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Effect of Storage Humidity on Physical Stability and Aerosol Performance of Spray-Dried Dry Powder Inhaler FormulationsNivedita J Shetty (6955364) 15 August 2019 (has links)
<p>Dry Powder inhalers (DPIs) have
been one of the most promising developments in pulmonary drug delivery systems.
In general, DPIs are more effective than systemic administrations and convenient
to use. However, delivering high-dose antibiotics through a DPI is still a
challenge because high powder load may need a very large inhaler or increase
the incidence of local adverse effects. Spray drying has been increasingly
applied to produce DPI formulations for high-dose antibiotics; nevertheless,
many spray-dried particles are amorphous and physically unstable during
storage, particularly under the humid environment. </p>
<p> </p>
<p>My research focuses on addressing
critical challenges in physical stability of DPIs for spray-dried high-dose
antibiotics. The effects of moisture-induced crystallization on physical
stability and aerosol performance of spray-dried amorphous Ciprofloxacin DPI
formulations stored at different humidity conditions were studied. Our study
not only provided a mechanistic understanding in the impact of crystallization
on aerosol performance but also developed novel approaches for improving
stability of spray-dried formulations used in DPI.</p>
<p> </p>
<p>Our work has shown that
recrystallization of amorphous spray-dried Ciprofloxacin led to significant
changes in aerosol performance of DPIs upon storage, which cause critical
quality and safety concerns. These challenges have been solved through co-spray-drying
Ciprofloxacin with either excipient such as leucine or synergistic antibiotic
like Colistin. Co-spray-drying Ciprofloxacin with Colistin not only improved
physical and aerosol stability but also enhanced antibacterial activity which
is a great advantage for treating ‘difficult to cure’ respiratory infections
caused by multidrug resistant bacteria.</p>
<p> </p>
<p>My research work is a sincere
effort to maximize the utility and efficacy of high-dose DPI, an effective
delivery tool for treating severe resistant bacterial respiratory infections.</p>
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Rapid preformulation screening of drug candidates for dry powder inhaler preparationHarris, Haggis January 2008 (has links)
Candidate active pharmaceutical ingredients (APIs) are routinely tested to determine such parameters as physical stability, chemical stability, and bioavailability. Preformulation analysis of APIs does not currently attemept to determine whether they will perform to an acceptable level once they have been formulated. In practice, the APIs are subjected to extensive in vitro testing of their performance in a formulation, combined with optimisation of the formulation. This formulation testing is both time-consuming and expensive. In the field of pulmonary drug delivery from dry powder inhalers (DPIs), the API has to be aerosolized effectively in order to penetrate the lunfs and reach its deposition target. In a conventional ternary DPI fromulation, the API is combined with carrier lactose and fine lactose particles. The inter-particle forces between these three components and the bulk properties of the formulation determine the structure of the formulation and the aerolization performance of the API. In this study, physicochemical properties of salbutamol base and several of its salts were investigated both quantitatively and qualitatively. The in vitro deposition characteristics of the formulated APIs were also determined. The relationship between these parameters and the deposition was analysed to establish if a rapid preformulation screening technique could be applied to the APIs with respect to predicting the deposition performance of the formulated API. A clear relationship between the deposition of the unformulated API and the formulated API was observed that could be exploited as a screening technique.
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An investigation into the dispersion mechanisms of ternary dry powder inhaler formulations by the quantification of interparticulate forcesJones, Matthew D. January 2006 (has links)
No description available.
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Dry Powders Inhalers (DPI) obtidos a partir de nanocápsulas de núcleo lipídico contendo budesonida : caracterização, avaliação in vivo em modelo animal de asma e da toxicidade in vitro em cultura celularOrtiz, Manoel January 2016 (has links)
A asma é definida como uma doença inflamatória crônica de caráter multifatorial, caracterizada pela obstrução reversível das vias aéreas, denso infiltrado inflamatório e hiper-reatividade brônquica a estímulos externos. Clinicamente, a doença é marcada por sintomas episódicos de dispneia, sibilo, tosse seca e sensação de aperto no peito. A terapia convencional da asma compreende o uso de anti-inflamatórios e broncodilatadores. A budesonida é um glicocorticoide esteroide e é dos fármacos mais utilizados na terapêutica da asma. No entanto, a budesonida apresenta baixa biodisponibilidade oral e o uso prolongado pode levar a efeitos adversos graves como afinamento da pele e supressão adrenocortical. No desenvolvimento de novas formulações, a avaliação da toxicidade é de extrema importância. Por conseguinte, o uso de cultura celular é de grande valia no desenvolvimento de protocolos para avaliação da toxicidade de novas formulações. Adicionalmente, a nanotecnologia é uma ferramenta importante para resolver problemas de biodisponibilidade e para contornar efeitos adversos da terapêutica convencional. Desta forma, o objetivo desta tese foi desenvolver um novo sistema nanoestruturado na forma de pó seco para inalação (Dry powders inhalers – DPI), obtido por aspersão contendo budesonida encapsulada, visando o tratamento da asma aguda e crônica. Essa proposta foi baseada na obtenção de um sistema pulverulento nanoestruturado com tamanho reduzido e controlado, visando a entrega pulmonar da budesonida. Na etapa de pré-formulação foi realizado um estudo fatorial avaliando diferentes métodos de preparação das nanocápsulas e os adjuvantes de secagem utilizados. As análises de tamanho de partícula, da formulação selecionada (nanocápsulas contendo budesonida e secas por aspersão com leucina) mostraram um tamanho reduzido e adequado para a administração pulmonar (2,7 μm). A morfologia demonstrou que estas partículas possuem um tamanho reduzido, forma esférica e superfície irregular, características importantes para a administração pulmonar. Quando analisada a distribuição pulmonar in vitro, em Impactador de Andersen, a formulação apresentou uma fração de partículas finas (Fine Particle Fraction – FPF) de 28%. Analisando os resultados dos experimentos em modelos de asma aguda e crônica induzidos por ovalbumina, os resultados da mecânica respiratória e função pulmonar mostraram uma diminuição na resistência e na elastância pulmonar, quando a budesonida nanoencapsulada foi utilizada, quando comparada com uma formulação comercial de budesonida, nas duas doses utilizadas (0,5 e 1,0 mg/Kg). Esse tratamento com nanocápsulas também mostrou eficiência na redução da inflamação, pela redução do número de leucócitos totais no fluido de lavagem bronco alveolar (Broncho Alveolar Lavage Fluid – BALF) e, principalmente, redução significativa no número dos eosinófilos no infiltrado pulmonar. Corroborando esses resultados, a quantificação da eotaxina – 1 e das citocinas pró-inflamatórias foram reduzidas, quando comparadas ao tratamento comercial. A análise histopatológica mostrou que quando o tratamento com as nanocápsulas foi utilizado, a produção de muco foi reduzida, bem como a produção de fibrose sub-epitelial, sugerindo um possível efeito sobre o remodelamento tecidual. Os resultados de toxicidade utilizando linhagem celular epitelial pulmonar (H441) mostrou uma redução na toxicidade da budesonida, quando encapsulada nas nanopartículas, tanto na forma de suspensão como na forma pulverulenta. Essa redução da toxicidade foi de 75% e de 50%, na dose de 100 μg/mL, para a suspensão e para o DPI, respectivamente. O conjunto dos resultados obtidos mostrou a potencial aplicabilidade da budesonida nanoencapsulada para o tratamento da asma, utilizando esse novo sistema DPI. / Asthma is characterized as a chronic inflammatory disease developed by multifactorial aspects such as genetic predisposition and exposure to environmental factors such as pollution, smoke and microorganisms. The conventional asthma therapy comprises the use of bronchodilators and anti-inflammatory. Budesonide is a glucocorticoid and is the most frequently used therapy in the treatment of asthma. However, this drug has low oral bioavailability and long term use may lead to adverse effects such as skin thinning and adrenal suppression. The evaluation of the toxicity of new formulation has critical role in the pharmaceutical development. The use of cell culture experiments can help this aspect. Additionally, nanotechnology is an important tool to solve problems regarding bioavailability and to circumvent adverse effects of conventional