6,5 e temperatura ótima de 55°C. A peptidase foi inibida por PMSF, indicando a presença de resíduo de aminoácido serino no sítio catalítco, e desta forma sendo classificada como serino peptidase. Entretanto, também observamos uma inibição por EDTA, sugerindo a presença de uma metalo peptidase presente no extrato bruto, desta forma podemos sugerir que o fungo S. koningii na presença do meio contendo FP secreta duas subclasses; serino e metalo peptidase, ou secreta uma serino peptidase dependente de íon. Zimograma constatou a presença de duas enzimas. A atividade enzimática do extrato bruto diminuiu significativamente quando exposta os íons Al+3, Ni2+ e Cu2+ e aumentada quando adicionados os íons Ba2+, Ca2+ e Mg2+. A purificação da metalo peptidase presente no extrato enzimático envolveu sete etapas de purificação, sendo cromatografia de troca-iônica e gel filtração determinantes, com recuperação de 6% e purificação de 3,4 vezes. Utilizando a peptidase pura (metalo) realizouse a caracterização bioquímica funcional e a determinação dos parâmetros cinéticos, ambos utilizando o substrato peptídico de supressão intramolecular de fluorescência. A peptidase pura apresentou atividade ótima em pH 6,0 e temperatura ótima de 40°C e mostrou-se estável em ampla faixa de pH e temperatura. Foi modulada positivamente pelos íons Na+ e K+ e negativamente por Al3+ e Cu2+. A análise dos parâmetros cinéticos revelou uma grande influência de aminoácidos apolares do lado \"linha\" do substrato sintético na eficiência catalítica e no lado não \"linha\" grande influência de aminoácidos polares neutros e apolares. A secagem foi realizada por liofilização foram utilizados três tipos de adjuvantes: maltodextrina, manitol e glicina, em diferentes concentrações. Após a secagem foi realizado estudo da estabilidade nas temperaturas 4, 25 e 60°C por 32 dias para avaliar o desempenho dos adjuvantes na manutenção da atividade do extrato enzimático liofilizado. O adjuvante considerado mais eficaz foi a maltodextrina na concentração de 4,5% que manteve cerca de 93% da atividade do extrato enzimático liofilizado por 32 dias. / Peptidase can be considered as a subclass of hydrolytic enzymes which occupy a central position in relation to their applications in physiological area and also in the commercial area. Peptidases represent one of the three largest groups of industrial enzymes and account for about 60% of worldwide sales of enzymes. This study aims to evaluate the production of peptidase in submerged fermentation (FSm) by the fungus Scopulariopsis koningii, using as substrate feather meal (FP), the partial biochemical characterization, drying the crude extract, purification and determination of specific peptidase peptidase isolated. To evaluate the influence of feather meal (FM), in the production of peptidases, were added to the percentages of 0.2, 0.4 and 0.8% in the culture medium. The best levels of production of peptidases by the fungus Scopulariopsis koningii were obtained at concentrations of 0.4% and 0.8% of FP 48h fermentation with 1,427 U/mL. Partial biochemical characterization of the crude extract was performed with 1% azocasein prepared in buffer with appropriate pH. This in peptidase enzyme extract showed optimal activity at pH 6.5 and optimum temperature of 55°C. The peptidase was inhibited by PMSF, indicating the presence of a serine residue at amino acid catalytic site, and thus being classified as serine peptidase. However, we also observed an inhibition by EDTA, suggesting the presence of a metallo peptidase present in the crude extract, thus we suggest that the fungus S. koningii in the presence of medium containing secret FP two subclasses; serine peptidase and metal, or secretes a serine peptidase dependent ion. Zymogram found the presence of two enzymes. The enzymatic activity of the crude extract decreased significantly when exposed the Al 3+, Ni 2+ and Cu2+ ions and increased when added to Ba2+, Ca2+ and Mg2+ ions. The purification of metallo peptidase present in the enzyme extract involved seven stages of purification, and ion-exchange chromatography and gel filtration determinants, with recovery and purification of 6 % from 3.4 times. Using pure peptidase (metallo) held functional biochemical characterization and determination of kinetic parameters using both the intramolecular peptide substrate fluorescence suppression. Pure peptidase showed optimal activity at pH 6.0 and optimum temperature of 40°C and was stable in a wide range of pH and temperature. The positively modulated by Na+ and K+ and negatively by Al3+ and Cu2+. Analysis of kinetic parameters revealed a strong influence of nonpolar amino acid side \"line\" of the synthetic substrate in the catalytic efficiency and not on the side \"line\" great influence of nonpolar and polar neutral amino acids. The freeze drying was performed by three types of additives were used: maltodextrin, mannitol and glycine in different concentrations. After drying stability study was conducted at the temperatures 4, 25 and 60°C for 32 days to evaluate the performance of additives in maintaining the activity of the enzyme extract lyophilized. The adjuvant was found more efficacious maltodextrin in a concentration of 4.5%, which retained about 93% of the extract lyophilized enzyme activity for 32 days.
