10 research outputs found

    Development and validation of an intrinsic dissolution method for nimodipine polymorphs

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    The polymorphs of nimodipine, Modification I (Mod I), the metastable racemate, and Modification II (Mod II), the stable conglomerate, were evaluated by means of the intrinsic dissolution procedure. for this purpose, a hydro alcoholic solution (ethanol:water, 50:50, v/v) was selected as the dissolution medium, maintained at 37 +/- 0.5A degrees C. Different rotation speeds were tested (50, 75 and 100 rpm) and the lower one was chosen for the test validation. Although the sample initially characterized as polymorph Mod I presented higher intrinsic dissolution rates in all the conditions tested, no statistical differences were noticed between the two polymorphs. This result can be attributed to the partial solution-mediated phase transformation from Mod I to Mod II, detected through X-ray powder diffraction and differential scanning calorimetry. Also, reliable intrinsic dissolution rate data were acquired for the polymorph Mod II. the dissolution method was validated, being considered stable, specific, linear, sensible, accurate and precise.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundacao de Amparo a Pesquisa do Estado de Santa Catarina (FAPESC)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Univ Fed Santa Catarina, Postgrad Program Pharm, BR-88040970 Florianopolis, SC, BrazilUniversidade Federal de São Paulo, BR-12231280 Sao Jose Dos Campos, SP, BrazilUniversidade Federal de São Paulo, BR-12231280 Sao Jose Dos Campos, SP, BrazilWeb of Scienc

    Development and validation of a stability-indicating HPLC method for the determination of buclizine hydrochloride in tablets and oral suspension and its application to dissolution studies

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    A method using liquid chromatography has been developed and validated for determination of buclizine in pharmaceutical formulations and in release studies. Isocratic chromatography was performed on a C18 column with methanol:water (80:20 v/v, pH 2.6) as mobile phase, at a flow rate of 1.0 mL/min, and UV detection at 230 nm. The method was linear, accurate, precise, sensible and robust. The dissolution test was optimized and validated in terms of dissolution medium, apparatus agitation and rotation speed. The presented analytical and dissolution procedures can be conveniently adopted in the quality and stability control of buclizine in tablets and oral suspension

    Solid-state characterization and dissolution properties of Fluvastatin sodium salt hydrates

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    The present study reports the solid-state properties of Fluvastatin sodium salt crystallized from different solvents for comparison with crystalline forms of the commercially available raw material and United States Pharmacopeia (USP) reference standard. FLV samples were characterized by several techniques; such as X-ray powder diffractometry, differential scanning calorimetry, thermogravimetry, liquid and solid-state nuclear magnetic resonance spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy, and scanning electron microscopy. In addition, intrinsic dissolution rate (IDR) of samples was performed in order to study the influence of crystalline form and other factors on rate and extent of dissolution. Three different forms were found. The commercial raw material and FluvastatinACN were identified as “form I” hydrate, the USP reference standard as “form II” hydrate and an ethanol solvate which presented a mixture of phases. Form I, with water content of 4%, was identified as monohydrate.Fil: Borgmann, Silvia H. M.. Universidade Federal de Santa Catarina; BrasilFil: Bernardi, Larissa S.. Universidade Federal de Santa Catarina; BrasilFil: Rauber, Gabriela S.. Universidade Federal de Santa Catarina; BrasilFil: Oliveira, Paulo R.. Universidade Federal de Santa Catarina; BrasilFil: Campos, Carlos E.M. de. Universidade Federal de Santa Catarina; BrasilFil: Monti, Gustavo Alberto. Universidade Federal de Santa Catarina; Brasil. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Cuffini, Silvia L.. Universidade Federal de Santa Catarina; BrasilFil: Cardoso, Simone. Universidade Federal de Santa Catarina; Brasi

    Polymorphism of Anti-HIV Drug Efavirenz: Investigations on Thermodynamic and Dissolution Properties

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    Polymorphs, cocrystals, solvates, and hydrates have been reported for efavirenz (EFV), which is part of high activity antiretroviral therapy (HAART), and it is considered to be the best choice in the treatment of adults and children. However, studies about thermodynamic stability and improvement of dissolution properties have been rarely reported for the anhydrous polymorphic forms. Therefore, the aim of this work was to characterize the solid state of anhydrous polymorph I and polymorph II (herein obtained), to study the thermodynamic stability and strategies to improve the dissolution properties. in addition, techniques such as, X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), hot stage microscopy (HSM), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), raman spectroscopy (RS), theoretical calculations, and solid-state nuclear magnetic resonance (ss-NMR) were used to complete this work. Thermodynamic studies showed that polymorphs I and II are enantiotropically related with the isoenergetic point between 35 and 40 degrees C. the EFV polymorph II showed itself to be more stable and 10-fold more soluble than polymorph I, due to modifications of morphology. Therefore, polymorph II could be an excellent candidate with significant advantages for pharmaceutical formulations.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FAPESCCLAFFundacion SauberanPDTIS/FIOCRUZUniv Fed Santa Catarina, Lab Controle Qualidade, BR-88040900 Florianopolis, SC, BrazilUniv Costa Rica, Escuela Quim, San Jose 2060, Costa RicaUniv Fed Santa Catarina, Dept Fis, Lab Difracao RaioX, BR-88040900 Florianopolis, SC, BrazilFiocruz MS, Inst Tecnol Farmacos Farmanguinhos, Lab Sistemas Farmaceut Avancados, BR-22775610 Rio de Janeiro, BrazilUniv Nacl Cordoba, FaMAF, RA-5000 Cordoba, ArgentinaIFEG CONICET, RA-5000 Cordoba, ArgentinaUniversidade Federal de São Paulo, Posgrad Engn & Ciencias Mat, BR-12231280 São Paulo, BrazilUniversidade Federal de São Paulo, Posgrad Engn & Ciencias Mat, BR-12231280 São Paulo, BrazilWeb of Scienc

    COCRISTAIS: UMA ESTRATÉGIA PROMISSORA NA ÁREA FARMACÊUTICA

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    Pharmaceutical cocrystals have emerged as a useful strategy to improve the aqueous solubility of poorly water soluble drugs by aiming to enhance their oral absorption and bioavailability. Aqueous cocrystal solubility can be orders of magnitude higher than that of the constituent drug and this solubility advantage can be fine-tuned based on environmental conditions such as pH and the presence of drug solubilizing agents. This review presents a brief overview of pharmaceutical cocrystals regarding cocrystal design, obtainment methods, with particular focus on cocrystal solubility, and the solubility modulation by solution phase chemistry

    COCRISTAIS: UMA ESTRATÉGIA PROMISSORA NA ÁREA FARMACÊUTICA

    No full text
    Pharmaceutical cocrystals have emerged as a useful strategy to improve the aqueous solubility of poorly water soluble drugs by aiming to enhance their oral absorption and bioavailability. Aqueous cocrystal solubility can be orders of magnitude higher than that of the constituent drug and this solubility advantage can be fine-tuned based on environmental conditions such as pH and the presence of drug solubilizing agents. This review presents a brief overview of pharmaceutical cocrystals regarding cocrystal design, obtainment methods, with particular focus on cocrystal solubility, and the solubility modulation by solution phase chemistry
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