Empagliflozin: Validation of Stability-Indicating LC Method and in silico Toxicity Studies.

A new stability-indicating liquid chromatography method was developed for the quantification of empagliflozin and two synthetic impurities. The chromatographic conditions included Spherisorb® RP-18 column (150 × 4.6 mm, 5 µm) with a PDA detector, using acetonitrile and formic acid (pH 4.0) as mobile phase in gradient elution and flow-rate of 1.2 mL·min-1. The gradient increasing from 51 to 100% acetonitrile until 11.00 min, followed by decreasing the solvent from 100% to the initial ratio from 11.01 to 15.00 min. The method was validated according to International Council of Harmonization guidelines. The LOD and LOQ values for impurities A and B were 35 and 15 ng·mL-1, respectively, (for LOD) and 115 and 35 ng.mL-1, respectively (for LOQ). The method was linear in the range of 80-140, 115-1150 and 35-350 ng·mL-1 for EMPA, impurities A and B, respectively, and the correlation coefficient were > 0.999 in all situations, indicating the method good linearity. The developed method showed a good recovery for empagliflozin and added impurities. The method has proven to be precise, demonstrated values less than 2.0% to empagliflozin and 5.0% to synthetic impurities, robust and selective with no interference from other products in the determination of analytes. The in silico toxicity prediction suggested that the impurities do not present any toxicity risk for the parameters evaluated.

Luliconazole: Stability-indicating LC method, structural elucidation of major degradation product by HRMS and in silico studies / Luliconazol: método por LC indicativo de estabilidad, elucidación estructural del producto de degradación mayoritario por HRMS y estudios in silico / Luliconazol: método LC indicativo de estabilidade, elucidação estrutural do principal produto de degradação por HRMS e estudos in sílico

SUMMARY Aim: A new stability-indicating liquid chromatography method was developed and validated for the quantitative determination of luliconazole. Materials and methods: Preliminary forced degradation study demonstrated an additional peak of the degradation product at the same retention time to the drug, due to this, the method was developed optimizing the chromatographic conditions to provide sufficient peak resolution (R ≥ 2). The experimental design was evaluated to assess the robustness and the best chromatographic conditions to be used for the validation. Methodology: Luliconazole solutions were exposed to various stress conditions to evaluate the method indication stability, in which the degradation product (DP-1) formed was isolated, identified, and evaluated in silico to predict degradation pathway and toxicity. The procedure was validated by robustness, selectivity, linearity, precision, and accuracy. Liquid chromatography was performed in a Phenomenex® RP-18 column with a mixture of acetonitrile and 0.3% (v/v) triethylamine solution as a mobile phase in isocratic elution. Results and conclusions: The method demonstrated robustness, good recovery, precision, linear response over a range from 5.0 to 40.0 μg.mL-1- and to be stability indicating. The alkaline stress condition resulted in the formation of DP-1. HRMS studies identified this product as an hydroxyacetamide derivative, and in silico studies did not show toxic potential.

RESUMEN Objetivo: Un nuevo método indicativo de estabilidad por cromatografía líquida fue desarrollado y validado para la determinación cuantitativa de luliconazol. Materiales y métodos: Estudios preliminares de degradación forzada demostraron un pico adicional en el mismo tiempo de retención del fármaco. El método desarrollado para optimizar las condiciones cromatográicas proporcionó una adecuada resolución (R ≥ 2). El diseño experimental fue evaluado para verificar su robustez y la mejor condición cromatográica para validación. Metodología: Las soluciones de luliconazol fueron expuestas a diferentes condiciones de estrés para evaluar la indicación de estabilidad del método, el aislamiento del producto de degradación formado (DP-1), su identificación y análisis in silico para predecir su ruta de degradación y toxicidad. El procedimiento se validó por robustez, selectividad, linealidad, precisión y exactitud. Las condiciones cromatográficas incluyeron una columna Phenomenex® RP-18, como fase móvil una mezcla de acetonitrilo y solución 0,3% (v/v) de trietilamina en elución isocrática. Resultados y conclusiones: El método mostró ser robusto, con buena recuperación, precisión, respuesta lineal en el rango de 5,0 a 40,0 μg.mL-1 e indicativo de la estabilidad. La condición de estrés alcalina resultó en la formación de DP-1. Estudios por HRMS identificaron este producto como un derivado hidroxiacetamida y los estudios in silico no mostraron potencial de toxicidad.