therapy. The aim of this work was to develop a nanostructured system as dry powder inhaler (DPI) containing budesonide loaded, obtained by spray-drying, targeting the treatment of acute and chronic asthma. This proposal was based on obtaining a nanostructured powder system with reduced and controlled size, aiming an alternative to treatment of asthma. A factorial study comparing different methods to produce the nanocapsules as well as the type of drying adjuvants was performed. The particle size of the selected formulation was 2.7 μm, an adequate reduced size suitable for pulmonary administration. The morphology of these particles showed a small size, spherical shape and irregular surface. All these characteristics are important for pulmonary administration. When analyzed the in vitro pulmonary distribution of the DPI, using an Andersen Cascade Impactor, showed a fine particle fraction (FPF) of 28%. Analyzing the results of the biological experiments, the mechanical respiratory and pulmonary function showed a decrease in lung elastance and resistance when budesonide was used nanoencapsulated compared with a commercial formulation of budesonide in two doses (0.5 and 1.0 mg / kg). Both treatments also showed nanocapsules efficiency in reduction of inflammation by reducing the total of leukocytes in the bronchial alveolar lavage fluid (BALF) and especially significant reduction in eosinophil infiltration in the lung tissue. Corroborating with these results, the quantification of eotaxin - 1 and proinflammatory cytokines was reduced when compared to commercial budesonide treatment. Histopathological analysis showed that when treatment with the nanocapsules was used, mucus production was reduced and reversed the phenomena of airway remodeling. The cytotoxicity assay by Alamar blue using the bronchial epithelium cell line (H441) showed a reduction on the toxicity of budesonide when the nanocapsules were used even in suspension or in the DPI. The cytotoxicity reduction were 75 and 50%, at 100 μg/mL, for the suspension and the DPI, respectively. All these results show that budesonide-loaded nanocapsules in dry powder inhaler is a promising approach for the treatment of asthma.
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Pulmonary delivery of brittle matrix powders produced by thin film freezingWang, Yi-Bo 03 March 2015 (has links)
Recently, the portfolio of compounds approved for inhalation therapy has expanded rapidly for lung disease therapies. The rationale for this delivery approach includes a more targeted and localized delivery to the diseased site with reduced systemic exposure, potentially leading to decreased adverse side effects. We have proposed that brittle matrix powders prepared by thin film freezing (TFF) are a suitable platform for pulmonary drug delivery which can achieve high lung concentrations while limit the corresponding systemic levels associated with toxicity, and enhanced physicochemical and aerodynamic properties can be obtained by varying TFF processing parameters. In Chapter 2, the in vitro and in vivo performance of an amorphous formulation prepared by TFF and a crystalline micronized formulation produced by milling was compared for Tacrolimus (TAC). TFF processed matrix powders was capable of achieving deep lung delivery due to its low density, highly porous and brittle characteristics. When emitted from a Miat® monodose inhaler, TFF processed TAC formulations exhibited a fine particle fraction (FPF) of 83.3% and a mass median aerodynamic diameter (MMAD) of 2.26 µm. Single dose 24-h pharmacokinetic studies in rats demonstrated that the TAC formulation prepared by TFF exhibited higher pulmonary bioavailability with a prolonged retention time in the lung, possibly due to decreased clearance (e.g., macrophage phagocytosis), compared to the micronized TAC formulation. Additionally, TFF formulation generated a lower systemic TAC concentration with smaller variability than the micronized formulation following inhalation, potentially leading to reduced side effects related to the drug in systemic circulation. Chapter 3 investigated the impact of processing parameters in the TFF process on the physicochemical and aerodynamic properties of the resulting formulations. All of these enhanced powder properties resulted from higher freezing rate contributed to a better aerodynamic performance of the obtaining formulations. Moreover, a decreasing trend of FPF was observed for these TFF powders when the initial solid concentrations increased. The variation of the freezing rate and initial solid loading in the TFF process enabled the production of formulations with enhanced physicochemical properties and improved aerodynamic performance. / text
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Dry powder antibiotics for inhaled anti-tuberculosis therapySon, Yoen Ju 09 February 2011 (has links)
