A suitable and efficient high-performance liquid chromatography (HPLC) method was developed for the simultaneous determination of tuberculostatic isoniazid and its related impurities, isonicotinic acid and isonicotinamide, in oral solid dosage forms. We studied the influence on chromatographic separation of mobile phase parameters, such as pH, ion pairing and ionic strength, as well as column bonded phase and brands. The use of buffer solution pH 6.8:acetonitrile 96:4 (v/v) at 0.8 mL min-1, C18 column (250 × 4.6 mm, 5 µm), allowed proper separation of these ionizable analytes without the need of ion pairing agents. The limit of quantification of the method (0.1 µg mL-1) was suitable for the analysis of impurities. A drug-excipient compatibility study was carried out with the anaytical method proposed in this work and addressed frequent excipients used in isoniazid coated tablets. The dye FD&C blue 2 lake promoted the highest degradation of the tuberculostatic agent.

Mosquitos são responsáveis pela transmissão de várias doenças causadas por vírus, parasitas e helmintos. Considerando o custo e a complexidade do tratamento dessas doenças, o uso de repelentes para proteção contra mosquitos vetores se torna uma alternativa interessante. Nesse contexto, no presente trabalho foram feitos estudos por ancoramento e dinâmica molecular (DM) de potenciais ligantes da proteína odorante do mosquito Anopheles gambiae (AgOBP1), o principal vetor da malária. Os modos de ligação na AgOBP1 de moléculas com conhecida atividade atrativa e dos principais componentes do óleo do cravo da índia (Syzygium aromaticum), com potencial atividade repelente, foram comparados com o conhecido repelente N,N-dietil-3-metilbenzamida (DEET). Os resultados sugerem que o acetato de eugenila é um repelente melhor do que o DEET e também revelam as principais características do sítio de ligação da AgOBP1 importantes para o planejamento de novos e mais eficientes repelentes.

Mosquitoes are responsible for conveying various diseases caused by viruses, parasites and helminthes. Considering the cost and complexity of the treatment of these diseases, the use of repellents for protection from the mosquito vectors becomes an interesting alternative. In the present work, docking and molecular dynamics (MD) studies were performed on potential ligands to the odorant binding protein of the mosquito Anopheles gambiae (AgOBP1), the main vector of malaria. The binding modes on AgOBP1 of molecules with known attractive activities and the main components of the oil of indian clove (Syzygium aromaticum) with potential repellent activities were compared to the known repellent N,N-diethyl-3-methylbenzamide (DEET). Results suggest the eugenyl acetate as a better repellent than DEET and also reveal the main features of the binding site of AgOBP1 important to the design of new and more efficient repellents.