Microemulsion Formulations for the Transdermal Delivery of Lapachol.

This project was carried out to investigate the feasibility of using microemulsions for transdermal delivery of lapachol. From the screening of surfactants and oils, a range of microemulsions were developed using oleic acid, a mixture of Cremophor EL and Tween 20 and water. The solubility of lapachol was determined in these ingredients and in the formulated microemulsions. The microemulsions were characterised using cross-polarising light microscopy, their electrical conductivity, pH, zeta potential and rheology were analysed, and they were also investigated using small-angle X-ray scattering and differential scanning calorimetry. Ex vivo studies were performed using porcine ear skin and Franz diffusion cells to investigate the permeation and retention of lapachol. Systems containing different concentrations of Cremophor EL (8.4-41.6%), Tween 20 (5.4-41.6%) and oleic acid (12-31.9%) are able to form microemulsions. Lapachol was delivered more effectively through the skin from all of the microemulsions tested than by the control (oleic acid). These studies indicated that microemulsions incorporating lapachol were formed successfully and that these enhanced drug delivery and retention in the skin. Microemulsion systems may, therefore, provide promising vehicles for percutaneous delivery of lapachol.

Análise e estudo viscosimétrico de diferentes géis de cetoprofeno 2.5% / Analysis and viscosimetric study of various 2.5% ketoprofen gels

O cetoprofeno é um fármaco pertencente à classe dos anti-inflamatórios não-esteroidais, inibe a síntese de prostaglandinas promovendo um potente efeito analgésico e anti-inflamatório. Para uso tópico, está disponível como medicamento de referência e diversos genéricos sob a forma gel 2,5%, além das preparações manipuladas em farmácias magistrais, adquiridas mediante receita médica. Este estudo objetivou avaliar a qualidade do cetoprofeno gel 2,5% manipulado em duas farmácias do Recife (PE) e, posteriormente, compará-lo ao medicamento de referência e a um genérico correspondente. Os resultados das análises mostraram que medicamentos referência e o genérico apresentaram, de forma geral, características semelhantes. As formulações magistrais também mostraram características próximas entre si, mas diferentes dos industrializados, indicando a necessidade de reformulação destas preparações magistrais avaliadas, como obediência à legislação vigente RDC 67/2007 da Agência Nacional de Vigilância Sanitária.

Ketoprofen is a non-steroidal anti-inflammatory drug that inhibits prostaglandin synthesis and promotes a strong analgesic and anti-inflammatory effect. For topical use, it is available as a reference drug as well as several generic preparations in gel at 2.5%, apart from preparations compounded in pharmacies and sold under medical prescription. The aim of this study was to assess the quality of 2.5% ketoprofen gels compounded in two pharmacies in Recife and then compare them with a reference drug and a corresponding generic drug. The results of the analysis show that the generic and reference drugs display, in general, similar characteristics. The compounded formulations also had similar characteristics, when compared to each other, but were different from the manufactured gels. These results indicate that these compounded preparations must be reformulated to comply with RDC 67/2007, the current regulation issued by the National Agency of Sanitary Surveillance (ANVISA).

Assay and physicochemical characterization of the antiparasitic albendazole

The aim of this study was to characterize three batches of albendazole by pharmacopeial and complementary analytical techniques in order to establish more detailed specifications for the development of pharmaceutical forms. The ABZ01, ABZ02, and ABZ03 batches had melting points of 208 ºC, 208 ºC, and 209 ºC, respectively. X-ray diffraction revealed that all three batches showed crystalline behavior and the absence of polymorphism. Scanning electron microscopy showed that all the samples were crystals of different sizes with a strong tendency to aggregate. The samples were insoluble in water (5.07, 4.27, and 4.52 mg mL-1, respectively) and very slightly soluble in 0.1 M HCl (55.10, 56.90, and 61.70 mg mL-1, respectively) and additionally showed purities within the range specified by the Brazilian Pharmacopoeia 5th edition (F. Bras. V; 98% to 102%). The pharmacopeial assay method was not reproducible and some changes were necessary. The method was validated and showed to be selective, specific, linear, robust, precise, and accurate. From this characterization, we concluded that pharmacopeial techniques alone are not able to detect subtle differences in active pharmaceutical ingredients; therefore, the use of other complementary techniques is required to ensure strict quality control in the pharmaceutical industry.

O objetivo do trabalho foi caracterizar três lotes de albendazol com técnicas analíticas farmacopéicas e complementares a fim de estabelecer especificações mais detalhadas para o desenvolvimento de formas farmacêuticas. Os lotes ABZ01, ABZ02 e ABZ03 apresentaram fusão em 208 ºC, 208 ºC e 209 ºC. Foi possível evidenciar, por difração de raios X, que os três lotes apresentaram comportamento cristalino e ausência de polimorfismo. Através da microscopia eletrônica de varredura verificou-se que todas as amostras apresentaram cristais com diferentes tamanhos e forte tendência de agregação. As amostras foram insolúveis em água (5,07; 4,27 e 4,52 µg mL-1) e muito pouco solúveis em HCl 0,1M (55,10; 56,90 e 61,70 µg mL-1) e, ainda, apresentaram pureza dentro da faixa especificada pela F.Bras.V (98% a 102%). O método farmacopéico de doseamento não foi reprodutível, e algumas mudanças foram necessárias. O método foi validado e demonstrou ser seletivo, específico, linear, robusto, preciso e exato. A partir dessa caracterização, pode-se concluir que apenas técnicas farmacopéicas não são capazes de detectar diferenças sutis entre os ingredientes farmacêuticos ativos, necessitando, portanto, de uso de outras técnicas complementares para garantir um rígido controle de qualidade na indústria farmacêutica.