The aim of this research was to develop and fully investigate a novel method of antibiotic drug delivery to the lung that will address problems with current therapeutic regimens for treatment of airway infections. To demonstrate the performance of prepared formulations, the design of suitable characterization methods were also aimed. A novel dissolution method for evaluating the in vitro dissolution behavior of inhalation formulations was developed. The membrane holder was designed to enclose previously air-classified formulations so that they could be uniformly tested in the dissolution apparatus. Dissolution procedures, the apparatus, the dose collection, the medium, and test conditions were developed and the dissolution behaviors of test compounds were evaluated by experimental and mathematical analysis. It was proved that the aerodynamic separation of formulation prior to dissolution assessment have a significant influence on the dissolution profiles. The optimized test method using the membrane holder was applied to evaluate in vitro dissolution profiles of the manufactured formulations of rifampicin (RF). The carrier/excipient-free RF dry powder formulation was investigated. The rifampicin dihydrate (RFDH) powders having MMAD of 2.2 um were prepared using a simple recrystallization process. The RFDH powders have a thin flaky structure, and this unique morphology provides improved aerosolization properties at maximal API loading. The manufactured RFDH formulation showed 80% drug release within 2 hours. To retard the release rate of RF, the prepared RFDH crystals were coated with hydrophobic polymer, PLA or PLGA, using spray-dryer equipped with multi-channel spray nozzles. The multi-channel spray nozzle used in this study has two separate nozzles for aqueous solution and one for gas fluid. The RFDH crystals and the coating solutions were sprayed through the two separate liquid nozzles at the same time. The coated RFDH formulations were prepared using multi-channel spray nozzles. The coated formulations contained at least 50% w/w of RF with no change of their flaky morphology. The initial RF release was lowered by coating; the lowest initial RF release was observed from the coated powders with PLA polymer as 32% among the coated formulations. Overall, the 80% of RF was released within 8 hours. The RFDH and coated RFDH formulations delivered via the pulmonary route would be anticipated to provide higher local (lung) drug concentrations than that of orally delivered powders. Particularly, the coated RFDH powders deposited in the alveolar region may prolong the drug residence time in the site of infections. Additionally, it was proved that the RFDH and coated RFDH formulations provided much better stability than the amorphous RF. / text
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Dry Powders Inhalers (DPI) obtidos a partir de nanocápsulas de núcleo lipídico contendo budesonida : caracterização, avaliação in vivo em modelo animal de asma e da toxicidade in vitro em cultura celularOrtiz, Manoel January 2016 (has links)
A asma é definida como uma doença inflamatória crônica de caráter multifatorial, caracterizada pela obstrução reversível das vias aéreas, denso infiltrado inflamatório e hiper-reatividade brônquica a estímulos externos. Clinicamente, a doença é marcada por sintomas episódicos de dispneia, sibilo, tosse seca e sensação de aperto no peito. A terapia convencional da asma compreende o uso de anti-inflamatórios e broncodilatadores. A budesonida é um glicocorticoide esteroide e é dos fármacos mais utilizados na terapêutica da asma. No entanto, a budesonida apresenta baixa biodisponibilidade oral e o uso prolongado pode levar a efeitos adversos graves como afinamento da pele e supressão adrenocortical. No desenvolvimento de novas formulações, a avaliação da toxicidade é de extrema importância. Por conseguinte, o uso de cultura celular é de grande valia no desenvolvimento de protocolos para avaliação da toxicidade de novas formulações. Adicionalmente, a nanotecnologia é uma ferramenta importante para resolver problemas de biodisponibilidade e para contornar efeitos adversos da terapêutica convencional. Desta forma, o objetivo desta tese foi desenvolver um novo sistema nanoestruturado na forma de pó seco para inalação (Dry powders inhalers – DPI), obtido por aspersão contendo budesonida encapsulada, visando o tratamento da asma aguda e crônica. Essa proposta foi baseada na obtenção de um sistema pulverulento nanoestruturado com tamanho reduzido e controlado, visando a entrega pulmonar da budesonida. Na etapa de pré-formulação foi realizado um estudo fatorial avaliando diferentes métodos de preparação das nanocápsulas e os adjuvantes de secagem utilizados. As análises de tamanho de partícula, da formulação selecionada (nanocápsulas contendo budesonida e secas por aspersão com leucina) mostraram um tamanho reduzido e adequado para a administração pulmonar (2,7 μm). A morfologia demonstrou que estas partículas possuem um tamanho reduzido, forma esférica e superfície irregular, características importantes para a administração pulmonar. Quando analisada a distribuição pulmonar in vitro, em Impactador de Andersen, a formulação apresentou uma fração de partículas finas (Fine Particle Fraction – FPF) de 28%. Analisando os resultados dos experimentos em modelos de asma aguda e crônica induzidos por ovalbumina, os resultados da mecânica respiratória e função pulmonar mostraram uma diminuição na resistência e na elastância pulmonar, quando a budesonida nanoencapsulada foi utilizada, quando comparada com uma formulação comercial de budesonida, nas duas doses utilizadas (0,5 e 1,0 mg/Kg). Esse tratamento com nanocápsulas também mostrou eficiência na redução da inflamação, pela redução do número de leucócitos totais no fluido de lavagem bronco alveolar (Broncho Alveolar Lavage Fluid – BALF) e, principalmente, redução significativa no número dos eosinófilos no infiltrado pulmonar. Corroborando esses resultados, a quantificação da eotaxina – 1 e das citocinas pró-inflamatórias foram reduzidas, quando comparadas ao tratamento comercial. A análise histopatológica mostrou que quando o tratamento com as nanocápsulas foi utilizado, a produção de muco foi reduzida, bem como a produção de fibrose sub-epitelial, sugerindo um possível efeito sobre o remodelamento tecidual. Os resultados de toxicidade utilizando linhagem celular epitelial pulmonar (H441) mostrou uma redução na toxicidade da budesonida, quando encapsulada nas nanopartículas, tanto na forma de suspensão como na forma pulverulenta. Essa redução da toxicidade foi de 75% e de 50%, na dose de 100 μg/mL, para a suspensão e para o DPI, respectivamente. O conjunto dos resultados obtidos mostrou a potencial aplicabilidade da budesonida nanoencapsulada para o tratamento da asma, utilizando esse novo sistema DPI. / Asthma is characterized as a chronic inflammatory disease developed by multifactorial aspects such as genetic predisposition and exposure to environmental factors such as pollution, smoke and microorganisms. The conventional asthma therapy comprises the use of bronchodilators and anti-inflammatory. Budesonide is a glucocorticoid and is the most frequently used therapy in the treatment of asthma. However, this drug has low oral bioavailability and long term use may lead to adverse effects such as skin thinning and adrenal suppression. The evaluation of the toxicity of new formulation has critical role in the pharmaceutical development. The use of cell culture experiments can help this aspect. Additionally, nanotechnology is an important tool to solve problems regarding bioavailability and to circumvent adverse effects of conventional therapy. The aim of this work was to develop a nanostructured system as dry powder inhaler (DPI) containing budesonide loaded, obtained by spray-drying, targeting the treatment of acute and chronic asthma. This proposal was based on obtaining a nanostructured powder system with reduced and controlled size, aiming an alternative to treatment of asthma. A factorial study comparing different methods to produce the nanocapsules as well as the type of drying adjuvants was performed. The particle size of the selected formulation was 2.7 μm, an adequate reduced size suitable for pulmonary administration. The morphology of these particles showed a small size, spherical shape and irregular surface. All these characteristics are important for pulmonary administration. When analyzed the in vitro pulmonary distribution of the DPI, using an Andersen Cascade Impactor, showed a fine particle fraction (FPF) of 28%. Analyzing the results of the biological experiments, the mechanical respiratory and pulmonary function showed a decrease in lung elastance and resistance when budesonide was used nanoencapsulated compared with a commercial formulation of budesonide in two doses (0.5 and 1.0 mg / kg). Both treatments also showed nanocapsules efficiency in reduction of inflammation by reducing the total of leukocytes in the bronchial alveolar lavage fluid (BALF) and especially significant reduction in eosinophil infiltration in the lung tissue. Corroborating with these results, the quantification of eotaxin - 1 and proinflammatory cytokines was reduced when compared to commercial budesonide treatment. Histopathological analysis showed that when treatment with the nanocapsules was used, mucus production was reduced and reversed the phenomena of airway remodeling. The cytotoxicity assay by Alamar blue using the bronchial epithelium cell line (H441) showed a reduction on the toxicity of budesonide when the nanocapsules were used even in suspension or in the DPI. The cytotoxicity reduction were 75 and 50%, at 100 μg/mL, for the suspension and the DPI, respectively. All these results show that budesonide-loaded nanocapsules in dry powder inhaler is a promising approach for the treatment of asthma.
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Dry Powders Inhalers (DPI) obtidos a partir de nanocápsulas de núcleo lipídico contendo budesonida : caracterização, avaliação in vivo em modelo animal de asma e da toxicidade in vitro em cultura celularOrtiz, Manoel January 2016 (has links)
A asma é definida como uma doença inflamatória crônica de caráter multifatorial, caracterizada pela obstrução reversível das vias aéreas, denso infiltrado inflamatório e hiper-reatividade brônquica a estímulos externos. Clinicamente, a doença é marcada por sintomas episódicos de dispneia, sibilo, tosse seca e sensação de aperto no peito. A terapia convencional da asma compreende o uso de anti-inflamatórios e broncodilatadores. A budesonida é um glicocorticoide esteroide e é dos fármacos mais utilizados na terapêutica da asma. No entanto, a budesonida apresenta baixa biodisponibilidade oral e o uso prolongado pode levar a efeitos adversos graves como afinamento da pele e supressão adrenocortical. No desenvolvimento de novas formulações, a avaliação da toxicidade é de extrema importância. Por conseguinte, o uso de cultura celular é de grande valia no desenvolvimento de protocolos para avaliação da toxicidade de novas formulações. Adicionalmente, a nanotecnologia é uma ferramenta importante para resolver problemas de biodisponibilidade e para contornar efeitos adversos da terapêutica convencional. Desta forma, o objetivo desta tese foi desenvolver um novo sistema nanoestruturado na forma de pó seco para inalação (Dry powders inhalers – DPI), obtido por aspersão contendo budesonida encapsulada, visando o tratamento da asma aguda e crônica. Essa proposta foi baseada na obtenção de um sistema pulverulento nanoestruturado com tamanho reduzido e controlado, visando a entrega pulmonar da budesonida. Na etapa de pré-formulação foi realizado um estudo fatorial avaliando diferentes métodos de preparação das nanocápsulas e os adjuvantes de secagem utilizados. As análises de tamanho de partícula, da formulação selecionada (nanocápsulas contendo budesonida e secas por aspersão com leucina) mostraram um tamanho reduzido e adequado para a administração pulmonar (2,7 μm). A morfologia demonstrou que estas partículas possuem um tamanho reduzido, forma esférica e superfície irregular, características importantes para a administração pulmonar. Quando analisada a distribuição pulmonar in vitro, em Impactador de Andersen, a formulação apresentou uma fração de partículas finas (Fine Particle Fraction – FPF) de 28%. Analisando os resultados dos experimentos em modelos de asma aguda e crônica induzidos por ovalbumina, os resultados da mecânica respiratória e função pulmonar mostraram uma diminuição na resistência e na elastância pulmonar, quando a budesonida nanoencapsulada foi utilizada, quando comparada com uma formulação comercial de budesonida, nas duas doses utilizadas (0,5 e 1,0 mg/Kg). Esse tratamento com nanocápsulas também mostrou eficiência na redução da inflamação, pela redução do número de leucócitos totais no fluido de lavagem bronco alveolar (Broncho Alveolar Lavage Fluid – BALF) e, principalmente, redução significativa no número dos eosinófilos no infiltrado pulmonar. Corroborando esses resultados, a quantificação da eotaxina – 1 e das citocinas pró-inflamatórias foram reduzidas, quando comparadas ao tratamento comercial. A análise histopatológica mostrou que quando o tratamento com as nanocápsulas foi utilizado, a produção de muco foi reduzida, bem como a produção de fibrose sub-epitelial, sugerindo um possível efeito sobre o remodelamento tecidual. Os resultados de toxicidade utilizando linhagem celular epitelial pulmonar (H441) mostrou uma redução na toxicidade da budesonida, quando encapsulada nas nanopartículas, tanto na forma de suspensão como na forma pulverulenta. Essa redução da toxicidade foi de 75% e de 50%, na dose de 100 μg/mL, para a suspensão e para o DPI, respectivamente. O conjunto dos resultados obtidos mostrou a potencial aplicabilidade da budesonida nanoencapsulada para o tratamento da asma, utilizando esse novo sistema DPI. / Asthma is characterized as a chronic inflammatory disease developed by multifactorial aspects such as genetic predisposition and exposure to environmental factors such as pollution, smoke and microorganisms. The conventional asthma therapy comprises the use of bronchodilators and anti-inflammatory. Budesonide is a glucocorticoid and is the most frequently used therapy in the treatment of asthma. However, this drug has low oral bioavailability and long term use may lead to adverse effects such as skin thinning and adrenal suppression. The evaluation of the toxicity of new formulation has critical role in the pharmaceutical development. The use of cell culture experiments can help this aspect. Additionally, nanotechnology is an important tool to solve problems regarding bioavailability and to circumvent adverse effects of conventional therapy. The aim of this work was to develop a nanostructured system as dry powder inhaler (DPI) containing budesonide loaded, obtained by spray-drying, targeting the treatment of acute and chronic asthma. This proposal was based on obtaining a nanostructured powder system with reduced and controlled size, aiming an alternative to treatment of asthma. A factorial study comparing different methods to produce the nanocapsules as well as the type of drying adjuvants was performed. The particle size of the selected formulation was 2.7 μm, an adequate reduced size suitable for pulmonary administration. The morphology of these particles showed a small size, spherical shape and irregular surface. All these characteristics are important for pulmonary administration. When analyzed the in vitro pulmonary distribution of the DPI, using an Andersen Cascade Impactor, showed a fine particle fraction (FPF) of 28%. Analyzing the results of the biological experiments, the mechanical respiratory and pulmonary function showed a decrease in lung elastance and resistance when budesonide was used nanoencapsulated compared with a commercial formulation of budesonide in two doses (0.5 and 1.0 mg / kg). Both treatments also showed nanocapsules efficiency in reduction of inflammation by reducing the total of leukocytes in the bronchial alveolar lavage fluid (BALF) and especially significant reduction in eosinophil infiltration in the lung tissue. Corroborating with these results, the quantification of eotaxin - 1 and proinflammatory cytokines was reduced when compared to commercial budesonide treatment. Histopathological analysis showed that when treatment with the nanocapsules was used, mucus production was reduced and reversed the phenomena of airway remodeling. The cytotoxicity assay by Alamar blue using the bronchial epithelium cell line (H441) showed a reduction on the toxicity of budesonide when the nanocapsules were used even in suspension or in the DPI. The cytotoxicity reduction were 75 and 50%, at 100 μg/mL, for the suspension and the DPI, respectively. All these results show that budesonide-loaded nanocapsules in dry powder inhaler is a promising approach for the treatment of asthma.