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Estratégias do processo para a conservação da potência da vacina rábica de uso veterinário por liofilização / Strategies of the process for the conservation of the potency of rabies vaccine for veterinary use by lyophilizationCaricati, Aline Tojeira Prestia 11 April 2012 (has links)
Uma vacina liofilizada, em comparação a uma líquida, possui inúmeras vantagens, tais como: a melhora na estabilidade do produto às variações de temperatura aumentando sua vida de prateleira, possibilitando uma melhor logística do produto aos locais onde o acesso à rede refrigerada é difícil. O presente trabalho visou investigar as estratégias do processo para a conservação da potência da vacina rábica de uso veterinário por liofilização. O material testado foi a vacina rábica inativada (VRI). Ao total foram testados 13 excipientes com três concentrações diferentes. O processo de triagem utilizado para a escolha das melhores formulações (VRI + excipiente) foi liofilização em microplacas próprias para cultivo celular adaptadas ao liofilizador, sendo posteriormente verificada a preservação da antigenicidade da vacina por meio do teste de ELISA. A análise estatística foi realizada no programa SPSS® v.17, aplicando análise de regressão para dados categóricos. A arginina 0,5%, o PEG 3350 0,5%, a sacarose 2%, a maltose 1% e a trealose 1% foram os que deram melhores resultados, um alto \"score\" de antigenicidade em comparação à vacina liofilizada sem adição de excipientes. A temperatura de colapso da VRI e de suas diversas formulações foi determinada por meio de um microscópio acoplado a um módulo de liofilização. A análise térmica foi realizada em Calorimetria Exploratória Diferencial (Differential Scanning Calorimetry - DSC). Realizou-se os seguintes testes para avaliação da VRI liofilizada em frasco ampola: microscopia eletrônica de varredura (MEV) para análise da estrutura da pastilha e o antibody-binding test (ABT) - Teste de ligação do anticorpo modificado para determinação da potência da VRI e suas formulações. A umidade residual da VRI com PEG3350 0,5% liofilizada foi determinada em temperatura constante de 100ºC resultou em 1,60%. A pastilha da vacina rábica + PEG 3350 0,5% liofilizada em frasco ampola apresentou a elegância farmacêutica esperada de um produto liofilizado. / A lyophilized vaccine, compared to a liquid form, has many advantages, such as the improvement in product stability to changes in temperature by increasing its shelf life, allowing better logistics for product to locations where access to chill is difficult to achieve. This work has investigated the strategies of the process for the conservation of the potency of rabies vaccine for veterinary use by lyophilization. The material tested is an inactivated rabies vaccine (VRI). Altogether 13 excipients were tested with three different concentrations. The screening process used to choose best formulation (s) (VRI + excipient) was lyophilization in microplates suitable for cell culture adapted to the lyophilizer, and subsequently verified the preservation of the antigenicity of the vaccine through the ELISA test. Statistical analysis was performed using SPSS® v.17, applying regression analysis for categorical data. Arginine 0.5%, PEG 3350 0.5%, Sucrose 2%, Maltose 1% and Trehalose 1% were those that gave better results, a high score of antigenicity compared to the lyophilized vaccine with no added excipients. The temperature of collapse of VRI and its various formulations was determined using a microscope coupled to a module of lyophilization. Thermal analysis was performed in Differential Scanning Calorimetry (DSC). The following tests were used for evaluation of freeze-dried VRI: Scanning electron microscopy (SEM), Antibody-binding test (ABT). The residual moisture of lyophilized samples were determined in the moisture analyzer at constant temperature of 100 °C and resulted in 1.60%. The cake of lyophilized rabies vaccine + 0.5% PEG 3350 in vial showed the pharmaceutical elegance expected of a lyophilized product.
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Produção, liofilização, purificação e determinação de especificidade da peptidase isolada do fungo Scopulariopsis koningii / Production, freeze drying, purification and determination of specific peptidase isolated from the fungus Scopulariopsis koningiiGabriel Tescarolo Giovanini 23 May 2014 (has links)
Peptidase pode ser considerada, como uma subclasse das enzimas hidrolíticas que ocupam uma posição central em relação às suas aplicações na área fisiológica e também na área comercial. As peptidases representam um dos três maiores grupos de enzimas industriais e são responsáveis por cerca de 60% da venda mundial de enzimas. O presente trabalho visa avaliar a produção de peptidase em fermentação submersa (FSm) pelo fungo Scopulariopsis koningii, utilizando como substrato farinha de pena (FP), a caracterização bioquímica parcial, secagem do extrato bruto, purificação da peptidase e determinação de especificidade da peptidase isolada. Para avaliar a influência da farinha de pena (FP), na produção de peptidases, foram adicionadas às porcentagens de 0,2; 0,4 e 0,8% no meio de cultura. Os melhores níveis de produção de peptidases pelo fungo Scopulariopsis koningii foram obtidos nas concentrações de 0,4% e 0,8% de FP em 48h de fermentação com 1.427 U/mL. A caracterização bioquímica parcial do extrato bruto foi realizada com azocaseína 1% preparada em tampão com pH adequado. A peptidase presente no extrato enzimático apresentou atividade ótima em pH 6,5 e temperatura ótima de 55°C. A peptidase foi inibida por PMSF, indicando a presença de resíduo de aminoácido serino no sítio catalítco, e desta forma sendo classificada como serino peptidase. Entretanto, também observamos uma inibição por EDTA, sugerindo a presença de uma metalo peptidase presente no extrato bruto, desta forma podemos sugerir que o fungo S. koningii na presença do meio contendo FP secreta duas subclasses; serino e metalo peptidase, ou secreta uma serino peptidase dependente de íon. Zimograma constatou a presença de duas enzimas. A atividade enzimática do extrato bruto diminuiu significativamente quando exposta os íons Al+3, Ni2+ e Cu2+ e aumentada quando adicionados os íons Ba2+, Ca2+ e Mg2+. A purificação da metalo peptidase presente no extrato enzimático envolveu sete etapas de purificação, sendo cromatografia de troca-iônica e gel filtração determinantes, com recuperação de 6% e purificação de 3,4 vezes. Utilizando a peptidase pura (metalo) realizouse a caracterização bioquímica funcional e a determinação dos parâmetros cinéticos, ambos utilizando o substrato peptídico de supressão intramolecular de fluorescência. A peptidase pura apresentou atividade ótima em pH 6,0 e temperatura ótima de 40°C e mostrou-se estável em ampla faixa de pH e temperatura. Foi modulada positivamente pelos íons Na+ e K+ e negativamente por Al3+ e Cu2+. A análise dos parâmetros cinéticos revelou uma grande influência de aminoácidos apolares do lado \"linha\" do substrato sintético na eficiência catalítica e no lado não \"linha\" grande influência de aminoácidos polares neutros e apolares. A secagem foi realizada por liofilização foram utilizados três tipos de adjuvantes: maltodextrina, manitol e glicina, em diferentes concentrações. Após a secagem foi realizado estudo da estabilidade nas temperaturas 4, 25 e 60°C por 32 dias para avaliar o desempenho dos adjuvantes na manutenção da atividade do extrato enzimático liofilizado. O adjuvante considerado mais eficaz foi a maltodextrina na concentração de 4,5% que manteve cerca de 93% da atividade do extrato enzimático liofilizado por 32 dias. / Peptidase can be considered as a subclass of hydrolytic enzymes which occupy a central position in relation to their applications in physiological area and also in the commercial area. Peptidases represent one of the three largest groups of industrial enzymes and account for about 60% of worldwide sales of enzymes. This study aims to evaluate the production of peptidase in submerged fermentation (FSm) by the fungus Scopulariopsis koningii, using as substrate feather meal (FP), the partial biochemical characterization, drying the crude extract, purification and determination of specific peptidase peptidase isolated. To evaluate the influence of feather meal (FM), in the production of peptidases, were added to the percentages of 0.2, 0.4 and 0.8% in the culture medium. The best levels of production of peptidases by the fungus Scopulariopsis koningii were obtained at concentrations of 0.4% and 0.8% of FP 48h fermentation with 1,427 U/mL. Partial biochemical characterization of the crude extract was performed with 1% azocasein prepared