Development of nanoencapsulation forms from Cymbopogon citratus essential Oil

Cymbopogon citratus essential oil (CCEO) is widely used in food, cosmetics and pharmaceutical fields. The aim of this study was to compare two different methods of encapsulating CCEO. The o/w emulsion method was employed here for the first time for producing CCEO nanoparticles with polycaprolactone (PCL) and a molecular inclusion in β-cyclodextrin (CyD) using the precipitation method. The nanoparticles were spherical in shape, with 240.0 nm mean diameter and demonstrated a higher encapsulation efficiency (36.51 %) as the citral content. The efficiency of CCEO/CyD complex was lower (9.46 %) and it showed some specificity for the smallest molecules present in the original oil. It was irregular in shape and had a larger mean diameter (441.2 nm). It was concluded that the o/w emulsion method was the most effective for CCEO encapsulation. The positive findings in this study encourage further research and provide perspectives for the development of phytotherapeutic products from CCEO.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Efavirenz Dissolution Enhancement I: Co-Micronization

AIDS constitutes one of the most serious infectious diseases, representing a major public health priority. Efavirenz (EFV), one of the most widely used drugs for this pathology, belongs to the Class II of the Biopharmaceutics Classification System for drugs with very poor water solubility. To improve EFV’s dissolution profile, changes can be made to the physical properties of the drug that do not lead to any accompanying molecular modifications. Therefore, the study objective was to develop and characterize systems with efavirenz able to improve its dissolution, which were co-processed with sodium lauryl sulfate (SLS) and polyvinylpyrrolidone (PVP). The technique used was co-micronization. Three different drug:excipient ratios were tested for each of the two carriers. The drug dispersion dissolution results showed significant improvement for all the co-processed samples in comparison to non-processed material and corresponding physical mixtures. The dissolution profiles obtained for dispersion with co-micronized SLS samples proved superior to those of co-micronized PVP, with the proportion (1:0.25) proving the optimal mixture. The improvements may be explained by the hypothesis that formation of a hydrophilic layer on the surface of the micronized drug increases the wettability of the system formed, corroborated by characterization results indicating no loss of crystallinity and an absence of interaction at the molecular level

Efavirenz Dissolution Enhancement I: Co-Micronization

AIDS constitutes one of the most serious infectious diseases, representing a major public health priority. Efavirenz (EFV), one of the most widely used drugs for this pathology, belongs to the Class II of the Biopharmaceutics Classification System for drugs with very poor water solubility. To improve EFV’s dissolution profile, changes can be made to the physical properties of the drug that do not lead to any accompanying molecular modifications. Therefore, the study objective was to develop and characterize systems with efavirenz able to improve its dissolution, which were co-processed with sodium lauryl sulfate (SLS) and polyvinylpyrrolidone (PVP). The technique used was co-micronization. Three different drug:excipient ratios were tested for each of the two carriers. The drug dispersion dissolution results showed significant improvement for all the co-processed samples in comparison to non-processed material and corresponding physical mixtures. The dissolution profiles obtained for dispersion with co-micronized SLS samples proved superior to those of co-micronized PVP, with the proportion (1:0.25) proving the optimal mixture. The improvements may be explained by the hypothesis that formation of a hydrophilic layer on the surface of the micronized drug increases the wettability of the system formed, corroborated by characterization results indicating no loss of crystallinity and an absence of interaction at the molecular level

Elucidating the crystal structure of the antimalarial drug (+/-)-mefloquine hydrochloride: a tetragonal hydrated species

Albeit widely studied, the structure of the antimalarial drug (+/-)-mefloquine hydrochloride is still a controversial issue. A combination of X-ray powder diffraction, theoretical calculations and Fourier transform-infrared spectroscopy is used to unambiguously determine the crystal structure of the molecule in its active pharmaceutical ingredient. It is demonstrated that water is incorporated into the structure, leading to a hydrated form and, most importantly, to significant differences in both structure and bonding. Such changes can lead to significant differences in biological activity. (C) 2014 International Union of CrystallographyFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES