Examinando por Autor "Alvarez, Vera A."

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    ÍtemAcceso Abierto
    Miconazole Nitrate Microparticles in Lidocaine Loaded Films as a treatment for Oropharyngeal Candidiasis
    (MDPI, 2023-05-07) Tejada, Guillermo; Calvo, Natalia Lorena; Morri, Mauro; Sortino, Maximiliano Andrés; Lamas, María Celina; Alvarez, Vera A.; Leonardi, Darío; https://orcid.org/0000-0002-4457-9099; https://orcid.org/0000-0003-1099-3686; https://orcid.org/0000-0002-4271-1690; https://orcid.org/0000-0002-4909-4592; https://orcid.org/0000-0003-2292-3570
    Oral candidiasis is an opportunistic infection that affects mainly individuals with weakened immune system. Devices used in the oral area to treat this condition include buccal films, which present advantages over both oral tablets and gels. Since candidiasis causes pain, burning, and itching, the purpose of this work was to develop buccal films loaded with both lidocaine (anesthetic) and miconazole nitrate (MN, antifungal) to treat this pathology topically. MN was loaded in microparticles based on different natural polymers, and then, these microparticles were loaded in hydroxypropyl methylcellulose-gelatin-based films containing lidocaine. All developed films showed adequate adhesiveness and thickness. DSC and XRD tests suggested that the drugs were in an amorphous state in the therapeutic systems. Microparticles based on chitosan-alginate showed the highest MN encapsulation. Among the films, those containing the mentioned microparticles presented the highest tensile strength and the lowest elongation at break, possibly due to the strong interactions between both polymers. These films allowed a fast release of lidocaine and a controlled release of MN. Due to the latter, these systems showed antifungal activity for 24 h. Therefore, the treatment of oropharyngeal candidiasis with these films could reduce the number of daily applications with respect to conventional treatments.
  • Miniatura
    ÍtemAcceso Abierto
    New approaches to identification and characterization of tioconazole in raw material and inpharmaceutical dosage forms
    (Elsevier, 2018-11-23) Calvo, Natalia Lorena; Alvarez, Vera A.; Lamas, María Celina; Leonardi, Darío
    Tioconazole (TCZ), a broad-spectrum antifungal agent, has significant activity against Candida albicans and other Candida species, and therefore, it is indicated for the topical treatment of superficial mycoses. The main goal of this work is to report an exhaustive identification and characterization procedure to improve and facilitate the online quality control and continuous process monitoring of TCZ in bulk material and loaded in two different dosage forms: ovules and nail lacquer. The methodologies were based on thermal (differential scanning calorimetry (DSC), melting point, and thermogravimetry (TG)), spectroscopic (ultraviolet (UV), Raman, near infrared (NIR), infrared spectroscopy coupled to attenuated total reflectance (FTIR-ATR), and nuclear magnetic resonance (NMR)), microscopic and X-ray diffraction (XRD). The TCZ bulk powder showed a high crystallinity, as observed by XRD, with a particles size distribution (3–95 µm) resolved by microscopic measurements. TCZ melting point (82.8 °C) and a degradation peak centered at 297.8 °C were obtained by DSC and DTG, respectively. An unambiguous structure elucidation of TCZ was obtained by mono- and two- dimensional 1H and 13C NMR spectral data analysis. The FTIR-ATR, Raman and NIR spectra of both the raw material and the commercial products were analyzed and their characteristic bands were tabulated. The best methods for TCZ identification in ovules were DSC, TG, XRD, NIR and Raman, while NIR and FTIR-ATR were the most appropriate techniques to analyze it in the nail lacquer. DSC, TG, DRX, Raman, FTIR-ATR and NIR spectroscopy are effective techniques to be used in online process analysis, because they do not require sample preparation, and they are considerably sensitive to analyze complex samples.