in buffer with appropriate pH. This in peptidase enzyme extract showed optimal activity at pH 6.5 and optimum temperature of 55°C. The peptidase was inhibited by PMSF, indicating the presence of a serine residue at amino acid catalytic site, and thus being classified as serine peptidase. However, we also observed an inhibition by EDTA, suggesting the presence of a metallo peptidase present in the crude extract, thus we suggest that the fungus S. koningii in the presence of medium containing secret FP two subclasses; serine peptidase and metal, or secretes a serine peptidase dependent ion. Zymogram found the presence of two enzymes. The enzymatic activity of the crude extract decreased significantly when exposed the Al 3+, Ni 2+ and Cu2+ ions and increased when added to Ba2+, Ca2+ and Mg2+ ions. The purification of metallo peptidase present in the enzyme extract involved seven stages of purification, and ion-exchange chromatography and gel filtration determinants, with recovery and purification of 6 % from 3.4 times. Using pure peptidase (metallo) held functional biochemical characterization and determination of kinetic parameters using both the intramolecular peptide substrate fluorescence suppression. Pure peptidase showed optimal activity at pH 6.0 and optimum temperature of 40°C and was stable in a wide range of pH and temperature. The positively modulated by Na+ and K+ and negatively by Al3+ and Cu2+. Analysis of kinetic parameters revealed a strong influence of nonpolar amino acid side \"line\" of the synthetic substrate in the catalytic efficiency and not on the side \"line\" great influence of nonpolar and polar neutral amino acids. The freeze drying was performed by three types of additives were used: maltodextrin, mannitol and glycine in different concentrations. After drying stability study was conducted at the temperatures 4, 25 and 60°C for 32 days to evaluate the performance of additives in maintaining the activity of the enzyme extract lyophilized. The adjuvant was found more efficacious maltodextrin in a concentration of 4.5%, which retained about 93% of the extract lyophilized enzyme activity for 32 days.
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Estratégias do processo para a conservação da potência da vacina rábica de uso veterinário por liofilização / Strategies of the process for the conservation of the potency of rabies vaccine for veterinary use by lyophilizationAline Tojeira Prestia Caricati 11 April 2012 (has links)
Uma vacina liofilizada, em comparação a uma líquida, possui inúmeras vantagens, tais como: a melhora na estabilidade do produto às variações de temperatura aumentando sua vida de prateleira, possibilitando uma melhor logística do produto aos locais onde o acesso à rede refrigerada é difícil. O presente trabalho visou investigar as estratégias do processo para a conservação da potência da vacina rábica de uso veterinário por liofilização. O material testado foi a vacina rábica inativada (VRI). Ao total foram testados 13 excipientes com três concentrações diferentes. O processo de triagem utilizado para a escolha das melhores formulações (VRI + excipiente) foi liofilização em microplacas próprias para cultivo celular adaptadas ao liofilizador, sendo posteriormente verificada a preservação da antigenicidade da vacina por meio do teste de ELISA. A análise estatística foi realizada no programa SPSS® v.17, aplicando análise de regressão para dados categóricos. A arginina 0,5%, o PEG 3350 0,5%, a sacarose 2%, a maltose 1% e a trealose 1% foram os que deram melhores resultados, um alto \"score\" de antigenicidade em comparação à vacina liofilizada sem adição de excipientes. A temperatura de colapso da VRI e de suas diversas formulações foi determinada por meio de um microscópio acoplado a um módulo de liofilização. A análise térmica foi realizada em Calorimetria Exploratória Diferencial (Differential Scanning Calorimetry - DSC). Realizou-se os seguintes testes para avaliação da VRI liofilizada em frasco ampola: microscopia eletrônica de varredura (MEV) para análise da estrutura da pastilha e o antibody-binding test (ABT) - Teste de ligação do anticorpo modificado para determinação da potência da VRI e suas formulações. A umidade residual da VRI com PEG3350 0,5% liofilizada foi determinada em temperatura constante de 100ºC resultou em 1,60%. A pastilha da vacina rábica + PEG 3350 0,5% liofilizada em frasco ampola apresentou a elegância farmacêutica esperada de um produto liofilizado. / A lyophilized vaccine, compared to a liquid form, has many advantages, such as the improvement in product stability to changes in temperature by increasing its shelf life, allowing