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Master's Dissertation
DOI
Document
Author
Full name
Ana Paula Navarro de Almeida Zerbini
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2010
Supervisor
Committee
Ferraz, Humberto Gomes (President)
Andréo Filho, Newton
Santos, Carlos de Oliveira Paiva
Title in Portuguese
Desenvolvimento e avaliação de minicomprimidos contendo atorvastatina cálcica
Keywords in Portuguese
Atorvastatina cálcica
Dissolução
Formas farmacêuticas
Minicomprimidos
Polimorfismo
Abstract in Portuguese
O objetivo do presente trabalho foi desenvolver e avaliar minicomprimidos obtidos a partir de quatro formas polimórficas de atorvastatina cálcica. Inicialmente foi realizada uma caracterização físico-química das amostras (amorfa e formas cristalinas I, VI e VIII), empregando-se os ensaios de dissolução intrínseca e solubilidade através dos métodos do disco rotacional e do equilíbrio, respectivamente. Na sequência, foi realizada a caracterização do estado sólido por difração de raios-x, DSC (differencial scanning calorimetry) e termogravimetria. Foi observado que o polimorfo VIII demonstrou maior velocidade de dissolução intríseca, seguido pelas formas amorfa, VI e I. Adicionalmente, foram avaliadas as propriedades das partículas de atorvastatina cálcica a fim de verificar sua influência nos resultados de solubilidade e dissolução intrínseca. As seguintes análises foram conduzidas: tamanho e distribuição do tamanho de partícula, densidades (aparente, compactada e verdadeira), microscopia eletrônica de varredura, área superficial, termogravimetria derivada e solubilidade com tensoativo. Os resultados demonstraram diferenças significativas dentre as partículas das amostras avaliadas, principalmente quanto à morfologia e área superficial, as quais podem ter influenciado os resultados de dissolução intrínseca. Finalmente, definiu-se uma formulação de minicomprimidos que foi preparada com as quatro amostras do fármaco através do processo de compressão direta, utilizando-se um punção múltiplo com 3 pontas, de 3 mm cada. As formulações foram avaliadas quanto ao peso médio, dureza, friabilidade, espessura, teor e perfil de dissolução. Os resultados indicaram que as diferentes formas de atorvastatina cálcica são capazes de influenciar o perfil de liberação do fármaco a partir da formulação proposta, reforçando a importância do estudo de pré-formulação no desenvolvimento de formas farmacêuticas sólidas contendo atorvastatina cálcica.
Title in English
Development and evaluation of minitablets containing atorvastatin calcium
Keywords in English
Atorvastatin calcium
Dissolution
Minitablets
Pharmaceutical forms
Polymorphism
Abstract in English
The purpose of this study was to develop and evaluate minitablets obtained from four polymorphic forms of atorvastatin calcium. Initially, the physicochemical characterization of the samples (amorphous and forms I, VI and VIII) was made by applying the intrinsic dissolution rate and solubility studies using the rotation disk and shake-flask methods, respectively. Further, the solid state characterization was made by means of x-ray powder diffraction, differential scanning calorimetry and termogravimetric analysis. It was observed that the polymorph VIII showed the highest intrinsic dissolution rate, followed by the amorphous form, polymorph VI and I. Additionally, the particle properties were evaluated in order to check its influence on the solubility and intrinsic dissolution results previous obtained. The following tests were conducted: size and size distribution of the particles, densities (apparent, compacted and true), scanning electron microscopy, surface area, differential termogravimetric analysis and solubility with surfactant. The results showed significant differences between the particles of the samples, especially in terms of morphology and surface area, which may have influenced the results of the intrinsic dissolution. Finally, a minitablet formulation was defined and prepared with the four samples of the drug by direct compression process, with a multi tip punch with 3 tips of 3 mm each one. The formulations were analyzed regarding their weight, hardness, friability, thickness, assay and dissolution profile. The results suggested that the different forms of atorvastatin calcium are capable of influencing the dissolution profile of the drug from the proposed formulation, reinforcing the importance of the preformulation study in the development of solid dosage forms with atorvastatin calcium.
 
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Dissertacaoresdig.pdf (35.85 Kbytes)
Publishing Date
2010-12-06
 
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