RESUMO Objetivo: Um novo método indicativo de estabilidade por cromatograia líquida foi desenvolvido e validado para a determinação quantitativa de luliconazol. Materiais e métodos: Estudos preliminares de degradação forçada demonstraram um pico adicional no mesmo tempo de retenção do medicamento. O método desenvolvido para otimizar as condições cromatográficas proporcionou resolução adequada (R ≥ 2). O delineamento experimental foi avaliado para verificar sua robustez e a melhor condição cromatográica para validação. Metodologia: Soluções de luliconazol foram expostas a diferentes condições de estresse para avaliar a indicação da estabilidade do método, o isolamento do produto de degradação formado (DP-1), sua identificação e análise in silico para predizer sua rota de degradação e toxicidade. O procedimento foi validado quanto à robustez, seletividade, linearidade, precisão e exatidão. As condições cromatográficas incluíram uma coluna Phenomenex® RP-18, como fase móvel uma mistura de acetonitrila e solução de trietilamina 0,3% (v/v) em eluição isocrática. Resultados e conclusões: O método mostrou-se robusto, com boa recuperação, precisão, resposta linear na faixa de 5,0 a 40,0 μg.mL-1 e indicativo de estabilidade. A condição de estresse alcalino resultou na formação de DP-1. Os estudos da HRMS identificaram este produto como um derivado da hidroxiacetamida e os estudos in silico não mostraram nenhum potencial de toxicidade.

The use of Brazilian vegetable oils in nanoemulsions: an update on preparation and biological applications

ABSTRACT Vegetable oils present important pharmacological properties, which gained ground in the pharmaceutical field. Its encapsulation in nanoemulsions is considered a promising strategy to facilitate the applicability of these natural compounds and to potentiate the actions. These formulations offer several advantages for topical and systemic delivery of cosmetic and pharmaceutical agents including controlled droplet size, protection of the vegetable oil to photo, thermal and volatilization instability and ability to dissolve and stabilize lipophilic drugs. For these reasons, the aim of this review is to report on some characteristics, preparation methods, applications and especially analyze recent research available in the literature concerning the use of vegetable oils with therapeutic characteristics as lipid core in nanoemulsions, specially from Brazilian flora, such as babassu (Orbignya oleifera), aroeira (Schinus molle L.), andiroba (Carapa guaianiensis), casca-de-anta (Drimys brasiliensis Miers), sucupira (Pterodon emarginatus Vogel) and carqueja doce (Stenachaenium megapotamicum) oils.

Morfoanatomia das folhas de Dodonaea viscosa Jacq., Sapindaceae / Morph-anatomy of the leaves of Dodonaea viscosa Jacq., Sapindaceae

Dodonaea viscosa Jacq., Sapindaceae, é uma planta tradicionalmente utilizada como antifebril, anti-reumática e antimicrobiana. Neste trabalho foram determinados parâmetros morfo-anatômicos, por análise macro e microscópicas, das folhas de Dodonaea viscosa, com o objetivo de auxiliar sua diagnose como insumo farmacêutico. Macroscopicamente as folhas apresentam limbo com forma lanceolada, margem inteira, consistência áspera e venação eucamptódroma. O pecíolo é curto, reto e em seção transversal é triangular com os ângulos arredondados. Microscopicamente destaca-se a cutícula com formações lenticulares, os tricomas glandulares com quatro células na base, os tricomas tectores unicelulares de ápice afilado, os estômatos higrofíticos dispostos apenas na face abaxial da epiderme, o parênquima paliçádico com até três camadas de células e os feixes vasculares com xilema envolto por floema e cordões de parênquima que ligam um maciço central de células de parênquima a uma bainha de esclerênquima. Estas características morfo-anatômicas, quando analisadas em conjunto, contribuem no controle botânico de qualidade das folhas de Dodonaea viscosa como insumo farmacêutico.

Dodonaea viscosa Jacq., Sapindaceae, is a plant traditionally used as anti fever, anti- rheumatic and antimicrobial. This work determined morpho-anatomical parameters, by macro and microscopic analysis of Dodonaea viscosa leaves, aiming to reach their diagnosis as pharmaceutical input. Macroscopically, the leaves have a lanceolate shape limb, full margin, rough consistence and venation eucamptodromous. The petiole is short, straight and in transversal section it is triangular with round angles. Microscopically, the lenticullar formation cuticle is seen with prominence, the glandular thricomes are seen with four cells on the base, the non-glandular unicellular thricomes are seen with pointed apex, the higrophitic stomatas are disposed in the lower surface epidermis only, the palisade parenchyma show up to three-cell layers and vascular bundles with xylem involved by phloem and parenchyma lines which bound a central mass of parenchyma cells to a sclerenchyma sheath. This morph-anatomical characteristic, when analyzed in group, contributes to the botanical quality control of Dodonaea viscosa leaves as pharmaceutical input.