better logistics for product to locations where access to chill is difficult to achieve. This work has investigated the strategies of the process for the conservation of the potency of rabies vaccine for veterinary use by lyophilization. The material tested is an inactivated rabies vaccine (VRI). Altogether 13 excipients were tested with three different concentrations. The screening process used to choose best formulation (s) (VRI + excipient) was lyophilization in microplates suitable for cell culture adapted to the lyophilizer, and subsequently verified the preservation of the antigenicity of the vaccine through the ELISA test. Statistical analysis was performed using SPSS® v.17, applying regression analysis for categorical data. Arginine 0.5%, PEG 3350 0.5%, Sucrose 2%, Maltose 1% and Trehalose 1% were those that gave better results, a high score of antigenicity compared to the lyophilized vaccine with no added excipients. The temperature of collapse of VRI and its various formulations was determined using a microscope coupled to a module of lyophilization. Thermal analysis was performed in Differential Scanning Calorimetry (DSC). The following tests were used for evaluation of freeze-dried VRI: Scanning electron microscopy (SEM), Antibody-binding test (ABT). The residual moisture of lyophilized samples were determined in the moisture analyzer at constant temperature of 100 °C and resulted in 1.60%. The cake of lyophilized rabies vaccine + 0.5% PEG 3350 in vial showed the pharmaceutical elegance expected of a lyophilized product.
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Resposta imune do antígeno de superfície de hepatite B administrado via nasal em nanopartículas de quitosana liofilizadas / Immune response to hepatitis B surface antigen administered nasally in freeze-dried chitosan nanoparticles.Richard Saldaña Gonzales 18 February 2016 (has links)
A nanotecnologia tornou possível estruturar nanopartículas (NPs), utilizando-se polímeros biodegradáveis e atóxicos, como a quitosana (QS) - capaz de carrear e disponibilizar antígenos para a mucosa, devido sua propriedade mucoadesiva. Uma vacina liofilizada, em comparação a uma formulação líquida, possui inúmeras vantagens, tais como melhora na estabilidade do produto e melhor resistência às variações de temperatura, aumentando sua vida de prateleira e possibilitando melhor logística do produto aos locais onde o acesso à rede refrigerada é difícil; ademais, um produto liofilizado tem sua mucoadesividade aumentada, possibilitando maior tempo de permanência na mucosa. O presente trabalho teve como objetivo observar a resposta imune, em camundongos, de uma vacina desenvolvida por um mecanismo de entrega intranasal do HBsAg (Antígeno de superfície da Hepatite B) encapsulado pelo método de incorporação em nanopartículas de quitosana (NPs) liofilizadas. A formação das NPs foi realizada pela interação eletroestática da quitosana e do TPP (tripolifosfato de sódio), utilizando método de geleificação iônica. Formulações de NPs com glicina 5% apresentaram boas características após reconstituição, umidade residual inferior a 1% e processo de liofilização de 13 horas. Foi avaliada a imunogenicidade da inoculação do HBsAg em formulações de NPs de quitosana líquida e liofilizada, verificando-se que a forma líquida produziu anticorpos IgG contra HBsAg. / Nanotechnology has become possible to structure nanoparticles (NPs), using non-toxic and biodegradable polymers such as chitosan (CS), capable of carrying and deliver antigens to the mucosa, due to mucoadhesive property. A lyophilized vaccine compared to a liquid formulation, has several advantages, such as improved product stability as well as better resistance to temperature changes, increasing its shelf life allowing better logistics of the product to places where access to the chain cold is difficult and especially a lyophilized product increases muco-adhesiveness providing for longer staying in the mucosa. The work aims to observe the immune response in mice of vaccine developed by an intranasal delivery mechanism of HBsAg (hepatitis B surface antigen) encapsulated by incorporation method in chitosan nanoparticles (NPs) lyophilized. The formation of NPs was performed by electrostatic interaction between the chitosan and TPP (sodium tripolyphosphate) using the ionic gelation. Formulations showed good characteristics after reconstitution, residual humidity lower than 1% and the lyophilization process 15-hour. In this work, was evaluated the immunogenicity of inoculation of HBsAg in lyophilized and liquid formulations of chitosan nanoparticles, which liquid formulation produced anti-HBsAg antibodies.