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Advanced Design and Development of Novel Microparticulate/Nanoparticulate Dry Powder Inhalers Targeting Underlying Mechanisms in Respiratory DiseasesMuralidharan, Priyadarshini, Muralidharan, Priyadarshini January 2017 (has links)
Chronic respiratory diseases such as asthma, COPD, pulmonary fibrosis are more prevalent throughout the world. For some of these diseases there is no cure, the current treatment options manages the symptoms and acute exacerbation. The new approach to find a curative therapy for respiratory diseases is by targeting the cellular / molecular pathways that either cause the disease or has the potential cure the disease. It becomes important to target the respiratory system in treating these diseases to increase the delivered dose and reduce the unwarranted adverse effects. Dry powder inhaler (DPI) is a targeted drug delivery dosage form commonly used to target the airways to treat respiratory diseases. There are two components to dry powder inhaler product – powdered drug formulation and inhaler device; a unified performance of the two is essential for a successful product. In this study, dry powder aerosol of novel drug compounds that targets the underlying cellular and molecular mechanism are developed for the first time. Advanced organic closed mode spray drying technique was used to the produce microparticulate/ nanoparticulate formulations. The formulation of the novel compounds involved utilizing sugar based excipients. Each formulation that was produced was comprehensively characterized in the solid state. The safety of these formulations were tested in in vitro human pulmonary cell lines. The in vitro aerosol dispersion of the spray dried drugs were tested using three FDA approved human inhaler devices. The influence of the inhaler device resistance and spray drying process conditions on the aerosol dispersion was evaluated. Preliminary testing of the formulations in in vivo animal models shows promising results in treating chronic respiratory diseases with these superior aerosol formulations.
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UNDERSTANDING AND IMPROVING MANUFACTURING PROCESSES FOR MAKING LITHIUM-ION BATTERY ELECTRODESAL-Shroofy, Mohanad N. 01 January 2017 (has links)
Lithium-ion batteries (LIBs) have been widely used as the most popular rechargeable energy storage and power sources in today’s portable electronics, electric vehicles, and plug-in hybrid electric vehicles. LIBs have gained much interest worldwide in the last three decades because of their high energy density, voltage, rate of charge and discharge, reliability, and design flexibility. I am exploring the possibility of developing battery manufacturing technologies that would lower the cost, reduce the environmental impact, and increase cell performance and durability.
This dissertation is focused firstly on understanding the effect of mixing sequence (the order of introducing materials) and optimizing the electrode fabrication for the best electrochemical performance, durability, lower cost, and improve the existing manufacturing processes. The electrode system consists of active material, polymer binder, conductive agent, and solvent. I have investigated four different mixing sequences to prepare the slurries for making the positive electrode. The key sequence-related factor appears to be whether the active material and conductive agent are mixed in the presence of or prior to the introduction of the binder solution. The mixing sequences 1, 2, 3, and 4 were optimized, and the rheological behavior of the slurries, morphology, conductivity, and mechanical and electrochemical properties of electrodes were investigated. Slurries from sequences 1 and 4 show different rheological properties from 2 and 3. The amount of NMP required to achieve a comparable final slurry viscosity differed significantly for the sequences under study. The sequence 1 shows better long-term cycling behavior than sequences 2, 3 and 4. This study quantifies the link between electrode slurry mix parameters and electrode quality.
Secondly, a new method of making lithium-ion battery electrodes by adapting an immersion precipitation (IP) technology commonly used in membrane manufacturing was developed and demonstrated. The composition, structure, and electrochemical performance of the electrode made by the IP method were compared favorably with that made by the conventional method. The toxic and expensive organic solvent (NMP) was captured in coagulation bath instead of being released to the atmosphere. The IP electrodes show an excellent performance and durability at potentially lower cost and less environmental impact.
Thirdly, I have developed and demonstrated a solvent-free dry-powder coating process for making LiNi1/3Mn1/3Co1/3O2 (NMC) positive electrodes in lithium-ion batteries, and compared the performance and durability of electrodes made by the dry-powder coating processes with that by wet-slurry coating processes. The technology that has been used is the electrostatic spray deposition (ESD) process. This process eliminates volatile organic compound emission, reduces thermal curing time from hours to minutes, and offers high deposition rates onto large surfaces. The long-term cycling shows that the dry-powder coated electrodes have similar performance and durability as the conventional wet-slurry made electrodes.
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