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Διερεύνηση των συνθηκών που απαιτούνται για σταθεροποίηση λιποσωμάτων DRV που εγκλωβίζουν υψηλές ποσότητες πρωτεϊνών μετά από λυοφιλοποίηση, ώστε να μπορούν να αποθηκεύονται σε ξηρή μορφήΝτυμένου, Βασιλική Π. 11 February 2009 (has links)
Η λυοφιλοποίηση θεωρείται ιδανική μέθοδος για βραχύχρονη ή/ και μακρόχρονη αποθήκευση λιποσωμάτων. Στόχος αυτής της μελέτης ήταν να ευρεθούν οι ποσότητες κρυοπροστατευτικού που μπορεί να αυξήσουν τη συγκράτηση πρωτεϊνικών μορίων σε λιποσώματα τα οποία είναι ασταθή (δηλ. χάνουν μεγάλο τμήμα της εγκλωβισμένης πρωτεΐνης) μετά από λυοφιλοποίηση. Η μέθοδος παρασκευής των λιποσωμάτων που χρησιμοποιήθηκε ήταν η DRV μέθοδος. Είναι η πλέον κατάλληλη στην περίπτωση εγκλωβισμού πρωτεϊνικών μορίων καθώς επιτυγχάνει υψηλά ποσοστά εγκλωβισμού και επίσης χρησιμοποιεί ήπιες συνθήκες οπότε προστατεύεται η τριτοταγής δομή των πρωτεϊνών. Η διαδικασία βασίζεται στην αφυδάτωση μίγματος “άδειων” SUV (μικρών μονοστοιβαδιακών) λιποσωμάτων παρουσία του διαλύματος πρωτεΐνης που πρόκειται να εγκλωβιστεί. Μετά από ελεγχόμενη επανενυδάτωση της ξηρής κόνης σχηματίζονται τα DRV λιποσώματα. (από τις λέξεις dried-rehydrated vesicles που μεταφράζονται ως αφυδατωμένα-επανενυδατωμένα σωματίδια).
Ως υλικά για την παρασκευή των λιποσωμάτων χρησιμοποιήθηκαν τα εξής: Φωσφατιδυλοχολίνη αυγού (egg PC), διστεαροϋλο-γλυκεροφωσφατιδυλοχολίνη (DSPC), διπαλμιτοϋλο-γλυκεροφωσφατιδυλοχολίνη (DPPC), διμυριστοϋλο-γλυκεροφωσφατιδυλοχολίνη (DΜPC), φωσφατιδυλογλυκερόλη (PG) και χοληστερόλη (CHOL).
Παρασκευάστηκαν με τη μέθοδο DRV λιποσώματα διαφόρων λιποσωμικών συστάσεων προκειμένου να μελετηθεί η ικανότητα εγκλωβισμού για κάθε λιποσωμική σύσταση και να επιλεγούν αυτές που είναι πλέον ασταθείς για περαιτέρω μελέτη. Ως πρωτεΐνη μοντέλο χρησιμοποιήθηκε η αλβουμίνη βόειου ορού (BSA).
Μελετήθηκε η επίδραση της λυοφιλοποίησης σε διάφορα DRV λιποσώματα παρουσία ή/ και απουσία κρυοπροστατευτικού παράγοντα (τρεαλόζη). Σε κάποιες περιπτώσεις προστέθηκε τρεαλόζη εντός των λιποσωμάτων κατά την αρχική παρασκευή των DRV (στο στάδιο της ανασύστασης).
Επίσης, προκειμένου να αποκτήσουμε περαιτέρω πληροφορίες για τα λιποσώματα που μελετούσαμε, πραγματοποιήθηκε προσδιορισμός του μεγέθους των ορισμένων λιποσωμικών σειρών και μορφολογική μελέτη με ηλεκτρονικό μικροσκόπιο σάρωσης.
Στη συνέχεια, με βάση τα αρχικά αποτελέσματα με την αλβουμίνη, επιλέχθηκαν ορισμένες λιποσωμικές συστάσεις προκειμένου να μελετηθεί η σταθερότητα λιποσωμάτων που εγκλωβίζουν ένα βιοδραστικό μόριο, το t-PA (ιστικού τύπου ενεργοποιητή πλασμινογόνου) σε ξηρή μορφή. Η μελέτη πραγματοποιήθηκε με δείκτη τη διατήρηση της ενεργότητας του μορίου μετά από FD και προσθήκη ή όχι τρεαλόζης.
Απώτερος σκοπός αυτής της εργασίας είναι η δυνατότητα παρασκευής σταθερών t-PA- λιποσωμικών μορφών σε ξηρή μορφή προκειμένου να μελετηθεί η δράση τους στη θεραπεία θρομβώσεων του αμφιβληστροειδούς.
Τα βασικά συμπεράσματα της μελέτης είναι τα εξής:
Σχετικά με αποτελέσματα πειραμάτων με BSA:
* Τα PC:PG:CHOL DRV λιποσώματα σταθεροποιούνται ικανοποιητικά αν πριν τη λυοφιλοποίηση προσθέσουμε αναλογία treh/lipid=5/1 στη λιποσωμική διασπορά.
* Η καλύτερη σταθεροποίηση επιτυγχάνεται με παρουσία σακχάρου στο εσωτερικό και εξωτερικό των λιποσωμάτων
* Πιθανή αλληλεπίδραση λαμβάνει χώρα μεταξύ των PC λιποσωμάτων και της αλβουμίνης, δίνοντας ψευδή υψηλά τελικά ποσοστά συγκράτησης μετά τη λυοφιλοποίηση
Σχετικά με αποτελέσματα πειραμάτων με t-PA
* Τα αποτελούμενα από DSPC DRV λιποσώματα παραμένουν πολύ σταθερά διατηρώντας την ενεργότητα του t-PA μετά τη λυοφιλοποίηση και χωρίς την προσθήκη κρυοπροστατευτικού.
* Τα ασταθή PC:PG:CHOL και PC λιποσώματα σταθεροποιούνται ικανοποιητικά με προσθήκη τρεαλόζης πριν το FD. / Lyophilization is considered to be an ideal technique for both short-term and long-term storage of liposomes. The objective of this study was to investigate the stability of liposomes encapsulating protein molecules and the effect of freeze-drying (FD) on the stability of dehydrated-rehydrated vesicles (DRV) with and without cryoprotective agents (CPA). Τhe liposomes were prepared by the DRV method. This is considered to be the most appropriate in the cases that entrapment of proteins is desired, since it gives liposomes with high encapsulation efficiencies and by using mild conditions it protects the tertiary structure of proteins retaining thus their biological activity. The procedure followed here was based on dehydration of a mixture of “empty” SUV liposomes and the protein solution (BSA) which is to be entrapped, followed by controlled rehydration of the dry powder.
The materials used for the preparation of the liposomes were:
Egg-PC (phosphatidylcholine), distearoyloglycerophosphatidylcholine(DSPC), (DPPC) dipalmitoylglycerophosphatidylcholine, (DΜPC) dimyristoylglycerophosphatidylcholine, PG (phosphatidylglycerol) and CHOL (cholesterol).
Liposomes of various lipid compositions were prepared so that the most unstable liposome compositions are found and available for further study. BSA was used as a protein model in these experiments.
Furthermore, the influence of lyophilization for liposomes of various compositions was studied using trehalose as a cryoprotective agent. In some experiments, the dissacharide was added during the reconstitution of DRV.
In order to have some more information about the liposomes under investigation, we conducted particle size determination (zetasizer) and morphological study by SEM (scanning electron microscopy.
Eventually, based on the primary results with albumin, the stability of liposomes bearing a bioactive protein was studied. The protein used here was t-PA (tissue type plasminogen activator). We investigated the influence of FD on the stability of liposomes with or without the addition of a cryoprotective agent (trehalose) as a function of bioactivity retention.
A long-term objective of our studies is to prepare stable after FD liposomal- tPA-formulations that may be active for therapy of ocular thrombosis cases.
The mail conclusions of this study were:
Concerning the results obtained with BSA:
* PC:PG:CHOL DRV liposomes are adequately stabilized when trehalose in mass ratio treh/PC=5/1 is added in the liposomal dispersion
* Maximum retention of BSA is achieved when trehalose is added on both sides of liposomal membrane.
* There is a possible interaction between BSA and PC liposomes, which results in false estimation of BSA retention after FD.
Concerning the results obtained with t-PA:
* DSPC DRV liposomes are very stable after FD and they preserve t-PA activity even in absence of cryoprotectant.
* Unstable PC:PG:CHOL and PC liposomes can be adequately stabilized by trehalose.
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